Study on prevalence, clinical presentation, and associated bacterial pathogens of goat mastitis in Bauchi, Plateau, and Edo states, Nigeria

Aim: This study aimed to estimate the prevalence and clinical presentations of different forms of mastitis and mastitis-causing pathogens in lactating goats in Bauchi, Plateau, and Edo states, Nigeria. Materials and Methods: A total of 500 quarters from 250 lactating goats of Red Sokoto and West African Dwarf breeds during the lactation period were clinically examined. Clinical mastitis was detected by gross signs of udder infection during physical examination and abnormal milk, whereas subclinical mastitis (SCM) was recognized using California mastitis test. The bacterial pathogens were identified by morphology, hemolysis, gram staining, and biochemical tests such as catalase, oxidase, coagulase, reaction on sulfite, indole, and motile medium, and fermentation of sugars. Results: The overall prevalence of mastitis in goats was found to be 101 (40.4%), of which 8% (20/250) were clinical, and 32.4% (81/250) were SCM cases. The quarter level prevalence was 29.4% (145/493), comprising 5.9% (29/493) clinical and 23.2% (116/493) subclinical forms of mastitis. In addition, 1.4% (7/500) of teats were found to be blind on the clinical examination of the udder and teat. Several regional inflammatory reactions and abnormalities in milk were found in 69% and 100% of the cases, respectively. Moreover, some indications of generalized signs such as fever, reduction in appetite, increase in respiration, and pulse rate per minute were recorded in 100%, 75%, 85% and 80% of the cases, respectively. The predominant bacterial isolates recovered were Staphylococcus aureus (20.0%), followed by Escherichia coli (15.5%) and Streptococcus agalactiae (11.0%), and the least isolated microorganisms (≤6%) were bacteria of different species including Staphylococcus auricularis, Staphylococcus caprae, Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus hyicus, Staphylococcus xylosus, Staphylococcus lentus, Streptococcus dysgalactiae, Streptococcus pluranimalium, Streptococcus uberis, Streptococcus pneumoniae, Streptococcus ruminatorum, Streptococcus suis, Micrococcus luteus, Enterobacter cloacae, Proteus vulgaris, Klebsiella oxytoca, Klebsiella pneumoniae, Morganella morganii, Salmonella Typhimurium, Citrobacter freundii, Pseudomonas aeruginosa, Acinetobacter rudis, Acinetobacter haemolyticus, and Bacillus cereus. Conclusion: Mastitis continues to be recognized as one of the important health issues and leads to major economic losses to the dairy goats caused by many bacterial pathogens, and the effective measures need to be taken to control the disease