630.7
I£6b
no. 724
cop. 8

UNIVERSITY OF

ILLINOIS LIBRARY

AT URBANA-CHAMPAIGN

AGRICULTURE

BULLETIN 724

N

A STUDY OF
THE N'DAMA
CATTLE AT THE
MUSAIA ANIMAL
HUSBANDRY
STATION IN
SIERRA LEONE

R.W.TOUCHBERRY

Published by the
University of Illinois
Agricultural
Experiment Station.
Publication financed under
University of Illinois- AID
Contract USAID / Afr-293
in cooperation with JVjala
University College,
Sierra Leone; Ministry of
Agriculture and Natural
Resources, Sierra Leone;
and University of Illinois
Campus Office
of AID Projects.

CONTENTS

Highlights 2

Cattle Rearing in Sierra Leone 3

The Musaia Animal Husbandry Station 7

The Beef Herd 10

Age at first calving 11

Sex ratio 11

Calving interval 12

Age at disposal and of animals in the herd 12

Death losses 13

Body weights 13

Comparisons of weights of N'Dama, Holstein, and Guernsey cows. 30

Slaughter data 31

Selection for heavier animals at a given age 34

Discussion 36

References 39

Acknowledgments inside back cover

Recommendations . . .back cover

COVER PHOTOS

Top: A milkmaid and a herd of N'Dama cattle
in a warri.

Middle: Selling cottage cheese along a road
south of Musaia.

Bottom: N'Dama beef in a meat market in Bo.

Urbana, Illinois April, 1967

Publications in the Bulletin series report the results of investigations made
or sponsored by the Experiment Station

A STUDY OF

THE N'DAMA

CATTLE AT THE

MUSAIA ANIMAL

HUSBANDRY

STATION IN

SIERRA LEONE

R.W.TOUCHBERRY

Published by the
University of Illinois
Agricultural
Experiment Station.
Publication financed under
University of Illinois- AID
Contract USAID / Afr-293
in cooperation with Njala
University College,
Sierra Leone; Ministry of
Agriculture and Natural
Resources, Sierra Leone;
and University of Illinois
Campus Office
of AID Projects.

Highlights

The live weights of the N'Dama cattle at the Musaia Animal Hus-
bandry Station, Musaia, Sierra Leone, have been recorded monthly
since 1949. In 1965 live weights were available on 986, 871, 795, 555,
372 and 182 animals at birth, 6, 12, 24, 36 and 48 months of age. The
numbers of males and females did not differ significantly until the age
of 36 months.

The average age at first calving was 39.4 months with an average
calving interval of 467 days. Most calves were born in the period from
September through February. A least squares analysis of the data on
weights indicated that the N'Dama cattle at the Musaia station are
small; the least squares means being 36.2, 159.9, 230.8, 287.0, 359.7,
425.5 and 471.4 pounds at birth, 6, 12, 18, 24, 30 and 36 months of
age respectively. Male calves were heavier than females at all ages, and
the weight at a given age was markedly affected by year and month of
birth. Average weight at a given age changed little during the 15
years 1949 through 1963. Heritability of weight at the different ages
was relatively low, being approximately 0.10 to 0.20. Under present
conditions mass selection for weight at one year of age would at best
result in an approximate 12.8 pound increase per generation, or approx-
imately 1.8 pounds per year. The expected genetic gain for weight at
other ages was not appreciably different. For 54 animals, 51 males and
3 females, on which slaughter data were available, the average age at
slaughter was 39.1 months while the mean weight was 512.1 pounds.
The weight of the carcass accounted for only 41.6 percent of the
live weight.

From the above analyses it was concluded that the ability of the
N'Dama cattle to produce meat under Musaia conditions was rather
limited. From reports of other studies (9, 12, 20, 21) it appears that
the ability of the N'Dama to produce milk is also limited. It thus
appears that the main asset of the N'Dama breed is its tolerance (28)
to piroplasmoses, trypanosomiasis, and trypanosomes in general. Just
how well the N'Dama would perform as a producer of meat and milk
under more optimum feeding and management conditions is not really
known; however, the work of Anliker (1), Montsma (20, 21) and
O Korie et al. (24) indicates that under more optimum levels of feeding
the performance of the N'Dama is not as good as that of most European
breeds or the Santa Gertrudis. If crosses between N'Dama and Euro-
pean breeds possess some of the tolerance of the N'Dama to piro-
plasmoses, trypanosomiasis, and trypanosomes in general, N'Dama
crossing schemes should be undertaken to develop cattle for Sierra
Leone that are better producers of meat and milk. Plans for producing
cheap but adequate feed, both concentrate and roughage, for the dry
season should be developed simultaneously with the breeding scheme.

Cof

^ STUDY OF THE N'DAMA CATTLE AT THE MUSAIA
ANIMAL HUSBANDRY STATION IN SIERRA LEONE

R. W. TOUCHBERRY1

Cattle Rearing in Sierra Leone

THE NAME N'Dama can be translated as "small cattle." The N'Dama
cattle are described by Mason (19)* and by Joshi et al. (13) as a
small, humpless, thick-set, dwarf breed. The head is short and broad
with a straight profile, and the neck is of medium length and deep.
From withers to tail setting the topline is flat and well muscled and is
quite straight with a slight tendency to rise at the hind quarters. The
rump has only a slight slope; the sacrum is not prominent; and the tail
is long with a well developed switch. The ribs are well sprung and the
musculature of the shoulders, back, and hind-quarters is rounded and
well developed. The legs are short and fine boned. There is wide varia-
tion in color; fawn is the most common color, while buff, red, dun, black
and mixtures occur less frequently. Horn size shows much variation
but horns are generally long and lyre-shaped; polled animals do occur.
Tolerance to trypanosomiasis and piroplasmoses, together with longev-
ity, thriftiness in the dry season, and ability to endure the unhealthy
conditions of the wet season are given as the main attributes of the
breed. The top photograph on the cover depicts the general appearance
of the N'Dama. All cattle in Sierra Leone are of the N'Dama breed.
A description of the size of the N'Dama in Sierra Leone, the French
Sudan, and the Ivory Coast is given by Joshi et al. (13). Some weights
and measurements of the N'Dama are listed in Table 1 along with
weights and measurements of a sample of Holsteins in the University
of Illinois dairy herd. No indication is given in the data on the N'Dama
cattle of the number and ages of animals measured and weighed at the
different stations. Further, it is not known what confounding effects of
environment may exist at the different stations or between ages at the
same station. In spite of these limitations it is obvious that the N'Dama
is an extremely small breed as compared to the Holstein, but with the
present data it cannot be determined how much of the difference in size
of the N'Dama and Holstein is genetic.

1 Professor of Genetics, Department of Dairy Science, University of Illinois,
on assignment at Njala University College, Njala, Sierra Leone under the Univer-
sity of Illinois/USAID contract afe-132, June-July, 1965, and in cooperation with
the Sierra Leone Ministry of Agriculture and Natural Resources (Agriculture
Division).

* Numbers in parentheses refer to references listed on page 39.

BULLETIN No. 724 [April,

Table 1 . — The Average Live Weights and Measurements
of N'Dama Cattle and University of Illinois Holsteins

Males

Females

Characteristic Source

1
year

2
years

Matu-
rity

1

year

2
years

Matu-
rity

Live weight (kg.) (a)

136

220

363

138

151

238

Length from shoulder point
to pinbone (cm.) (a)

181
84

91

273
300

102

414
419

114

176
81
310

84

271
234
519

91

414
353
596"

104

Height at withers (cm.) ... (a)

$

Heart girth (cm.) (a)

96

96
85
104

116

115

107
96
106

140

126

110
108
115

165

95
129

96
84
94
117

119

113
151

102
95
109
132

125

124
154"

106
107
112
136e

147

(«)

142

156

173

122
153

143
188

164
195"

" N'Dama cattle at the Musaia Animal Husbandry Station in Sierra Leone (13).
b N'Dama cattle at Bamako, French Sudan (25).
c N'Dama cattle at Mirankov, Ivory Coast (13).
d University of Illinois dairy herd (29).
e Four years of age.

It is believed that the N'Dama originated from cattle that accom-
panied Berber migrants from southern Morocco to the "Futa Jallon"
plateau in French Guinea (13). The N'Dama has since spread to the
surrounding areas and has interbred with the Zebu cattle of the sub-
saharan savannahs and the small shorthorned cattle of the coastal areas.
Doutressoulle (6) reported that the N'Dama increased rapidly in the
periods following the rinderpest epizootics of 1890-91 and 1918. At
these times the N'Dama replaced herds of other types in Senegal and
the French Sudan which had been decimated by rinderpest.

The N'Dama cattle are found in a belt approximately parallel to the
equator and stretching from the Atlantic coast in Senegal and Guinea
to the Borgou district in northern Dahomey. The northern and south-
ern limits are approximately at latitudes 14° N and 8°N. The northern
limit is closely aligned with that of the tsetse fly area, and, consequently,
with the southern limit of the Zebu cattle of the more open country to
the north.

A number of widely different estimates have been given for the
cattle population in Sierra Leone ranging from 250,000 to 400,000 head.
No reliable estimate is available because no census of the cattle popula-
tion has been made in Sierra Leone and because there is a constant mi-
gration of cattle in and out of Sierra Leone across the Guinea border

1967] N'DAMA CATTLE IN SIERRA LEONE 5

along the north and northeast boundaries. A conservative estimate for
the cattle population of Sierra Leone, based on generalized estimates
made by government officials, agricultural officers, and veterinarians, is
that there are approximately 250,000 head of cattle in Sierra Leone with
approximately 150,000 in the principal cattle raising area, the Koin-
adugu district in the northern province of Sierra Leone (26).

Three tribes inhabit the Koinadugu district: the Yalunkas in the
north, the Kurankos in the south and southwest, and the Limbas in
the west and southwest (22). The Yalunkas are along and north of the
Mongo River, the Kurankos are along the Seli and Bagbe rivers, and
the Limbas are south of the Mongo and west of the Seli. The Fula
cattle owner is mainly found in Yalunka country, while a few are in
Kuranko and Limba country.

Cattle production in Sierra Leone is plagued with many diseases and
pests. Diseases such as anthrax, rinderpest, contagious bovine pleuro-
pneumonia, blackquarter, red water fever, hemorrhagic-septicemia, calf
diphtheria, brucella abortus, and trypanosomiasis are said to be wide-
spread. Ticks, liver flukes, and worms are prevalent. Further, there
are a number of predators such as leopards and pythons that prey on
the younger animals.

Currently there are neither adequate data nor unequivocal informa-
tion about the true state of affairs concerning cattle disease and parasite
infections among the N'Dama cattle in Sierra Leone. Most animal hus-
bandmen and veterinarians in Sierra Leone say that diseases and para-
sites are widespread; but the actual incidence, the importance of the
several infections, and how such infections influence the economy of
cattle raising remain largely a matter for further investigation and ap-
praisal. A rather general survey (23) of animal diseases in Africa was
published in 1965 by the National Academy of Sciences National Re-
search Council.

The cattle must endure serious feed shortages in the dry season and
late rainy season. The year is divided into a rainy season, April through
October, and a dry season, November through March. The harmattan,
a dry northeast wind, can be expected from December through Febru-
ary. There is no storage of feed during the period when the vegeta-
tion is succulent, nutritious, and plentiful; thus, the cattle have to en-
dure the late rainy season on old, lower-quality vegetation and the dry
season on a limited supply of vegetation. Mature animals at the Musaia
station have lost as much as 200 pounds during the dry season, and some
young animals have weighed no more at 18 months than at 6 months
after having been weaned at 9 months and enduring a dry season on
their own.

6 BULLETIN No. 724 [April,

The vegetation is derived guinea savannah with fire-resistant tree
species. There are patches of high forest along the river banks and in
isolated pockets on steep hillsides that have avoided the main bush fires.
The main grass species are Chasmopodium caudatum, Hyparrhenis spp.,
Pennisetum subangustum, and Andropogan gabonensis.

According to Faulkner and Brown (7), probably the most serious
limitations besetting cattle production in this area are the result of the
social and nomadic practices of the Fula cattle owners. Murray (22)
has given a general description of the Fula cattle owners of Sierra
Leone, their cattle, and their methods of management. The Fula cattle
owners of Sierra Leone consist of nomadic Futa, Teliko, Kebu, and
Boway Fulas. They move in groups from one area to another in search
of fresh grazing and water for their cattle. They stay in one area from
two to three years after which they move their camp, starting the cycle
anew approximately every 20 years. All Fula cattle owners practice
arable farming on a larger scale than the local tribes. Rice, cassava, mil-
let, and maize are the main crops; however, the Fulas do not produce
or store feed for cattle for the dry season. The customary practice is
to burn areas of brush and grass in successive stages to produce feed
for cattle for the dry season. Burning begins with the end of the rains
and ends only with the arrival of the rainy season. It is a curious fact
that even after a prolonged dry season, burning off the old grass results
in new grass growth (26).

Cattle are a Fula's capital and wealth, and the relative wealth is in
general measured by the total number of cattle owned. Considering all
the obstacles that confront cattle raising in Sierra Leone, Roche (26)
concludes that the Fula is an excellent stockman and that many of his
practices are based on sound common sense. For many years the Fulas
have used a mixture of termite earth and loose salt to provide the
necessary salt for their cattle. The Fula knows good animals and is
hesitant to sell good females. He is always ready to sell males that are
not needed, if he can obtain a reasonable price. Further he sells the
females that do not produce calves or that appear unable to raise good
calves.

After the excess males and unproductive females are sold, the re-
maining animals in a Fula's herd are allowed to mate randomly. By sell-
ing the unproductive females, the Fula is fostering some selection for
female productivity. The Fulas are often placed in a disadvantageous
position, however, since Freetown is in general over-supplied with cattle
and there is no alternative in Freetown but to sell their animals to the
local butchers. There is an urgent need for the establishment of an
equitable cattle marketing system.

1967] N'DAMA CATTLE IN SIERRA LEONE 7

In 1952 the government of Sierra Leone began developing a plan
for settling the cattle owners (22). This plan has been implemented
and is being met with reasonable success. If the cattle owners are
settled, it should be easier to establish better health, feeding, breeding,
and other husbandry and management practices. The cattle settlement
scheme should also help establish a dependable cattle market for the
Fula cattlemen and a regular supply of meat for markets of the popula-
tion centers, such as Freetown.

The Musaia Animal Husbandry Station

Soon after World War II plans were initiated for establishing an
animal husbandry station near Musaia, in the Koinadugu district of
northern Sierra Leone. The Musaia area has a dense cattle population.
Work was begun in 1946 on establishing the station; by 1948 the station
was completed, and cattle were moved there from the Teko Veterinary
Station.

The mean annual temperature at Musaia is approximately 26.0° C.
with a mean low in December and January of 24.4° C. and a mean high
in March and April of 28.5° C. The mean annual relative humidity is
approximately 82 percent, with a mean low of approximately 76 percent
in February and a mean high of approximately 89 percent in September.
Of more importance to the cattle industry is the annual rainfall, the dis-
tribution of which is shown in Table 2 for 1952 through 1964. Decem-
ber, January, and February are definitely dry months, while March has
an average rainfall of only 1.4 inches, which is not enough to initiate
growth of grass. With a definite dry season and no storage of feed the
cattle must endure rather rigorous conditions for 4 or 5 months of the
year.

The station has an area of approximately 2,500 acres, is enclosed
in a well-built barbed wire fence, and is divided into blocks of approx-
imately 200 acres, each set off by sturdy barbed wire fences; there are
a number of smaller pastures. The topography is hilly: the valleys at
the Musaia station are 1,000 to 1,500 feet above sea level, while the hills
rise 2,500 to 3,000 feet above sea level.

The station was established to serve as a research station and as a
vehicle for demonstrating good animal husbandry practices. There is
evidence that in its relatively short life the station has had a marked
effect on the Fula cattle owners. Gamotox and Phenothiazine have been
distributed by the station to cattle owners, and station personnel have
demonstrated the use of bloodless castrators (22, 26). After having
seen the better grazing afforded by pangola grass on the lowlands and

BULLETIN No. 724

[April,

H ^Ooot^oor— oooot^-ooooooooio »~-
O :£<-£«^^ C!S«S «<5<POO OO

Q

<6

$ O

»H 1-1 i-H CS •

O ••-' oo *^ \o oo ~ \o - - -

o

be

3

0
JQ

M

fSTHi/5r*5 OOOO'— i

^ ^ ^ i

E

OroO-cf'^-it^t^p^iN. oo

g IT) TJ< Tf *O ~

O

I f*5 f5 ^

> *-i T}< oo

"" JB S

- OOOm^OO ON
_^ r* i/Ti ^ti on c^j ^t« «— i vn —

.E rt
"p

— ^H I ^ O CN

• PCI^P'— lOOOOOOOi—
C O^O'-iOOioOOOOOO
CM

Jj)

J3
.O

3

'5.

U
^

1967] N'DAMA CATTLE IN SIERRA LEONE

Puerana and Stylosanthes on the uplands at the Musaia statin, the
Fulas have shown interest in acquiring better grazing (26).

In its role as a research institution, the station set out in 1^48 to
determine the possibilities for milk production and beef prediction
using N'Dama cattle. As a consequence, a milking herd and a beef
were established (12). Prior to this, in the early 1940's, a milking
had been established at the Teko station to investigate problems coi-
nected with milk production (12). The 55 animals in this herd wer»
transferred to Musaia in 1948, and these animals constituted the milk
herd; shown in Table 3 are the average milk production figures for this
herd. It was indicated in the Jones report (12) that milk from N'Dama
cows had an average butterfat test of from 6.5 to 7 percent.

Table 3. — Milk Production of N'Dama Cattle at the Musaia
Animal Husbandry Station in Sierra Leonea

Year

No.
cows
milked

Ave.
no. cows
in milk

Ave. length Ave. milk yield
of lactation per lactation
(cays) in pounds

1944

... 26

8
9
8

9
10

10

11

12
17

152
203
337

294
285
263

237
197
136

390

722
1,077

1,108
1,225
1,381

1,154
927
805

1945

16

1946

18

1947

18

1948

. . 21

1949

19

1950

18

1951

21

1952 . .

28

• These data were taken from a report submitted in 1953 by T. S Jones to the Ministry
of Agriculture of Sierra Leone (12). For the years 1944-1947 the cows were at the Teko station,
and were moved in early 1948 to the Musaia station.

In general, milk production was low; cow 33 produced 2,521 pounds
in 210 days and cow 37 produced 2,516 pounds in 322 days for two of
the highest lactation yields. When suckling was not allowed at the start
of milking, there was difficulty in getting cows to let down their milk.
During part of the dry period supplemental feeding with concentrate
gave some increases in milk yield. In 1953 the milking herd was dis-
continued as such because of low milk production, and the cows were
made a part of the beef herd. The average 305-day lactation yield (4)
of the 74,001 cows on DHIA test in Illinois in 1964-65 was 11,911
pounds of milk and 458 pounds of butterfat and is quoted here as a
bench mark to help the reader understand that the milk production of
the Musaia herd was low.

10 BULLETIN No. 724 [April,

Thi numbers of animals in the milk and beef herds from 1948 to
1953 -re shown below.

Year Dairy Beef Total

1948 48 9 57

1949 53 52 105

1950 59 60 119

1951 79 77 156

1952 130 99 229

1953 ... 219 219

Of the 219 animals in 1953, there were 104 cows, 53 heifers, 55 bulls
and bull calves, and 7 oxen. By the summer of 1965 the herd contained
approximately 550 animals, approximately half of which were cows.

The Beef Herd

The beef herd is kept in groups of approximately 25 cows each; in
1965 there were approximately ten such groups. One man is assigned to
each of the ten groups, and he is directly responsible for the care, health,
and well being of the cattle in his group. These men are astute cattle-
men, generally Fulas, and they literally live with their cattle (26).

There is a second labor force of approximately 60 men concerned
with building fences, preparing land for seeding improved pastures,
weighing cattle, helping treat cattle for worms and ticks, and aiding in
the routine vaccination for anthrax, rinderpest, hemorrhagic septicemia,
and blackquarter. During the periods of clearing land for new pastures
as many as 200 men may work with this second labor force.

The calves are weaned at approximately 8 to 9 months of age, and
the bull and heifer calves are separated and kept in heifer and bull pas-
tures. There are usually three bull and three heifer pastures so that
young animals of widely differing ages are not kept together. The
heifers are bred so as to calve for the first time at approximately 3 years
of age. The bull calves are kept until they are approximately 3 years
old, at which time the larger ones are chosen and kept for future sires,
and the smaller ones are slaughtered and sold for meat. Many of the
definitely inferior bull calves are disposed of prior to 3 years of age.

In general there is no supplemental feeding during the dry season;
however, the Jones report (12) indicates that in the most severe drouth
years there was some supplemental feeding of a grain mixture. In other
years silage was made on an experimental basis, but the cattle were most
reluctant to eat the silage even though pasture was very limited and salt
and molasses were added to the silage (26).

The cattle at the Musaia station are watched closely by the Fula
herdsmen, are given excellent medical care, have ample grazing most of

1967}

N'DAMA CATTLE IN SIERRA LEONE

11

/

the year, and are protected from worms, ticks, and wild anin^ls. Ex-
cept for the shortage of feed in the dry season the husbandry is good.

Age at first calving

Shown in Table 4 are the ages at first calving for the N'l^ama cattle
in the various families. The average age at first calving for jtll families
was 39.4 months. The lowest age at first calving was 33.2 months for
the R family while the highest was 48.0 for the J family, For those
cows that calved, the average number of calves per cow wss 3.69. The
average age at first calving has been reported (10, 13) as 42.5 and 36 to
42 months, respectively. The average age at first calving for dairy cattle
in the United States is 24 to 27 months. At present, beef cattle under
western range conditions are being bred to calve at 2 yeaB of age.

Sex ratio

In Table 4 it is shown that of 1,269 calves born to 3H cows, 561
were males, 601 were females, and the sex of 107 was noi designated.
Thus of 1,162 calves, 48.3 percent were males and 51.7 percent were
females. This sex ratio does not differ significantly from a 50-50 ratio
(x2 = 1.38, 1 d.f.). Of 1,234 calves born in the Universitr of Illinois

Table 4. — Age at First Calving, Number of Calves, and Sex Ratio by Families

Family

No. cows 1
calving
(age known)

Vge at first
calving*
(months)

Total no.
cows
calvingb

No.
calves

No.
male
calves

No.
female
calves

^o. of
mknown
sex0

No. calves
per cow
calving

Main . .

