Sustainable Control of Gastrointestinal Nematodes in Small Ruminants using Forages Containing Condensed Tannins

Final Report for LS04-164

Project Type: Research and Education
Funds awarded in 2004: $15,500.00
Projected End Date: 12/31/2007
Region: Southern
State: Georgia
Principal Investigator:
Will R. Getz
Fort Valley State University
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Project Information


A team of researchers, extension specialists, and producers from AL, AR, DE, GA, KY, LA, MD, NC, OK, TX, VA, WV, Puerto Rico, the USVI, Denmark, and South Africa, making up the Southern Consortium for Small Ruminant Parasite Control (, met for a series of research and outreach planning workshops from September, 2004 – October, 2007. In addition to planning on-going work from previously-funded projects on preservation of the efficacy of chemical anthelmintics, development and implementation of alternative, non-chemical small ruminant control methodologies, and widely disseminating findings to clientele groups through producer workshops, these meetings resulted in a number of additional successful grants from SARE (R & E, PDP, Graduate Student), the 1890 Institution Research and Teaching Capacity Building Program (USDA), the Organic Production Improvement Program (USDA), the Sheep and Goat Improvement Association, and the Morris Animal Foundation.

Project Objectives:

1. To assemble a multi-disciplinary, multi-institution team of researchers, extension personnel, producer organization leaders, and farmers to discuss, prioritize, and plan a field-based research program using bioactive forages and other forage/grazing strategies for sustainable control of small ruminant GIN in the southern USA, Puerto Rico, and the US Virgin Islands.

2. To develop an education and outreach plan to effectively share research results and prepare informational material for appropriate clientele groups throughout the southern SARE region.

3. To develop a full proposal for submission to the Southern Region SARE Program


Problem: The major constraint to economic small ruminant production in the southern USA and throughout the world is infection with gastrointestinal nematodes (GIN), particularly Haemonchus contortus, the barber pole worm. Haemonchosis, caused by blood feeding activity of H. contortus in the abomasum, can result in severe anemia and death losses, particularly in young kids and lambs (Miller, 1996; Williams, 1981). Warm, moist environmental conditions in the Southeast are ideal for the survival and growth of H. contortus larvae on pasture. Under favorable conditions, parasite numbers on pasture can rapidly build to dangerous levels.

The primary method of GIN control in small ruminants remains use of broad-spectrum anthelmintics despite overwhelming evidence of resistance to drugs from all of the major families of anthelmintics in sheep and goat GIN (Terrill et al, 2001; Mortensen et al., 2003; Kaplan et al., 2007). Development of new drug classes for use in small ruminants is not likely in the foreseeable future because of the high costs associated with drug development and the relatively small market for these drugs for use with sheep and goats (Geary et al., 1999).

Rationale: Use of anthelmintic drugs alone to control GIN infection in sheep and goats is not a sustainable strategy, and this approach has led to the current epidemic of anthelmintic resistance. A more sensible and sustainable approach is to take steps to preserve whatever efficacy is left in currently available drugs while incorporating effective novel (non-chemical) GIN control technologies in integrated, producer-friendly programs. This has been the basic strategy of the SCSRPC, and we have had encouraging successes with this approach. In validating the FAMACHA system of anemia detection for use in sheep and goats in the USA, we now have a useful tool for reducing overall use of anthelmintics by producers, while also preserving existing anthelmintic efficacy. With the FAMACHA system, the color of the lower eyelid is compared to colors on a laminated chart from red (healthy) to white (severely anemic) to determine animals most in need of treatment. Because approximately 20% of the animals will harbor 80% of the GIN, identifying and treating only that 20% greatly saves on anthelmintic costs and also allows culling of the most susceptible GIN carriers, improving the genetics for GIN resistance in the herd or flock.

Two successful non-chemical GIN control methodologies that have been developed by the Consortium are use of copper oxide wire particles (COWP) and forages high in condensed tannins (CT), particularly sericea lespedeza (Lespedeza cuneata). The COWP are given to sheep or goats as a bolus, whereas CT forages can be grazed or fed as hay in unground, ground, or pelleted form. In the latter case, each of these forms of sericea lespedeza has been shown to be effective against H. contortus in both sheep and goats. A goal of the Consortium is to develop control programs using combinations of these 3 technologies, and others that prove successful in the future, that can be adapted for use on individual farms.

