Growth performance, meat yield and blood lipid profile of broiler and Sonali chickens.

A total of 14,200, day-old broiler chicks were allotted into two batches (B1=Winter and B2 = Summer) with 6 replicates each for 30 days, and 16,000, day-old Sonali chicks were allotted into 2 batches with 4 replicates each for 60 days to assess the growth performance, meat yield, and lipid profiles of the blood of chickens. Broiler chickens showed significantly higher body weight, feed intake, and lower FCR and production cost with a tendency to increase mortality compared with Sonali chickens. However, net profit tended to be higher in Sonali chickens compared to broiler chickens. The higher meat yield traits were observed in the broiler chicken compared with the Sonali chicken (p<0.001). Lipid profile did not differ (p>0.05) between chicken types. However, lipid profiles tended to be higher in broiler chicken than in Sonali chicken, except for the low-density lipoprotein (LDL). Growth performance, meat yield traits, and lipid profiles did not differ (p>0.05) between batches, except for the dressing percentage. Dressing (%) was higher in B1 than in B2 (p<0.05). No interaction between batch and chicken type was found in the growth performance, meat yield, and blood lipid profile of chickens. Therefore, broiler chickens performed better than Sonali chickens in terms of growth and meat yield traits. Nevertheless, Sonali chickens tended to perform better than broilers in terms of consumer preference, net profit, and lowering total cholesterol and triglyceride. However, more studies are needed to confirm the present findings and make the suggestion to use a suitable chicken type for meat production.

Genetically Diverse Low Pathogenicity Avian Influenza A Virus Subtypes Co-Circulate among Poultry in Bangladesh.

Influenza virus surveillance, poultry outbreak investigations and genomic sequencing were assessed to understand the ecology and evolution of low pathogenicity avian influenza (LPAI) A viruses in Bangladesh from 2007 to 2013. We analyzed 506 avian specimens collected from poultry in live bird markets and backyard flocks to identify influenza A viruses. Virus isolation-positive specimens (n = 50) were subtyped and their coding-complete genomes were sequenced. The most frequently identified subtypes among LPAI isolates were H9N2, H11N3, H4N6, and H1N1. Less frequently detected subtypes included H1N3, H2N4, H3N2, H3N6, H3N8, H4N2, H5N2, H6N1, H6N7, and H7N9. Gene sequences were compared to publicly available sequences using phylogenetic inference approaches. Among the 14 subtypes identified, the majority of viral gene segments were most closely related to poultry or wild bird viruses commonly found in Southeast Asia, Europe, and/or northern Africa. LPAI subtypes were distributed over several geographic locations in Bangladesh, and surface and internal protein gene segments clustered phylogenetically with a diverse number of viral subtypes suggesting extensive reassortment among these LPAI viruses. H9N2 subtype viruses differed from other LPAI subtypes because genes from these viruses consistently clustered together, indicating this subtype is enzootic in Bangladesh. The H9N2 strains identified in Bangladesh were phylogenetically and antigenically related to previous human-derived H9N2 viruses detected in Bangladesh representing a potential source for human infection. In contrast, the circulating LPAI H5N2 and H7N9 viruses were both phylogenetically and antigenically unrelated to H5 viruses identified previously in humans in Bangladesh and H7N9 strains isolated from humans in China. In Bangladesh, domestic poultry sold in live bird markets carried a wide range of LPAI virus subtypes and a high diversity of genotypes. These findings, combined with the seven year timeframe of sampling, indicate a continuous circulation of these viruses in the country.

Multiple reassortment events among highly pathogenic avian influenza A(H5N1) viruses detected in Bangladesh.

In Bangladesh, little is known about the genomic composition and antigenicity of highly pathogenic avian influenza A(H5N1) viruses, their geographic distribution, temporal patterns, or gene flow within the avian host population. Forty highly pathogenic avian influenza A(H5N1) viruses isolated from humans and poultry in Bangladesh between 2008 and 2012 were analyzed by full genome sequencing and antigenic characterization. The analysis included viruses collected from avian hosts and environmental sampling in live bird markets, backyard poultry flocks, outbreak investigations in wild birds or poultry and from three human cases. Phylogenetic analysis indicated that the ancestors of these viruses reassorted (1) with other gene lineages of the same clade, (2) between different clades and (3) with low pathogenicity avian influenza A virus subtypes. Bayesian estimates of the time of most recent common ancestry, combined with geographic information, provided evidence of probable routes and timelines of virus spread into and out of Bangladesh.