Abstract:
402 Proc. Aust. Soc. Anim. Prod. Vol. 17 TOPICALLY APPLIED ANTHELMINTIC FOR MERINOS A.J. GIBBON AND S.L. BURMAN Levamisole (LVS) is a highly effective, widely used anthelmintic for the control of gastro-intestinal nematodes and lungworms of sheep. The compound is readily soluble and is ideally suited for formulating into dermally absorbed solutions. Several formulations are already in use with cattle. Preliminary chemical and statistical analysis of serum LVS in treated sheep showed that a dermal dose rate of 20mg LVS per was necessary to achieve bio-equivalence with an oral dose of 6.0mg LVS per kg. Variability of results in British breeds and led to the recommendation for treatment of Merino sheep only. levels obtained kg live weight 'Nilverm', at cross bred sheep Efficacy of the pour-on formulation which used acetate ester solvents was confirmed in worm-infested Merino sheep treated topically with 20mg LW per kg. The treatments were applied as either a 'spot' at skin level on woolly sheep, or as a narrow 'stripe' on shorn sheep with less than 50mm of ~7001. Treatments were applied along the backline of the sheep using a dose volume of lml per 5kg liveweight. Table 1. Geometric mean worm counts in control sheep and efficacy (Z) of treatments Analysis of variance showed all treatments caused a statistically significant reduction in worm burdens,but there were no statistically significant differences between treatments. In summary, development of the pour-on formulation has shown that when applied topically to Merino sheep at 20mg LVS/kg, the treatment was efficaceous regardless of fleece length and is bioequivalent to orally administered LVS products. Coopers Animal Health Aust. Ltd, The Northern Road, Bringelly, N.S.W. 2171