Comparison phenotypic and genotypic identification of Staphylococcus species isolated from bovine mastitis

Abstract

In addition to Staphylococcus aureus nowadays other coagulase-positive staphylococci (CoPS) and coagulase-negative staphylococci (CoNS), earlier considered of minor importance, are now accepted as relevant pathogens for humans and animals. The involvement of these microorganisms in bovine mastitis etiology and the possibility their transmission through milk to humans justify the requirement of developing reliable methods for identification of the most frequent species among them. The purpose of this study was to compare the phenotypic techniques with the genotypic method carried out by sequencing of the rpoB gene in identification of several species of the genus Staphylococcus isolated from bovine mastitis. A total of 300 staphylococci isolates of bovine mastitis cases from several Brazilian dairy herds were studied by phenotypic and genotypic techniques, respectively: 150 CoPS and 150 CoNS strains. A total of 18 CoNS different species and 4 CoPS species were identified. Among the CoNS the following species were recognized: 48 (32%) Staphylococcus 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. auricularis, 1(70%) S. saprophyticus subsp. bovis, 1(0.7%) S. capitis. And among the 150 CoPS were identified respectively: 105 (70%) S. aureus, 21(14%), S. hyicus, 19(13%) S. intermedius e 5(3%) S. schleiferi subsp coagulans. Considering the 150 CoNS isolates, the identifications performed by phenotypic and genotypic tests presented 96.7% of concordance, kappa coefficient of agreement = 0.933, SE (standard error) of kappa=0.021 (95% confidence interval: 0.893 to 0.974), Pearson's correlation coefficient (r) = 0.9977, (confidence interval 95%: 0.9938 a 0.9992) and in relation to 150 CPS isolates it was detected an agreement of 98.7%, kappa = 0.960, SE of kappa = 0.016, (95% confidence interval: 0.929 to 0.992) Pearson's correlation coefficient (r) = 0.9994 (95% confidence interval: 0.9681 to 1.0000). The verified agreement strength between the identification methods can be considered as excellent. These results assure that according to laboratory resources any of them will be suitable to perform the staphylococci identification. Considerando-se os 150 SCN isolados, as identificações realizadas por testes fenotípicos e genotípicos apresentaram 96,7% de concordância, coeficiente de concordância kappa = 0,933, SE (erro padrão) de kappa = 0,021 (95% intervalo de confiança: 0,893-0,974), coeficiente de correlação de Pearson (r) = 0,9977, (intervalo de confiança de 95%: 0,9938 a 0,9992) e em relação a 150 SCP isolados foi observado uma concordância de 98,7%, kappa = 0,960, sE de kappa = 0,016, (95% de intervalo de confiança: 0,929 a 0,992) coeficiente de correlação de Pearson (r) = 0,9994 (95% intervalo de confiança: 0,9681-1,0000). A...

Etiology and in vitro antimicrobial susceptibility profile of strains isolated from bovine mastitis in dairy herds from the midwest region of Santa Catarina state, Brazil

“…In Brazil, others authors found similar frequencies, ranging from 8.3% to 57.8% (COSTA KREWER et al, 2015;MARTINS et al, 2010;MELLO et al, 2012;LAFFRANCHI et al, 2001;OLIVEIRA et al, 2011). Besides S. aureus, other species of Staphylococcus that were earlier considered of minor importance are now accepted as relevant human and animal pathogens (GUIMARÃES et al, 2016). In the present study, four species of coagulasenegative staphylococci were identified: S. haemolyticus, S. epidermidis, S. pasteuri and S. xylosus, which were previously detected in mastitis milk samples (FREY et al, 2013;GUIMARÃES et al, 2016;SOARES et al, 2012;XU et al, 2015).…”

“…Besides S. aureus, other species of Staphylococcus that were earlier considered of minor importance are now accepted as relevant human and animal pathogens (GUIMARÃES et al, 2016). In the present study, four species of coagulasenegative staphylococci were identified: S. haemolyticus, S. epidermidis, S. pasteuri and S. xylosus, which were previously detected in mastitis milk samples (FREY et al, 2013;GUIMARÃES et al, 2016;SOARES et al, 2012;XU et al, 2015). The results obtained reinforce the importance of these pathogens as mastitis causing agents in dairy herds of the Midwest region of Santa Catarina State, having a direct implication for infection control measures, since the correct identification of the etiological agent is fundamental to establishing appropriate prevention and control measures (HENNEKINNE et al, 2010).…”

Identification of Staphylococcus species isolated from preputium of Aceh cattle based on 16S rRNA gene sequences analysis

“…[32] reported that 3.8% of sea fish were positive for S. pasteuri . Another investigation in Brazilian dairy herds using milk samples from bovine mastitis cases reported the incidence of S. pasteuri as 3.3% [10]. According to epidemiological analysis, Savini et al .…”

“…There are numerous studies regarding Staphylococcus pasteuri as a potential pathogen found in various environmental conditions. The spread of S. pasteuri in plant food environments and animals has been reported by several authors and their studies described that vegetables [7,8], and leafy vegetables, including perilla leaf, chicory, and lettuce from local markets in South Korea [8], pig farms in the Netherlands [9], and bovine mastitis from Brazilian dairy herds [10] were contaminated or caused by S. pasteuri . In our previous investigation of cellulolytic Enterobacte r [11], and cellulolytic Bacillu s [12], both bacteria were found in the rumen of Aceh cattle.…”

Genetic relationship of Staphylococcus aureus isolated from humans, animals, environment, and Dangke products in dairy farms of South Sulawesi Province, Indonesia

“…Identifying S. aureus can use phenotypic and genotypic methods. Phenotypic methods include the culture method, followed by Gram staining, fermentation, catalase, and coagulase [10,11]. Genotypic methods include comparative methods based on standard band electrophoresis, genome characterization, and sequencing methods.…”