U.S.Committee on Merchant

Marine and Fisheries,

Statement of Dr.Hugh M,Smith,

on Stucy of Fish Diseases,

91a

STUDY OF FISH DISEASES.

[S. 8123, Sixty-first Congress, second session. ]

AN ACT To establish a biological station for the study of fish diseases.

Be it enacted by the Senate and House of Representatives of the United
States of America in Congress assembled, That out of any moneys in the Treas-
ury not otherwise appropriated there is hereby appropriated—

For the construction and equipment of a biological station, under the direc-
tion of the Bureau of Fisheries, for the study of fish diseases and experimental
work in the interests of fish culture, at some suitable site to be selected by the
Secretary of Commerce and Labor, including purchase of site and the construc-
tion of buildings and ponds, forty thousand dollars.

For all necessary expenses in connection with the special study of fish dis-
eases, in the interests of fish culture, ten thousand dollars.

“us
~ CommirreeE oN Mercuantr Marine Anp FISHERIES,
Houser or REPRESENTATIVES,
Thursday, January 26, 1911

The committee proceeded to the consideration of S. 8123 at 11.10
o’clock a. m., Hon. William S. Greene (chairman) presiding.

STATEMENT OF DR. HUGH M. SMITH, DEPUTY AND ACTING COM-
MISSIONER OF FISHERIES.

The Cuarrman. We will now hear from Dr. Smith, representing
the Commissioner of Fisheries, on Senate bill 8128.

Dr. Suirx. As the Deputy and Acting Commissioner of Fisheries
I have been authorized by Secretary Nagel to appear before this com-
mittee and state the position of the department and the Bureau of
Fisheries with reference to Senate bill 8123, and I would like to sub-
mit a very brief statement on the matter, with your permission.

A subject that is already very important in the fish-cultural work
of the Government and is yearly becoming more so is fish diseases.
The cultivation of fishes, like the cultivation of domestic animals,
predisposes to maladies of various kinds from which wild fishes are
practically free.

The Bureau of Fisheries has been obliged to spend considerable
time and money in the investigation of more or less serious epidemics
affecting young fish and brood stock at our hatcheries, and has been
called on repeatedly to render aid to the States in similar emergencies.

76597—11

2 STUDY OF FISH DISEASES.

With very limited means and facilities, we have achieved consid-
erable success in ascertaining the causes and in suggesting ways to
cure and prevent certain troublesome diseases affecting the fishes of
the fresh waters that are cultivated in ponds. We have long felt
that the situation demands more comprehensive and energetic con-
sideration, and we have been hopeful that Congress would be so im-
pressed with the importance of the matter that adequate facilities
would be provided. Congress is most liberal in establishing fish
hatcheries in all parts of the country. What is now urgently needed
to make the operation of these hatcheries more efficient and more
economical is a station established especially for the investigation of
practical and passing problems in fish breeding. There is an agri-
cultural experiment station in every State—may there not be one
fishery experiment station for the-entire country?

The most serious, widespread, and destructive fish disease now receiv-
ing attention and demanding the most careful study is malignant tu-
mor, affecting the thyroid gland of the salmons and trouts. This tumor
has all the characteristics of cancer, but in order not to unduly
alarm the fish-eating public. we prefer to call this affection the throat
or thyroid tumor rather than by the dreaded name of cancer. Facts
regarding the prevalence of this disease, its ravages in Government
and State hatcheries, and the problems that are confronting the fish-
culturalist can be presented to the committee by Dr. Gaylord better
than by me, as he has been giving special personal attention to this
subject for a year or more.

I would like to say that Dr. Gaylord represents the highest per-
fection of knowledge of the whole subject of cancer. He is the lead-
ing specialist on the subject, and we have been very fortunate in
securing his services in this great emergency that has recently come
up in our work.

In the event of the establishment of this station this fish cancer
will be the chief subject for investigation for several years at least.
We are hopeful that the disease may soon be eradicated and meas-
ures devised for preventing its recurrence.

As long as fish are cultivated, however, there will be some kinds
of maladies to combat, and the proposed experiment station will
become increasingly useful and necessary with the development and
expansion of artificial propagation.

