ARTIFICIAL SPAWNING OF PANGASIUS BOCOURTI (SAUVAGE, 1880)
Abstract
The broodstocks were fed a diet containing 40% crude protein and daily feeding rate was of 1% of body weight. Spawning season lasted from February to July with the peak in April and May. The broodfish get mature at ages of 3 and 4 years old for males and females, respectively. The GSI of female was 2.61 ± 1.01%. The ripe oocytes were of 1.8-2.2 mm in diameter. The fecundity was 7,800 ± 2,700 eggs/kg female body weight. The spawning was induced by the injections of fish pituitary gland extracts or HCG. The hormonal preparation injections were applied at least 2 times. The interval duration was 12-24 hrs. Ovulation occurred 6-16 hrs after final injection. Dry method of insemination was used. The incubation period lasted 30-33 hrs at the water temperature of 28-30°C. The 2-3 day-old larvae started to feed on zooplankton. After 2 months of rearing in the earthen pond the fingerlings weighed 7.7 ± 0.37g and reached 90.2 ± 10.3 mm in length.