The continuous use of antibiotics in compound feed at sub-therapeutic level has been an integral part of commercial poultry production in Nepal, which is one of the factors that promotes bacterial resistance. Hence, with the objective to determine antibiotic resistance in commercial poultry of Nepal, this study was designed taking Escherichia coli as a flagship bacterium. The commercial layers and broilers birds brought to veterinary teaching hospital of Agriculture and Forestry University by commercial poultry producers for disease diagnosis and treatment were considered as clinical examination of birds were carried out followed by post mortem examination (PME). Those layer/broiler birds which were not taking antibiotic orally or parenterally for last 2 weeks and diagnosed with collibacillosis on PME were included in sampling frame. Air sacculitis, fibrinous pericarditis, fibrinous perihepatitis, and coligranuloma were major criteria for presumptive diagnosis of colibacillosis on PME. The first 40 for both broiler and layer birds totaling 80 that fulfilled the criteria were selected as samples, each representing a commercial farm. All necessary information on daily management practices and previous treatments were obtained from farmer's record book or sheets or face to face interview. Avian pathogenic E. coli was isolated from aseptically collected liver samples and confirmedby biochemical tests. Antibiogram of the isolates were investigated by means of Kirby-Bauer disc diffusion method. E. coli was isolated from all liver samples taken for the culture. It was found that E. coli were resistant most substantially towards Cephalexin (81.2%) and Amoxycillin (81.2%) followed by Tetracycline (78.8%), Colistin sulphate (n=50, 62.5%). Chloramphenicol (61.2%), Ciprofloxacin (55.0%), Enrofloxacin (53.8%), Levofloxacin (28.8%), however, no resistance was found against amikacin. The proportion of E. coli isolates that were resistance against Colistin sulphate (p<0.05), Chloramphenicol (p< 0.05), Tetracycline (p<0.001), Ciprofloxacin (p<0.01), Enrofloxacin (p<0.05) and Gentamicin (p<0.01) were significantly higher in layers compared to that of broilers. In conclusion, avian pathogenic E. coli were resistant towards several antibiotic molecules commonly used in commercial poultry of Nepal, and the resistance was higher in layers compared to broilers.

Context. Genetic evaluation of Australian sheep is conducted for millions of animals for more than 100 traits. Currently, the Australian sheep genetic-analysis software (OVIS) applies a pre-adjustment of phenotype for fixed effects rather than fitting all fixed and random effects jointly in a linear mixed model to estimate breeding values. However, the current correction factors might be outdated and potential interactions among fixed effects not accounted for, which could lead to bias in estimated breeding values (EBVs). Aims. This study aimed to assess whether correction factors used in OVIS for early bodyweights recorded in meat sheep breeds are appropriate, so as to explore whether the pre-adjustment method is still suitable and how this compares with a linear mixed model, and to estimate the significance of interactions between fixed effects. Methods. Correlations between EBVs from different models and regression slopes from forward prediction were calculated, using weaning-weight data on 365 956 White Suffolk and 370 649 Poll Dorset sheep and post-weaning weight data on 292 538 White Suffolk and 303 864 Poll Dorset sheep. Key results. The current OVIS procedure resulted in regression slopes of progeny performance on sire EBVs (averaged over breeds) of 0.37 and 0.35 for weaning and postweaning weights respectively. Updated pre-adjustment factors improved the regression slopes to 0.40 and 0.38 respectively. Analysis with a linear mixed model produced significantly better regression slopes than did pre-adjustment (0.47 and 0.44 respectively). Further, regression slopes obtained from the linear mixed model with flock by sex by age interaction averaged over breeds were 0.48 for weaning and 0.46 for post-weaning weight respectively, which was a moderate improvement over the current OVIS model. Including a flock by sex by age interaction produced significantly better improvement in Poll Dorset sheep and modest improvement in White Suffolk sheep than did linear mixed model without interaction. Conclusions. Using a linear mixed model with a flock by sex by age interaction significantly improves the utility of estimated breeding values for weaning and post-weaning weight in predicting the performance of future progeny. Implications. To account for systematic environmental effects, a linear mixed model should be used in OVIS to jointly estimate the fixed effects and EBVs.

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A study was conducted in major milk pocket area of Chitwanand Nawalparasi districts with the objective of assessing productive performance of dairy cattle reared in those areas. The study also aimed at categorizing the breed based on its breeding value to determine the most elite cow of different breeds.Four years of data send obtained from Animal Breeding Division in the period between (2008-2012) under the Dairy Cattle Improvement Program were reviewed and analyzed. Altogether, 18316 test day records of 728 animals of 172 herds were considered for evaluation. Results of the above study revealed that the overall least square mean and standard errors (LS mean and SE) of Lactation Milk Yield (LMY), fat percentage, and protein percentage were 2841±84.95 kg, 4.43±0.66 % and 3.33±0.1 %, respectively. Moreover, the study also revealed that breed had significant effect on milk yield (p<0.001), protein percentage (p< 0.01) and Fat percentage (p< 0.001). In addition, top dairy cattle are ranked based on its breeding value on productive parameters. Results of the above study suggested that animal of higher breeding value and it's offspring need to be promoted for better productivity in farmer managed condition of Nepal.Journal of the Institute of Agriculture and Animal Science. Vol. 33-34, 2015, page: 207-212