We foresee some very important work that may be done at such
a station that can not be undertaken at the ordinary hatchery where
every effort is put forth to produce a large output in order to meet
the demands that are far in excess of the supply. I have reference to
the institution of experiments having for their object the improve-
ment of the food qualities of our fishes. What selective breeding
has done for poultry, cattle, horses, and dogs, selective breeding may
do for bass, trout, and other fishes; but this i is a subject to which as
yet no attention whatever has been given owing to lack of facilities.
One does not have to be a prophet to be able to predict that it will be
possible to produce breeds of fish that will be immune or very
resistant to disease, and will have food qualities and size superior to
the wild fish.

An aspect of this matter which I think should be brought to’ the
attention of the committee is the very large commercial value of the

A, i: en
Re S22 ’

N

! y SHIT

ra! MACs STUDY OF FISH DISEASES. 3

141

fish eggs, young fish, and brood fish that are imperiled each year by
the various epidemics and maladies to which the output of the fresh-
water hatcheries is lable. I have been making some calculations
based on the market value of our product as determined (1) by the
actual cost of manufacture, so to speak, and (2) by the quotations

-of private individuals engaged in raising fish for sale; and I have

arrived at the conclusion that the annual output of the Federal
hatcheries alone represents an actual money value of not less than
$1,000,000. This output is imperiled by our inability to handle ade-
quately the diseases that are constantly coming up.

Mr. Horson. Will you tell us appreximately what is the capital
invested in the plants that have the output of a million dollars?

Dr. Smiru. They are, I believe, 31 hatcheries, whose output is
now involved in fish epidemics.

Mr. Hoxson. Do they yield the million dollars that you estimate?

Dr. Smiru. Those hatcheries do.

Mr. Hogson. And cost approximately $25,000 ?

Dr. Smirn. Yes.

Mr. Hogsson. And then, how much to maintain, on an average,
each year?

Dr. Smiru. The average personne! of a hatchery costs $4,500.
About that much more, or, in some exceptional cases, twice as much
more, is required to operate and maintain, depending altogether
on the nature of the work.

Mr. Govuupen. The bureau has been very kind to me in furnishing
me with bass and all other fish I needed for a fresh-water pond up
in Maryland. Last spring, in April, about 150 or 200 fish, black
bass principally, came to the surface and drifted to the shore, dead.
Can you give me any explanation of what could have occurred? It
must have been some disease. They weighed anywhere from a quar-
ter of a pound up to 4 pounds. It almost depleted the fresh-water
pond.

Dr. Smiru. There are so many ways that fish can be killed in a
wholesale way that it would be impossible for me to make any sug-
gestion.

Mr. Govuipen. It was not the ice, because the ice had disappeared
two months before. But there were at least 150 to 200 of them, and
it looked to me like a very great pity.

Dr. Smiru. I would like to say that we have found that one of the
principal causes of disease in basses and trouts that are reared in
ponds is bacterial infection. The fishes, owing to the medium in
which they live, seem to be particularly lable to diseases of a bacte-
rial nature, and I will illustrate the seriousness of this matter. A
few years ago we had at one station a prospective output of a mil-
lion and a half yearling brook trout, and 1,200,000 of them died in a
very short time of an obscure bacteria! disease, which we have since
been able to study and hope to prevent recurring.

Mr. Harpy. Right along the line of what Mr. Goulden was saying,
we had a large artificial tank near my home which was stocked for
breeding purposes with hickory shad, and for about two years they
increased very enormously, until one day after a big rain, all of a
sudden when that tank ran over the dam enough to “get back to its

4 STUDY OF FISH DISEASES.

level the whole border of it was covered with dead shad, and I do not
think there has ever been a shad in it since.

Mr. Goutpen. I think one of the uses of this proposed experiment
station would be to determine, if possible, by investigation the nature
of the disease and the remedy. I did not bother the bureau with a
complaint in my own case, because I knew you had enough to do
without it, and I knew you were not equipped and in shape to take
charge of an individual experiment of that character.

Dr. Smirn. I would like to say that the Federal Fisheries Service
is looked up to by all the States having fish-cultural work, and that
means about three-fourths of them, and whenever any troublesome
fishery question arises in a State, or in connection with State fish-
cultural work, we are called upon to make a study of it; so that this
proposed laboratory would be useful to all the States, as well as to
the Federal Government.

