Copper oxide wire particles to control H. contortus on sheep and goat farms with a range of grazing practices

Copper oxide wire particles to control H. contortus on sheep and goat farms with a range of grazing practices

Summary

Copper oxide wire particles (COWP) are an alternative to chemical anthelmintics. COWP have effectively reduced infection of barber pole worm (H. contortus) in the Southeast US, but it is not clear how safe and effective COWP are in the Northeast. The objective of this project is to educate farmers about how to integrate limited anthelmintic use with other strategies for controlling internal parasites and determine effectiveness and risks of incorporating different dosages of COWP into parasite management systems for Northeast farms.

COWP on-farm studies were conducted in cooperation with one goat dairy and three sheep farms during the 2013 grazing season using funding from other sources. Data from these studies were analyzed this fall to help define further COWP research. This information will help to design the 2014 NESARE-funded on-farm studies. There were 320 participants (some repeats) in the nine FAMACHA Certification workshops, four “What’s new in sheep and goat parasite management” workshops and the on-farm field day led by our sheep and goat parasite team from Oct 1, 2012 to Dec 5, 2013. At least five veterinarians, 23 veterinary and veterinary technician students, and 165 farmers and extension educators were certified in FAMACHA during these workshops. Contact information and permission were obtained from 192 farmers to follow up on whether their methods of managing internal parasites, such as barber pole worm, changed after participating in these activities. An initial literature review and power point presentation on the use of COWP presented during a field day at the first farm participating in our COWP studies was put on-line at http://www.ansci.cornell.edu/goats/dwight_bowman.html for further reference by workshop participants. We have been invited to make three presentations on new innovations in sheep and goat parasite management at the Catskills Regional Agriculture Conference, the NOFA-NY Winter Conference, and the Northeast Pasture Consortium Conference.

Objectives/Performance Targets

Of 100 participating farmers surveyed, 75% will report deworming less and reducing their chemical dewormer costs by as much as $215 in a 100-doe or ewe flock, citing adoption of FAMACHA and other non-chemical internal parasite control methods. The low dose of COWP will reduce deworming cost by $142 compared with chemical dewormers with the added potential benefits of some farmers being able to meet organic farming standards and other farmers maintaining the effectiveness of selective use of chemical anthelmintics. Most importantly, these strategies both reduce deaths from internal parasites from as many as 18 animals per year to 5 animals per year, increasing income by $2,205 in a herd or flock of 100 mature females.

1. Three-thousand sheep and goat farmers learn about this research and extension project and are directed to an on-line survey about their methods of controlling H. contortus and other internal parasites. The survey has been written and is ready on line in our Survey Monkey account. An announcement is scheduled to go out in early 2014 asking the 3000 plus farmers in our sheep and goat extension database to fill out the survey.

2. Five-hundred farmers complete the survey and 300 agree to receive additional information about controlling H. contortus with minimal use of chemical anthelmintics. Announcement asking farmers to complete survey will be mailed out in early 2014.

3. Two-hundred farmers attend field days, workshops at regional conferences, or extension programs to learn directly about control of H. contortus and other internal parasites using COWP and other methods, such as FAMACHA scoring, evasive pasture management, and forages high in condensed tannins. Twelve farmers agree to do the research with COWP. As of December 5, 2013, 268 individual people have attended one or more of our integrated parasite management workshops describing COWP and other innovative methods with potential to help control barber pole worms (H. contortus). 192 farmers have provided follow up contact info to track how their parasite management changes.

4. One-hundred participating farmers respond to follow up questionnaires or interviews on changes made in internal parasite management. Seven farmers carry out the research with COWP. As of December 5, 2013, four Northeast sheep or goat farmers have carried out COWP studies for us using funding from other research sources and at least five other qualifying farmers have volunteered to participate in on-farm COWP research conducted with NESARE funds.

Accomplishments/Milestones

Our NESARE project has just started. Other than what we described in the previous section, there are few events and activities to report. Here, however, we will summarize some 2013 results from previously-funded studies that will inform our NESARE project.

In the summer of 2013 we conducted 4 on-farm trials with copper oxide wire particles (COWP).

