AI SearchDevelopment of seed production techniques for green catfish (Hemibagrus filamentus)
Sython Phetdaoheuang
Development of seed production techniques for green catfish (Hemibagrus filamentus) - Pathum Thani, Thailand : Asian Institute of Technology, 2007 - 79 leaves : ill. (some col.) - Thesis ; no. AQ-07-18 . - Asian Institute of Technology. Thesis ; no. AQ-07-18 .
A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Science in Aquaculture and Aquatic Resources Management, School of Environment, Resources and Development
Thesis (M.Sc.) - Asian Institute of Technology, 2007
The green catfish Hemihagrus fllamentus (formerly identified as Mystus filamentus) is a commercially important freshwater fish in Laos and Thailand but the seed production techniques are not yet well developed. This study on development of seed production techniques was conducted in the hatchery facilities of Asian Institute of Technology and Surat Thani Inland Fisheries Research and Development Center from September 2006 to February 2007. Three experiments were conducted to determine: 1) the effect of carp pituitary gland extract and buserelin acetate (an LHRH analogue) on breeding of green catfish, 2) a suitable water supply system (static, flow-through or recirculating) for fry rearing in tanks, 3) an appropriate method to reduce cannibalism in fry rearing (use of shelters and compartments in tanks). The results showed that both carp pituitary gland extract and buserelin acetate at two injections are effective to induce spawning in green catfish but buserelin acetate had higher spawning success (all broodfish spawned in all three trials) than pituitary gland extract (80-100% spawning success). Only one injection of pituitary gland hormones resulted in less spawning success. Furthermore, two injections of buserelin acetate resulted in shorter effective time for spawning (12.1-12.2 h) compared to one injection of pituitary gland or buserelin acetate (12.6-12.7 h). In the experiment on green catfish fry rearing in different water supply systems, survival rate of fry reared in recirculating system was significantly higher (9.96 ± 1.53 %) than flow-through system (7.28 ± 0.67 %) and static system (4.20 ± 0.56 %). Survival rates of green catfish fry were very low due cannibalism. Growth rate was similar in all treatments (P>0.05). The use of shelters or compartments in rearing green catfish fry in recirculating system resulted in higher survival rates (27.14±1.93% and 22.56±1.05%, respectively) than without shelter or compartment (15.08±0.74%). There was no significant difference in growth rate among treatments. This study concludes that buserelin acetate (BUS) twice injection hormone is more effective than pituitary gland to induce spawning in green catfish. Moreover, two injections (BUS) gave better results than one dose injection. The use of shelters and compartments in rearing fry in tank recirculating system can result in higher survival rates.
Catfishes
Seed technology
Development of seed production techniques for green catfish (Hemibagrus filamentus) - Pathum Thani, Thailand : Asian Institute of Technology, 2007 - 79 leaves : ill. (some col.) - Thesis ; no. AQ-07-18 . - Asian Institute of Technology. Thesis ; no. AQ-07-18 .
A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Science in Aquaculture and Aquatic Resources Management, School of Environment, Resources and Development
Thesis (M.Sc.) - Asian Institute of Technology, 2007
The green catfish Hemihagrus fllamentus (formerly identified as Mystus filamentus) is a commercially important freshwater fish in Laos and Thailand but the seed production techniques are not yet well developed. This study on development of seed production techniques was conducted in the hatchery facilities of Asian Institute of Technology and Surat Thani Inland Fisheries Research and Development Center from September 2006 to February 2007. Three experiments were conducted to determine: 1) the effect of carp pituitary gland extract and buserelin acetate (an LHRH analogue) on breeding of green catfish, 2) a suitable water supply system (static, flow-through or recirculating) for fry rearing in tanks, 3) an appropriate method to reduce cannibalism in fry rearing (use of shelters and compartments in tanks). The results showed that both carp pituitary gland extract and buserelin acetate at two injections are effective to induce spawning in green catfish but buserelin acetate had higher spawning success (all broodfish spawned in all three trials) than pituitary gland extract (80-100% spawning success). Only one injection of pituitary gland hormones resulted in less spawning success. Furthermore, two injections of buserelin acetate resulted in shorter effective time for spawning (12.1-12.2 h) compared to one injection of pituitary gland or buserelin acetate (12.6-12.7 h). In the experiment on green catfish fry rearing in different water supply systems, survival rate of fry reared in recirculating system was significantly higher (9.96 ± 1.53 %) than flow-through system (7.28 ± 0.67 %) and static system (4.20 ± 0.56 %). Survival rates of green catfish fry were very low due cannibalism. Growth rate was similar in all treatments (P>0.05). The use of shelters or compartments in rearing green catfish fry in recirculating system resulted in higher survival rates (27.14±1.93% and 22.56±1.05%, respectively) than without shelter or compartment (15.08±0.74%). There was no significant difference in growth rate among treatments. This study concludes that buserelin acetate (BUS) twice injection hormone is more effective than pituitary gland to induce spawning in green catfish. Moreover, two injections (BUS) gave better results than one dose injection. The use of shelters and compartments in rearing fry in tank recirculating system can result in higher survival rates.
Catfishes
Seed technology