ABSTRACT
The present study was aimed to examine the oxidative stress/antioxidant status in naturally infected ewes with gastrointestinal nematodes [GIN] after use of antioxidant vitamins such as vitamin A or E with antihelmintic treatment [ivermectin] .A total of 12 Barki ewes were chosen naturally infected with GIN, aged between [1.5 - 2.5] years, weighted between [35 -38 kg]. All ewes were treated with 2ml/50kg BW ivermectin. They were divided into three groups [n=4]. The first group was non-vitamin treated [the control group], the second group, was orally treated with vitamin A [0.5X10[5] IU/ewe/day] for four weeks, the third group was orally treated with vitamin E [75mg/ewe/day] also for four weeks. Fecal samples were collected from rectum of each ewe before the beginning of the trial and weekly after treatments. Degree of infestation was performed by fecal egg counting [FEC] and identified by fecal culture technique. Blood samples were collected from each ewe for biochemical analysis of serum lipid peroxide-Malondialdehyd [MDA], Nitricoxide [NO], total-antioxidant capacity [TAG] and glutathione-S-transferase [GST]. Ewes were weighed every two weeks till the end of the study. Four weeks post-treatment, MDA significantly [p <0.05] decreased in their levels in both vitamin treated groups in comparison to the control one, meanwhile NO showed no alterations in their levels in both treated groups in comparison to the control one all over the expermental period. Four weeks post treatment, there was significant [p <0.05] increase in the mean value of TAC in vitamin E treated group comparing with the other groups. While there were significant increase in GST level after the second and the fourth weeks in vitamin E treated group. It was concluded that vitamin E should be used at least 2 weeks with other antihelmintic protocols in order to obtain a more effective and earlier cure against GI parasites in infected sheep for improving their health and reproductive performance