Perfil do leite cru de propriedades produtoras do município de Bacabal/MA: análises microbiológicas, físico-químicas, resistência de bactérias patogênicas a antimicrobianos e resíduos de antibióticos.

Abstract

In Maranhão, there is a significant increase in milk production, with levels of productivity still far from its productive potential. In the municipality of Bacabal, there is a significant number of properties, but there are few data and studies on their production profile. Therefore, this study aimed to study the profile of raw milk from producing properties in the municipality of Bacabal / MA, using as parameters the microbiological, physical-chemical analyzes, resistance of pathogenic bacteria to antimicrobials and the presence of antibiotic residues. Five properties called F1, F2, F3, F4 and F5 were analyzed. The analyzes of physical-chemical quality were acidity, relative density, fat, total dry extract (TDE), defatted dry extract (DDE), lactose and protein. The microbiological analyzes performed were the count of the most likely number of total coliforms, thermotolerant coliforms and the standard plate count for positive coagulase and negative coagulase and Salmonella, according to the methodology described by APHA (2017). The resistance and sensitivity profile of Staphylococcus followed the disc diffusion method. The antimicrobials used were: gentamicin (10µg), ampicillin (10µg), cephalothin (30µg), penicillin G (10µg), oxacillin (lµg), chloramphenicol (30µg), erythromycin (15µg). To measure the inhibition halos, a millimeter ruler was used. The species were classified according to the halo size as sensitive (S), intermediate (I) and resistant (R). The presence of residue was detected using the Eclipse 50 Kit. The physical-chemical and microbiological results are in the standards required by current legislation, with the exception of two farms that had an average acidity above those required by IN 76: farms F4 (18.4 ° D) and F5 (20.3 ° D). Bacteria of the coliform group, E. coli (F3 and F4), Enterobacter aerogenes (F1) and Klebisiella pneumoniae (F1), Staphylococcus and absence of Salmonella were found. The isolated Staphylococcus species were mostly coagulase negative, with the following species being identified: S. capitis, S. caseolytiocus, S. cloosii, S. lentus, S. xylosus. The presence of S. aureus was detected only on the F5 farm. The presence of residue was observed in 80% of the properties. In the resistance evaluation, 100% resistance of the strains was observed for ampicillin, penicillin and oxacillin. In sequence, there are cephalothin and gentamicin, both with 50% and erythromycin with 25%. Sensitivity of 100% of the strains to chloramphenicol, 50% to gentamicin and 40% to erythromycin was observed. Multidrug resistance was observed in the species S. aureus and S. xylosus. In general, the farms studied present a milk within the standards required by the legislation, however, the high counts of microorganisms, presence of residues and multidrug resistance constitute a potential danger to public health and awareness and prophylaxis actions should be adopted for improvement of the quality of the milk produced in the municipality of Bacabal / MA. Keywords: