Evaluation of Biosecurity Practices and Resistance Phenotypes of Escherichia coli in Dairy Cattle Farms in Nyagatare, Rwanda

ABSTRACT Background: Biosecurity is a comprehensive approach aimed at preventing the occurrence and spread of infectious diseases within livestock farms. It plays a vital role in safeguarding animal health, ensuring food safety, and minimizing the transmission of diseases from animals to humans. Meanwhile, antimicrobial resistance (AMR) poses a significant threat to public health and animal medicine, as it compromises the effectiveness of antibiotics in treating infections. Certain strains of Escherichia coli (E. coli) found in dairy cattle have been identified as priority pathogens due to their potential to cause severe health issues. Currently, there is limited or no information available on the levels of biosecurity in dairy cattle farms and the prevalence of AMR in E. coli strains in Rwanda. Hence, this study aimed to assess the biosecurity levels in dairy cattle farms, determine the prevalence of AMR in E. coli and explore possible associations between biosecurity and AMR. Methods: A cross-sectional study was conducted in the Nyagatare district of the Eastern province of Rwanda between the period of May to June 2023. Biosecurity levels of 160 randomly sampled dairy cattle farms were assessed using a modified Biocheck Ughent questionnaire while standard CLSI procedures were used to identify E. coli isolates from samples collected and determine their antimicrobial susceptibility. Data collected on farmers’ demographics, farm characteristics, biosecurity levels, and antimicrobial resistance was quantitatively analyzed using SPSS Version 20. Chi-square tests and logistic regression analysis were used for tests of association between variables and the P-value set at <0.05 was considered for statistical significance. Results: The study found low biosecurity practices in dairy cattle farms, with only 1.9% practicing teat cleaning before and after milking. Only 9.4% of farmers maintained a register of animal health data. External biosecurity measures, such as quarantine and testing, were implemented by 63.1% and 63.8%, of farms respectively. However, personal protective equipment and hygienic practices for visitors and workers were significantly lacking. Out of 106 biosecurity practices assessed, results showed that biosecurity scores varied among farms, with the highest score being 50% and the lowest being 11%. Farms were observed to perform better in external biosecurity (median 34.7%) compared to internal biosecurity (median 22.8%). Overall, 51.9% of farms had fair biosecurity levels while 46.9% of them had poor biosecurity levels. Results revealed that Gender ,the Age of respondents , Training, and Education levels were not found to be significantly associated with any of the biosecurity levels. Isolates displayed varying levels of resistance to different antibiotics. Ceftazidime exhibited the highest resistance rate at 91.7%, followed by Amoxicillin at 66.7%, Trimethoprim at 25%, Tetracycline, and Ampicillin at 20.8%, Ciprofloxacin at 16.5%, and Cefepime at 12.5%. isolates showed high sensitivity to Imipenem and Gentamicin, both at 100%, followed by Cefuroxime at 95.8%, Meropenem at 91.7%, Augmentin at 87.5%, Trimethoprim, and Tetracycline at 75%, and Ampicillin at 75%. Out of the E. coli isolates with significant Multiantibiotic resistance (MAR) indexes, 63% were found in houses with poor biosecurity. Conclusion: The study highlights poor implementation of biosecurity practices and the presence of resistant E. coli phenotypes in studied dairy farms. These findings underscore the need for improved biosecurity practices in dairy cattle farms to mitigate the risk of AMR development and transmission. Enhancing biosecurity measures, such as teat cleaning, maintaining animal health records, and providing PPE for visitors and farm workers, is crucial for sustainable agriculture, the reduction of AMR prevalence, food safety, and the overall protection of public health.