46

39.3

125

508

207

229

72

4.06

B

. 25

40 6

60

285

133

121

31

4.75

A

4

42 3

4

16

7

8

1

4.00

C. .

10

39 7

10

53

20

33

0

5.30

D
E. .

... 11
6

35.3
44 2

11
6

41
30

19
14

21
16

1
0

3.72
5.00

G. . .

3

34 7

3

16

10

6

0

5.33

H

10

45 2

11

48

17

31

0

4.67

J.

9

48.0

9

33

16

17

0

3.67

K. .

45

38 1

45

104

51

51

2

2.31

L...

7

41 7

7

25

12

13

0

3.57

M.

7

45 7

7

23

15

8

0

3.29

N
R. .

... 8
. 22

38.8
33 2

8
22

19

40

8
20

11
20

0
0

2.38
1.82

S...

7

37 4

5

5

1

4

0

1.00

T. . . .

5

34 6

5

5

3

2

0

1.00

U. .

6

44 8

6

18

8

10

0

3.00

Total

231

39 4

344

1 269

561

601

107

3.69

• The birth dates of many cows in the original Main and B families were not known; thus some ages
at first calving were not known.

b Even though age at first calving was not known, the sex of the newborn calves was recorded; thus the
discrepancy between columns 2 and 4.

c In the early years the sex of some calves was not recorded.

12 BULLETIN No. 724 [April,

dairy csttle crossbreeding herd, 642 or 52 percent were males and 592
or 48 pecent were females (16). This sex ratio was not significantly
different from a 50-50 ratio (x2 = 2.03, 1 d.f.). Further, a chi square
test indicated that the two sex ratios were not significantly different
(x2 — 3.3S, 1 d.f.) ; however, in most European breeds there are more
males thar females at birth.

Calving interval

Shown klow is the distribution of calving intervals.

Intervals No. cows Intervals No. cows Intervals No. cows

in days calving in days calving in days calving

299 or less 14 420-449 53 570-599 30

300-329 64 450-479 42 600-629 36

330-359 151 480-509 37 630-659 21

360-389 184 510-539 38 660-689 19

390-419 106 540-569 52 690 or 79

greater

The mem calving interval was 467 days, which is high compared
with the msan calving interval for both beef and dairy cattle in the
United Stales (approximately 13 months or 390-400 days). The calving
intervals for the Musaia N'Dama ranged from one of 267 days for cow
153 to one of 1,062 days for cow D17. In general the calving interval
was approiimately two months longer than that for European breeds
and slightV shorter than that reported for Zebu breeds. The mean
square associated with variation between cows was 21,635, while that
associated vith variation between intervals of the same cow was 25,001 ;
the degrees of freedom were 262 and 663 respectively. This finding is
similar to icsults generally found for European breeds.

Age at disposal and of animals in the herd

The aveiage age at disposal for males was 29.0 months while that of
females was 32.4 months (Table 5). For many of the younger families
the average cge at disposal is quite low. This reflects the fact that most
animals in th^se sire families were born rather recently. This can also
be seen from the average age of live animals in these families.

The average ages of live animals in the herd were 22.3 and 46.2
months for miles and females respectively. The females in dairy and
beef herds in Hie United States have an average age of approximately
60 months; thus, 46.2 months is low for the average age of females. On
the other hand 22.3 months is much higher than the average age of
males in herds in the United States, as most male cattle, both dairy and
beef, are sold fcr meat by 15 months of age.

1967}

N'DAMA CATTLE IN SIERRA LEONE

13

Table 5. — The Average Age in Months of Males and Females
in the Herd and at Disposal or Death

Family

No. animals
listed

No. animals

with birth

and disposal

dates

d1 9

Average age

at disposal

or death*

(months)

No. animals
still alive

Average age of

live animals

(months)

Main 156 64 76 26.6 51.4

B 69 33 24 46.7 57.8

A 15 94 37.6 36.0

C 42 25 10 39.9 30.8

D 39 19 10 33.6 32.5

E 14 45 32.8 32.6

F 5 0 5 .... 3.8

G 8 3 1 32.7 1.0

H 27 12 7 33.9 39.7

J 22 11 4 26.0 48.3

K 176 66 23 27.8 14.1

L 21 88 29.6 27.0

M 27 8 10 12.6 20.9

N 40 10 6 30.8 8.1

P 10 63 15.8 8.7

Q 2 0 2 .... 13.0

R 123 29 15 26.8 12.9

S 36 10 1 37.1 7.0

T 87 11 7 19.7 13.0

U 43 18 17 15.3 16.4

DA 72 1 4 17.0 3.8

DB 40 5 1 10.0 1.0

RA 52 23 8.0 2.0

RB 53 0 1 16.0

KA 35 24 1.0 3.3

KB 31 22 3.0 .0

TotalorMean 1,245 358253 29.0 32.4

» Includes all animals on which age at death or disposal was known.

Death losses

Of the 1,245 animals listed in Table 5, 87 died before 2 years of age,
52 were sold or culled, and 13 were reported missing and presumably
lost to predators. Thus, by 2 years of age, 152 animals or 12.2 percent
were not available for breeding purposes. This is comparable to losses
from similar causes in the United States (5). No record of losses be-
cause of failure to breed was available. The losses from death and cull-
ing appeared to be randomly distributed according to families and sex.

Body weights

All animals in the beef herd were weighed at birth and on the first
day of the month for as long as they lived. Shown in Table 6 are the
numbers of progeny in the 26-sire progeny groups on which weights
were available and thus included in the weight data analysed. The first

4
1
0
0
2
1
0
0
0
0
24
0
2

12

0

0

32

9

31

2

32
20
20
19
20
12

12

1!

I

7
8
4
0
4
8
7

53
5
7

12

1

0

47

16

38

6

35

14

27

33

9

15

243 391

14 BULLETIN No. 724 [April,

Table 6, — The Number of Progeny in the Sire Groups at Various Ages*

Sire

Birth

6 12 24 36 48

months months months months months

Unknown . .1

73

68

59

41

30

24

95 .

23

8

15

14

22

7

137

19

14

14

12

7

6

15C. .

26

26

26

20

15

14

243..
*^

. . . . 18

16

13

14

11

8

#5

112

107

105

74

54

12

320 \

31

30

29

29

25

15

B33 \. .

13

13

11

12

9

5

B37. .

44

41

40

37

19

15

B46 i

39

38

33

29

21

13

B122

23

19

18

14

8

7

B164. .

36

34

34

33

16

2

Cl

38

37

35

32

19

4

C2. .

19

18

19

15

13

9

El 1

159

150

145

119

86

38

156

7

6

6

6

2

3

152 .

3

3

3

2

2

1
L9

77

77

58

30

13

D31

59

49

45

22

C7

6

6

6

RIO i

42

32

28

D34..

33

31

24

R9 .

.... 40

28

27

K71

. 24

6

2

102

4

2

K116 1

18

12

Number of sires
in analysis

26

26

24

19

18

16

Total A ...

. . 986

871

795

555

372

182

» These numbers include only those animals for which weights were available.

group, labeled unknown, is composed of progeny whose sires were not
known. There are a number of blanks in the lower right hand corner of
the table because the progeny of these sires were born recently and have
not reached the older ages. Further, many of the sires near the bottom
of the table have many more progeny, but which were too young to have
weights beyond birth and 3 or 4 months, and thus were not included at
all. The figures in Table 6 cannot be used as a means of comparing the
viability of calves of the different sires, as many calves were not old
enough to have weights at the older ages.

Shown in Tables 7 and 8 are the numbers born in the different years,
in the different months of the year, and of the two sexes. Again, these
figures cannot be used as a means of comparing the relative viability of
calves born in the different months or different years unless those too
young to have weights at the older ages are deleted. By observing the
numbers born in the different years it is apparent that the number in the

1967] N'DAMA CATTLE IN SIERRA LEONE

Table 7. — The Numbers of Calves Born in Different Years8

15

Year

Birth

6
months

12
months

A

nwnths

36
months

48
months

1949..

19

15

11

14

14

12

1950

18

11

11

11

76

9

1951

21

14

19

18

18

4

1952

20

16

18

18

14

12

1953

28

27

28

26

13

11

1954

54

47

39

32

21

14

1955

. . . .53

51

45

40

25

20

1956

38

38

38

32

28

16

1957

69

63

62

58

38

29

1958

62

53

53

32

19

13

1959

19

18

14

3

2

1

I960

82

77

76

7)

61

28

1961

91

91

87

81

79

13

1962

118

115

112

194

24

1963

160

160

158

15

1964

134

75

24

Total

986

871

795

555

372

182

* The numbers include only those animals for which weight? were available.

Table 8. — The Numbers of Calves Bon in Different Months
of the Year and of the Two Sexesa

Birth

6
months

12
months

24
months

36
months

48
months

Month of birth
January

. 114

106

107

80

60

24

February

86

73

81

63

50

20

March

40

40

34

26

21

16

April

48

46

41

33

21

13

May

115

100

93

78

60

37

June

34

28

23

20

\b

10

July

13

11

10

9

6

4

August

76

72

50

26

13

4

September

102

90

75

38

21

5

October. .

120

94

82

38

19

11

November

Ill

93

85

54

35

13

December

127

118

114

90

51

25

Total

986

871

795

555

372

182

Sex of calf
Male

. 478

435

692

278

165

36

Female

508

436

403

277

207

146

Total

986

871

795

555

372

182

The numbers include only those animals for which weights were available.

16 BULLETIN No. 724 [April,

herd had increase* approximately eightfold from 1950 to 1964. The
figure for 1964 doe\ not include all those born in 1964, as those born in
late 1964 would havVjhad only birth weights and 2 or 3 month weights
recorded ot the time ifie data were copied.

From Table 8 it i\ apparent that the majority of the cows calve in
September, October, November, December, January, and February.
In these 6 months, 66(\ of the 986 animals were born. The figures for
the months oi November and December are lower than they would be
if all calves born late in 1964 had been included. The unexpectedly
high number oi births occurring in May is probably the result of a
management practice (12) instigated in the early fifties whereby an
attempt was made to breed cows to deliver at the beginning of the wet
season. This practice was abandoned after a few years. Most of the
Fula cattlemen have their cows calve during the period from September
through February and mainly in December, January, and February.

The numbers of males and females at the different ages as shown
in Table 8 afford an interesting bit of information. The numbers of
males and females do not differ significantly until 36 months of age.
At the Musaia station, males are generally kept until 3 years of age
before they are slaughtered or used as sires. It appears that most
N'Dama in Africa are not slaughtered until after they reach 3 years of
age (10, 11, 24). It is aft«r 3 years of age that most of the culling of
unwanted males occurs; thus, not until 4 years of age does the number
of females greatly exceed the number of males.

Tables 6, 7, and 8 proride another bit of interesting information.
Even though there are 986 calves with birth weights, there are only 182
with weights at 48 months of age. To accumulate a large volume of data
on cattle at older ages requires that a large herd be kept for many years.

To describe the weights of the animals, linear model I was used.

I. Y,,kln = U + B, + A, + Mk + S, + Eijklm

Yijkim is the weight at a given age of the mth calf, of the 1th sex, born

in the k* month of the jth year and by the ith sire.
U is the least squares mean.

Bi is the random deviation associated with the progeny of the ith sire.
Aj is the fixed effect associated with calves born in the jth year.
Mk is the fixed effect assoc&ted with calves born in the kth month of
the year.

Si is the fixed effect associated with calves of the 1th sex.

is the random deviation associated with the mth calf of the 1th
sex, born in the kth month of the jth year and by the ith sire.

