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Marcia's anthias, Pseudanthias marcia Randall and Hoover, 1993, belonging to the subfamily Anthiinae (family: Serranidae) is a highly sought after marine ornamental fish mainly due to its vibrant pink shade. The present study reports the first successful captive brood stock development, spawning, and larval rearing of P. marcia. Brood stock was developed in a 5-ton recirculation aquaculture system (RAS) using 12 wild caught juveniles. After 6 months of rearing, the fish (8–9.5 cm size) started courtship behavior. Spawning occurred at 1900 to 2100 h. The eggs (mean size - 617.9 ± 14.9 μ) were transparent, pelagic, non-adhesive and with single oil globule. The eggs hatched out after an incubation period of about 14–16 h at a water temperature of 29 °C. Newly hatched larvae measured 1206.6 ± 100.02 μ in total average length and increased to 1852.9 ± 24.68 μ at 48 h post hatch (ph). Mouth opened at 48–50 h post hatch (ph) and measured 76 to 80 μ. Larval rearing trials were conducted using rotifer (L and S type), wild zooplankton, copepod nauplii, artemia nauplii and microparticulate diet. Primordial fin development started by the 10th day post-hatching (dph) (larval size ~2.9 mm) while the opercular and dorsal spines were fully formed by 15 dph (total length of the larva was 4.4 mm). Larvae metamorphosed to miniature adult shape by 32–34 dph and on 50 dph they reached the pink colored juvenile stage (42–43 mm) and at this stage, they were transferred to nursery rearing tank. Four treatments with different feed combination were tried and treatment III with wild copepod gave an average survival of 5.2 ± 1.07% and treatment IV with Parvocalanus crassirostris gave an average survival of 7.3 (±2.51) %.

An experimental study was carried out to evaluate the efficacy of three commercially available probiotics P1, P2 and P3 consisting of mainly Bacillus spp. and nitrifying bacteria against Vibrio loads in mass culture tanks of the rotifer Brachionus plicatilis. Triplicate tanks were maintained for each of the probiotic treatment as well as for control group. All the tanks were inoculated with 50 rotifers ml-1 and were fed with Nannochloropsis oculata at a density of 1 x 107 cells ml-1. Every alternate day, all the experimental tanks were treated with probiotics at a concentration of 1 x 104 cfu ml-1 and the experiment was carried out for one week. The study showed a significant increase in rotifer density (p

Growth rates of cage cultured Asian seabass Lates calcarifer (Bloch, 1790) and cobia Rachycentron canadum (Linnaeus, 1766) in relation to the water and sediment quality of marine farm at Karwar for two consecutive crops (2012-13 and 2013-14) were analysed. No significant variation was observed in the specific growth rate (SGR) of both the species between the crops. But within a crop, variations were observed in the SGR and absolute growth rate (AGR) of both the species (p

Broodstock of the John’s snapper Lutjanus johnii were raised in sea cages from wild collected juveniles of the species. Individual fishes were tagged using passive integrated transponders (PIT), cannulated and gonadal biopsies were examined periodically for assessing the maturity status. The matured fishes were shifted from cages and maintained in indoor FRP tanks. Females were given two doses of human chorionic gonadotropin (hCG) and ovaprim @ 800 - 900 IU kg-1 and 1.25ml kg-1 respectively. Males were given only hCG in a range between 400 and 600 IU kg-1. Two successful spawning were obtained with 80-85% fertilisation rate. In both the trials, embryonic development was observed to be arrested before hatching which could be attributed to nutritional deficiency of the broodfishes and high water temperature in the spawning tank.