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Variances and genetic parameters were estimated for birth weight (BW), 14 day body weight (14dW), 28 day body weight (28dW), 42 day body weight (42dW) and weaning weight or 56 day body weight (56dW) in the Landrace X Desi synthetic piglet population reared under sub-temperate agro climatic region of India. The data were analyzed using restricted maximum likelihood (REML) fitting six animal models with various combinations of direct and maternal effects. Estimates of genetic and permanent environmental correlations were obtained using bivariate analysis of an animal model and computed with the DFREML program. A log likelihood ratio test was used to select the most appropriate univariate model for each trait. The direct estimates of heritability were 0.43 ± 0.04, 0.31 ± 0.04, 0.35 ± 0.05, 0.40 ± 0.06, and 0.49 ± 0.06 for BW, 14dW, 28dW, 42dW, and 56dW, respectively and it increased with age from 14dW to 56dW. The permanent litter effect progressively decreased and was minimum at 56dW, ranged from 0.21 ± 0.06 to 0.34 ± 0.04. Further, maternal genetic heritability was the highest, ranging from 0.16 ± 0.07 (model 5) to 0.18 (model 6), at age of weaning and the lowest for BW, from 0.04 ± 0.03 (model 5) to 0.06 (model 6). The presence of permanent litter effect was more important since it increased the accuracy of last three models (models 4-6) significantly over the first three models (models 1-3) without permanent litter effect. The selection of 56dW would be more reliable for genetic progress rather than the selection of BW. The direct additive genetic correlation (r a ) between BW and 56dW was −0.158 ± 0.29 which revealed that higher BW may not result for favorable changes in weaning weights which was in contradiction to many earlier reports.

Vibriosis is regarded as an important disease of penaeid shrimps affecting larvae in hatcheries. Among the Vibrio species, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio furnissii, Vibrio campbellii, Vibrio harveyi, Vibrio alginolyticus, and Vibrio anguillarum are often associated with diseases in finfish and shellfish of brackishwater ecosystem. Accurate species differentiating methods for the organisms present in an ecosystem are required for precise classification of the species and to take steps for their management. Conventional methods like 16s rRNA phylogeny and multilocus sequence typing (MLST) have often failed to correctly identify Vibrio species. This has necessitated a comprehensive investigation on methodologies available to distinguish Vibrio species associated with brackishwater aquaculture system. To achieve this, 35 whole genomes belonging to 7 Vibrio species were subjected to phylogenetic analysis based on 16s rRNA gene, MLST genes, single-copy orthologous genes, and single-nucleotide polymorphisms. In addition, genome-based similarity indices like average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) were computed as confirmatory tests to verify the phylogenetic relations. There were some misclassifications occurred regarding phylogenetic relations based on 16s rRNA genes and MLST genes, while phylogeny with single-copy orthologous genes produced accurate species-level clustering. Study reveals that the species identification based on whole genome-based estimates or genome-wide variants are more precise than the ones done with single or subset of genes.

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