1967}

N'DAMA CATTLE IN SIERRA LEONE

17

Table 9. — The Analyses of Variance of Weight at Ten Different Ages

Birth

3 months

6 months

9 months

12 months

n

DF

MS

DF

MS

DF

MS

DF

MS

DF

MS

Sex of i
Year oi
Month
Sires .

~a!f

1
15
11
25
933

1,781**
89**
107**
44*
25
.225
.475

1

15
11
25

878

13,404**
3,524**
2,813**
843**
512
.242
.492

1

15
11

25
818

25,068**
11,460**
8,943**
2,142**
944
.357
.597

1

15
11
23
745

46,216**
8,963**
7,819**
2,085*
1,162
.398
.631

1
15
11
23

744

62,488**
9,112**
5,882**
2,660**
1,186
.360
.600

birth..,
of birth

Error .

R

18 months

24

months

30 months

36 months

48

months

•''

DF

MS

DF

MS

DF

MS

DF

MS

DF

MS

Sex of c
Year of
Month
Sires. .

:alf . .

1
14
11
20
587

11,264*
21,566**
14,049**
2,464
1,733
.417
.646

1
14
11
19
510

5,571
22,466**
6,626**
2,200
2,128
.350
.592

1

13
11
18
429

6,108

27,823**
22,253**
2,018
3,002
.380
.616

1
13
11
17
329

62,170**
12,109**
3,712
2,113
2,891
.319
.565

1
12
11
15
142

322,176**
7,495*
2,318
1,376
3,310
.620
.787

birth...
of bfrth

Error .

R2* .

R

* Significant at the .05 level of probability.
** Significant at the .01 level of probability.

• RJ =: Fraction of variance accounted for by model 1 (exclusive of error).

Shown in Table 9 are the least squares analyses of variance for
Weight at ten different ages. As can be seen from the R2 values in the
;next to last row of Table 9, model I has accounted for 22.5 to 62.0
:rcent of the variance in weight at the different ages. The R2 value at
months of age is markedly higher than those at the younger ages and
|is probably a result of the severe culling of males between 36 and 48
months on the basis of weight. This culling has brought about an ex-
tremely large difference between males and females at 48 months and
thus an extremely large mean square for sex. The R values, which are
the correlations between actual weights and weights as predicted by
model I, range from 0.475 to 0.787; thus model I has been effective in
explaining variations in weight at the various ages.

The least squares constants for sex of calf and month of birth are
shown in Table 10 along with the least squares means, while the least
squares constants for year of birth are listed in Table 11. These con-
i stants are useful in finding the means of various categories. For ex-
ample, the mean birth weight of all male calves is 36.2 + 1.4 = 37.6
pounds while that for all female calves is 36.2 — 1.4 = 34.8 pounds.
,• Males are 1.4 —( — 1.4)= 2.8 pounds heavier at birth than females.
One further quality of the least squares means and constants for males
\ and females is that they have been adjusted for the fixed effects of

%

co

13

C
O

3=
D

u

X

o>

CO

o

U

c
o

Q)

*

O

3

cr

CO

j>

JQ
O

•%

^=
c
s

1 1

* *
•* oo

i i 1 7 i

• *-H 10 ON OO OO t-*

I I

10 \o oo oo

*— 1 i rH CS

I I

I I ~ ' I I I I I

IO \O OO OO VO O\ ••* O >O 1/5 IT5 IO

-

««•= °S

III •§!

ao. v « c

<*H>*-. V X to °

°°£-si^
•3-5. a 8^

EOT O
c " u
^"Rvi'" « u

« « •. S g."d

rt rt.O rt S h

cx>bog_.

CQ

•s

o

<D

•o
3
o

»HOOOfO
OO CS I I

I I

i - i>: _; >-,

I I

1 1 1

I I

'-' t^ oo oo t—

CNCS

I I

I I

o
u

"b <Mt-»»-l~H OOl^OO
O

c t^* oo ^o oo **) CN **o ^^ f^ ^"^ oo ^^

CO Ov

o " """ ' ' '

0)

|£

- » « * * *

O\O\O\CS OO^^ OoOOOO

jb
« o-o

»H TH CS 00

to b
'43 vo»-H^Ht--*orf<Ti<in-^'rvo^j<T^r^r'^' o o

—•— . «

o ** ** F ? ^ 3

Srti OO ^—i O ^rOOO rt*^HCSO ON ON W} OO ^ *2 . C o

n « « o

00 00 rj< O\ CN •.-! 10 •* f*5 •<* m irjprii-.es ^-^'glnin
CSCS || || CNCS | |

v v o o

•fl.13 Q.

OO OO O O rtrt""rtw
P3 J3 oOTtiOOOrOCS^S^-H^H'OO'^H'l'OOTtiiO 'c'SpSS

00 60 MJ r/5

- pf* rf- . i , __. r^s ^-i ••^•'•tr!^^

' I

* *

ir>ioir>lo^3_ — O\OVO\ON

20 BULLETIN No. 724 [April,

month and year of birth and the sampling variation between sires. The
mean birth weight of calves born in 1957 was 36.2 + 3.1 = 39.3 pounds
while that of calves born in 1955 was 36.2 — 3.3 = 32.9 pounds. Those
born in 1957 were 39.3 — 32.9 = 3.1 — (—3.3) = 6.4 pounds heavier
than those born in 1955. The differences between year of birth have
been adjusted for the fixed effects of month of birth and sex of calf and
the random variation associated with sires. The least squares means
and constants in Tables 10 and 11 can be used to find the adjusted
means of a variety of subclasses. For example, the mean birth weight
of male calves born in January of 1957 is 36.2 + 1.4 + (— 0.1) + 3.1
= 40.6 pounds.

As indicated in Table 9, the effects associated with sex of calf were
significant at all ages except 24 to 30 months. As can be seen from the
least squares constants in Table 10, males are 2.8, 7.8, 11.0, 15.6, 18.4,
8.6, 6.6, 7.6, 28.2, and 128.6 pounds heavier than females at birth and
3, 6, 9, 12, 18, 24, 30, 36, and 48 months of age respectively. The dif-
ference between the sexes increases up to 12 months of age and then
decreases to 24 and 30 months. The least squares constants at 36 and
48 months show a marked difference between the average weights of
males and females. It is thought that much of this difference is a result
of more severe culling of males than females at these two ages. In
general, the least squares means and effects of sex of calf agree with
means reported in other studies (10, 11, 13, 24, 25).

As shown in Table 9, the effects associated with month of birth are
significant at all ages except 36 and 48 months. The effects of month
of birth on weight at later ages is mainly a manifestation of the stage
in the wet and dry weather cycle in which an animal reaches a given age.
For example, those animals born in March, April, and May reach a year
of age after having been weaned during the dry season and then sur-
viving the dry season. The constants in Table 10 indicate that these
animals are 14 to 20 pounds lighter than the mean at 12 months. Those
animals born in July, August, September, and October are from 11 to
30 pounds heavier than the mean at one year. If the constants for 18
months are observed, it is seen that those animals born in July, August,
September, and October are lighter than those born in March, April,
and May. If a breeder wants to sell his cattle at 18 or 30 months of
age, it appears that he should have his cows calve in December, January,
February, or March. On the other hand, if he wants to sell at 24 or 36
months, he should have them calve in July, August, or September. The
effects of month of birth on weights at later ages are mainly a reflection
of the nutritional cycle through which the calves themselves have re-
cently passed (11). The effects of month of birth on birth weight are

1967] N'DAMA CATTLE IN SIERRA LEONE 21

likely manifestations of the nutritional cycle through which the dam
passed while the calf was in utero.

The mean weights for those calves born in February and September
and having weights every month up through three years are shown in
Fig. 1. Those calves born in February grow well until the eighth
month, which is October. At approximately 8 to 9 months the calves
are weaned, and they start the dry season with no supplemental feeding.
The mean weights from the 8th through the 14th month of life, or from
October through the following April, are 211, 211, 214, 221, 215, 218,
and 223 pounds respectively. These calves have gone six months with
essentially no gain in weight. From April to the following October, the
calves gain approximately 100 pounds; then during the second dry sea-
son through which they live they gain only 20 pounds. During the next
wet season they gain another 100 pounds. Before those calves born in
February reach 36 months of age they have gone through two periods
of 6 months each of essentially no gain in weight. On observing the
gains up to 36 months of calves born in September, it is seen that they
go through two periods of 8 months each of essentially no growth. The
constants for month of birth in Table 10 agree closely with the plotted
curves of Fig. 1 even though they are based on different numbers.

Just why the effects associated with month of birth failed to be
significant at 36 and 48 months is not known. It could be that by 3 and
4 years of age the animals have been through a sufficient number of
nutritional cycles caused by the wet and dry seasons and exposed to
other debilitating environmental factors to such an extent that month of
birth becomes relatively unimportant as a source of weight variation.
It might also be that culling on a weight basis has partially removed
some of the variation associated with month of birth.

The mean squares associated with year of birth (see Table 9) are
significant at all ages included in the study. Three likely causes of vari-
ation between year of birth are the differences in the severity and ex-
tent of the dry periods (thus more seriously limiting the pasture
available in some years than in others), differences between years re-
sulting from improved pastures and other management practices, and
larger weights resulting from genetic improvement. In observing the
least squares constants in Table 11, there appears to be no evidence for
an increase in weight from the early to the late years. At the older ages
the constants associated with year of birth are a conglomerate of the
combination of genetic and environmental factors affecting the calf in
utero and from birth to the specified age. Thus at 24 months of age
calves born in 1949 were 108 pounds above average; this 108 pounds

22

BULLETIN No. 724

[April,

SONHOd Nl 1H9I3M

t> V

x A
HH

1967] N'DAMA CATTLE IN SIERRA LEONE 23

indicates that those calves born in 1949 enjoyed a favorable series of
environmental occurrences from birth to 2 years, or were themselves
a rather select group of calves, or were fortunate in both respects.

To determine if there were distinct linear trends in the weights of
calves born from 1949 through 1964 the regressions of the least squares
constants on year of birth (written as the numbers 1 through 16) were
calculated for weights at birth and 12, 24, 36, and 48 months of age.
The regression coefficients are shown in Table 12. The regression for
birth weight on years indicates that birth weight has increased approxi-
mately 0.2 pound per year over the 16 years. All other regression coeffi-
cients are negative. Except for the extremely large positive constant
associated with the year 1949, no other obvious trends exist to explain
the negative regressions. If the constants in Table 11 for a given age
are plotted against the years from 1949-1964, it is apparent that the con-
stants for 1949 are unexpectedly large. This suggests that the cattle
born in 1949 and included in these data were either a select group, or
enjoyed a most fortunate sequence of environmental conditions, or
possibly both. After eliminating the constants for 1949, no consistent
trends associated with year of birth remained. There has been no con-
sistent increase in weight at a given age in the last 15 years.

Table 12. — The Regressions (b) of the Least Squares Constants
on Year of Birth and Their Standard Errors (a)

Age in months

Birth

12

24

36

48

b8

+ .22*

-3.1*

-4.4

-18.7**

-1.6

trb*

08

1 08

2 18

1.61

2.91

df.

. 14

14

13

12

11

* Significant at the .02 level of probabjlity.
** Significant at the .01 level of probability.

• b and <Jb are in pounds.

