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Not AvailableIndian white shrimp, Penaeus indicus, has been identified as a national priority species for domestication and genetic improvement. Although breeding and farming of this species has been studied before the inception of commercial shrimp farming in India, reproductive and hatchery performance of this species on a mass scale has not been addressed so far. To evaluate the reproductive performance of wild P. indicus brooders, a total of 2164 brooders from the broodstock fishery along the Indian east coast were used. The experiment was carried out in two phases; in trial 1, brooders from Odisha, Kanyakumari, as well as Chennai, were used, whereas, in trial 2 brooders from Chennai coast alone was used. Only 16-32% of eyestalk ablated animals spawned successfully, whereas remaining stock was found to be nonresponsive to eyestalk ablation. Ablated females had a latency period of 7-10 days with 2-3 times spawning per brooder. The average fecundity of wild spawner was 220000±56000. Eggs per gram body weight for wild and ablated spawners were 8126±3502 and 1481±863, respectively. The egg hatchability was 80% for wild spawners whereas ablated spawners recorded 50-70% hatchability. During larval rearing cycle a lack of synchronized moulting was noticed during protozoea to mysis conversion (91.5% protozoea and 8.5% mysis 1), and mysis 3 to postlarvae (PL) conversion (30-50% of mysis 3 in PL1/PL2 stage). The study provides a deeper understanding of the reproductive performance of wild broodstock of native P. indicus, which can be used as a reference database for future breeding programs.Not Availabl

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Not AvailableKuruma shrimp Penaeus (Marsupenaeus) japonicus is a high-value penaeid shrimp in Japanese live fish markets owing to its characteristic colour and flavour. Although this species was believed to be the single species of subgenus Marsupenaeus, the exist-ence of two morphotypes (Form I and Form II) have been confirmed recently. Recent studies classified the native stock from Indian coast as Form II. Four different experi-ments were carried out to study the reproductive performance, larval survival, salinity tolerance and growout performance of P. japonicus Form II. The reproductive per-formance experiment was conducted using two treatment groups comprising female shrimp differentiated by the maturity stages (T1–Early maturing and T2–Immature). Female shrimp were unilaterally eyestalk ablated to accelerate the reproductive maturation. Although no significant differences (p > 0.05) were found in fecundity, spawning frequency, number of nauplii and hatching percentage between the treat-ments, early maturing shrimp had significantly lower (p 0.05) mean body weight (BW) and survival (1.31–1.39 g, 63.3%) compared to shrimp reared at 25 g/L (1.46 g, 79.9%) at the end of 60 days. The 167 days farming trial at stocking density of 50 PL/m2 resulted in productivity of 0.55 kg/m2, with a mean BW of 20.48 ± 0.68 g and 55% survival. Low salinity produc-tion performance observed in this study indicates that the native P. japonicus Form II may be physiologically distinct from the other forms/stock elsewhere. The study also concludes the suitability of the species for brackishwater aquacultureNot Availabl