Preliminary study on Antibacterial activity of plants used for treatment of Bovine mastitis in Southern Tigray

Ethiopia is endowed with a huge potential of medicinal plants that provide a wide contribution to the treatment of human and livestock aliments. A cross sectional study was conducted in selected districts of southern zone of Tigray region with objectives of identifying plants used for treatment of bovine mastitis and determining the antimicrobial efficacy of common medicinal plant extracts against major drug resistant bacterial isolates (Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli). Respondents were selected using a purposive sampling technique. A comprehensive survey using a semi- structured questionnaire was used to collect relevant information on the traditional medicine practices of the local communities. Seventeen plants used for treatment of bovine mastitis were identified. From those, ten common medicinal plants were extracted to conduct in vitro antimicrobial efficacy. The roots, leaves and seeds of medicinal plants were shade dried, ground to powders and the crude extracts were prepared using ethanol (99.8%). The results showed that the highest percentage yield was recorded for extract of Solanum incanum (95.8%) and the lowest yield was observed for extract of Cadia purpurea (46%). The crude extract of Heliotropium cinerascens had highest zone of inhibition (26±1.15 mm) against E. coli, the crude extract of Cadia purpurea had shown antimicrobial activity against S. agalactia with inhibition zone of 25.0 ±0. 577 mm and crude extract of Solanum incanum and Cadia purpurea had highest zone of inhibition (22.0±0.577 and 22.0±1.154 respectively). Results of this study suggest that the tested plants had antibacterial activity, which necessitates further studies in identification of phytochemical(s) for development of new pharmaceutical agent.