Effect of copper oxide wire particles compared to copper sulphate on Haemonchus contortus infection in lambs
Infection with gastrointestinal nematode (GIN) parasites, particularly Haemonchus contortus, a blood-feeder, is the most important constraint to profitable small ruminant production in the southeastern US and worldwide. Weanlings are especially susceptible to infection during their first grazing season. Infection with H. contortus can rapidly lead to lost production and even death. Over use of anthelmintics (dewormers) has resulted in high levels of dewormer resistance in GIN throughout the southeast and other regions where H. contortus is a problem. The problem has become so severe that it is threatening viability of small-scale and limited-resource small ruminant farm operations in this region despite continued high demand for sheep and goat products. A more sustainable approach to parasite control involves integrating targeted, limited use of anthelmintics with non-chemical alternative control methods that reduce GIN numbers in the host animal and lower pasture contamination with eggs and larvae. Copper oxide wire particles (COWP) have been shown to reduce infection in sheep and goats. Preliminary evidence has shown that copper sulphate (CS), as a drench, may also be useful. Since copper can be toxic to sheep, the question of which has the least impact on toxicity has become an issue. In the proposed study, COWP and CS will be evaluated for affect on naturally acquired H. contortus infection and potential toxicity. Results will be disseminated to scientific and producer groups via producer workshops, the Southern Consortium for Small Ruminant Parasite Control web page (SCSRPC.org), and various scientific and extension publications.
1) Determine the effect of COWP compared to CS on H. contortus infection in grazing lambs and 2) Determine the liver copper accumulation of COWP compared to CS in grazing lambs.
The originally proposed project was intended to be conducted in summer 2010. Due to unexpected circumstances, the study was not possible; therefore, a preliminary study (Study 1) was done to establish short term efficacy of COWP and CuSO4. The proposed longer term comparison study (Study 2) will be conducted during the summer 2011. For Study 1, 21 lambs were randomly allocated to 3 treatment groups [COWP (2 g/hd), CuSO4 (1% solution drench, 35 ml/22.7 kg) and a control (CONT). Each group had 7 lambs. Fecal egg count (FEC) was conducted on day 0, 7 and 14 after treatment. FEC was log transformed and a repeated measures ANOVA over time was conducted. Means were adjusted for the variables in the model.
Impacts and Contributions/Outcomes
For Study 1, there was no significant difference between groups (p>0.05) on day 0. On days 7 and 14, there was no difference (p>0.05) between CONT, and CuSO4 groups, and the COWP group was significantly (p<0.05) lower than the CONT group. Results indicated that COWP was effective in reducing infection, and CuSO4 was not. Study 2 is pending.
Louisiana State University
Department of Pathobiological Sciences
School of Veterinary Medicine
Baton Rouge, LA 70803
Office Phone: 2255789658