I would like to have reproduced in the records of the committee two
brief references to this subject that appear in the last report of the
Commissioner of Fisheries.

The Cuatrman. That can be done.

Dr. Smru. I have nothing else to say.
' Mr. Srureiss. Do you not think you owe it to the public, if it is
cancer, to call it cancer?

Dr. Smrru. Until we have gotten a little further along in our work
we have not wanted to unduly alarm the people. As a matter of
fact, however, the existence of cancer in fish is now pretty well rec-
ognized by the public.

Mr. Witson. Are there not various opinions amongst the medical
profession as to whether fish do cause cancer ?

Dr. Smiru. I would like for Dr. Gaylord to speak on that point.
I think there is some doubt as to whether fish have given. cancer to
human beings or whether human beings are responsible for cancer

in fish. But, in any event, it is a very important problem that ought

to be studied.

STATEMENT OF DR. HARVEY R. GAYLORD, DIRECTOR OF THE
NEW YORK STATE CANCER LABORATORY, OF BUFFALO, N. Y.

Dr. Gaytorp. Gentlemen, perhaps you would be interested in
knowing the way in which we became interested in this subject,
which, at first glance, might appear somewhat foreign to an investi-
gation of cancer in human beings.

The past 13 years comprehends practically all that has been ac-
complished in modern cancer research, and the advance in cancer
investigation we owe almost exclusively to the study of cancer in the
lower animals. About 10 years ago the investigation of cancer,
which had become a very acute problem before the medical profes-
sion, was taken up energetically, and was, fortunately, put upon an
experimental basis by the discovery, or the recognition, of the fact
that cancer could be transmitted from one animal to another, ex-
perimentally, by grafting, by transplantation. That gave us the
means of experimenting with cancer. It also attracted our attention
to the prevalence of cancer in the lower animals. Out of those ob-
servations there came certain very suggestive facts concerning the
endemic occurrence of cancer. Our attention has also been called

ee

STUDY OF FISH DISEASES. 5

to the occurrence of cases in certain localities, and, among other
things, our attention was attracted to a curious geographical dis-
tribution of cancer, which suggested a relationship between cancer
and water.

In due course of time that naturally attracted our attention to the
question of whether fish, the inhabitants of the water, suffered from
cancer and allied diseases as did other animals. There is a marked
distinction in the distribution of cancer in animals between the wild
and the domesticated. It is true we have nothing like the accurate in-
formation regarding wild animals that we have regarding domesticated
animals. But from certain significant facts in relation to the distribu-
tion of cancer in man, it is pretty well known that civilization has
a marked effect upon the incidence of cancer in man, and that do-
mestication of animals has a like effect. So when we came to investi-
gate the question of whether fish were affected by cancer, it was a
particularly interesting question to us, because they are a species far
removed from the domestic animals. We shortly found that the fish
were affected by cancer, and that those principally affected were in
the domesticated state. Some three years ago our attention was
called to the possibility of cancer in hatcheries, and our first obser-
vations were made in the State of New York, where, in a certain
hatchery, in due course of time, an epidemic of cancer of the thyroid

land appeared, and in one summer 3,500 fish died with cancer, and
in the following summer some 3,000 fish died, and that practically
depopulated that hatchery.

We had never seen anything equaling the epidemic features of this
disease. The thyroid gland, which is a gland situated in the neck,
has a very intimate relationship with water. It is a gland which,
in some countries, is very widely affected. An enlargement of the
thyroid gland is, perhaps as you know, called goiter, goiter being an
enlargement of the thyroid gland. In Switzerland and in the moun-
tainous regions of eastern Europe goiter has arrived at a degree of
economic importance which is quite serious. In Switzerland they
refuse every year 7 per cent of the recruits for the Swiss Army
because of goiter. There are districts in Switzerland in which as high
as 70 per cent of all the young people have affections of the thyroid
gland, and it is now firmly established that goiter is a disease result-
ing from the use of water from certain sources. It has long been
known that there are goiterous wells, goiterous springs, and goiter-
ous streams. .

When this fact was properly recognized, in the eighties, a certain
district in Switzerland, known as the Aarau district, changed its
water supply, secured a water supply from a district which was free
from goiter, and in the course of about 11 years the subsidence of
goiter in that district fell from 59 per cent to less than 23 per cent.
It has recently been demonstrated that goiter can be given to animals
by taking the water from certain localities and certain wells and
giving them exclusively that water, taking other animals and giving
them water from other sources as a control. Furthermore, it has
been found that if the water is boiled it destroys the activity of the
water, and it has also been shown it can be filtered through a so-
called germ-proof filter without eliminating the agent which pro-
duces goiter.

6 STUDY OF FISH DISEASES.

Cancer of the thyroid gland, it may be stated, always begins as
goiter; that is, the greatest authority on the subject, Prof. Kocher
told me in Paris this autumn that he had never seen a case of cancer
of the thyroid that had not begun with goiter. It is an exceedingly
suggestive thing that fish, which live in the water, should have the
type of cancer which is associated with this gland, which, in itself,
is subject to the disease resulting from the use of certain water
supplies.

It is impossible to tell you to-day how widespread goiter is in this
country, but it is certainly a disease which is widespread, and it is on
the increase. We have to-day no proper statistics giving us any idea
of the geographical distribution of goiter. The reason for that is
that our Census Bureau deals with mortality statistics, and a great
many cases of goiter recover, and so those statistics give no adequate
idea. This much can be said: That goiter in this country is on the in-
crease; all surgeons are agreed to that and with the fact of its dis-
tribution through water. I think the contemplation of the fact that
fish are peculiarly susceptible to goiter and that type of goiter in
fish breaks out in great epidemics and terminates in a large number
of cases in cancer is a question of great importance so far as the
study of cancer in human beings is concerned.

Dr. Smith was asked a question with regard to the relationship of
cancer in animals to human beings; whether there was a direct con-
nection between the two. I do not think that question can be an-
swered until we have more thoroughly investigated the subject. It
is a fact that the distribution of cancer in the United States is almost
identical with the distribution of the class of fish with which we are
dealing; in other words, these fish live in the region in which cancer
is most prevalent. It is also a known fact in Switzerland that the
distribution of goiter in human beings and the distribution in animals
is practically identical.

It is just as possible that the fish have contracted the disease from
the pollution of the streams by man as it is that the fish are a factor
in the distribution of the disease. In all these districts where you
have a relationship between the animal and the human you have a
vicious cycle; one thing helps the other.

In the last decade cancer in the civilized world has increased the
world over; in the civilized countries, where the statistics are availa-
ble, not less than 20 per cent. In the State of New York, where we
have accurate statistics and have studied the matter carefully, in the
last 12 years cancer has increased 25 per cent in proportion to the
population. During the same time tuberculosis has decreased 4 per
cent. We have no cure for tuberculosis, but we do understand the
nature of the disease; we contend against it, we educate the public,
and we are putting up a general educational fight, and it is begin-
ning to show itself in figures. But in cancer the medical profession
has been divided as to its nature, and we do absolutely nothing. Pro-
posals are made that we should combat cancer on the ground that it is
an infectious disease, and that brings out criticism. Some say that
is a foolish proposition.

It is my personal belief that cancer is an infectious disease, and I
am not alone in so thinking. There is a mass of evidence pointing
in that direction. Within the last few months a crucial experiment,

STUDY OF FISH DISEASES. 7
one which all investigators have been seeking to accomplish, has been
successful in this country, and puts the corner stone in the structure.
The experiment to which I refer was made by Dr. Peyton Rouse, of
the Rockefeller Institute, who, by a fortunate combination of cir-
cumstances, has been able to separate a virus which, injected into
animals, will produce cancer, and that virus passes through a so-
called germ-proof filter. It therefore belongs to the class known as
filterable viruses. You have yellow fever, you have foot-and-mouth
disease, and pigeon pox, and a large group of so-called filterable dis-
eases. In that stage, undoubtedly, “the organism is so small it can not
be seen with an ordinary microscope.

