FREIRE, D. H. F.; http://lattes.cnpq.br/0602208322622722; FREIRE, Daneelly Henrique Ferreira.
Resumo:
The main disease that affects the goat dairy herd is intramammary infections, which
usually have coagulase negative (SCN) and positive (SCP) Staphylococcus etiology. In this
north, the present study aimed at the genotypic and phenotypic characterization of
Staphylococcus isolated from subclinical goat mastitis as well as to characterize the virulence
factors associated with these bacteria. 400 goat milk samples were collected from 25 farms
distributed in five municipalities in Paraíba that have a dairy goat herd, resulting in 105
isolations characteristic of Staphylococcus spp., The species were identified by Malditof.
The
genotyping of the isolates was performed using REPPCR,
using the primer RW3A, the
images were processed by the software BioNumerics ©, the degree of similarity was
established using the Jaccard coefficient (5%). Individual PCRs were carried out aiming to
identify sea, seb, sec, sed, see, sec, seh and sei enterotoxin genes and blaZ and mecA
resistance genes, hemolytic samples were tested for IcaD. The reactions had a final volume of
50μL, PCR SuperMix (Invitrogen, Brazil) was used with 0.4 mM of each primer. The
determination of phenotypic resistance was performed using the disk diffusion technique. The
following discs were used: Cefoxitin 30μg, Oxacillin 1μg, Gentamicin 10μg, Erythromycin
15μg, Tetracycline 30μg, Ciprofloxacin 5μg, Sulfa / Trimetropim 25μg, Clindamycin 2μg,
Penicillin 10U, Clorafenicol 30μg. Fisher's exact test (p >0,05) was performed to buy species
and resistance. A total of 15 species of Staphylococcus were identified in the five
municipalities evaluated. The main species causing subclinical mastitis were S. epidermidis
(36%), S. caprae (24%), S. lugdunensis (13%), S. simulans (7%) and S. xylosus (4%). The
municipality that presented the greatest diversity of species was Prata. REPPCR
identified 28
profiles with 100% similarity, it was observed that bacterial species genotypically clones
(100% similarity) are responsible for subclinical mastitis in different cities. The presence of
enterotoxin genes was identified in eight Staphylococcus (7.6%), of these three presented sec
and five seh, three samples presented the sec and seh gene simultaneously. High resistance
rates have been identified for Penicillin (40%), Sufa / Trimetropim (33%) and Tetracycline
(25.5%). Three strains of SCN showed phenotypic resistance to oxacillin characterizing
MRSCN and a strain of S. aureus (MRSA). All samples were sensitive to Gentamicin. In the
investigation of the genotypic resistance profile, positive isolates for the blaZ (26.6%) and
mecA (1.1%) genes were revealed. Hemolytic isolates tested for icaD (50%), biofilm
production capacity was observed. Considering the characterization of the main bacterial
agents that cause mastitis and its virulence and resistance factors, they guide the role of the
goat food chain as reservoirs of pathogens that generate public health risks, the high rates of
resistance and identification of biofilm producing strains indicate flaws in therapeutic
practices.