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Background: Bovine genital campylobacteriosis (BGC) is a venereal disease caused by Campylobacter fetus that has a negative impact on animal reproduction. The bull is considered to be a symptomless carrier that spreads the disease agent to breeding cows, causing infertility and sporadic abortion. Aim: The study aims to estimate the prevalence, identify risk factors of Campylobacter fetus (C. fetus) infection and antimicrobial resistance pattern of the C. fetus isolates. Method: A cross‐sectional survey was conducted in Mymensingh district of Bangladesh. Bull smegma samples (single sample from each bull) were collected from 300 bulls from four farms and tested via culture, biochemical identification and finally 16S rRNA and cdtA gene‐based molecular assays (PCR) for herd and animal‐level prevalence estimation. Herd‐ and animal‐level data on risk factors were collected from the farmers using a pretested questionnaire and analysed by univariable and multivariable logistic regression models with a p value of <0.05 was taken statistically significant for both analyses. Results: Among the surveyed farms, 75% (95% CI: 19.4%–99.4%) were confirmed to have bulls infected with Campylobacter fetus at herd level. However, animal‐level occurrence of C. fetus was estimated to be 8.7% (26/300) (95% CI: 5.7%–12.4%). Natural service increases the odds of campylobacteriosis 38.18 times (95% CI: 13.89–104.94) in comparison to artificial insemination for C. fetus infection in bulls. Significantly, half of the isolates (50%, n = 13) were identified to be multidrug resistant (MDR) for three to five antimicrobial agents. Conclusion: This study highlights the need to develop official guidelines for C. fetus control and prevention in Bangladesh including mandatory artificial insemination in reproductive cows and heifers, routine screening of breeding bulls for C. fetus free status. [ABSTRACT FROM AUTHOR]

Over the years, the emergence of novel H5 and H7 highly pathogenic avian influenza viruses (HPAI) has been taking place through two main mechanisms: first, the conversion of a low pathogenic into a highly pathogenic virus, and second, the reassortment between different genetic segments of low and highly pathogenic viruses already in circulation. We investigated and summarized the literature on emerging HPAI H5 and H7 viruses with the aim of building a spatio-temporal database of all these recorded conversions and reassortments events. We subsequently mapped the spatio-temporal distribution of known emergence events, as well as the species and production systems that they were associated with, the aim being to establish their main characteristics. From 1959 onwards, we identified a total of 39 independent H7 and H5 LPAI to HPAI conversion events. All but two of these events were reported in commercial poultry production systems, and a majority of these events took place in high-income countries. In contrast, a total of 127 reassortments have been reported from 1983 to 2015, which predominantly took place in countries with poultry production systems transitioning from backyard to intensive production systems. Those systems are characterized by several co-circulating viruses, multiple host species, regular contact points in live bird markets, limited biosecurity within value chains, and frequent vaccination campaigns that impose selection pressures for emergence of novel reassortants. We conclude that novel HPAI emergences by these two mechanisms occur in different ecological niches, with different viral, environmental and host associated factors, which has implications in early detection and management and mitigation of the risk of emergence of novel HPAI viruses.