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Objectives: This study aimed to sequence the whole genome of Vibrio campbellii RT-1 strain., Methods: V. campbellii strain was isolated from an infected shrimp, Litopenaeus vannamei collected from aquaculture ponds, India (12.1899° N, 79.9249° E). The whole genome sequencing (WGS) was performed using the Illumina Hiseq 2500 platform and assembled de novo using SPAdes and Velvet optimiser. Furthermore, the gene prediction and annotation were performed by a rapid prokaryotic genome tool-Prokka., Results: The genome of V. campbellii RT-1 strain has one circular chromosome with 6327218 bp long. V. campbellii RT-1 strain contains 5787 predicted genes with an average of 45% GC content. A total of 86 known genes associated with pathogenicity were identified and 28 genes were found to be responsible for virulence factors. Furthermore, 1112 unigenes were subjected to Gene Ontology (GO) terms, and 4895 predicted proteins were annotated with Clusters of orthologous (COGs) functional groups., Conclusions: The phylogenetic position of V. campbellii RT-1 strain was established through whole genome sequencing and genomic tools which provides a strong platform to further study on genomic alterations and phenotype of V. campbellii., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

An attempt was made to find out the impact of shrimp farm discharges on benthic diversity in the discharge point of a shrimp farm. The duration of the study was one culture period right from stocking to harvest. The results revealed that the values of environmental entities were in the safe levels. As regards nutrients, maximum value of TOC and phosphorus were recorded in the sample collected after harvest and minimum in the sample collected during culture. BIO-ENV method revealed that nitrogen, sediment salinity and TOC were manifested as best variable combination explaining faunal distribution. Polychaetes are the dominant group (50%) with 13 species followed by crustaceans (32%) with 10 species, gastropods (10%) with 2 species and bivalves (8%) with 3 species. The faunal density was found to vary in relation to months as observed in the samples which were collected during various seasons in the other areas of estuary. In line with this, diversity values were also paralleled to the faunal density. In a nut shell, the study revealed no negative impact of shrimp farming to the estuarine benthic biota.

Recent disease outbreak in shrimp farming caused mainly by bacteria, virus, fungi or a combination of these etiologic agents is attributed to disturbance in the environment of pond. To combat this, different antibiotics and chemicals are being used which are reported to be not environment friendly. Of late, a new and unique biotechnological product called "Probiotics " is being used widely by all the shrimp farmers worldwide, which is found to be more effective and environmentally safe also. In the present study 2 probiotics were used in a small 0.7 ha shrimp farm near Pattukottai in Tamil Nadu State for one culture period for the management of pond environment and also the gut ecology of Penaeus monodon. The environmental parameters analysed were within the acceptable limits. It was evident from the results that the production was better in the experimental pond where the probiotics were used. The biological parameters such as the average body weight, FCR and total harvest achieved were better in the experimental pond than the control pond, all due to congenial environment, which obtained in the former mainly due to the use of probiotics.