The size of the least squares constants in Tables 10 and 11 indicates
that before culling on a basis of fixed weight standards the weights of
all calves should be adjusted for sex and for month and year of birth.
For example, at 24 months of age those calves born in March are 34.6
pounds lighter than average while those born in August are 30.8 pounds
heavier than average. The average weight at 24 months is 359.7 pounds;
thus, those born in March are approximately 10 percent lighter than
average while those born in August are approximately 9 percent heavier
than average. To adjust for month of calving, the least squares con-

24 BULLETIN No. 724 [April,

stants in Table 10 can be used. For example, to adjust weight at 2
years, all those calves born in March should have 34.6 pounds added to
their weight and those born in August should have 30.8 pounds sub-
tracted from theirs. Such adjustments would yield weights similar to
those resulting from having all calves born in the same month of the
year. Adjustments for sex and year of birth can be accomplished in a
similar way.

The mean squares for sires in Table 9 were obtained assuming that
the sire effects were fixed. The effects associated with sires were sig-
nificant up through 12 months of age. After 12 months, the sire effects
were not significant in any case, and, in fact, at the last three ages the
mean square for sires was less than the error mean square. This sug-
gests that from 18 to 48 months factors are in operation which tend to
equalize the means of the progeny groups. Examination of the mean
weights for the progeny groups shown in Table 13 (which have been

Table 13. — The Adjusted Mean Weights for the Progeny Groups*

i

/

Lge in i

nonths

Birth

3

6

9

12

18

24

30

36

48

Unknown

. . 36

101

154

195

216

282

348

424

467

538

95

. . 40

89

127

166

194

243

315

393

459

542

137...

. . 35

110

191

235

254

289

345

430

484

567

159

. . 37

94

146

189

229

279

373

436

503

580

243

. . 38

105

179

220

248

318

376

437

478

535

325

. . 35

113

165

209

238

294

365

427

463

546

B20

. . 37

99

158

211

233

296

357

409

480

513

B33

. . 33

114

182

222

255

295

383

427

479

529

B37

37

117

169

217

245

288

364

423

491

560

B46

. . 36

105

159

196

235

295

367

441

485

559

B122

. . 37

105

150

196

215

278

352

417

473

551

B164

. . 38

118

174

207

233

294

359

413

459

S10

Cl. .

36

115

170

208

236

291

364

422

456

562

C2

. . 36

104

159

195

225

291

354

423

440

540

El

. . 36

113

169

208

235

294

367

427

464

S49

156

.. 35

108

175

208

215

279

368

443

477

Sfil

152..

40

102

143

211

236

272

365

384

480

L9 . . .

36

108

160

201

231

279

356

433

461

D31

.. 35

109

163

206

231

295

357

475

C7. .

39

104

162

195

200

269

RIO. .

37

108

165

214

245

308

D34. . . .

35

101

147

190

221

R9

35

115

161

199

217

K71

. . 33

102

153

207

242

102

36

83

109

K116

. 38

111

168

L.S. means'*. . .

36

106

160

204

231

287

360

426

471

546

Raw means. . . .

37

107

167

211

227

281

349

418

461

502

• All weights are in pounds.
b Least squares means.

1967] N'DAMA CATTLE IN SIERRA LEONE 25

adjusted for sex of calf and year and month of birth) makes it apparent
that some of the last sires used have some of the lowest means for a
given age. These sires have not been in service long enough to have
progeny older than 6 to 12 months; consequently, these sires are not
included at the older ages. The fact that some sires do not have progeny
at the older ages may be a cause of the relative decrease in the variation
between progeny groups at the older ages. If culling according to some
standard weight were practiced, this would tend to equalize the weights
of the sire groups. There was reference to standards of culling in
the Jones report (12), but whether culling according to set standards
has been routinely practiced is not known. If early in their lives the
progeny of a given sire were kept together but separate from the prog-
eny of contemporary sires and then assigned to pastures at random in
later life, this could help explain the significant variation between
progeny groups from birth to one year followed by the nonsignificant
differences at the older ages. It might also be that those animals still
living at the older ages are those that were able to survive the ravages
of a tropical environment, and variations in genotype for weight have
little chance to be expressed after the demands and ravages of the
rigorous environment have been met.

The constants for sex, year of birth, and month of birth shown in
Tables 10 and 11 can be used to adjust the weights, thus leaving only
the random variation between and within sires in the data. Such an
adjustment was done, and the adjusted means for sires are shown in
Table 13 while the between and within sire components of variance are
shown in Table 14. Estimates of heritability of weight at the different
ages can be obtained by using formula II.

II. h2 =

+•

In using formula II it is assumed that a\ is one-fourth of the additive
genetic variance plus a small fraction of the additive by additive
epistatic variance. Further, it is assumed that ov consists of three-
fourths of the additive genetic variance plus the dominance and
environmental variance and the remainder of the epistatic variance.
Thus, formula II is a fraction whose numerator is an estimate of
the additive genetic variance and whose denominator is an estimate
of the phenotypic variance.

In reality, <rl contains one-fourth of the additive genetic variance,
a small fraction of the additive by additive epistatic variance, plus
any environmental factors which tend to make the progeny of a
sire alike but different from the progeny of another sire. In general,

26 BULLETIN No. 724 [April,

Table 14. — Estimates of the Between (ajj) and Within (<?%,) Sire Components

of Variance, Standard Deviations (CTP), and the Paternal Half Sib (hi) and Regression

of Offspring on Dam (hi) Estimates of Heritability of Weight

Age in months

Birth

6

12

18

24

30

36

48

Between sire-DF

25

25

23

20

19

18

17

15

Within sire-DF

. . 933

818

744

587

510

429

329

142

ff\ .

. . 1.1

66

92

54

49

35

38

-5

<r\,

.. 24.6

944

1,186

1,733

2,128

3,002

2,891

3,310

ffn = v/ ai + <TW .

5.1

32.2

35.7

42.3

46 7

55 1

54 1

57 5

hf. .

.17

.24

.29

.12

.09

.05

.05

-.01

0"h .

.08

.10

.12

.08

.08

.10

12

15

h|.

.29

-.03

.10

.08

.05

.23

.38

<TJ,

.07

.08

.08

.10

.11

.18

.20

No. offspring —
dam pairs

. . 585

453

395

319

269

214

157

Expected genetic
gain hj (z/b) ap

..11

9 6

12 8

6 3

5 2

3 4

3 4

Expected genetic
gain h* (z/b) ffp. . . .

.. 1.8

-1.2

4.4

4.2

2.9

15.7

25.5

(z/b) : assumed to be 1.24.

op and expected genetic gains are in pounds.

such factors tend to make a\ larger than it should be. Certain acts
of man, such as culling, tend to equalize the progeny group means
while at the same time leaving unaltered, or changing only slightly,
the relative sizes of the variances within progeny groups. Thus,
using formula II often results in biased estimates of heritability.

The estimates of heritability resulting from using formula II, com-
monly referred to as paternal half sib estimates of heritability, are
shown in Table 14. To the extent that management practices allowed
the environmental factors to affect progeny groups at random, the
paternal half sib estimates are unbiased. It is likely that at the older
ages the animals are a selected group and differences between progeny
groups have been reduced. At the ages of 3 to 12 months it is possible
that the sire components are larger than they should be because of man-
agement factors being confounded with sires.

Also shown in Table 14 are estimates of heritability obtained from
the regression of offspring on dam. Before these estimates were de-
rived, the weights were adjusted for year and month of birth and sex
of animal by using the least squares constants of Tables 10 and 11. The
regressions were also derived on a basis of the variation between calves
of the same sex born in the same month and year, but these regressions
are not shown because they agreed so closely with those derived from
the adjusted data.

1967] N'DAMA CATTLE IN SIERRA LEONE 27

The paternal half sib estimates are relatively high at the younger
ages, but gradually become smaller at the older ages. Conversely the
regression estimates start out high, become small at the intermediate
ages, and then become large again at the older ages. All paternal half
sib estimates from birth to 12 months are significant, while none of the
estimates after 12 months is significant. The only age at which the
estimates are significantly different from each other is 6 months. The
difference at 6 months is probably related to the fact that the calves
have survived to this age mainly by suckling their dams. With the rela-
tively large standard errors of the estimates of heritability, an elaborate
interpretation of the significant difference would not be too meaningful.

The averages of the two estimates at birth, 6, 12, 18, 24, 30, and 36
months of age are 0.23, 0.11, 0.20, 0.10, 0.07, 0.14, and 0.21, respectively.
In general, heritability of weight at a given age for the N'Dama is
markedly lower than that found in most European breeds (14, 15, 16).
Weaning weight of beef cattle in the United States has a lower herita-
bility than birth or yearling weight (14, 15). This is in agreement with
the above averages at birth, 6 months, and 12 months.

From a study of the herd of White Fulani cattle at the Shika Stock
Farm in northern Nigeria, Foster (8) reported heritabilities of birth
weight of 0.19 ± 0.15 and 0.42 ± 0.23 respectively for the regression
of offspring on dam and the paternal half sib estimates. For weight at
2 years the estimates were 0.08 ± 0.12 and 0.69 ± 0.25 respectively.
The regression estimates are remarkably similar to those for the Musaia
herd, while it is probable that the paternal half sib estimates reported by
Foster are confounded with year to year environmental differences and,
if they are, are thus too large.

The expected genetic gain per generation resulting from selecting
for a single character can be expressed as follows :

III. AG = h2 (z/b) (7P.

where h2 is the heritability of the characteristic, b is the fraction of the
population that must be saved to reproduce the next generation, z is
the height of the ordinate where a vertical line truncates the top b per-
centage of the population, and ap is the phenotypic standard deviation of
the character. The term z/b is the number of standard deviations that
the mean of the selected group is expected to exceed the mean of the
population. Values of z, b, and z/b may be found in any table of the
areas and ordinates of the normal curve. Fig. 2 should help explain
the (z/b) <Tp part of formula III.

In Fig. 2, the mean of the selected group, X8, minus the mean of the
entire population Xp, is (X8 — Xp) = (z/b) <TP- The expected genetic

28

BULLETIN No. 724
Z

[April,

The amount by which the mean (X,) of the top b percent of a normal pop-
ulation exceeds the mean (Xp) of the entire population,
b = percent of population saved.

z = the point or ordinate where the line truncating the top b per-
cent cuts the normal curve.
<TP = the standard deviation of the population.
(X.-XP) = (z/b)<v (Fig. 2)

or breeding value of the selected group is Xgs = Xp + h2 (z/b) crp or it
is h2 (z/b) op above the population mean, Xp. If randomly drawn males
and females from the fraction b were mated, the resulting progeny
would be expected to exceed the mean of the parental generation, Xp,
by the amount, h2 (z/b) <rp.

Suppose now that we wanted to select the cattle at the Musaia sta-
tion for weight at one year of age. What increase in weight at one year
could be expected per generation of selection ? Heritability at one year
is estimated to be 0.29, and crp is estimated to be 35.7 pounds. Keep in
mind that the 35.7 pounds is the standard deviation remaining after
having adjusted the weights at one year of age for month and year of
birth and sex of the animal. Such adjustments usually increase the ac-
curacy of selection. In a population of cattle such as that at the Musaia
station it should be possible to perpetuate the herd by using only the top
5 percent of the males and the top 75 percent of the females for breed-
ing purposes. By looking in a table of areas and ordinates of the normal
curve, it can be found that the mean of the top 5 percent is 2.06 standard
deviations above the mean of the population, while the mean of the top
75 percent is 0.42 standard deviation above the population mean. Except
for sex linkage, males and females contribute equally to the next gen-
eration; thus the average z/b is (2.06 ± 0.42 )/2 = 1.24. Putting these
three values together, the expected genetic gain per generation is found
to be:

AG = h2 (z/b) (TP = 0.29 (1.24) (35.7) = 12.8 pounds

1967] N'DAMA CATTLE IN SIERRA LEONE 29

Shown in Table 14 are the expected genetic gains per generation for
various ages; an average z/b of 1.24 was assumed.

