Development of egg incubation and larval rearing methods for the silver barb (Puntius gonionotus) | |
| Author | Kou Boun Kheang |
| Call Number | AIT Thesis no. AE-94-27 |
| Subject(s) | Fish-culture Fishes--Spawning |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources & Development |
| Publisher | Asian Institute of Technology |
| Abstract | Induced spawning by hormone injection of silver barb (Puntius gonionotus) was done in an indoor hatchery. Egg incubation methods were done in an indoor hatchery and in pond conditions. Eggs were incubated with an airstone supplied, without an airstone supplied, with different hapa depths and different hours of exchanging hapa from the egg stocking time during the egg development. The first indoor hatchery experiment found that the egg stocking density of 2-10 eggs/cm2 gave the best result of larvae survival rate (63% to 78%). The performance of the 20 cm hapa depth achieved more than the 50 cm in the egg processing. Applying an airstone during egg development always got the best seed production results, even if using the 50 cm hapa depth and a high egg stocking density of 20 egg/cm2 (survival rate 45%). In the second experiment, the exchange of hapa at 2 hours from the time of egg stocking without an airstone supplied and an egg stocking density 20 egg/cm2 was satisfactory for seed requirements of small farmers raising fish in their rice fields or in ponds (17356 larvae ± 1123 larvae). The third experiment in an indoor hatchery and pond conditions found that exchange of hapa at 8 hours from the time of egg stocking gave higher results (two-day old larvae output was 2524 larvae ± 159 larvae) than other treatments of the same egg stocking density (20 eggs/cm2 ). But it was less than the indoor hatchery treatment which was (12714 larvae ± 203 larvae). Dissolved oxygen declined gradually from the hatching stage to the two-day old larvae stage (no airstone supplied from 6.16 mg/L to 3.5 mg/L). The fourth experiment compared early nursing fry of silver barb in ditches and hapa suspended in the earthen pond with 4 different fish stocking densities. Results should that, in the ditches, individual fish weight gain (0.293 g), daily weight gain (0.096 g/day) and specific growth rate (25.28%/day) were higher than the fry nursed in the hapa : individual weight gain (0.206 g), daily weight gain (0.071 g/day) and specific growth rate (24.95%/day). However, fish nursed in the hapa had higher survival rate (59.73%) higher than in the ditches : survival rate (26.33%). The performance of egg stocking density at 20 eggs/cm2 , without airstone supplied and with exchange of hapa during the egg development, could produce enough seed for the requirements of small scale farmers. |
| Year | 1994 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Little, David C. |
| Examination Committee(s) | Yakupitiyage, Amararatne ;Lin, Chang Kwei |
| Scholarship Donor(s) | New Zealand |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1994 |