The first trial was on a dairy goat farm. Sixteen, 15 and 15 lactating dairy goats at a commercial goat dairy were given HCOWP (1 g/22 lb live weight), MCOWP (2 g/head), or LCOWP (1 g/head), respectively. The two higher levels of COWP decreased barber pole worm fecal egg counts significantly after 14 days. There was no control group because of the farmer’s concern about losing milk if chemical deworming became necessary for untreated animals. The effect of COWP appeared to be short. The effect of time was significant (P < 0.013) and fecal egg counts generally increased from Day 14 to Day 42. FAMACHA scores increased in all the treatments over time. However, the quickest and largest increases were observed in LCOWP. In general, copper levels in milk increased slightly on Day 14 as compared to Day 0 but stayed within individual animal variations already exhibited prior to treatment. Copper levels in milk within each sampling day were not significantly different among the three treatments nor were the changes in copper concentration from Day 0 to Day 42 significant. 

The other three trials were in grazing lambs. Forty five lambs at each of three farms were randomly divided into Control (no COWP), LCOWP (0.5 g/head), or HCOWP (1 g/head) with 15 lambs per group. Pooled fecal samples were taken from lambs prior to starting the study. Based on egg counts, farmers decided to not deworm control animals at the initiation of the study. COWP appeared highly effective at both the 0.5 and 1 g/head dosages on Farm 1 where it was administered 2 weeks prior to weaning. The effect on this farm carried over for the full 42 days (28 days post weaning) of the study. However, COWP effects were more variable on Farms 2 and 3 where it was given several weeks post weaning and the study was carried out for 28 days. 

Studies for 2014 will focus on determining whether the timing of COWP administration in relation to weaning is an important determinant of the effectiveness of COWP in recently weaned lambs and goat kids. COWP will be given two weeks prior to weaning or two weeks post weaning to young stock from the same kid or lamb crop within farms to compare its effectiveness as a barber pole worm control in the 6 weeks following weaning. Levels of barber pole infection will be monitored at each farm prior to and during the studies. Pasture management practices that affect barber pole worm contamination will also be recorded. Both goat kids and lambs will be studied.

Starting in October 2012, we made a formal effort to integrate more information about COWP studies and research on other innovative parasite control methods into our IPM and FAMACHA workshops. Since then, 268 individuals have attended one or more of these workshops and 192 farmers have provided contact information to allow us to track whether participating in our parasite activities resulted in any changes in how they manage parasites. One hundred and ninety six people including 5 veterinarians, 23 vet or vet tech students, 165 farmers and 3 foreign veterinarians/grad students have become certified in FAMACHA during our 9 FAMACHA workshops. 

Results from pre and post tests were collected from most participants at 6 of 9 FAMACHA workshops. On average, the percentage correct increased 20 points between pre and post tests. A question asking farmers to fill out a chart identifying which dewormers are labeled for goats and which ones for sheep and which formulations can be used off label on each species was most problematic. After reviewing the test results and going over the materials that we actually want to be emphasizing in our IPM current workshops, we rewrote several test questions to better reflect our focus on innovative management practices rather than on specific dewormers. These new tests will be administered to participants in future workshops.

Impacts and Contributions/Outcomes

We are in the beginning year of our NESARE Parasite study and not ready to assess possible impacts. However, many Northeast goat and sheep raisers have already started using COWP. Unfortunately, COWP may be viewed by some as a panacea. Some farmers administer COWP as a dewormer substitute without incorporating other important aspects of an IPM program such as: 1) selectively treating animals and 2) monitoring worm populations and the effectiveness of COWP treatments by fecal egg count. Users may not be aware that COWP is considered effective only against barber pole worm and that, in the presence of brown stomach worm infections, the pH of the abomasum may increase and render the COWP insoluble thus making it ineffective as either a copper supplement or barber pole worm control. They may also administer COWP at times of year when barber pole worms are normally hypobiotic and not vulnerable to treatment. They may adopt COWP dosages recommended on popular blogs that are higher than recommended from research results. Researchers recommend lower dosages because the detrimental effect of COWP on barber pole worm is short lived and, in sheep, might result in copper toxicity. In a sustainable Integrated Parasite Management (IPM) program COWP may need to be repeated multiple times over the grazing period. In addition, SE US researchers recommend incorporating the use of COWP into FAMACHA programs rather than giving COWP to all animals at the same time regardless of need. 

The strong motivation of farmers to find new barber pole worm controls and to use COWP before it is well understood is pressuring us to move faster than anticipated to statistically analyze current data and to conduct more studies trying to identify why results from different herds or flocks are inconsistent. At this point, it is too early to say whether COWP will have a meaningful role in IPM on Northeast sheep and goat farms. The most we can currently say is that COWP appears to have promise and that lower dosages than those recommended in popular blogs may be adequate to sustain similar reductions with the advantage that they can be repeated over the grazing season.

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