Risk factors identified associated with tuberculosis in cattle at 11 livestock experiment stations of Punjab Pakistan

The study was carried out in cattle kept at 11 livestock experiment stations of Punjab by using single comparative cervical intradermal tuberculin (SCCIT) test. Sahiwal was the main breed kept at these farms. Sixty three percent of animals were between four and 10 years of age. Seventy-six percent of animals weighed between 300 and 400 kg and 66% produced 5–10 l of milk/day. Animals other than cattle were present at about 64% of these farms. The positive SCCIT test was recorded in 7.6% of animals at the 11 farms. However, the prevalence of tuberculosis varied from 2.0% to 19.3% at these farms. Bivariate frequency analysis showed that the chances of a positive SCCIT test were higher in older animals, in cattle with higher number of calving and those produced up to 1800 l of milk. However, the chances of positive SCCIT test decreases with further increase in milk production. Results of bivariate and/or multivariate logistic regression analysis after controlling for the farm showed a significant association of age of cattle, numbers of calving, total milk produced, per day milk, lactation length, presence of sheep at the farm and total numbers of animals at the farm with a positive SCCIT test. It can be concluded from the study that herd prevalence of tuberculosis was 100%, while animal prevalence was about 8% at these farms. The stronger risk factors identified by logistic analysis were the age of cattle, numbers of calving, total milk produced and lactation length, while the presence of sheep at the farm has protective effect.