Hatchery seed production and cage farming of Tiger grouper Epinephelus fuscoguttatus (Forsskal 1775) in Andaman and Nicobar Islands, India

1678-1685Grouper fishes have been considered as commercially important candidate species for aquaculture. Among them, the Tiger grouper (Epinepheleus fuscoguttatus) is one of the most relished finfish that demands an excellent price in the fish markets of Southeast Asia. Rajiv Gandhi Centre for Aquaculture (RGCA), has launched a project on breeding, seed production and grow out farming of grouper at Andaman & Nicobar Islands (ANI). The project developed technology for breeding and grow-out farming of Tiger grouper, which is widely distributed in Andamans and also form a candidate species for captive breeding and sea cage culture. Its wild catches are extremely limited and insufficient to meet the huge market demands. Hence, development of a standard technology for the seed production of Tiger grouper is an imperative to boost the country’s export revenue. The paper presented here, is one such initiative by RGCA on seed production and cage culture of E. fuscoguttatus

Synergetic effect of probiotic, molasses and immunostimulant supplementation on the production of white leg shrimp Litopenaeus vannamei Boone, 1931

820-828The aim of the study is to find out a suitable combination of supplements for the successful production of shrimp Litopenaeus vannamei. The experiment was performed in two different shrimp farms located in the same area at Athirampattinam (Farm-A) and (Farm-B), Tamil Nadu, East coast of India. Each group consisted of three ponds, farm-A supplemented with probiotic, immunostimulant and molasses. Subsequently, farm-B was supplemented with chemicals and probiotics. The shrimp average body weight (23.2 ± 0.41 g) survival (84 ± 0.05 %) and production (6.98 tons/ha) was significantly higher (P ) in farm-A than the farm-B. The water parameters such as temperature, pH, salinity, transparency, dissolved oxygen, total ammonia, nitrite, total plate count and Vibrio population were significantly varied between these two farms. The safe water quality parameter values were obtained in farm-A. Henceforth, the present study was concluded that the supplementation of probiotic, immunostimulant and molasses combination enhanced the shrimp production

Heterotrophic cultivation of Nannochloropsis salina for enhancing biomass and lipid production

Response surface methodology (RSM) was used to enhance the biomass and lipid content in Nannochloropsis salina due to its economic importance. Preliminary screening results revealed that the heterotrophically cultivated N. salina with various carbon and nitrogen sources yielded higher biomass (0.91 ± 0.0035 g/L) and lipid content (37.1 ± 0.49 mg/L) than that of the photoautotrophical cultivation (0.21 ± 0.009 g/L and 22.16 ± 0.27 mg/L). Significant sources that greatly influenced on biomass and lipid content of the alga were optimized through RSM. The medium consisting of glucose (7.959 g/L), sodium acetate (1.46 g/L), peptone (7.6 g/L) and sodium thiosulphate (1.05 g/L) was found to be the optimal concentration for heterotrophic cultivation by response optimizer. Confirmation experiment results for the RSM optimized concentration yielded the biomass of 1.85 g/L and total lipid content of 48.6 mg/L. In this study, we provide with a strategy for enhancing the biomass and lipid content in N. salina

A first report of symbiotic polychaete Scale Worm <i>Gastrolepidia clavier</i> Schmarda, 1861 (Phyllodocida: Polynoidae) from Lakshadweep Archipelago, India.

Symbiotic polychaete Gastrolepidia clavigera Schmarda (Phyllodocida: Polynoidae) has been documented based on the specimen collected from the intertidal area of Agatti island, Lakshadweep, India. G. clavigera is found to be associated with the variety of holothurians such as Stichopus chloronotus, Holothuria atra and Holothuria sp. The percentage occurrence of G. clavigera individuals on the symbiotic host Holothuria sp. was 41.9% followed H. atra 38.7% and Stichopus chloronotus 19.3% respectively. The present contribution also provides morphological diagnoses of the collected specimen as well as range extension of the species

Studies on the genomic DNA integrity of marine fishes through chip-based gel electrophoresis

1695-1698Present study consists the extraction of gDNA from marine fish gut samples that belong to the Chaetodontidae family. Eppendorf BioSpectrometer kinetic, based on UV spectroscopy, and Qubit 2.0, was employed for this purpose, with ladder. Thus on-chip, gel electrophoresis was performed for the analysis of gDNA quantification and sizing in the NGS sample preparation workflow. Quantification of 2 different gDNAs from gut samples of Pakistan butterfly (Chaetodon collare) and Indian vagabond (Chaetodon decussates) was made with a standard DNA

Vibrio parahaemolyticus a causative bacterium for tail rot disease in ornamental fish, Amphiprion sebae

The present study was performed to identify the tail rot disease causing bacterium in marine ornamental fish, Amphiprion sebae. Bacteria were isolated from the infected immune organs and tail region of A. sebae. Five different bacterial isolates (S1-S5) with different shape, size and colour were chosen for the infection study. The isolated strains were individually challenged with A. sebae at a constant dose of 1 × 107 CFU/fish. The virulent strain was found to be S-3, which showed maximum reproducing ability in A. sebae by causing typical tail rot disease and mortality. Furthermore, S-3 strain was identified as Vibrio parahaemolyticus by 16S rRNA gene sequencing (KF738005), biochemical analysis and amplification of tox R gene. Subsequently, extracellular products (ECPs) of V. parahaemolyticus were prepared by cellophane overlay method. The LD50 value of V. parahaemolyticus and its ECPS were found to be 1 × 105 CFU and 5 μg/fish. The histology results revealed that V. parahaemolyticus and its ECPS are the major cause of tail rot disease in A. sebae