The next question of importance is the generation interval. The
average age at calving was 39.4 months and the average calving interval
was 15.5 months. To replace herself, the average cow would have to
calve approximately three times. Thus the average generation interval
would be approximately 86 months or 7 years. The gain per year would
thus be approximately 1.8 pounds for weight at one year of age.

Koch and Clark (14, 15) found heritability of yearling weight of
beef cattle in Nebraska to be 0.47 and 0.43 respectively and standard
deviations of 56.4 pounds and 56.7 pounds. Assuming a z/b of 1.24 the
expected genetic gains per generation are 32.9 and 30.2 pounds respec-
tively. Further, the generation interval is approximately 5 years; thus,
the expected genetic gains per year are 6.6 and 6.0 respectively. To say
the least, the expected genetic gain per year for the N'Dama under
Musaia conditions is comparatively small.

It seems that the average age at first calving could be reduced to 24
months instead of 39.4 months, thus shortening the generation interval
by 15.4 months. Further, it would seem that at least 2.5 months could
be taken off the average calving interval. By doing these two things the
average generation interval could be shortened by approximately 23
months.

Having cows calve at a younger age and shortening the calving inter-
val seem like inconsequential changes, but are they? From Table 12 it
can be seen that the average weight of N'Dama females at 2 years is
356.4 pounds while weights for Guernsey and Holstein females (Table
15) are 860 and 1,143 pounds respectively. Are the small size and old
age at first calving mainly a genetic characteristic of the N'Dama breed
or are they mainly a result of the general nutritional level under which

Table 15. — The Mean Weights in Pounds of N'Dama Females at the Musaia Station
and Holstein and Guernsey Females in the University of Illinois Dairy Herd*

Age in months
Birth 3 6 12 18 24 30 36 48

N'Dama 9 's (N). . 35 102 154 222 283 356 422 457 482

U.of I. Holstein 9 's(H). 89 216 379 683 939 1,143 1,185 1,278 1,313

U.of I. Guernsey 9 's(G) 65 150 301 551 707 860 900 967 1,050

H/N 2.54 2.12 2.46 3.08 3.32 3.21 2.81 2.80 2.72

G/N 1.86 1.47 1.95 2.48 2.50 2.42 2.13 2.12 2.18

•The number of Holsteins ranged from 150-170, while the number of Guernseys ranged from 89-110 at
the different ages. The numbers for the N'Dama are shown in Tables 6 and 7.

30 BULLETIN No. 724 [April,

the N'Dama is kept? Even if the generation interval is shortened sub-
stantially, the gain per generation is still small.

Comparisons of weights of N'Dama, Holstein, and Guernsey cows

Shown in Table 15 are the mean weights of females of three breeds
at different ages. The weights for the N'Dama are the least squares
weights of females derived from the means and sex constants of Table
10. These means are comparable to those reported in other studies (11,
20, 21, 24, 25). The means for Holsteins and Guernseys are the least
squares means of 160 Holsteins and 98 Guernseys in the crossbreeding
project at the University of Illinois, some of which are included in (29) .
The mean weights for Holsteins and Guernseys at 24, 30, 36, and 48
months of age have been adjusted for stage of lactation and gestation.
The last two lines of Table 15 indicate that the weights of the N'Dama
compare most favorably with those of the Guernsey and Holstein at 3
months and least favorably at 12, 18, and 24 months. At 3 months the
N'Dama is suckling its dam and thriving, while by 12, 18, and 24 months
it has endured the effects of weaning and the ravages of one or two dry
periods. The Guernseys and Holsteins in the University of Illinois herd
are allowed to suckle their dams for one day, after which they are put
on feed which includes a given amount of milk up to the time the calves
are approximately 3 months of age.

At one year of age both the Guernsey and Holstein are heavier than
the N'Dama is at 4 years. The weights of Hereford, Angus, and Short-
horns under similar feeding regimes would be close to that of the Hol-
stein. The question arises: to what extent is the difference between the
Musaia N'Dama weights and the University of Illinois Holstein and
Guernsey weights genetic? To improve the production of beef, it is
presently of great economic value to Sierra Leone to find out how the
N'Dama compares under Musaia conditions to breeds such as the Here-
ford, Santa Gertrudis, Brown Swiss, and Boran, or to crosses of the
N'Dama with these breeds. Further, it is potentially of greater economic
importance to determine how the N'Dama compares with other breeds
or crosses to other breeds under more optimum nutritional, management,
and health conditions. According to a report (1) on the herd at the
Firestone plantation in Liberia, crosses of Brown Swiss to the native
cattle thrive in West Africa when fed and managed well. A report (2)
on crosses of Holsteins and Zebu in Nigeria shows similar results. It
may be economically unsound to spend years trying to genetically im-
prove the N'Dama to levels now existing in other breeds. With frozen
semen and artificial insemination, germ plasm from a large variety of

1967] N'DAMA CATTLE IN SIERRA LEONE 31

breeds and strains could be used to produce crossbred cattle that might
be readily adapted to the conditions existing in Sierra Leone.

There may be some calving difficulty resulting from mating the small
N'Dama cow to bulls of larger breeds, but the frequency of such diffi-
culty is not necessarily high. Some of the Zebu cattle have been mated
to Holsteins (2) and Brown Swiss with an apparent low incidence of
calving difficulty. Further, breeds of dogs differing far more in rela-
tive size than the known cattle breeds have been crossed with only a low
incidence of difficulty at parturition. It is likely that the frequency of
calving difficulty will differ from one breed of bull to another or from
bull to bull of the same breed, and there is no accurate way to predict
which sire or breed of sire may cause a high frequency of difficult
calving without making crosses. Resistance to trypanosomes appears to
exist in the crossbreds (28).

Slaughter data

Shown in Table 16 are the mean weights for various body parts of
54 N'Dama cattle. The 54 animals consisted of 51 males and 3 females.
The ages at slaughter ranged from 32 to 49 months, with an average age
of 39.1 months. The live weights ranged from 381 to 624 pounds, with
a mean of 512.1 pounds. Both of the extreme animals were 40 months
of age. In the third line of Table 16 are the percentages of live weight
accounted for by the various parts. The sum of the percentages is 100,

Table 16. — The Average Weights in Pounds of Body Parts of 54 N'Dama

and 124 University of Illinois Holstein, Holstein X Angus,

Charolaise X Angus, and Angus Cattle

N

U

Car-
cass

Head Neck

Heart,
liver,
and
kidneys

Feet
and Offal
tail

Skin

Live
weight

Mean weights of parts
(N'Dama) 54

171.4"
34.5
33.5
153. 4b
16.6

213
28
41
548
59

.1
0
6
,2

4

31
3
6
26

2

.1 13.2
,3 2.6
1 2.6
.4
9 ....

10

2,
2,
14.
1.

.4
1
0
5°
6

13.8 29.0
1.7 6.1
2.7 5.7
15.0 98. ld
1.6 10.6

30

3.

5.

67.

7.

.1
6
8
4
3

512.1
51.2

923.0

Standard deviations
(N'Dama)

Percent of live weight
(N'Dama)

Mean weights of parts
(U. of I. cattle) 124
Percent of live weights
(U. of I. cattle)

unaccount

• U for the N'Dama = Live weight — sum of all other parts, so U = 512.1 — 340.7 = 171.4.

b U = 153.4 pounds included 80.5 pounds for content of G. I. tract, 32.8 pounds blood and 40.1 pounds

:ounted for.

counted tor.

c 14.5 pounds is the weight of the heart and liver only. The kidneys are included with the carcass.
d98.1 pounds includes 40.2 pounds empty G. I. tract, 36.4 pounds mesenteric fat and 21.5 pounds for
thymus, spleen, heart fat, lungs, etc.

32 BULLETIN No. 724 [April,

since the sum of the means for the various parts is equal to the mean
live weight. It is interesting to note that the carcass accounts for only
41.6 percent of the live weight. Dairy steers in the United States have a
dressing percentage around 55 to 57 percent, while beef steers dress 60
to 63 percent. The carcass data for the N'Dama were obtained from
animals put in a warri at approximately 6:00 p.m. and slaughtered the
following morning at approximately 8:00. The animals were therefore
without feed and water for approximately 14 hours. The dressing per-
centage for animals slaughtered under local conditions would be sub-
ject to many factors as the animals may have been walked for great
distances, dehydrated, and hungry before slaughter. O Korie et al. (24)
reported a dressing percentage of 52.6 to 54.1 percent for N'Dama
grown on improved pastures.

Also shown in Table 16 are data on 124 steers from an experiment
conducted at the University of Illinois (3) on the influence of type on
beef carcass components. The steers consisted of equal numbers of
Holstein, Holstein X Angus, Charolaise X Angus, and Angus cattle.
Approximately one- fourth of each breed group was slaughtered at each
of the weights 675, 850, 1,025 and 1,200 pounds. The average weight
when taken off feed was 923 pounds, and the average age at slaughter
was approximately 12 months. In comparing the N'Dama data with the
Illinois data, the difference in the fraction of live weight accounted for
by the carcass is amazing. The carcass as defined at the University of
Illinois includes part of the neck and the kidneys. If for the N'Dama
data one adds the weight of the neck and one-third of the weight of the
heart, liver, and kidneys to the carcass weight, this accounts for 44.9
percent of the live weight. For the Illinois data the carcass accounts
for 59.4 percent of the live weight. There is a vast difference between
slaughtering a 923 pound animal at 12 months of age and obtaining a
carcass accounting for approximately 60 percent of the live weight, and
slaughtering one of 512 pounds at 39 months of age and obtaining a
carcass accounting for 45 percent of the live weight.

It would be of interest to know to what extent these differences are
genetic and to what extent they reflect other factors. Letroteur (17)
has reported carcass data for one N'Dama and one Peul female. It is
known that, in general, the smaller the animal the larger the proportion
of total weight that is made up of viscera, internal organs, weight of
skin, and so forth. Further, the dressing percentage is affected to a
small extent by the prior feeding history of the cattle; grass fed animals
tend to have a much greater "fill" and less abdominal fat than cattle fed
a more concentrated ration. In spite of the vast differences in feeding
and management, it is probable that a good part of the difference in

1967] N'DAMA CATTLE IN SIERRA LEONE 33

dressing percentage is of genetic origin. The results of O Korie et al.
(24) suggest this.

In connection with dressing percentage it should be pointed out that
in Sierra Leone a much greater proportion of a beef animal, sheep, or
pig is sold and eaten than in Western Europe or the United States. In
general the head, skin, entire G.I. tract, lungs, feet, and spleen are sold
at one-half the price per pound for that demanded for the remainder of
the carcass (26). This will probably continue to be the practice for
many years among both the less affluent and more affluent segments of
the native population. Thus a low dressing percentage is not the serious
economic loss in Sierra Leone that it is in Western Europe and
the United States.

