Microbiological Safety of Raw Sheep’s Milk and Cheese Produced in Southern Brazil: An Evaluation of Enterotoxins and Antimicrobial Resistance in Isolated Staphylococcus Species

This work highlights that monitoring the microbiological quality of animal products, such as raw sheep’s milk and cheese, is necessary for food safety. Sheep’s milk and its derivatives are not legislated in Brazil. Thus, present study aimed to evaluate: (i) the hygienic-sanitary quality of raw sheep’s milk and cheese produced in southern Brazil; (ii) the presence of enterotoxins and Staphylococcus spp. in these products; and (iii) the antimicrobial susceptibility profile and resistance genes of the isolated Staphylococcus spp. Thirty-five raw sheep’s milk and cheese samples were evaluated. Microbiological quality and the presence of enterotoxins were determined by Petrifilm and VIDAS SET2 methods, respectively. Antimicrobial susceptibility tests were conducted using VITEK 2 equipment and the disc diffusion method. The presence of resistance genes tet(L), sul1, sul2, ermB, tetM, AAC(6)', tetW, and strA were evaluated by PCR. In total, 39 Staphylococcus spp. were isolated. The tetM, ermB, strA, tetL, sul1, AAC(6)’, and sul2 resistance genes were detected in 82%, 59%, 36%, 28%, 23%, 3%, and 3% of isolates, respectively. The results showed that both products contained Staphylococcus spp. and these strains were resistant to antimicrobials as well carriers of resistance genes. These results highlight Brazil's need for specific legislation regarding the pro-duction and marketing of these products.