I have referred to these facts to indicate to you the progress of
modern cancer research, so you may see the importance of this ques-
tion. The artificial propagation of fish is a beneficent and proper
function of this Government; no country in the world has done quite
as much, perhaps, as the American Government, and its Bureau of
Fisheries is a model for all the other countries, and the States of this
country are actively engaged in the same thing. But our Govern-
ment gives the Bureau of Fisheries but $30,000 for all scientific work.
I, myself, have, in Buffalo, an appropriation from the State of New
York for the investigation of cancer alone of more than $30,000.
That is not the way the Government should proceed with practical
problems of this sort. In distributing fish you may be distributing
disease, and you can not carry on such activities as the Bureau of
Fisheries is engaged in without considering the public hygiene; and
the responsibility can not be shirked. It ‘will be perfectly possible
for them to produce sound and healthy fish, and to continue their
activities in a proper way; but to do that they must have a labora-
tory for the investigation of fish diseases.

We have given a considerable part of our time and activities to this
work, and have done all we possibly could. Last year the situation
reached the point where our institution could not carry this burden,
and, as it is partly a burden of the Government, I went to the Presi-
dent with the matter, and he sent a special message to Congress. I
assure you it is a very important question, and it reaches far beyond
the question of fish culture. There are many practical problems in-
volved in this which the Bureau of Fisheries should take charge of.
If the Government will establish this laboratory, it will have the
cooperation of our institution; if it does not, we can no longer carry
the burden of special researches for the benefit of fish culture. We
are willing to do everything we can, and for two years we have given
up a Aes part of our time and endeavor to this investigation.

GovuLpen. Can you tell us the origin of this cancerous sub-
ais in the waters, and what is a pr eventive for it /

Dr. Gaytorp. I haven’t any idea.

Mr. Goutpen. You do not know how it is produced in the water;
you do not know how it gets there?

Dr. Gaytorp. Not at all.

Mr. Goutpen. Is it only in polluted streams, or is it in pure moun-
tain streams? Where do you find it?

Dr. Gaytorp. The distribution of cancer in this country is in
mountains, well-wooded and well-watered regions, and it is quite as
prevalent in the country as in the cities, and affects those engaged in
outdoor work to a greater degree than indoor occupations.

8 STUDY OF FISH DISEASES.

Mr. Goutpen. It seems to destroy the theory, then, that it is found
only in polluted streams?

Dr. Gaytorp. I will not say that. It is a very difficult matter to
say how much pollution it will take to start cancer in streams. There
has been a report of a very striking occurrence in Norway, where a
stonecutter, who was building a wall near a small stream had cancer
of the rectum and defecated on the bank of the stream. In the
following year a number of cases of cancer developed in houses
adjacent to the stream farther down.

I can tell you of another instance reported at the International
Cancer Congress by a prominent cancer investigator, Dr. Sticker,
who was previously a great opponent of the virus theory. The story
was something like this: A certain count in Wurttemberg and the
countess, his wife, died of cancer, and the rumor came from the
schloss that nearly everybody in that place died of cancer. It came
to the ears of the German Kaiser, who has cancer in his family, and,
being intensely interested, he detailed Dr. Sticker to go there and
investigate. He went to this estate and found a small pond, about
1,000 feet long by 600 feet wide. On one side was the schloss, or
villa; on the other side were the farm buildings, and around one
end of it was a little village of retainers of the count, who lived
there—the butcher, the baker, the shoemaker, and so on. In the last
10 years 20 people had died of cancer in that locality, including the
count and countess. Eight of those people died of cancer of the
stomach. He found two cases of cancer of the stomach at the time;
one of them he did an autopsy on, and the other, a person in bad
health, was found on examination to have a tumor of the pylorus.
He found them pumping the water out of this pond into the castle,
using it without filtration, and drinking it. The water from the .
stable yard, just across the pond, ran into it, and the water was quite
foul. They also told him that the carp in that pond had tumors. '
He did not see any of these, but the fishermen described them so ac-
curately that there was no doubt about it, and they were going to
seine the pond to secure material for him. I only speak of that to
show you something of the infectious nature of cancer.

There are towns in Europe where they have moats, where the con-
centration of cancer is very marked. These things are all subjects
- for accurate investigation. I think this year will mark a great
stimulation to the investigation of cancer as a parasitic disease. The
agencies engaged in the distribution of cancer, and why it is increas-
ing, are yet to be determined. But certainly we can not ignore a
factor such as this of cancer im fish.

