COWP: "hit and miss" in NY State
As part of a Northeast SARE grant, thirteen on-farm trials studying the effect of COWP (copper oxide wire particle) dosing on goats and sheep were conducted from 2013 through 2017 by Cornell University.
Fecal samples and FAMACHA© scores were taken at the beginning of each trial and approximately every 4 weeks for 4 to 9 weeks. Kids and lambs were weighed at the beginning and end of each trial, and at weaning (if weaned during the trial). Total Strongyle eggs per gram were determined by McMaster procedures for each individual fecal sample. A lectin binding stain using a peanut agglutinin (PNA) was used to calculate the percentage of Haemonchus contortus (barber pole worm) eggs.
The effectiveness of COWP to reduce H. contortus was variable among the farms in the study. The results of the majority of the studies did not support the hypothesis that COWP use is as effective as chemical anthelmintics to control H. contortus. Dosing with COWP was very effective for 3 years in a row at one farm, showed significant short term effects at some farms, and was of no value in reducing worm loads on other farms.
Further investigation is warranted to explain the farm-to-farm variability. However, in cases where COWP was effective, low dosages often preformed as effectively as higher dosages.
Source: Final Report for NE SARE Grant