Abstract:
Mastitis is a disease of major economic importance in the dairy industry world wide. The objectives of this study were; to estimate the incidence of mastitis and mastitis treatment failure with the potential risk factors for the unsuccessful treatment of bovine clinical mastitis in the study area. A prospective Cohort study was conducted from October 2018 to June 2019 in Dire Dawa and Harar intensive dairy farms. In the study period, 98 dairy cows with an incident clinical mastitis were enrolled in the study. Milk samples were collected from each cows and there exposure status to fungal and bacterial pathogen were assured following a standard laboratory protocol. Cows were grouped based on potential pathogen exposure and the interventions made to the cows were recorded on a daily bases. Follow up was made for 15 days to determine the clinical cure of the cows (treatment failure or success). Collected data were entered and managed by STATA version 14. Descriptive statistics for the incidence of mastitis in respective farms and binary regression for generalized linear model for relative risk was run to estimate the strength of association between the exposure factor and the treatment outcome. P-value <0.05 were considered statistically significant. The overall incidence of mastitis in dairy cattle at the farm-level was 21.10% (17.40-25.10), and the incidence rate of mastitis per cow-days at risk was 0.00237. Among the potential intrinsic and extrinsic risk factors; The relative risk for breed, age, parity, lactation stage were 0.77, 1.38, 1.48 and 1.60 respectively,were found significantly associated (P<0.05) with bovine clinical mastitis treatment failure. In the meantime, cows with fungi pathogens were 2.7 times(RR=2.7; 95%CI=1.79-4.06) more likely developing mastitis treatment failure than those cows without the exposure. Dairy cows with bacterial exposure were 1.40 times (RR=1.40; 95%CI=1.12-1.77) more likely encountered mastitis treatment failure than their counterpart. As well, dairy cows with mixed fungal and bacterial exposure were 1.32 times (RR=1.32; 95%CI=1.02-1.69) more likely to face mastitis treatment failure than those without the mixed infection. In this study different fungal and bacterial pathogens isolated were; 18.36% A.fumigates, 27.50 % C.alibicans, 16.30% Staphylococcus aueres. Thus, fungus was one of the predictor agents of mastitis treatment failure in dairy cattle in the study area.
