Antibiotic residues in raw milk produced in Commercial farms Unguja, Zanzibar

Abstract

Background: Dairy farming is one among the major sources of income for most of the people in Zanzibar.Although dairy production has been improved, there are a number of challenges facing milk industry in the island. There are no specific strategies to ensure that the milk at the farm level and that found at the marketing system is free from chemical agents. Equally, little is known regarding the level of knowledge to farmers and consumers on effects of antibiotic residues and resistance and factors associates with antibiotic residues in milk. Objectives: To determine the proportion of antibiotic residues and its associated factors in raw milk production in commercial farms in Unguja, Zanzibar. Methodology: A cross-sectional study was conducted in Unguja between March to June 2020. A total of 136 farmers were included in this study from which 272 composite milk samples were collected from their farms. Information on farmers’ knowledge to raw milk safety in particular antibiotic residues, practices related to raw milk safety and main factors associated to antibiotic contamination in milk was collected. Bivariate and multivariate analysis logistic regression was used to identify factors associated with antibiotic residues in raw milk. Result. About half (49.6%) of the milk samples were positive with antibiotic residues. Only 25% percent adhere to withdrawal period. The risk of producing milk contaminated with antibiotic residues was almost 3 times more in farmers who do not have knowledge on withdrawal period compared to those who have knowledge although it was not statistically significant [AOR=2.82 95% CI=0.57-13.87, P- value 0.19]. Likewise, the risk of producing milk contaminated with antibiotic residues was almost three times higher in those farmers who obtained drugs from private drug sellers compared to those who obtained drugs from vet professionals although not statistically significant [AOR=2.81 95% CI=0.50-15.87, P-value 0.24]. Moreover, farmers who received training on drug administration were 2 times less risky in producing antibiotic contaminated milk than those who did not receive training, although was not statistically significant AOR=2.10 [ 0.54-8.11, P-value 0.27]. Conclusion: About half of the milk samples obtained from famers had antibiotic residues. In addition, it was apparent that most farmers had limited knowledge and practices with regard to adhering to withdrawal period, understanding health effects on antibiotic residues consumption and milk safety and hygiene. Obtaining drugs from private drug sellers was alsoassociated with antibiotic residues in milk. Specific strategies are therefore required to ensure that the milk at the farm level and that found at the marketing system is free from antibiotic residues.