This study is done to clarify some adverse effects of gastrointestinal nematodes on immunological and biochemical status of draft horses and modulating by fenbendazol. Parasitological examination of 50 faecal samples revealed presence of gastrointestinal nematodes eggs in 38 (76%), horses distributed according to age {1- 4years 13 (34.21%), > 4-10 years 10 (26.32%)}, the type of infestations were single 12(31.58 %) or mixed 26 (68.42%). The single infestation were Strongylus spp < /em> 6 (15.79 %), Parascaris equorum, 4 (10.53 %), Oxyuris equorum 2(5.26%) while mixed infestation were Strongylus spp with Parascaris equorum 7 (18.42%), Parascaris equorum with Oxyuris equorum 5(13.16 %) and Strongylus spp with Parascaris equorum with Oxyuris equorum 14 (36.84%)}. The treatment with Fenbendazole revealed 100% reduction in egg count/gm on day 9 post treatment.
Gastrointestinal nematodes induce leukocytosis, neutrophilia, eosinophilia, monocytosis insignificant rise in lymphocytes, γ, β, total globulin beside insignificant decrease in α globulin and A/G ratio coupled with significant rise in AST, ALT, urea, creatinine and significant reduction in T.protein, albumin, ALP, trace elements (selenium, copper, iron and zinc) compared with healthy horse.
The present study revealed that fenbendazole had a non significant effect on total and differential leukocytic count and biochemical parameters in healthy draft horses.
In conclusion, the present study showed that gastrointestinal nematodes induce some adverse effects on immune status and biochemical parameters. Those effects were returned to the normal levels at 15 days post treatment with fenbendazole.