Factores asociados a la presencia de residuos antibióticos en leche cruda de vacas en el cantón El Carmen, Manabí, Ecuador.

Milk, an essential component of human nutrition, can also serve as a vehicle for external contaminants such as antibiotics. To date, no data are available regarding the presence of antibiotic residues in raw milk from El Carmen (Manabí), the largest dairy basin on the Ecuadorian coast. Therefore, the objective of this study was to determine the presence of these residues and the associated risk factors. A total of 126 raw milk samples were collected from 42 dairy farms on three different occasions between September 2022 and January 2023. Of these, 78.57% (99/126) contained antibiotic residues below the maximum limits established by the Codex Alimentarius, whereas 21.43% (27/126) exceeded these limits. Sulfonamides were the most frequently detected residues (15.57%), followed by β-lactams (4.76%) and tetracyclines (0.79%). Among the risk factors analyzed, the frequency of antibiotic use in animals per year had the greatest influence (Odds Ratio: 0.001), compared with other covariates. The findings indicate a high prevalence of antibiotic residues in raw milk from the sampled region, primarily due to the indiscriminate use of these drugs by dairy farmers. Therefore, the role of regulatory agencies is crucial in preventing the commercialization of milk containing these residues. Additionally, training programs for producers are essential to mitigate this form of chemical contamination.