02589nas|a2200253 i 450000500170000000800410001703500150005810000340007324500960010726000520020330000140025549000270026950001520029650200570044852014350050565000140194065000170195470000330197170000390200470000390204371001290208281000590221185600650227020260817163252.0290500s1999    th  uzm rtt  00|  a1eng d  a.b117902461 aYadav, Choudhary Nagendra Roy10aArtificial and semi-artificial propagation of Asian catfish,Heteropneustes fossilis (Bloch)  aBangkok :bAsian Institute of Technology,c1999  a68 leaves1 aThesis ;vno. AS-99-13  aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development  aThesis (M.Sc.) - Asian Institute of Technology, 1999  aAsian catfish, Singhi, Heteropneustes fossilis (Bloch) was spawned using artificial and semi-artificial breeding methods. Atiificial method involved hormonal inducement, stripping of eggs from females and fertilizing them with milt from sacrificed males. Semi-artificial method involved hormonal inducement only. Carp pituitary extract (CPE), HCG and GnRHa · implants were used in a single dose. Hormonal inducement was given only to females . Two trials resulted in no spawns. Hatching did not take place due to immature eggs. The artificial and semi-artificial propagation was successful in hatchery conditions for the first time in Nepal. Semi-artificial breeding method resulted in the highest number of fry (mean 250.53) (P<0.01). CPE resulted in the highest number of fry (mean 671) (P<0.01) in semi-artificial breeding method among all the three hormone treatments. This was followed by GnRHa implant producing fry with the mean value 419. These fish seem to be seasonal breeders. The latency period was 14 hours at 27-29°C in CPE and HCG treated females, and 21 hours in GnRHa treated females. The incubation period was 26 hours (27-29°C) in eggs from CPE and HCG treated females, and 20-24 hours in those from GnRHa treated females. Semi-artificial inducement using CPE or GnRHa is expected to be successful in hatchery propagation and commercial production of seed for individual fish farmers in the Nepalese context.10aCatfishes10aFish-culture1 aBart, Amrit N.,eChairperson1 aLin, C. K.,eExamination committee1 aMair, G.C.,eExamination Committee2 aHer Majesty Queen Sirikit Environmental Scholarships Program 1995-99 (Provided by Royal Thai Government),eScholarship donor2 aAsian Institute of Technology.tThesis ;vno. AS-99-13  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B12655