Molecular Identification of Key Mastitis causing Bacteria in Dairy Goats in Kenya

Abstract

Mastitis remains one of the most common diseases of the dairy goats, causing the biggest economic loss. Use of antimicrobial treatment is the generally recommended, but only after identifying the causal organisms. The use of PCR has emerged as the most accurate in microbial identification due to several advantages, including high sensitivity and specificity. The objective of this study was to apply PCR techniques in identification of the key mastitis causing bacteria, E. coli and Staph. aureus, isolated from a farm-survey carried out on goat milk in three goat keeping regions of Kenya, Coast, Rift Valley and Nyanza. Two gene specific primers for amplification of Staph. aureus sequence targeting the nuc gene, and E. coli sequence targeting the pic gene, were used as described in the materials and methods applied to 16 randomly selected pure bacteria cultures representing the three regions. In total six of the samples were positive for the pic gene, while five were positive for the nuc gene. Each of the genes was distributed to all the three regions. The positive identification of these genes indicates the potential for use of PCR in accurate goat mastitis diagnosis; it also indicates these mastitis causing pathogens are widespread in all dairy goat keeping regions of Kenya.