The main propose of this study was to investigate the effect of single dose administration of different levels of wattle tannin drenches on gastrointestinal nematodes faecal egg counts in Moghani sheep. Approximately 250 free grazing Moghani ewes were monitored for finding gastrointestinal nematode infected animals usigng Mc master technique and among them, 20 infected ewes (averaging 7-12 months by mean live body weight (LBW): 33±2 kg) were selected randomly and divided into 4 treatment groups. One of the groups was control group and received only tap water as placebo and the rest three groups were drenched single dose of 1, 1.5 and 2 gr WT/kg LBW respectively. Subsequently, faecal samples were taken 6, 12, 24 and 48 hours after drenching from each group and FECs were examined and recorded. Data were analyzed as a complete randomized design for repeated measurements using SAS (9.1). Results shown Treatment with 1.5 gr WT/kg body weight could cause significant reduction in FEC, from 24 hours after drenching so that its effect remained constant up to end of the study, whereas administration of 2 gr WT/kg body weight demonstrated its efficacy from 12 hours after drenching and reached to the maximum efficacy after 24 hours and then FEC levels remained constant up to the end (P< 0.05). Administration of 1 gr WT/kg LBW had no significant effect on FEC after 6, 12, 24 and 48 hours after drenching (P> 0.05).
