Molecular epidemiology and pathogenicity of H5N1 and H9N2 avian influenza viruses in clinically affected chickens on farms in Bangladesh.

Avian influenza virus (AIV) subtypes H5N1 and H9N2 co-circulate in poultry in Bangladesh, causing significant bird morbidity and mortality. Despite their importance to the poultry value chain, the role of farms in spreading and maintaining AIV infections remains poorly understood in most disease-endemic settings. To address this crucial gap, we conducted a cross-sectional study between 2017 and 2019 in the Chattogram Division of Bangladesh in clinically affected and dead chickens in farms with suspected AIV infection. Viral prevalence of each subtype was approximately 10% among farms for which veterinary advice was sought, indicating high levels of virus circulation in chicken farms despite the low number of reported outbreaks. Co-circulation of both subtypes was common in farms, with our findings suggest that in the field, the co-circulation of H5N1 and H9N2 can modulate disease severity, which could facilitate an underestimated level of AIV transmission in the poultry value chain. Finally, using newly generated whole-genome sequences, we investigate the evolutionary history of a small subset of H5N1 and H9N2 viruses. Our analyses revealed that for both subtypes, the sampled viruses were genetically most closely related to other viruses isolated in Bangladesh and represented multiple independent incursions. However, due to lack of longitudinal surveillance in this region, it is difficult to ascertain whether these viruses emerged from endemic strains circulating in Bangladesh or from neighbouring countries. We also show that amino acids at putative antigenic residues underwent a distinct replacement during 2012 which coincides with the use of H5N1 vaccines.

Improvement of DVM Curriculum to Meet OIE Recommendations at Chattogram Veterinary and Animal Sciences University, Bangladesh.

A veterinary education twinning project between Chattogram Veterinary and Animal Sciences University (CVASU) and Tufts Cummings School of Veterinary Medicine (TCSVM) was supported by the World Organisation for Animal Health (OIE) to align CVASU's veterinary curriculum with OIE's recommended Core Curriculum and Day 1 Competencies. The major objectives were curriculum development with improvement to the internship program, introduction of problem-based learning (PBL), and implementation of continuing education (CE). Major activities to achieve these objectives involved several workshops and seminars at CVASU and establishing student exchange and CVASU faculty training programs. Major accomplishments were (a) implementation of a revised Doctor of Veterinary Medicine (DVM) curriculum at CVASU aligned with the OIE-recommended curriculum and Day 1 Competencies; (b) incorporation of PBL into the curriculum and development of 23 PBL cases relevant to Bangladesh-specific diseases; (c) improvement of the internship program by including Day 1 Competencies; (d) development and implementation of 11 structured CE sessions including hands-on training; (e) improvement of curriculum, teaching, and clinical training at CVASU following training of CVASU faculty and students at TCSVM; and (f) three peer-reviewed publications from summer research projects by TCSVM students at CVASU. The twinning project allowed CVASU to improve its DVM curriculum by aligning with OIE's recommended curriculum and Day 1 Competencies. The impact of the project went beyond CVASU as evidenced by other veterinary schools adopting the CVASU curriculum and PBL, veterinary school deans engaged in improving veterinary curriculum and clinical training, and implementation of a national CE program for veterinarians.

Antibiotic residues in milk and eggs of commercial and local farms at Chittagong, Bangladesh.

AIM: The study was conducted to detection and determination of concentration or level of antibiotic residues in milk and egg of local and commercial farms at Chittagong during December 2011 to June 2012. MATERIALS AND METHODS: A total of 400 (200 milk and 200 egg) samples were collected from local and commercial dairy cows and local scavenging and commercial poultry farms, respectively. Microbial inhibition test and thin layer chromatography were used for screening and ultra-high performance liquid chromatography was used to estimate the concentrations of antibiotic residues in samples. RESULTS: Tetracycline, amoxicillin, and ciprofloxacin residues were significantly (p ≤ 0.05) higher in commercial farms than local. The boiling insignificantly (p>0.05) reduced residues level in milk and egg. The average concentrations of amoxicillin residue in local milk, commercial milk, local egg, and commercial egg were 9.84 µg/ml, 56.16 µg/ml, 10.46 µg/g and 48.82 µg/g, respectively, in raw samples and were reduced to 9.81 µg/ml, 55.54 µg/ml, 10.29 µg/g, and 48.38 µg/g, respectively, after boiling. CONCLUSIONS: Proper maintaining of the withdrawal period and development of active surveillance system are highly recommended for public health security.

Determination of the presence and pharmacokinetic profile of ciprofloxacin by TLC and HPLC method respectively in broiler chicken after single oral administration.

The objective of this study was to determine the presence of ciprofloxacin and pharmacokinetics of ciprofloxacin in blood plasma of broiler chicken after single oral administration at feeding state. Ciprofloxacin was administered orally at 10 mg kg(-1) to each of the 10 broiler chickens at feeding state. Presence of ciprofloxacin was determined by TLC method and pharmacokinetics by HPLC method. Peak plasma concentration (Cmax) of ciprofloxacin, 0.26±0.03 mg l(-1) was achieved at 4.40±0.1 h (Tmax). Biological half-life of ciprofloxacin was 5.25±0.02 h. Area under the curve (AUC) was 13.397±0.13 mg ml(-1) h, elimination rate constant was 0.13±0.02 h(-1), volume of distribution was 0.194±0.04 l kg(-1) and bioavailability was 49±0.48%. On the basis of the results of the present study, we conclude that, feeding state may have a vital effect on the pharmacokinetic profile of ciprofloxacin in broiler blood plasma.

Pygomelia or supernumerary limbs in a crossbred calf.

A crossbred (Sindhi x local indigenous) calf that was 12 days old was admitted to the Teaching Veterinary Hospital, Chittagong Government Veterinary College, Bangladesh, with two accessory hind limbs attached to the pelvic region in between the hind legs. This was clinically identified as a congenital anomaly popularly called pygomelia. The pygomelia was successfully corrected by surgical excisions.