Fenbendazole efficacy in lambs: a comparison of oral dosing and feed block additive modes of administration
Twenty-four, 3-month old West African Dwarf (WAD) lambs were divided into 3 groups of 8 each. Each group was given free access to a common pasture by day, but housed separately in concrete-floored and netted pens provided with varied but equal supplements by night. Two of the groups were treated with 2.5% Fenbendazole suspension at a dose rate of 10mg/kg body weight administered orally once a month for 3 consecutive months for one group, dissolved in molasses mixed with Brewer's grains in 5 divided daily doses per month for 3 consecutive months for the second group, while the third 3rd group was left as untreated control. The mean haematocrit values, mean percentage egg reduction and mean liveweight gains were higher at the end of the trial for the single monthly dosed group than for the untreated control group, while the same measurements were insignificantly different (P>0.05) for the two treated groups. Significant appreciation in the mean haemotocrit values, mean percentage egg reduction and mean liveweight gains were proofs of the effectiveness of treatment and molasses supplementation, while the insignificance of the difference of the same measurements in the two treated groups implied equal efficacy of the two different schedules of administration. The in-feed scheme was easier and convenient for use on weak and pregnant ewes that could abort on rough handling.
Keywords: Fenbendazole efficacy, lambs, feed-block additive