What’s in the milk? : aflatoxin and antibiotic residues in cow’s milk in Assam, Northeast India

Sammanfattning: Worldwide, there are increasing concerns about food safety and what is really present in the food we are eating, and feeding our children. Antibiotic residues are one of these concerns and a growing global problem. In 2001 India became the world’s largest consumer of antibiotics and the problem with antibiotic resistance is increasing. Studies have shown a link between a high SCC (somatic cell count) in cow’s milk and high risk for antibiotic residues. In India reports have shown that the average number of clinical mastitis is between 3.94% and 23.25% of the total cow population. In additions to antibiotic residues, there is a risk of mycotoxins in milk products. In countries with a tropical climate such as India, problems due to chronic exposure of aflatoxins are emerging. The fungi that produce the toxin, Aspergillus spp., thrive in a hot and humid climate. The effects of chronic aflatoxin exposure include liver carcinoma, and potentially immune suppression and stunting, with children being the most susceptible. In 2009 the International Livestock Research Institute (ILRI) started a project together with local partners to enhance the local informal milk sector in Guwahati, Assam, northeast India. The project involved a training program for milk producers and milk vendors. The project finished in 2013. The objective of this study is to make a follow up on as well as an evaluation of the ILRI project. Trained and untrained farmers were interviewed from a questionnaire, in order to assess the knowledge, attitudes and practices. In addition, milk samples were selected from 25% of the lactating cows on the farms. The milk samples were tested to examine the level of antibiotic residues and aflatoxin in the milk. Of the farmers who participated in this study 74 had received previous hygiene training by ILRI and 76 had not. Both trained and untrained farmers had in average 12 lactating cows. In both trained and untrained farms most of the feeding and caring of the cows was done by the farmer and his/her family members. The overall knowledge about zoonotic pathogens and toxic substances was low. Farmers who had received previous hygiene training by ILRI showed significant higher levels of knowledge (p-value <0.001) than farmers who had not. This was tested by summarizing the results on a number of questions regarding the farmers’ knowledge about zoonotic pathogens, toxins and general food safety. The trained farmers had a mean test score of 9.95 and the untrained 8.16. A rapid testing platform, Charm EZ, was used to test milk samples for residues of Neomycin and Streptomycin, Sulphonamides, -lactams, Quinolones, Chloramphenicol, Macrolides and Gentamicin, Tetracycline. 88.6% of the collected milk samples tested positive for Neomycin and Streptomycin, the second most common was Sulphonamides that was found in 22.8% of the samples. The results were not significantly different between the trained and untrained group. The same system was used to test for aflatoxins. 4.5% of the tested milk samples showed a positive result for aflatoxin. The level for a positive result was 500ng/kg which is the limit stated by the U.S. food and drug administration (FDA), Codex Allimentarius and the food safety and standards authority of India (FSSAI). The trained farms had statistically significant more positive samples than the untrained ones (p-value 0.03), which may be explained by the slightly higher milk yield in the trained farms and the presumably higher use of concentrate in the cows’ feed. It is suggested that hygiene training as well as education is implemented to raise the overall knowledge about zoonotic pathogens, toxins and general food safety.