Reducing parasite resistance on equine operations using a comprehensive, whole-farm approach

View the project final report

• 2014 annual report
• 2015 annual report
• 2016 annual report

Commodities

• Animals: equine

Practices

• Animal Production: animal protection and health, manure management, preventive practices
• Education and Training: extension, on-farm/ranch research
• Farm Business Management: budgets/cost and returns
• Production Systems: holistic management

Seventy-five percent of the 32,000 Pennsylvania equine operations are on limited acreage, requiring intensive management. A comprehensive parasite management system is needed that incorporates pasture and manure management BMPs, fecal egg count monitoring, and knowledge of parasite biology and behavior.  Most horse owners contribute to the development of resistant parasites by deworming horses every eight weeks and may use products that are totally ineffective. Indiscriminate use of dewormers has caused a drastic increase in cyathostomes and cases of resistant parasites are being reported worldwide. Recently, farms in Pennsylvania began reporting resistance to pyrantel-based dewormers. Benefits include: Reducing overall deworming frequency; targeting deworming to egg shedding horses; evaluating product efficacy; protecting viable products; reducing parasites load by composting and improving pasture management. Our hypothesis is that farm managers can reduce the use of anthelmintics by monitoring fecal egg production, identifying and target-deworming the “shedders” that have low parasite resistance and utilizing products that show individual farm efficacy. We also hypothesize that farms in Pennsylvania will have cyathostome populations that are resistant to pyrantel pamoate, fenbendazole, and oxibendazole. Farm managers will conduct bimonthly and pre and post deworming egg counts. Penn State and local veterinarians will serve as partners and will assist farm managers in developing farm specific programs and will provide industry recommendations utilizing the collected data. Participating farm managers will complete a short course on monitoring cyathostome egg production, parasite biology, and environmental implications for management.

• Indiscriminate use of dewormers has caused an alarming increase in cyathostomes.  Cases of resistant equine parasites are being reported worldwide.  Most horse owners contribute to the development of resistant parasites by deworming horses every eight weeks and may be using products that are totally ineffective.  The goal today is not to eliminate parasites but to utilize a comprehensive approach to reduce transmission, maintain parasites below harmful levels, and manage horses that maintain chronically high parasite levels.  Adoption of new deworming practices can decrease the proliferation of resistant parasites and maintain the effectiveness of the products that are available.  Monitoring fecal egg counts can identify horses with low parasite burdens, allowing a 30-50% deworming reduction.  Chronically high “shedders” can be identified and managed to reduce egg deposition on pastures. Utilizing a whole farm approach incorporates maintaining high quality pastures to reduce grazing near manure areas and adopting good manure handling practices. In order to empower horse owners to make changes in their deworming program, it is important to provide clientele with the knowledge and skills necessary to be confident they are making good management decisions.  To meet this need, a comprehensive parasite management short course, Piecing Together the Parasite Puzzle, will be offered throughout Pennsylvania.  Key collaborators include veterinarians, Extension Educators, pharmaceutical company representatives, farm managers, and NRCS and Conservation District personnel.  Topics include: types of parasites and parasite biology and behavior; the science of resistance and the importance of establishing a “non-resistant” refuge; conducting and using fecal egg counts; classes of dewormers and the danger of short interval deworming; pasture management and composting as a tool to reduce parasite burdens; and the effects of temperature, rainfall, pasture rotation and manure handling practices on parasite development and infection.  Individual assistance will be provided for farm managers who need help developing a program to manage parasites, compost manure or improve pastures.  The performance targets are as follows:

• 260 of 300 participants in the short course, Managing Equine Parasites using a Whole Farm Approach, will implement at least two new practices to reduce parasite burdens on pastures  (remove manure from pastures, improve pasture quality to reduce  grazing in manure deposition areas, rotate pastures after  deworming, deworm new individuals, compost manure before applying to pastures,  use fecal egg counts to strategically deworm “shedders”).    80 farm managers that completed  the course will use established protocol to conduct pre and post fecal egg counts , supplying data from 640 horses (average - 8 per farm) and will:   o   document egg shedding in horses enrolled in the project.   o   identify and eliminate the use of products that show resistance on their farms   o   identify and strategically deworm the “shedders” on their farm    o   eliminate 3 dewormings of all non-shedding  horses, resulting in an economic savings of $27 per horse annually.    

Monitoring and deworming protocol will be established by Penn State veterinarians. Eight Extension offices will be supplied with materials and equipment needed to monitor parasite egg production, including microscopes, flotation solution, and McMaster slides. To insure consistency in data collection, Extension personnel will be trained to provide technical assistance and ensure that proper protocol is followed. Farm managers will conduct bimonthly and pre and post deworming egg counts. Penn State and local veterinarians will serve as partners and will assist farm managers in developing farm specific programs and will provide industry recommendations utilizing the collected data. Key collaborators include veterinarians who will provide technical assistance, Extension Educators, and NRCS and Conservation District personnel who will help prepare training materials, teach workshops and provide assistance with manure composting, and parasite and pasture management .  Data on parasite levels and product efficacy will be compiled, analyzed and made available to horse owners and veterinarians nationwide, via abstracts, journal articles, and newsletters.