Pesquisa de genes toxigênicos em isolados de Staphylococcus aureus em amostras de leite de vacas na microrregião Garanhuns, estado de Pernambuco

Abstract

The objective of this work was to investigate the occurrence of encoding staphylococcal enterotoxin (sea, seb, sec and seg) genes and the toxin gene 1 of Toxic Shock Syndrome (tst) from Staphylococcus aureus, coming from mastitis cases bovine in the micro region of Garanhuns, State of Pernambuco. 93 isolates from Staphylococcus aureus were analyzed, which were obtained from milk samples from cows with clinical mastitis and subclinical from 17 properties in 11 municipalities of the Micro Region of Garanhuns, State of Pernambuco. For the molecular characterization of the species Staphylococcus aureus, one of the Polymerase Chain Reaction (PCR) was performed in order to identify the presence of the nuc gene, and to the molecular characterization of enterotoxins, and Staphylococcal toxin Toxic Shock Syndrome. Specific genes were identified: sea, seb, sec, seg and tst. 93 genes were analyzed and we observed the presence of enterotoxigenic gene in 20 (21.6%) samples, of which 11 (55.0%) were positive for tst gene, seven (35.0%) for the sec gene two (10.0%) for the seg gene. 20 isolates amplified segments to the presence of the sec, seg and tst genes. 16 of these (80.0%) were positive for only one gene, and four (20.0%) were positive for both genes (tst and sec). 17 properties were studied, of which seven (41.2%) had positive cultures for at least one of the genes sec, seg and tst. This was the first hit record of encoding gene of the toxin of toxic shock syndrome in mastitis cows milk samples in the state of Pernambuco. Since there was a variation in the distribution of sec, seg and tst genes in strains from different property, it can be inferred that there is genotypic variation in S. aureus strains that cause bovine mastitis.