Here is a map of New York, and you will see that one of the largest
districts of concentration of cancer is in the Adirondacks.

Mr. Gouipen. The Adirondacks should have the best and purest
water.

Dr. Gayuorp. The streams in Switzerland that produce goiter are
almost the best and clearest water, and the most pure from the usual
standpoint. Here are some pictures of fish. Here is a cancerous
whitefish living in Lake Cayuga, N. Y., 5 miles below where an
epidemic broke out in a State hatchery. There is a fish living under
conditions of wildness, you might say. Here are a large salmon and
a small fingerling showing throat tumors.

STUDY OF FISH DISEASES. 9

Mr. Harpy. In other words, you think it is possible the fish hatch-
eries may distribute this disease all over the country ?

Dr. Gaytorp. I think they ought to take every precaution to be
sure they do not. We have succeeded in curing this by adding one
to five million iodine and one to five million mercury, both of them
antiseptics, and both those agents make tumors decrease in size. It
would not be difficult to adapt our methods to fish culture. Fish
culture will have to be modeled along those lines.

Mr. Harpy. Is not that a pretty good indication that this fish dif-
ficulty is not cancer? You can not cure cancer in the human being
by a little application of iodine.

Dr. Gaytorp. No, sir; but cancer is surely curable. There were
some cases of cancer reported cured by vaccination at the Inter-
national Cancer Congress, in Paris, in October last. I will take
pleasure in showing you a picture of the first case cured in this
country by this method.

Mr. Srureiss. Have you, in any of the cases of curing, drawn any
definite conclusions?

Dr. Gaytorp. I can only state that the first so-called alleged six
cases of cure are based upon scientific research going back about 10
years, the application of methods which have cured, experimentally,
moculated animals. We are no longer searching in the dark. We
are working on a scientific structure built on years of work.

Mr. Harpy. I saw a statement recently in a newspaper of some
definite instance in which it was claimed that an absolute case of
cancer had been thoroughly cured, but I do not recall the particulars.

Dr. Gayrtorp. I will show you a photograph of that case. That
case got into the newspapers about a week ago, unfortunately.

Mr. Wiuson. That was one of your cases, was it not?

Dr. Gayrnorp. Yes. That was the case we began treatment of last
May. We have been working on vaccination since 1907.

Mr. Srurciss. What do you use—monkeys and guinea pigs?

Dr. Gaytorp. We use rats and mice. You have not heard of us
through the antivivisectionists, because the ladies are not interested
in rats and mice.

Mr. Sruretss. You are pretty adroit in that respect.

Mr. Harpy. If they serve the purpose just as well I wish you
would use only rats and mice. |

Dr. Gaytorp. The rats and mice have served an enormously im-
portant purpose.

Mr. GounpEen. You are connected with the Buffalo Cancer Labora-
tory ?

De: Gaytorp. I am director of the State cancer laboratory. That
was the first institution established for the special laboratory study
of cancer, and many other countries have followed.

Mr. Harpy. Did you tell what your treatment was?

Dr. Gaytorp. That boy was vaccinated with a vaccine made from
rat cancer.

Mr. Harpy. In other words, you cure like with like?

Dr. Gaytorp. We discovered in 1907 that you could vaccinate ani-
mals in the presence of cancer and cause their cancers to go away.

Mr. Srureiss. Similia similibus curantur ?

Dr. Gayxorp. No; in this case it is unlike curing like. Of course,
if you carry that to its final conclusion like does cure like. If you
recover from a disease the disease cures itself.

10 STUDY OF FISH DISEASES.

Mr. Harpy. Is it not, rather, on the principle that by the injection
of this weakened form of the disease the system is able to resist that
and strengthen itself?

Dr. Gaytorp. That is protective vaccination. This type of vacci-
nation consists in bringing out the latent forces at a time when they
can be available. The principal trouble with tuberculosis, and dis-
eases of that sort, is that there is always evidence of antibodies
in the blood, but they are not sufficient. If you can stimulate the
resistive powers of the individual to rise up you can overcome the
disease. You produce in the individual himself an antibody to
overcome his disease.

