GORNELL UNIVERSITY LIBRARY Cornell University Library The cultivation of pla salid in Sia Cornell University The original of this book Is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924023609831 Departemant van Landbouw eon Visser ij Onderafde ling BINNENVISSERW Boon Indrambarya (Birector -General of Fisheries, Siam) <4 THE CULTIVATION OF PLA SALID IN SIAM - LS CAgie SH3SY fé 2492+ THE GULTIVATION OF PLA SALID IN SIAM by boon Indrambarya Director-General of Fishéries, Siam. q i INTRODUCTION, . Pla salid-is a fresh-water fish. The fish, when salted and dried, is one of the highly esteemed among the Siamese, Being vegetarian, absolutely noncannibalistic in Habit, pro- lific in nature ¢ and palatable in flesh, pla salid-is chosen ‘by the Siamese Department of Fisheries to try the cultivation in ponds and to set forth ideas worked out in actual practice te be an improvement. over the old methods of merely holding young fish in ponds. This Department started the work in 194k. This paper is the summary of observations and practices and will serve as an informaticn for further consideration in the promotion of food supply in South East Asia. DESCRIPTION, — The word “ple” in Siamese means fish, "Salida", believed to be derived from a Cabodian word, means leaf. The Siamese “sometimes call this fish "pla bai-mai". "Bai-mai" means leaf, Pia salid is known selentifically as Trichogaster pec- toralis (Regan), It belongs to the thread-fin family, Osphrone- midae, as. gouramy (Osphronemus goramy) and sepat siam (T,léerdi and T. trichopterus) do. It closely resembles seépat siam more than gouramy. It can be distinguished from the formers. by oblique, and black bands on the sides and @ longitudinal black stripe from the eye to the caudal peduncle, whereas T.leeri is shiny silvery-white and T.trichopterus is dark with two | spots on each side. HABITAT, Pla saiie is common in Swamps where aquatic plants are of luxuriant growth. It is found tc thrive well in. water having the range of temperatures from 28 to 36 degrees o@iits- grade. FOOD. The fish is vegetarian and subsists mainly upon aquatic plants. Tt is fond of duckweed, and roots of pak-bung : ( Ipomea Sp. ) and of water-lettuce (Stratiotes sp.). ‘The fry feed upori microscopic plants and animals, DISTRIBU? ign: | Pla salid ie a°fish of stagnant water and oceurs.. through out Central ‘Siam’ and Cambodia, The fish is unknown and not found in Peninsular Sian, Northern Siam, ‘and North-Eastern Siam (or the Korat Pinter a), ‘until recently” when ae WAS - intro= duced by the “‘Départment of ‘Fisheriss BREEDING HABITS, Pla salid matures when it is. 7’ months old, and by that. time is about 10 centimetres long. A ripe femole of this’ size. contains’ ts 700 Cees. ‘It is ‘also fcund that'a fuil-srowm sects , will have ebout 82.000 eggs. female , 2h.5 centimetres i “the’ spawning. séason begins from April to Oatober. The. fish seems to spawit in. quiet - sha liow recesses where- the water - dis about 40 centimetres . déep: and whee’ aguatic: plants grow . ‘rather. thickly. A bubblc-nost' is prepared: ‘by uke male before the female lays its. eggs. The nest looks like a foam of soap suds, floating on the surface of water, among aquatic plants, It.has been observed that nests are made and eggs are laid: mostly after the rain, This ‘leads ‘to the assumption that not only the temperature but also the condition of water, ister ated by rain-falls, helps. the spawning BEA Iay of one fish. The re. are in & Siagle nest about 3.000 oags, ach was measures about’ 2 millime ‘ures /in- diameter, It 18 spherical and buoyant. and contains an oil globule. ‘The color of newly laid eggs is yellowish and becomes darker and darker during the cours of development. The egg will hatch out between 36 to 48 hours, The yolk sac will be absorbed within 3 to 7 days. ‘GROWTH, The followfngs are records of sizes and weights of the fish, Age Size in centimetres. 