Using COWPs to Improve Dewormer Efficacy

USDA ARS (Boonville, Arkansas) conducted an experiment in weaned lambs to determine the effect of treatment with two sources of copper oxide wire particles (COWP), albendazole (Valbazen®), or a combination of albendazole and COWP. There were five treatment groups:

1.  Control (no treatment)
2.  COWP (Copasture®)

3.  COWP (Ultracruz™)
4.  COWP + albendazole

5.  Albendazole (Valbazen®)

A 2 g dose of COWP was used, but only 1 g is normally recommended for lambs. Albendazole (Valbazen®) was given at double the labeled dose at 15 mg/kg of body weight (3 ml/50 lbs.). There were between 10 and 23 lambs per treatment. The flock was determined to have resistance to benzimidazoles (same class of dewormer as albendazole) by the Drenchrite® test. The population of worms was mixed (H. contortus, Trichostrongylus spp., Cooperia spp., Oesophagostomum spp.).

There was an increase in fecal egg counts in the untreated lambs and a reduction in all other groups. The greatest reduction occurred in lambs treated with both COWP and albendazole (99.1%). The reduction with COWP alone was 12% and 58%, respectively, using Copasure® and Ultracruz™.  While numerically different, there was no statisical difference between the different forms of COWP. Albendazole alone reduced fecal egg counts by 20 percent.  Similarly, albendazole alone was not statistically different from COWP alone.

Read full article