Effects of different feeding regimes on ovarian maturation and spawning of pond-reared giant tiger prawn in Thailand

Abstract

Large pond-reared Penaeus monodon were used in three maturation and spawning trials lasting 60 days. One group of prawns was fed a fresh diet only; a second group was supplied a fresh diet combined with a formulated pelleted diet; a third group of prawns received the formulated diet only. Total maturation (N = 66 and 55) and spawning events (N = 63 and 48) were much greater for prawns receiving only the fresh diet, and the combined fresh with formulated diets, respectively. Prawns receiving only the formulated diet matured only 12 times, and spawned 11 times. Prawns fed a fresh diet produced significantly more eggs than those given a formulated diet alone. No significant differences were seen in eggs produced per spawning event, % fertilization, % hatch or % metamorphosis from egg to protozoea. Female prawns exhibited greater mortality than did males, while females on the fresh diet only had greater mortality than did other females, presumably due to greater handling and other stress factors. Female prawns on a combined diet had lower mortality than other females. The formulated diet used is suitable for supplementation, but not as a sole maturation food.