15 days 1.5 1 month pene: 2 months 6.0 % months T.0 to 9.0 6 months 10.0 to 12.0 1 year 16.0 to 16.0 “1 to 13 years 20.0 to 2.5 Size in centimetres, Weight in grams, 10.0 eo 20.0 130.0 to 140.0 : 2.5 230.0 The fish is not yet found over the length of 24.5 centi- metres. EXTERNAL SEXUAL CHARCTERS, Pla salid offers itself conveniently to us in displaying the difference in its external sexual characters between male and female. These characters help us a great deal in the pond cultivation work. The dersal fin of the male is long and pointed and ex- tends to.of a little over the basé of the caudal peduncle, while that of the female is shorter and rounded, and coy not reach the pase of the caudal peduncle, MANAGEMENT OF PISH*PONDS. ee Fish-ponds’ may be- constructed in any shape, but the rec- ‘tangular shape. is. thought to be appropriate, as conveniences in taking-care of, in locking after the. fish, and in harvest+- _ing the fish have to be considéred. The size of a spawning pond is le- metres wice and’ 20 metrés long, “while that of a Stocking pond is 2 to h times as pig. The. appropriate size of @ nursery pond is 5 metres wide and 10. metres long. The depth of water should be maintained, net less than 1 metre. It should also bé born in. mind. that ‘éach fish- pond should be made with berm, and ,provided with one or more feeds boards placed about 15 centimetres beneath the water, and provided with 2. sheds, or more ‘a nécéssary, made of thatch and erected above the . feeding boeeas. Beside these, Ipomea are planted, and should occupy- not more than three-fourth the area of each pond, ‘The inlet and outlet of the pond ‘should be guarded. with finely meshed -screens, In order to indrease the rapid growth: of Ipo omea and the production of microscopic organisms as natural focd’ in ponds, dried cattle or buffalo manure is scattered along the “water ‘Line every %. weeks with the grcvortion of oO Litres’ for 100 square metres of water area, a Regarding . the amount of fish to be punt “into the ponds, the department adopts the following proportiens: 25 pairs of. spawners are for 100 square metres of water Area § for every lssquare metre of water area are 10 fishes, of. more than. 10 centimetres in length; or 20 fishes, of 5 to 10. centi- metres in length; or lO. fishes, of less than 5 centimetres in length. » — FEEDING, ' It is found, that VacaerwaR, Moina sp., and cdépepods are’ taken by the fry. These ‘minute crustacqgns. are then raised: separately and. given to. the fry when ‘they are 7 to. 30° days: old. « After this pericd, cooked rice-bran, mixed with cooked Ipomea. or duckweed, is prepared. and made in. lumps. One hump ‘is placed on each feeding board. To train the fish, “food is tt wi tt Given at specific time, once a day, about 8 o'clock in. the morning and the water is beaten with fingers at the feeding board, the fish will soon learn and come to take food. AS rice-bran costs high, and as fresh duckweed can be found. and grown easily, the former is sometimes substituted by the latter. At the Bang-Khen Fishpond Station, termites which are easily found are also fed as additional food. The fish takes these vigorously. . ‘ To prevent the pond water from fouling by the remain and waste of rice-bran the remain on the feeding board is teken out in the following morning, and the waste falling from the feeding board ty the bottcm is checked by placing a king of fresh-water. snails, locally known as hoi-kom, Vivipara. NaTURAL ENEMIES. Pla salid has many varieties of natural cnemies, Otter (Lutra_sp.), turtles, water snakes, catfishes (Clarias sp.). serpent-headed fishes (Ophicephalus sp.) and fisheating birds such as herons, cormorants, and king-fishers, are enemies of the adult. Frogs, toads, elimbing-perch (Ariabas) and other small fishes prey upon tne fry and the eggs. However, the most dreaded are watersnakes and. serpent-headed fishes, -EFROPAGAT.ION IN WOODEN TANKS, As it is ‘found that it is difficult “tC protect. pla, salid from enemies, ar to" reduce the loss cf .eggs and fry as much as possible, the propagation” ‘In wooden. tanks is resorted to, Such a tank is made of teak, 1.5 metres wide, 3 metres long, and 60 centimetres deep. Clear water is put into the tank up to the depth of ho centimetres, The tank is three-fourth covered with a thatched shed erected about 1. metre.above it. Nests. of pla saliid, with eggs and Ipomes , are transferred from the. spawning pond: ‘to the wooden tank, and are allowed to develop therein. This method of propagation gives better result than that in the spawning pond, as it is convenient to look after the eggs and fry, and water can be removed easily. The experience, gained by this procedure, leads to another test », which turns out well, The tank is used as a spawning tank. Ipomea is placed in about _ three-fourth ‘of. the tank area, ‘This is prepared during the spawning Seascns. 