Antibiotic residues in raw and pasteurized milk, Iran

Consumption of food products of animal origin with residual antibiotic has become a major concern of public health and dairy industry. In the study, antibiotic residue in raw and pasteurized milk was investigated. Of the 9 semi-industrial farm units, random on 3 occasions sampling was carried out from 4 milk collection stations and 3 pasteurized milk producing companies, and antibiotic residue was analyzed using Copan Milk Test method. The results showed that of the 96 samples collected, 28 (29.16%) were positive in terms of presence of antibiotics residue. Analysis of milk samples taken in spring and in summer showed a significant difference in antibiotic residue content, such that samples taken in summer contained higher percentage of antibiotic residue (37.5%) compared to samples taken in spring (20.83%). Contamination of raw milk samples (30.76%) with antibiotic residue was significantly higher than that in pasteurized milk samples (22.2%). Given the adverse effects of consumption of contaminated milk with antibiotic residues and huge losses to dairy industry, it seems more comprehensive studies are needed to ascertain precise types of antibiotic residues in milk consumed in this field.