Shown in Table 17 are the simple correlations between the various
parts of live weight. In this case the parts of live weight are the weights
of the carcass, head, neck, heart, liver and kidneys, feet and tail, offal,
skin, and the unaccounted for fraction, U. Those correlations between
live weight and parts are generally higher than those between the var-
ious parts because of the part-whole relationship between a part and live
weight. In general the highest correlations between the various parts
are those involving the carcass while the lowest are those involving U,

Table 17. — The Standard Partial Regressions of the Body Parts on the Live Weight
of the Animal, the Correlations Between the Parts, and the Parts and Live Weight*

Ub Car-
cass

Heart, p .
Head Neck llve,r' and

and tail

kidneys 'ai1

Offal

Skin

Live
weight

Standard partial
regressions
of live weight .676 .546
on the parts

.064 .051 .051 .033

.118

.070

Simple
correlations Ub — . 044
Carcass
Head
Neck
Heart, liver,
and kidneys
Feet and tail
Offal
Skin

.049 -.040 .222 .120
.235 .357 .600 .581
.427 .300 .176
.369 .127

.330

.018
.419
.336
.388

.562
.247

.427
.427
.760
.308

.354
.382
.224

.678
.673
.358
.333

.659
.519

.447
.516

• These correlations and regressions are based on the data resulting from slaughtering 54 N'Dama animals
(51 males and 3 females).

b U = Weight unaccounted for = live weight — sum of all other parts. Correlations larger than .273
and .354 are significant at the .05 and .01 levels of probability, respectively. The average age at slaughter was
39.1 ± 39 months. The standard deviation of age at slaughter was 2.8 months.

34 BULLETIN No. 724 [April,

the unaccounted for weight. This would be expected as the carcass is
the largest of the parts actually weighed, and U includes errors which
force the sum of the other parts and U to equal the live weight. The
highest correlation between parts is that of 0.76 between the weight of
the head and the weight of the skin. No obvious cause of this high
correlation is readily apparent. The second highest is that between the
combined weight of the heart, liver, and kidneys and the weight of the
carcass.

Selection for heavier animals at a given age

Just what size cow would be most profitable in Sierra Leone is not
known; however, it seems that effort should be exerted to obtain cattle
that produce more meat at a given age. For the N'Dama to produce
more meat at a given age, it is necessary to select for heavier weights at
a given age, say 12 or 18 months, and for heavier carcass weight.

To effectively carry out such a program all female replacements
could be chosen on a basis of their adjusted weight at the chosen age.
If selection were on a basis of adjusted weight at one year of age, which
of the following two females should be culled? Female A was born in
August of 1959 and weighed 240 pounds at one year. Female B was
born in March of 1960 and weighed 220 pounds at one year. By ex-
amining the constants for month and year of birth in Tables 10 and 11
the reader can find the adjusted weights to be:

adjusted weight for A = 240 - (18.0) - (1.3) = 220.7
adjusted weight for B = 220 + (20.4) + (36.9) = 277.3

On the basis of weight at one year, Cow B appears to be the superior of
the two cows. As a practical procedure, the adjusted yearling weight
of all cows available for reproduction could be computed once a year
by using appropriate constants for year and month of birth. The cows
could then be ranked from lightest to heaviest on a basis of adjusted
weight. After considering all other debilitating attributes, one should
be able to cull 15 to 20 percent of the remaining females of breeding age
on a basis of adjusted yearling weight and still maintain a constant herd
size. If it is desired to increase herd size, less than 15 to 20 percent
could be culled; if herd size is to be reduced, a higher fraction could be
culled. As can readily be seen, there is little opportunity to genetically
change cattle by restricting selection to females only.

Most of the genetic progress from breeding cattle must come from
a wise choice and judicious use of sires. When natural service is used,
one can successfully maintain a constant herd size by using only the top
5 percent of the males, and their paternal half sibs could be adjusted

1967] N'DAMA CATTLE IN SIERRA LEONE 35

for year and month of birth and sex. Selection then could be on a basis
of the male's own weight and the average of the sire family of which
he is a part. A suitable index is:

= P + h2 [-J-EY] (p - p)

1"*"] r _ - _ i

i -t J L I + (N - i)t_

where :

Gm = expected breeding value for yearling weight of the male being

considered.

P = the mean yearling weight for the herd.
h2 = heritability of adjusted yearling weight.
r = the relationship between paternal half sibs, usually .25.
t = phenotypic correlation between paternal half sibs and is

<£/ W+<£); (see Table 14).

P = adjusted yearling weight of the male calf concerned.
N = number of paternal half sibs, including the male calf concerned,

in the family to which the male calf belongs.

Y = the average of the adjusted yearling weights of the paternal
half sibs of the male calf concerned. The male calf's own
adjusted weight (P) is included in the average.

The practical procedure for using such an index would be to com-
pute the adjusted yearling weights for all animals, males and females.
The constants for year of birth, month of birth, and sex of calf in
Tables 10 and 11 could be used for adjusting the data. The next step
would be to compute Y, the average of each sire family, and record
Y and N along with the P for each male. It would seem wise to choose
the top 10 percent of the male calves on a basis of the index and then
at a later date get rid of half of these on a basis of the slaughter data
on their paternal half sibs; it seems desirable to increase the fraction
of live weight accounted for by the carcass (see Table 16).

The adjustment for year of birth could be avoided by using a new
battery of sires each year. Progress from selection is faster if herd
sires are turned over rapidly, and the Musaia herd is large enough to
use new sires each year. In this way all sires used in a given year
would be born in the same year. Such a system would also be com-
patible with the index suggested for choosing sires. The Musaia station
could easily use 8 to 10 new sires per year, as little is gained by making
N in the above index larger than 25.

36 BULLETIN No. 724 [April,

Discussion

Tables 14, 15, and 16 show an amazingly small size, low dressing
percentage, and low expected genetic gain per generation for the
N'Dama breed. These tables raise a number of questions about cattle
production in Sierra Leone. If cattle production is to continue under
conditions where the cattle must depend solely on grazing on unim-
proved pastures of tropical grasses, with no supplemental feeding of
stored feed during the dry period, and under a nomadic system of man-
agement, then perhaps the N'Dama is as well suited as any breed for
such a system of cattle production; however, this has not been proved.
On the other hand, if cattle are to provide a major part of the food for
the people of Sierra Leone, experiments to seek answers to the fol-
lowing questions should be begun in the immediate future.

1. What is the ecological distribution of trypanosomiasis in Sierra
Leone ? How can trypanosomiasis be controlled ?

2. How do other breeds of cattle and crosses of the N'Dama with
other breeds compare with the N'Dama at Musaia as producers
of meat and milk?

3. What crops can be grown, harvested, and stored to provide palat-
able dry or succulent roughage of high nutritive content?

4. What crops can be grown to supply low-cost concentrate feed?
How will the cost of this home-grown concentrate compare with
the cost of imported oil cakes ?

5. Can a sound and dependable cattle slaughtering and marketing
system be developed ?

6. What steps can be taken to speed up the further development of
the cattle settlement scheme ?

The first question is concerned with the disease, trypanosomiasis.
One of the main assets claimed for the N'Dama breed is its reported
tolerance to trypanosomiasis (28). The nature of this tolerance is not
well documented. The tolerance appears to be present in crossbreds of
N'Dama to European breeds (28). A comprehensive and thorough
study of the incidence and the ecological distribution of the disease in
Sierra Leone is of paramount importance. Further there is a great need
for work on the prevention and treatment of trypanosomiasis. A recent
and comprehensive review by Williamson (30, 31) indicates that chemo-
therapy of trypanosomiasis may not be as futile as it once was.

In the fall of 1965, when feed was scarce, many N'Dama at Musaia
appeared to be showing symptoms of disease infections. Treatment of
the afflicted cattle with drugs customarily used to control the known
and possible infections were of no avail. The veterinarian at Teko

1967] N'DAMA CATTLE IN SIERRA LEONE 37

diagnosed the presence of trypanosomiasis in some affected animals.
Treatment specific for this infection cleared up the problem. Mean-
while three N'Dama that were sold during this period by the station
to cattle owners outside the station died of trypanosomiasis. Thus the
N'Dama cattle do become infected (they are tolerant but not resistant),
but it is only under extremely adverse conditions that the N'Dama
cattle exhibit symptoms of this infection. Further, this indicates that
chemotherapy can be successful.

The N'Dama cattle at the Musaia station are vaccinated routinely
for anthrax, blackquarter, hemorrhagic-septicemia, and rinderpest.
They are treated routinely for worms and ticks. Also they are weighed
once a month and kept in fairly open pasture. It has been reported (18)
that trypanosomiasis can be partially controlled by keeping the cattle
in large open pastures from which all bush has been removed, and by
vaccination at regular intervals during the rainy season, or both. If
other beef breeds were crossed with the N'Dama, it would seem that
little additional cost and labor would be involved to vaccinate for try-
panosomiasis once a month during the rainy season if necessary. When
one considers the size of the N'Dama as compared to the Brown Swiss,
Hereford, Holstein, Shorthorn, Sanata Gertrudis, or Boran the medical
costs per pound of beef produced would probably be less for crosses of
these breeds with the N'Dama even though they might have to be
treated periodically for trypanosomiasis.

Question two concerns the qualifications of the N'Dama breed as a
producer of meat and milk. By examining Tables 3, 14, 15, and 16 it
can be seen that the performance of the N'Dama is poor as a producer
of milk and meat. On the other hand it is not known to what extent
the differences between the N'Dama and other breeds as shown in
Tables 3, 14, 15, and 16 are genetic. Further, Table 14 indicates that
in its present genetic and environmental state, genetically increasing
the weight of the N'Dama at a given age by selection is an extremely
slow and tedious process. Montsma (20, 21) has shown that when the
N'Dama is given supplemental feeding it produces barely enough milk
to raise a calf. That the N'Dama is a poor milker is further substan-
tiated by Gaudefroy (9) and Jones (12). If crosses of the N'Dama to
breeds such as the Brown Swiss, Hereford, Santa Gertrudis, or Boran
can be protected from disease and given supplemental feeding in their
younger ages, an experiment should be begun to determine how well
crosses of these breeds with N'Dama would perform at Musaia. At
present there are no data to support an argument that the N'Dama
breed is the only breed that should be grown at Musaia. In fact the
work of Anliker (1) and Armour et al. (2) suggests that crosses with

38 BULLETIN No. 724 [April,

other breeds show much promise. There are no data on the relative
performances of the N'Dama, other breeds, and crosses of N'Dama and
other breeds under Musaia conditions. If crosses of N'Dama and other
breeds are superior to or only equal to the N'Dama under Musaia con-
ditions, it is unwise to limit the gene pool and selection program to the
N'Dama.

It is not good economic or husbandry management to take 3 years
to grow an animal to acceptable market weight when it can be done in
one-half to two-thirds of the time with supplemental feeding in the dry
period. There is an economic loss in extra labor, feed for maintenance,
medical costs, and death losses concomitant with the longer period re-
quired for reaching the market weight. Husbandry-wise, it is biolog-
ically more efficient to keep animals growing at a steady rate from
birth to market weight. If Sierra Leone is to have an economically
healthy cattle industry, it must grow crops to produce feed to supple-
ment the pastures.

Suppose that a cattle owner establishes good husbandry practices
and is able to produce good quality beef economically; what will he do
with it? There must be a sound and dependable cattle marketing and
slaughtering system established or all of the improved husbandry prac-
tices will have been for naught. If a sound slaughtering and marketing
system is developed, it will serve as an impetus to the establishment of
good husbandry practices. It may even lead to the establishment of
cattle feeders who buy young cattle and feed them for slaughter.