5 males and 10 females are put in, Within a few days, the _ fish will spawn, The nests with eggs are then transferred to another tank ,. while the spawners are’ allowed tc remain to cont Inue their spawning activity in the previous tank. The fry are fea in the tank w th water- ~fleas and cope = 6a8 in the. same manner as mentioned elsewhere. After’ one -month, they ‘are’ transferred to the nursery ponds, TRaNSPORTATION. -The transportation of pla salid is also tried. It is Pound that small pla_ salia,. 3 centimetres in length, can Z stand long journety better than large ones, The rish, after saken up from the pond, are put in wooden. tanks with clear and cool water, and-are given’ ‘one day's rest. -During this: time and the journey, no food should be given. The fish are put in round tin cans, having 20 litres capacity. Three- fourth of the can is filled w th clear and cocl water. and some Ipemea, The amount of fish put in: enek Can varies accora= ‘ing to fish sizes: fer instance, fon Pull grown size lo, for medium size 80 and for ‘small size, 5 centimetres in length, 200. During the journey, the cans should be covered with — perforated lids and placed, af’ possible, in acol or ‘damp places, The water should be frequently-aerated, with the use of a perforated dipper. . However; -Eood result is obtained by changing water every 4 hours, 2 RIELD ACTIVITIES, : The fish was introduced in the province of Chumporn. in 1938, Farmers were first advised to try the. pond cultivation following the directicns given by the department. Owing, to adverse ecnditicns of ‘the region, namely the site, the nha sufficient supply of water thrceughout the year, and the suk, Jection to flooding during the rainy season, the procedure of Sepat siam cultivation in Malaya was later adopted. It is reported that the fish thrive well in ponds, ditches, and swamps. Naw fresh pla salid is found on sale in the Chumporn market. From Chimporn, the fish finds its way down to Surat and Pataiung. - In 19ho, some pla salid were taken up north to Lampang , Chiengrai, and Chiengmai, It is reported that the fish adapt itself well to the climatic conditions. of Northern Siam. In 192, the fish was liberated in a large swamp, known | as Nong Harn in the province of Sakol Nakorn, It is now in ditches, bogs and ponds. In 19,, the department tried to raise pla salid in an acre of paddy farms at the Bangk-Khen.Fishpond Station, The farm was so prepared ‘that it could be supplied with water up fo 40 centimetres in depth and was also provided with a small pond, 2 metres wide, 5 metres long, and one metre-deep. This pond served as €& retreat for the fish when water recoded, 1,500 pla salid, having the total weight of .4.9 kLlograms , were put into the pond. and were fed with cooked rice-bran and Ipomea.for it mcnths. The fish were collected after the harvest of rice, and 873 of them weighing 18.75 kLlograms were reclaimed, It was.found that, water in the experimenting farm per- colated - fast, and could only be maintained at 17 centimetres 4n depth; Anabas and Oplicephalus' were also ‘prevalent, They were. eventually thought to be the causes of the loss of pla salid, However, the Siamese Department of Fisheries still has a strong believe that pla.salid can be raised success~ fully in paddy fields, if proper sites and sufficient | amount of water are secured, The department hopes to try the experiment again in terrace-farms in Ghiengmai, where water is. plentiful throughout the year and wheré its natural enemies are minimum, | ee eee ee ew ee ee