T-Cell Responses to Mycobacterium Avium Ppd Antigens in Gastro-Intestinal Helminth Co-Infected Chickens in Central Ethiopia

A cross-sectional study as conducted on extensively reared chickens of three selected agro-climatic zones in Central Ethiopia to examine the predisposing effect of gastro-intestinal helminthes to intestinal Mycobacterium avium hen it Occurs as co-infection. This was done through a Lymphocyte Stimulation Test (LST) using avian PPD on peripheral blood mononuclear cells obtained from the blood of chickens and gross examination of digestive tract for the presence of helminth parasites, Data were analyzed using the statistical softwares SAS (1994) and Intercooled STATA version 6. Fourteen (14.7%) Out of the 9 examined chickens were positive in in vitro LST showing Stimulation index (SI) greater than or equal to 2. There was a significant (chi(2) = 9.93, P < 0.01) difference in prevalence of M. avium by altitude: highest in chickens from lowland (27.8%) areas, followed by 13.3% in chickens from mid altitude and none was reacted to LST from highland region. A significant relationship (chi(2) = 9.58, P < 0.01) in cestode co-infection with If. avium as found. There was no significant (chi(2) = 1.66, P > 0.05) relationship in nematode co-infection with M. avium.