Bovine mastitis: prevalence and antimicrobial susceptibility profile and detection of genes associated with biofilm formation in Staphylococcus aureus

Abstract

Brazil currently ranks as one of the world leaders in food production and exportation. This scenario encourages the development of animal and plant health programs to ensure the production of safe food, helping the country to become an international provider of food for excellence. However, some health problems in dairy production, such as mastitis, have garnered increasing concern. This study aimed to estimate the prevalence of bovine mastitis in select properties located in the western Santa Catarina region, to assess the susceptibility profile to antimicrobial agents used for treatment and to check for the presence of genes (icaA and icaD) associated with biofilm formation in Staphylococcus aureus. In 148 milk samples collected, 72.97% had bacterial growth (n = 108). Among the isolated microorganisms, 21.62% (n = 32) were classified as Staphylococcus aureus, 18.91% (n = 28) as Staphylococcus sp. coagulase negative, 7.43% (n = 11) as Corynebacterium sp., 6.76% (n = 10) as Staphylococcus sp. coagulase positive, 5.41% (n = 8) as Nocardia sp. and 12.83% (n = 19) classified in different bacterial genera. Among the isolates submitted for antimicrobial susceptibility testing, it was observed that 8.95% (n = 6/67) had resistance to amoxicillin, 8.04% (n = 7/87) to ampicillin, 5.88% (n = 5/85) to cephalothin, 3.40% (n = 3/88) to ceftiofur and enrofloxacin, 20.45% (n = 18/88) to streptomycin, 17.04% (n = 15/88) to gentamicin and lincomycin, 31.81% (n = 28/88) to neomycin, 14.94% (n = 13/87) to penicillin and 25% (n = 22/88) to tetracycline. Staphylococcus sp. coagulase negative isolates showed higher multidrug resistance when compared to those of S. aureus and Staphylococcus sp. coagulase positive. Thirty-one strains of S. aureus isolates were genotypically tested by polymerase chain reaction (PCR), yielding a positive result for the icaA gene in 83.87% of the samples, 80.64% positive for icaD and 74.19% of these showed both genes. The results reinforce the importance of controlling this disease by adopting strict hygiene protocols and disinfection of equipment used for milking and the prescription of appropriate therapies to clinical and subclinical cases of mastitis, as well as evaluating not only the susceptibility profile of isolates but also the biofilm formation capacity. ResumoO Brasil situa-se hoje como um dos líderes mundiais em produção e exportação de alimentos. Este cenário incita a elaboração de programas de sanidade animal e vegetal que garantam a produção de alimentos seguros, contribuindo para que o país se torne um fornecedor internacional de alimentos por excelência. Entretanto, alguns problemas sanitários na produção leiteira, como a mastite, têm acarretado crescentes preocupações. O presente estudo teve como objetivo estimar a prevalência de mastite bovina em algumas propriedades localizadas na região Oeste de Santa Catarina, avaliar o perfil de suscetibilidade aos antimicrobianos empregados para tratamento e verificar a presença de genes (icaA e icaD) associados à formação de biofilmes em ...

Identification and antimicrobial suceptibility profile of bacteria causing bovine mastitis from dairy farms in Pelotas, Rio Grande do Sul

“…Many chronic infections caused by this pathogen are related to the biofilm formation; this feature hinders the action of macrophages, and also provides resistance to several antibiotics and promotes the residual persistence of these in the environment (Boyen et al, 2009). In the study conducted by Casanova et al (2016), thirty-one S. aureus strains isolated from mastitis milk were genotypically tested by the polymerase chain reaction (PCR), giving positive for the icaA gene in 83.87% of the samples, 80.64% were positive for the icaD gene and 74.19% showed both genes, associated with biofilm formation in S. aureus.…”

Risk factors associated with the occurrence of multiresistant Staphylococcus spp. isolated from bovine subclinical mastitis in northern Brazil

“…Conversely, the percentage of resistance to clindamycin was higher among the coagulase-negative strains compared to the positive strains. Although S. aureus is among the most prevalent and pathogenic species (Aslanta & Demir, 2016), isolates from the CNS lineage may show greater resistance to the total number of antimicrobial classes, as well as a high profile of resistance to multiple drugs (Schmidt et al, 2015;Casanova et al, 2016). In this study, the multidrug resistance profile was also higher among the CNS (17/19), with S. chromogenes being the predominant species (12/19).…”

“…Freitas et al (2018) concluded that multidrug resistance to antimicrobials occurs due to the extreme, empirical, or inadequate use of these drugs in the treatment and/or prophylaxis of diseases in bovine mammary glands. However, Casanova et al (2016) suggested that resistance to multiple drugs in treatment may be associated with the persistence of agents in the herd, leading to cases of chronic infection and predisposing to further infection.…”

“…Bovine mastitis is an inflammatory reaction of the mammary gland (Moritz & Moritz, 2016), usually of an infectious nature. Bacteria are the main etiological agents for bovine mastitis (Casanova et al, 2016), and it is described by several authors as one of the most important diseases of dairy herds.…”

“…Staphylococcus has been identified in several studies as one of the main pathogens that cause mastitis (Aslanta & Demir, 2016;Casanova et al, 2016). This genus is important not only because of its ubiquitous nature, but also because of its multiresistance to antibiotics used in intervention protocols, making mastitis a disease of public health concern (Ganda, Bisinotto, Decter, & Bicalho, 2016).…”