Effect of dietary isoleucine level on growth,protein retention efficiency,haematological parameter,lysozyme activity and serum antioxidant status of fingerling Channa punctatus (Bloch)

Isoleucine requirement of fingerling Channa punctatus (6.74 ± 0.09 g) was estimated by feeding seven trial diets (450 g/kg CP, 14.73 kJ/g DE) containing 3.8, 7.5, 11.3, 15.1, 19.3, 23.2 and 27.4 g/kg of isoleucine for 12 weeks. Growth and haematological parameters increased with the increasing concentrations of dietary isoleucine up to 16 g/kg. Carcass protein and fat increased significantly with the increasing concentrations of dietary isoleucine up to 16 g/kg and then stabilized. Moisture content showed reverse trend to that of carcass fat. Hepatosomatic index was found to be highest at 4 g/kg of dietary isoleucine. Viscerosomatic index and condition factor increased significantly with increasing levels of isoleucine up to 16 g/kg dry diet. Serum protein, lysozyme and superoxide dismutase activities were also found to increase significantly up to 16 g/kg dry diet. Significant reduction in alanine aminotransferase and aspartate aminotransferase activities was observed by increasing concentrations of dietary isoleucine up to 16 g/kg. Based on quadratic regression analysis of absolute weight gain, feed conversion ratio, protein retention and isoleucine retention efficiencies against varying concentrations of isoleucine, the optimum isoleucine requirement ranging between 17.95 and 18.39 g/kg dry diet, corresponding to 39.88–40.86 g/kg dietary protein, is recommended for maximizing growth of C. punctatus.     

Agro-Morphological,Physico-Chemical and Molecular Characterization of Rice Germplasm with Similar Names of Bangladesh

Thirty-one duplicate and similar named rice germplasms of Bangladesh were studied to assess the genetic variation for the agro-morphological and physico-chemical traits and simple sequence repeat banding patterns during 2009–2012 at Bangladesh Rice Research Institute. The range of variations within the cultivar groups showed higher degree. The principal component analysis showed that the first five components with vector values 1 contributed 82.90% of the total variations. The cluster analysis grouped the genotypes into four clusters, where no duplicate germplasm was found. The highest number(11) of genotypes was constellated in cluster I and the lowest(3) in cluster II. The intra- and inter-cluster distances were the maximum in cluster I(0.93) and between clusters I and IV(24.61), respectively, and the minimum in cluster IV(0.62) and between clusters I and III(5.07), respectively. The cluster mean revealed that the crosses between the genotypes of cluster I with those of clusters II and IV would exhibit high heterosis for maximum good characters. A total of 350 alleles varied from 3(RM277) to 14(RM21) with an average of 7.8 per locus were detected at 45 microsatellite loci across the 31 rice accessions. The gene diversity ranged from 0.48 to 0.90 with an average of 0.77, and the polymorphism information content values from 0.44(RM133) to 0.89(RM206) with an average of 0.74. RM206, RM21, RM55, RM258 and RM433 were considered as the best markers on the basis of their higher polymorphism information content values. The dendrogram from unweighted pair-group method with arithmetic average clustering also classified the genotypes into four groups, where group IV comprised of 20 genotypes and group III of one genotype, but no duplicate was found. Finally, similar and duplicate named rice germplasms need to be conserved in gene bank as are distinct from each other.