Survey of mastitis in dairy herds in the Ethiopian central highlands

Prevalence of mastitis amongst dairy herds (n=725) and cows (n=2681) of Addis Ababa milk shed was investigated. California Mastitis Test (CMT) was conducted on milk samples from individual quarters. Of 10,908 quarters examined, prevalence of clinical mastitis (SCM), nonfunctional or blocked quarters (NFBQ) and subclinical mastitis (SCM) were 1.2 percent, 3.8 percent and 38.9 percent, respectively. Subclinical mastitis had highest relative occurrence (88.1 percent). Prevalence of quarter SCM was over 40 percent in Urban (n=5402) and Peri-urban Dairy (n=2454), and 25.1 percent in Dairy Herds Intra-Urban (n=5402) and Peri-urban Dairy (n=2454) and 25.1 percent Dairy Herds Intra-Urban of the Secondary Towns (n=2334) and the same increased with the herd size. On cow basis, prevalence of SCM was 18.7 percent and was higher in crossbred (n=2287; 21.3 percent) than with zebu (n=397; 4.3 percent). Significantly more SCM occurred in parity two and above (n=1978; 20.6 percent) than those in first parity (n=699; 13.2 percent) but this did not increase with lactation number. Over 87 percent of CMT reactions were scores distributed between Score 1 to 3, and were suggestive of infection. It was concluded that SCM is highly and widely prevalent. As it is economically damaging, the need to establish diagnostic facility to be able to early detect and screen large number of samples is emphasized and further work on identification of causative agents is recommended.