It is almost mandatory that Sierra Leone cattle farmers be per-
manently settled in order to have them preserve and store feed for use
in the dry season, establish and maintain improved pastures, and fully
utilize good husbandry practices. The Fula cattle owners are probably
much like other cattlemen the world over; once they see that a hus-
bandry practice yields economic results they will try to adopt such a
practice. If the cattle settlement scheme becomes widely accepted, the
Musaia station could be more effective in its function of demonstrating
good husbandry and management practices to the cattle owners. Activ-
ities such as the present field days held at the station could become a
more vital part of the station's activities and thus be more helpful in
distributing knowledge of animal husbandry practices to cattle owners.

It is believed that there are no short-cut, crash programs that will
establish an efficient and productive cattle industry in Sierra Leone.
Such an industry must develop simultaneously with and be compatible
with and supplementary to other agricultural and nonagricultural in-
dustries. To achieve an efficient and economic cattle industry the cattle

1967] N'DAMA CATTLE IN SIERRA LEONE 39

producers of Sierra Leone must have access to and make use of modern
technology. This will require much vocational teaching and education,
both in the schools and for adults. Extensive vocational and technical
education programs should be established with the idea of not expecting
measurable results until after approximately 20 or 25 years. It will take
much time to develop vocational and technical skills in the population
to the extent that an efficient and economical cattle industry can exist.
With its relatively large areas of range, its adequate rainfall, its num-
bers of cattle, and its need for meat, a cattle industry should be a sub-
stantial part of the agricultural industry of Sierra Leone.

References

1. ANLJKER, W. L. 1964. The cattle breeding program of the Firestone Planta-

tions Company. Report No. 75 of the Firestone Plantations Company Re-
search Division Botanical Department. Monrovia, Liberia.

2. ARMOUR, J., LEE, R. P., AND Ross, J. G. 1961. Observations on a cross breed-

ing experiment with cattle in Nigeria. Trop. Agr. (Trin.) 38:319-323.

3. BREIDENSTEIN, B. C. 1965. An experiment conducted at the University of Illi-

nois on the influence of type on beef carcass components. (Unpublished
data.)

4. CASH, J. G., FRYMAN, L. R., HARPESTAD, G. W., AND JOHNSON, R. V. 1965.

Summary of Illinois Dairy Herd Improvement Association for 1964-65
testing year. University of Illinois, Cooperative Extension Service, Depart-
ment of Dairy Science, Urbana.

5. DICKINSON, F. N., AND TOUCHBERRY, R. W. 1961. Livability of purebred vs.

crossbred dairy cattle. J. Dairy Sci. 44 :879-887.

6. DOUTRESSOULE, G. 1947. L'elevage en Af rique-Occidentale Francaise. Paris :

Editions Larose.

7. FAULKNER, D. E., AND BROWN, J. D. 1953. The improvement of cattle in

British colonial territories in Africa. Publication No. 3 of the Colonial
Advisory Council of Agriculture Animal Health and Forestry. Reprinted
1954. Her Majesty's Stationery Office.

8. FOSTER, W. H. 1960. The breeding of white Fulani cattle at Shika, Nigera.

SAMARU Research Bulletin No. 2. Regional Research Station, Ministry
of Agriculture, SAMARU, Zaria, Northern Nigeria.

9. GAUDEFROY-DEMOMBYNES, P. 1961. Lactation of N'Dama cows at CRA

Bambey. Agron. Trop. (Paris) 16:417-432.

10. HILL, D. H. 1964. Animal breeding and improvement in Nigeria. Outlook Agr.

4:80-85.

11. HILL, D. H., AND UPTON, M. 1964. Growth performance of ranch reared

N'Dama and Keketu cattle and their crosses in the derived Guinea savanna
zone, Western Nigeria. Trop. Agr. (Trin.) 41:121-128.

12. JONES, T. S. 1953. Report on the Musaia station submitted to the Ministry

of Agriculture of Sierra Leone.

13. JOSHI, N. R., MCLAUGHLIN, E. A., AND PHILLIPS, R. W. 1957. Types and

breeds of African cattle. FAO Agricultural Studies Publication No. 37.
Food and Agriculture Organization of the United Nations. Rome, Italy.

14. KOCH, R. M., AND CLARK, R. T. 1955. Genetic and environmental relationships

among economic characters in beef cattle. I. Correlations among paternal
and maternal half-sibs. J. Animal Sci. 14:775-785.

40 BULLETIN No. 724

15. KOCH, R. M.( AND CLARK, R. T. 1955. Genetic and environmental relation-

ships among economic characters in beef cattle. II. Correlations between
offspring and dam and offspring and sire. J. Animal Sci. 14:786-791.

16. LEGAULT, C. R., AND TOUCHBERRY, R. W. 1962. Heritability of birth weight

and its relationship with production in dairy cattle. J. Dairy Sci. 45:1226-
1233.

17. LETROTEUR, R. 1957. Rendements compare's en muscles consommobles, os,

graisse, apone'vroses. Rev. Elev. Mid. Ve't. Pays Trop. 10:41-44.

18. LEVINE, N. D. 1961. Protozoan parasites of domestic animals and of man.

412 pp. Burges Publishing Co., Minneapolis, Minnesota.

19. MASON, I. L. 1951. The classification of West African livestock. Technical

Communication No. 7, Commonwealth Bureau of Animal Breeding and
Genetics. Commonwealth Agricultural Bureau, Farnham Royal, England.

20. MONTSMA, G. 1960. Observations of milk yield and calf growth and conversion

rate on three types of cattle in Ghana. Trop. Agr. (Trin.) 37 :293-302.

21. MONTSMA, G. 1962. Observations of milk yield and calf growth and conversion

rate on three types of cattle in Ghana. II. Effects of plane of nutrition.
Trop. Agr. (Trin.) 39:123-129.

22. MURRAY, A. K. 1958. The Fula cattle owners of Northern Sierra Leone, their

cattle and methods of Management. Trop. Agr. (Trin.) 35:102-112.

23. National Academy of Sciences. National Research Council. 1965. Report by

the study group on animal diseases in Africa. Washington, D.C.

24. O KORIE, I. I., HILL, D. H., AND MC!LROY, R. J. 1965. The productivity and

nutritive value of tropical grass/legume pastures rotationally grazed by
N'Dama cattle at Ibadan, Nigeria. J. Agr. Sci. 64 :235.

25. PAGOT, J., AND DELAINE, R. 1959. E'tude biometrique de la croissance des

taurins. Reu. E'lev. P'med. Ve't. Pays Trop. 12 :405-416.

26. ROCHE, J. 1965. Oral communication.

27. Sierra Leone Department of Agriculture. 1959. Report for the year 1957.

Freetown, Govt. Printers.

28. STEWART, J. L. 1951. The West African shorthorn cattle, their value to Africa

as trypanosomiasis resistant animals. Vet. Rec. 63 :454-457.

29. TOUCHBERRY, R. W., AND BERESKIN, B. 1966. Crossbreeding dairy cattle II.

Comparisons of weights and body measurements of purebred Holstein and
Guernsey females and their reciprocal crossbreds. J. Dairy Sci. 49 :647-658.

30. WILLIAMSON, J. 1962. Chemotherapy and chemoprophylaxis of African try-

panosomiasis. Exp. Parasitol. 12 :274-322.

31. WILLIAMSON, J. 1962. Chemotherapy and chemoprophylaxis of African try-

panosomiasis. Exp. Parasitol. 12 :323-367.

ACKNOWLEDGMENTS

One doesn't become an authority on raising cattle in the
tropics in a short period of time, and I was in Africa for only five
weeks. During this period I was most fortunate to talk at length
with men who had spent long periods of time in the tropics and
to study a large volume of records and notes collected over a
period of approximately 18 years at the Musaia Animal Hus-
bandry Station. It is hoped that this report is a reasonably ac-
curate report of what was said and recorded.

The animal husbandry station at Musaia was established with
funds provided by the Colonial Development and Welfare Office
in London. Its studies were done under the auspices of the Si-
erra Leone Department of Agriculture until 1961 and subse-
quently under the Ministry of Agriculture and Natural Resources.
The records kept on the animals at the station proved to be ade-
quate for the present work and they reflect the punctuality with
which each officer, despite frequent changes of office, collected
and recorded all the data used here. I wish to thank all those
officers without whose industry and foresight this work would
not have been possible. The following officers were in charge
of the station for the periods indicated: Mr. Capstick, Agricultural
Officer, 1946-1948; Mr. J. M. Dent, Agricultural Officer, 1948-
1951; Mr. J. W. Wells, Agricultural Superintendent, 1950-1954;
Mr. A. K. Murray, Agricultural Officer, 1954-1956; Mr. B. R. Shaw,
Agricultural Officer, 1956-1957; Mr. J. M. Dent, Senior Agricul-
tural Officer, 1957-1958; Mr. C. R. Dunton, Agricultural Officer,
1958; Mr. H. E. G. Morgan, Senior Agricultural Officer, 1958-
1962; and Mr. J. Roche, Agricultural Officer, 1961 to present.
There are numerous other officers who have contributed much,
but it is not possible to mention them all here.

I am especially grateful to Mr. John Roche, the present agri-
cultural officer, whose comments and advice were most interest-
ing and constructive and of paramount importance in writing this
report. Thanks are due to Dr. Joseph Kastelic, Research Coordi-
nator, and Dr. W. N. Thompson, Chief of Party, University of
Illinois USAID at Njala University College, Sierra Leone, for get-
ting me to the records and the records to me and for help in
many ways. Finally I express appreciation for the cooperation
of the Ministry of Agriculture and Natural Resources of the gov-
ernment of Sierra Leone, Njala University, the University of Illi-
nois, and the University of Illinois USAID program in Sierra
Leone which made the study possible.

R. W. Touchberry

RECOMMENDATIONS

1. The operation of the beef herd at the Musaia Animal Hus-
bandry Station should be continued.

2. In the routine operation of the beef herd there are a number
of practices that should be continued; among these are:

a. Weighing animals routinely.

b. Giving excellent medical care and keeping complete med-
ical histories on the individual animals.

c. Keeping accurate records of weights, calving dates, par-
entage, cause of death or disposal, and date of death or
disposal.

d. Establishing improved pastures and searching for better
pasture plants.

3. Using a fraction of the herd, approximately 200 females of
breeding age, selection for weight at a given age (12 or 18
months) should be practiced within this closed herd of N'Dama
cattle.

a. All weights should be adjusted for month and year of calv-
ing before deciding which animals to cull and which to
keep.

b. Females should be culled or kept on a basis of their own
adjusted weight.

c. Males to be used as herd sires should be chosen on a basis
of their own adjusted weight and the mean adjusted
weight of their paternal half sibs (formula on page 35).

4. The other portion of the herd, approximately 200 females of
breeding age, should be used in a crossbreeding program;
frozen semen from a number of bulls of each of 3 or 4 breeds
should be used. This experiment should be carefully designed
and developed in conjunction with Recommendations 3, 5,
and 6.

5. Establish the ecological distribution of trypanosomiasis in
Sierra Leone and explore various avenues of combating or
controlling the disease.

6. Use a segment of the facilities at the station to determine
what crops can be grown, harvested, and stored to provide
economical, palatable, and nutritious roughage and concen-
trates for the dry season.

4M— 4-67— 92779

UNIVERSITY OF ILLINOIS-URBANA

Q.63D.7IL6B C008

BULLETIN. URBANA
7241967

30112019530770