Studies on Johne's disease in Egyptian cattle.

Johne's disease (JD) or paratuberculosis is a serious problem of cattle industry worldwide. For a long period of time, Egypt was considered to be free of JD. In the present study, 2150 Egyptian cattle were examined clinically for JD. Among these, samples from 160 cows were investigated for the presence of Mycobacterium avium ssp. paratuberculosis using various laboratory methods including direct microscopic examination, faecal culture and polymerase chain reaction (PCR). According to the data obtained by the culture method, positive results could be observed for 75 cows from three of five investigated districts in Egypt. Comparably investigated samples from 40 cows of one known positive flock from Hesse, Germany yielded positive reactions for 20 cows. The present study is the first description of JD in Egypt.