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 or 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.

One meat goat farm and three sheep farms participated in five COWP on-farm studies during the 2014 grazing season. Two studies compared the effect of dosing lambs with three levels of COWP (0, 0.5 g, or 1 g) two weeks prior to weaning to dosing lambs at these two dosages two weeks post weaning. At another farm, COWP studies were done both on self-weaning lambs and lactating ewes comparing Clun Forest genetics with Romney X genetics. The fifth study looked at the effect of COWP dosing at 0, 0.5 g, or 1 g on barber pole worm infections is self-weaning Boer goat kids. The data are currently being analyzed but preliminary results indicate that while the COWP treatments were very effective when given either pre or post weaning on one sheep farm, there was far less efficacy at the other 3 farms. Given the popularity of COWP as a potential parasite control in sheep and goats, it is important that we determine what factors influence its efficacy and better education farmers about its limitations. 

There were 310 participants (some repeats) in four FAMACHA Certification workshops, six  “What’s new in sheep and goat parasite management” workshops and one on-farm field day organized by our sheep and goat parasite team during 2014. Eighty nine people were certified in FAMACHA and contact information and permission was obtained from 127 farmers to follow up on whether their methods of managing internal parasites such as barber pole worm undergo any changes after participating in these activities.

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.

Accomplishments/Milestones

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.

We invited our database of more than 3000 sheep and goat farmers to participate in the survey in May 2014. However, valid emails limited the list to approximately 2000 addresses and further mis-identification of our bulk email invitation as spam resulted in about 1200 addresses receiving the survey announcement.

2. Five-hundred farmers complete the survey and 300 agree to receive additional information about controlling H. contortus with minimal use of chemical anthelmintics. Of 194 respondents within one month of the invitation, 168 respondents fully completed the survey.

We were remiss in 1) not following up in later months with further reminders to fill out the survey, 2) not advertising it to various sheep and goat breed list servers, and 3) not advertising it on popular blogs and Facebook. However, as can be seen in the following milestone, attendance at our workshops providing information on controlling H. contortus with minimal use of chemical anthelmintics has easily exceeded 300 farmers.  

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. In 2014, approximately 310 attendees representing several Northeast states attended our 11 workshops, presentations or field days in NY and PA on innovative methods to control small ruminant parasites. Follow up contact information was provided by 127 goat and sheep farmers and 89 people became certified in FAMACHA.

4. Seven farmers carry out the research with COWP. One-hundred participating farmers respond to follow up questionnaires or interviews on changes made in internal parasite management.

In 2013, four NY sheep or goat farms participated in our COWP studies using funding from other research sources. In 2014, three sheep farms (one repeat) and one meat goat farm in NY participated in our 5 on-farm COWP studies conducted with funding from NESARE and other research sources.  We are also conducting studies on the effect of grazing Birdsfoot Trefoil on parasitic worm infections in sheep and goats. Six Northeast farms have established their BFT fields and plan to start grazing trials in July 2015. Two farms will be incorporating COWP dosing into these studies. In addition we will be conducting COWP studies on two New England farms and a study comparing pre and post weaning COWP on one New York meat goat farm. Follow up questionnaires to 2013 workshop participants as to changes they made during the 2014 grazing season will go out in Mar 2015 and follow up questionnaires for 2014 workshop participants will go out in Mar 2016. The later set of questionnaires will facilitate collecting information on the use of BFT as well as COWP, FAMACHA and evasive grazing as innovative parasite control methods.

Impacts and Contributions/Outcomes

On-farm studies

Studies for 2014 focused on determining whether the timing of COWP administration in relationship to weaning was an important determinant of the effectiveness of COWP in recently weaned lambs. At two sheep farms using primarily Dorset genetics, COWP was given two weeks prior to weaning and two weeks post weaning to young stock within the same lamb crop at three dosage levels (0, 0.5 g, or 1 g) for barber pole worm control in the 6 weeks following weaning. The same levels of COWP dosing were also evaluated in self-weaning lambs and Boer goat kids at two farms. On one farm the self-weaning lambs were further divided and compared for Clun Forest versus Romney genetics. The effect of three levels of COWP dosing (0, 1 g, or 2 g) and of genetics (Clun Forest versus Romney) on worm infection was also compared on the lactating dams. Pasture management practices and mineral composition of pasture and supplementary feed that might influence the effectiveness of COWP treatment were also recorded. Preliminary analyses indicate that COWP dosing was effective at reducing barber pole worm infections at one sheep farm both pre- and post-weaning but there was no effect on the other three farms. Further analyses of our data will provide better clues as to why the efficacy of COWP varies among flocks.

Outreach

Approximately 12% of respondents to our survey indicated that they had used COWP on their goats or sheep in 2013.  All but 2 farms had used it at higher dosages (commonly 4 g to adults and 2 g to young stand ock) than currently recommended by Southeast US researchers.  About 40% of respondents using it indicated that their primary reason was to supplement copper in goats. Some respondents were under the impression that it is effective against all worms while others used it in winter when barber pole worms are normally hypobiotic and not vulnerable to treatment. Verbal responses and “pre-tests” at 2014 workshops have also reinforced that users commonly use COWP at higher dosages than recommended by researchers. Many are also an unaware 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 and ineffective as either a copper supplement or for barber pole worm control. 

Results from pre and post tests were collected from participants at 4 of our parasite workshops. Test questions had been rewritten to better focus on testing participant knowledge of innovative management practices. The percentage correct increased from 67, 68, 62 and 68% for pre-tests to 84, 84, 78 and 82% for post tests at the 4 workshops respectively. Workshop participants appeared to gain a better understanding of the principles behind using FAMACHA, evasive grazing techniques, and potentially COWP and high tannin forages as part of an integrated parasite management program. However, until researchers better understand why COWP effectiveness varies so widely, we are limited in the reliability of our own advice to farmers.

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