Evaluation of Microbial Quality of Raw Milk into two Dairies Mitidja’s Farms (Algeria)

Abstract

The aim of this study was to investigate the microbial quality of raw milk into two dairiesfarms of Mitidja (Algeria), in relation with the herd size and milking hygiene (before and afterdisinfecting the udder). Total 40 individual raw milk samples against 8 mixed were collected. Inaddition, 62 rinses udder tegument and raw milk samples were also taken, in order to detectCryptosporidia oocysts and antimicrobial residues. Total Bacterial Count (TBC), Total and FecalColiforms (TC and FC) counts in individual raw milk were higher in large farm than in the small one.In contrast, mixed milk appeared more loaded with TBC and Coliforms than in the individual milk(microbial load exceeded more 105 cfu ml-1). However, the means numbers of TBC and Coliformswere reduced considerably after disinfecting udder in each farm. However, the risk of bacterialcontamination was also decreased significantly after cleaning and disinfecting the udder in both farms,from 11 to 3 positives cases for E. coli, 7 to 1 for Anaerobic Sulfito-Reducing (ASR) and 5 to 1 forStaphylococcus aureus. In contrast, Salmonella and Yeasts were not reduced after disinfecting udder.Cryptosporidia were mostly isolated from udder tegument than in raw milk, 10 vs 3 contaminationsrespectively. In addition, the disinfection seems to minimize their presence in udder tegument (9 vs 1contamination) and in raw milk (3 against none contamination). Finally, none of raw milk samplescontains antimicrobial residues.