RESUMO
This study included 1278 buffalos from 160 herds belong to 32 villages in the Middle Delta of Egypt randomly chosen to study factors which can influence infection with gastrointestinal parasites. Relationship between number of parasites, herd size, resources of water and season of the year was investigated. The results showed that Fasciola gigantica infection recorded the highest percentage [48.04%], followed by Neoascaris vitulorum and Eimeria spp. Percentage rates of parasitic infection [single, double or triple] in each animal were 62.80%, 29.43% and 7.77%, respectively. Infection rate tended to increase with herd size in most of the cases. Resource of water had highly significant effect on infection rate. The highest infection was recorded in summer and the lowest in spring or winter. The study also showed a negative and highly significant correlation between infection and number of parasites [0.99]. Herd size did not associate with infection, while temperature and relative humidity correlated significantly with infection rate [0.67 and 0.78, respectively]