Mastite bacteriana em animais domésticos: principais agentes etiológicos e mecanismos patogênicos

• DOI: https://doi.org/10.22533/at.ed.659112610026

• Palavras-chave: Lactação, Saúde Única, Zoonoses, Biofilme, Bactérias

• Keywords: Lactation, One Health, Zoonoses, Biofilm, Bacteria.

• Abstract: Mastitis is an inflammation of the mammary gland of high relevance in veterinary medicine due to the sanitary and economic impacts it causes on animal production. The disease promotes physicochemical and organoleptic changes in milk, in addition to compromising the mammary parenchyma, resulting in reduced productivity, milk discard, increased treatment costs, and damage to the quality of dairy products. Mastitis has a multifactorial etiology, involving interaction between the host, the environment, and different infectious agents. Among the main microorganisms related to the disease are bacteria of the genera Staphylococcus and Streptococcus, considered the most frequently isolated agents in clinical and subclinical cases. Species such as Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, and Streptococcus uberis have high epidemiological importance due to their ability to spread within the herd and their antimicrobial resistance. Other bacterial groups are also relevant, including Corynebacterium spp., Nocardia spp., Trueperella pyogenes, Mycoplasma spp., and environmental enterobacteria such as Escherichia coli and Klebsiella pneumoniae, frequently associated with severe cases of clinical mastitis. Furthermore, opportunistic agents such as Pasteurella multocida, Mannheimia haemolytica, and anaerobic bacteria, especially Clostridium perfringens, can cause necrotizing and severe forms of the disease. Pathogenesis involves bacterial virulence factors, host immunity, and inadequate management and hygiene conditions. Therefore, microbiological diagnosis, sanitary monitoring, and the adoption of appropriate preventive measures are fundamental to reducing the spread of etiological agents and minimizing the economic losses associated with mastitis in domestic animals.