Mr. Harpy. Is that along the line that Mithridates was said to
have accustomed his body to poisonous substances ?

Dr. Gaytorp. Exactly. That is active immunity.

The Cuarrman. We are very much obliged to you, Doctor, for your
information.

(Thereupon, at 12 o’clock noon, the committee proceeded to other
business. )

(The following extracts from the report of the Commissioner of
Fisheries to the Secretary of Commerce and Labor for the fiscal year
ended June 30, 1910, were submitted by Dr. Smith, the deputy and
acting commissioner :)

STUDY OF FISH DISEASES,

During the fiscal year the bureau has continued cooperation with the New
York State Cancer Laboratory in the investigation of thyroid tumor or cancer
in domesticated fishes. An aquarium with two independent systems of closed-
water circulation, with proper means of refrigeration, has been established for
the observation of salmon and trout and experiments in inoculation and treat-
ment. Investigation at various stations of the bureau and at other hatcheries
have shown that the disease is even more widespread and general than was
suspected. Considerable difficulty has been encountered in obtaining for pur-
poses of experiment a sufficient number of fish above suspicion of infection,
and it has been necessary in this effort to secure a quantity of wild trout from
remote streams. Owing to the technical difficulties attending this work, which
are equal to those retarding the advance of knowledge relating to the cause
and nature of cancer in human beings, progress is made only by slow and pains-
taking steps and by the use of the most approved appliances and methods. For
this reason it is highly important that the bureau should be provided with a
well-equipped laboratory and experimental hatchery, not only for the purposes
of the present investigation, but for the study of the many other diseases affect-
ing fishes, both under domestication and in a state of nature. The President,
in a special message to Congress dated April 9, 1910, urgently recommended an
appropriation for this purpose.

During the year the bureau was called on to investigate epidemics among
hatchery fish at Spruce Creek, Pa., and Roxbury, Vt. At the former place the
mortality was due in part to the thyroid tumor or cancer before alluded to,
but the majority of the deaths were apparently caused by a bacterial infection
which the bureau has found at other places, but which it has not the facilities
to study at present. At Roxbury the disease is also infectious and annually
causes large losses. The bureau has likewise made investigations in Penn-
sylvania, Ohio, and West Virginia upon the kindred subject of the pollution of
streams in its relation to fishes and the fisheries.

LABORATORY FOR THE STUDY OF FISH DISEASES.

‘There is again urged the importance of a station for the study of fish diseases
and experiments in the interests of fish culture. In some of the batcheries
of the bureau and in similar establishments under State and private auspices
certain fish diseases have become so prevalent as to make it a matter of grave

STUDY OF FISH DISEASES. ee

consideration whether the propagation of certain species, especially the trouts,

should not be abandoned. It frequently occurs that the fish and fry are
decimated by epidemics for which there are no known remedies, in consequence
of which there are annually entailed on fish culture large wastes of time and
money. In addition to the financial loss, embarrassment arises at times in fill-
ing legitimate demands for fish for restocking depleted waters, and the effect
on the morale of the employees of the bureau who have to struggle hopelessly
against an obscure disease is not unworthy of consideration. The gravest
phase of the matter, however, is the possible relationship of some of these
diseases to more or less kindred affections occurring in human beings. It
has been determined that a type of cancerous affection is of widespread dis-
tribution among domesticated trout and their offspring planted in the streams.
Whether this disease has a causal relation to cancer in human beings, or
whether the two are to be even traced to the same source, is a matter of doubt,
but the annually increasing mortality from cancer in man and certain re-
markable coincidences in the geographical distribution of the disease in man
and fish render it imperative that it should be made the subject of minute in-
quiry. The matter therefore has not only economic but humanitarian aspects,
and the consideration of the serious character of the latter prompted the Presi-
dent to submit to Congress on April 9, 1910, a special message advocating
an appropriation of $50,000 for the construction and equipment of a laboratory
adequate to enable the bureau to discharge its plain obligations. The bureau
in the meantime is proceeding in the investigation to the limit of its powers,
but it may be stated emphatically that it can make but little progress without
the special facilities asked for.

MAKERS
SYRACUSE, - N.Y,

PAT. JAN. 21, 1908

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