| Abstract: | The objective of the study was to estimate the losses associated with subclinical mastitis (SCM) in crossbred dairy cows in
the Central Highlands of Ethiopia. A split udder investigation was performed with 30 cows to determine production losses associated
with SCM. Each quarter of the study cows was examined using the California Mastitis Test (CMT) and quarter milk production
was measured over a period of 8 days. Production losses were determined for different CMT scores by comparing production of
quarters with CMT score 0 to quarters with CMT scores trace, 1, 2 and 3, respectively. Using data from a recently published
study, economic losses were determined for different farm sizes and production subsystems by multiplying the prevalence of
the respective CMT scores with the production losses associated with these CMT scores. Mean quarter milk production was 0.82
+ 0.40 kg per milking in the split udder trial. Milk production was reduced by 1.2%, 6.3%, and 33% in quarters with CMT scores
1+, 2+, and 3+, respectively. Using data from the published study, a quarter with SCM lost an average of 17.2% of its milk
production. Production losses associated with SCM were estimated at 5.6% for the Addis Ababa Milk Shed. Stratified losses
were highest (9.3%) in urban dairy farms (UDF) and small-scale farms (6.3%). The estimates of the financial losses ranged
from US$29.1 in dairy herds in secondary towns (DHIST) to US$66.6 in UDF. A total loss of US$38 was estimated for each cow
per lactation. Reducing mastitis in UDF (highest prevalence) to the level of DHIST (lowest prevalence) could reduce the loss
by US$35. As this does not include costs associated with treatment or culling of diseased cows, this figure probably underestimates
the possible benefits of control measures. |
