Abstract

A cross-sectional study was conducted to determine the prevalence of mastitis in bovines and to, isolate and identify the major bacterial pathogens of lactating cows in six selected woredas of Bench Maji Zone of Southwestern Ethiopia from June 2017-October 2017. Three hundred eighty four lactating cows were examined for mastitis by combination of udder physical examination, California Mastitis Test and subsequent bacteriological isolation. During the study period, 116 (30.21%) cows had mastitis, of which 35 (30.17%) and 81(69.83%) showed clinical and subclinical mastitis, respectively. The prevalence rates of mastitis in cross breed and local breed cattle were found to be 71.43 and 28.65%, respectively. Based on parity, higher prevalence (45.45%) was recorded in cows which had greater than 5 parturitions and the lower prevalence (13.04%) was recorded in cows with 1-2 parturitions. Based on lactation stage, the prevalence was (45%) in late stage, followed by middle stage (36.60%) and early stage of lactation (13.85%). The prevalence rates of mastitis based on different age groups of lactating cows were found to be 48.78 , 30.54 and 18.52% in cows of greater than 8 years old, 4-8 years old and in cows less than 4 years old, respectively. Except parity, the other associated risk factors (breed, lactation stage and age group) had significant association (P<0.05) with the prevalence of mastitis in the study animals. Upon subsequent bacterial culturing, the quarter milk samples yielded three types of bacteria. Staphylococcus aureus (59.26%), Streptococcus agalactiae (38.27%) and Escherchia coli (2.47%) were the major isolates. In conclusion, the overall prevalence of mastitis in lactating cow of the study area was high and this suggests the need of improved hygienic practices and applies different methods for prevention and strategic control of the disease.

Key words: Bacteria, cows, Ethiopia, mastitis, prevalence.