Detection of enterotoxins enconding genes, phenotypic and genotypic antimicrobial resistence, mecA and vanA and genic expression in bovine mastite cases by staphylococcus coagulase positive and negative isolates

Author(s)

Felipe de Freitas Guimarães

• Document type: Doctoral Thesis
• Press: Botucatu. 2016-08-12.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Medicina Veterinária e Zootecnia. Botucatu
• Defense date: 2015-02-05
• Advisor: Hélio Langoni

Abstract

A total of 300 isolates of bovine mastitis cases from several Brazilian dairy herds were studied, respectively: 150 CPS and 150 CNS strains. The isolates were analyzed to enterotoxins codifying genes by Polymerase Chain Reaction (PCR). Gene expression was evaluated by reverse transcription PCR (RT-PCR). The isolates were subjected to sensitivity profile correlated with the detection of mecA and vanA gene by PCR. Among the CNS the following species were identified: 48 (32%) S. warneri, 22(15%) S. epidermidis, 20(13%) S. hyicus, 10(7%) S. xylosus, 7(5%) S. haemolyticus, 6(4%) S. simulans, 6(4%) S. schleiferi subsp schleiferi, 6(4%) S. hominis, 5(3%) S. pasteuri, 4(2.7%) S. cohnii, 3(2%) S. saprophyticus subsp. saprophyticus 3(2%) S. chromogenes 3(2%) S. sciuri, 2(1%) S. saccharolyticus, 2(1%) S. lugdunensi, 1(0,7%) S. auriculares, 1(70%) S. saprophyticus subsp. bovis and 1(0.7%) S. capitis. Among the 150 CPS: 105 (70%) S. aureus, 21(14%), S. hyicus, 19(13%), S. intermedius and 5(3%) S. schleiferi subsp coagulans. The identification by phenotypic and genotypic tests showed a concordance of 96.7% in the CNS isolates, and 98.7% in the CPS. The codifying genes to enterotoxins production were detected to classical and enterotoxin-like in 175 (58%) out of 300 staphylococci isolates. These genes were detected significantly higher among the CNS (73%) in relation to CPS (44%), P<0.0001. In 109 CNS codifying genes to enterotoxins were detected in the following species: 37(33.9%) S. warneri, 17(15.6%) S. epidermidis, 16(14.7%) S. hyicus, 5(4.6%) S. xylosus, 5(4.6%) S. haemolyticus, 4(3.7%) S. simulans, 4(3.7%) S. schleiferi subsp schleiferi, 4(3.7%) S. homini, 4(3.7%) S. pasteuri, 3(2.7%) S. saprophyticus subsp. saprophyticus, 3(2.7%) S. cohnii, 3(2.7%) S. chromogenes, 2(1.8%) S. sciuri, 1(0.9%) S. lugdunensis and 1(0.9%) S. capitis. Among the 66 CPS, the enterotoxin genes were observed in the following species: 48(73 %) S. aureus, 10(15%) S. hyicus, ... (AU)

• FAPESP's process: 11/21142-2 - Research of encoding genes of staphylococcal enterotoxins and vancomycin resistance gene vanA: detection of genic expression in Staphylococcus coagulase positive and negative in bovine mastitis
• Grantee: Felipe de Freitas Guimarães
• Support Opportunities: Scholarships in Brazil - Doctorate