Significance: Widespread anthelmintic resistance has led to the failure of many small ruminant production operations in countries like New Zealand, South Africa, Great Britain, and the USA. Total drug failure has been documented in goat herds in the USA (Kaplan et al., 2007). In addition, drug resistant GIN are now being found in horses, beef cattle, camelids (llamas and alpacas) and exotic species (zoological parks) in many parts of the USA. Development of environmentally-safe biological agents for control of GIN that can be incorporated into sustainable, forage-based feeding systems and could greatly impact production systems for all of these species, but particularly for small ruminants in the Southeast and throughout the world. Reduced use of anthelmintics and improved herd or flock resistance will increase producer’s bottom line by lowering production costs while improving animal productivity.


Click linked name(s) to expand/collapse or show everyone's info
  • Garth F. Bath
  • Joan Burke
  • Steve Hart
  • D. Dickinson Henry
  • Ray Kaplan
  • Michael Larsen
  • James Miller
  • Seyedmehdi Mobini
  • Jorge Mosjidis
  • James Muir
  • Tobe Named
  • Thomas Terrill
  • Elide Valencia
  • Adriano Vatta
  • Mimi Williams
  • Anne Zajac


Materials and methods:

Objective 1.

A team of scientists, extension personnel, small ruminant organization leaders, and farmer collaborators from Alabama, Arkansas, Delaware, Florida, Georgia, Louisiana, Kentucky, Maryland, North Carolina, Oklahoma, Texas, Virginia, West Virginia, Puerto Rico, the US Virgin Islands, Denmark, and South Africa met at various locations throughout the southern USA from September, 2004 to October, 2007, to discuss and plan research and outreach concerning use of CT-containing forages in combination with other non-chemical strategies for small ruminant GIN control in southern USA, Puerto Rico, and the US Virgin Islands. One planning meeting was held yearly at the Fort Valley State University Agricultural Research Station (October, 2004; 2005; 2006; 2007), and a second yearly meeting was held at different locations throughout the South (May, 2005 – Texas; August 2006 – North Carolina; May 2007 – Virginia). At each meeting, reports are given by Consortium members on on-going research and outreach activities and planned activities for the coming year, including proposals to be submitted to various funding agencies.

Experiments that were discussed and planned included feeding trials with unground, ground, and pelleted sericea lespedeza hay for various breeds and ages of sheep and goats, and grazing trials with sericea, either in pure stands or as a deworming paddock in rotation with non-CT forage pastures. Additional projects planned and discussed at these meetings included screening of a wide range of tropical, subtropical, and temperate legumes and legume trees for CT content and in vitro activity against small ruminant GIN.

At each meeting, university and on-farm research protocols were discussed, prioritized, and planned in detail, with minutes were kept and distributed to all collaborators.

Objective 2.

The team discussed and planned the development of an effective education and outreach program to share university and on-farm field research results with appropriate clientele groups. Outreach activities discussed and planned at each meeting included on-going FAMACHA and Smart Drenching Workshops held in each participating state/region, development of a producer workshop concerning establishment and management of sericea lespedeza for hay and grazing to control small ruminant GIN, and development of a ‘train the trainer’ curriculum on general principles of sustainable GIN control methods. Plans were discussed for implementation of the new workshops (including the train the trainer curriculum) in each state/region represented by Consortium members.

In addition to workshops, project updates and research results were distributed to appropriate clientele groups in a quarterly newsletter published by the Georgia Small Ruminant Research and Extension Center (GSRREC) at FVSU, and through our Consortium web site ( Discussions on strategies to improve outreach activities of the Consortium were a regular component of each of our planning meetings. Several producer-friendly publications were developed and posted on our web site as a result of these discussions.

Objective 3:

Based upon the discussions and planning completed in conjunction with Objectives 1 and 2, a full proposals were developed for submission to the Southern Region SARE Program, the 1890 Institution Research and Teaching Capacity Building Program (USDA), the Organic Production Improvement Program (USDA), the Sheep and Goat Improvement Association, and the Morris Animal Foundation.

Research results and discussion:

This planning grant was instrumental in the continued expansion and development of the Southern Consortium for Small Ruminant Parasite Control (SCSRPC), which is currently recognized as one of the leading small ruminant parasitology research and outreach groups in the world and now includes members from institutions in Alabama, Arkansas, Delaware, Florida, Georgia, Louisiana, Kentucky, Maryland, North Carolina, Oklahoma, Texas, Virginia, West Virginia, Puerto Rico, the US Virgin Islands, and South Africa. Since this planning grant was funded in September, 2004, SCSRPC members have written a number of successful grants related to this work, including SARE R & E (2), PDP (1), and graduate student grants (3), 1890 Instituition Research and Education Capacity Building Program grants (2), and grants from the Sheep Improvement Association (1), the Morris Animal Foundation (1) and the USDA Organic Production Improvement Program (1). Consortium members have published refereed journal papers, proceedings papers, and numerous abstracts related to this project since September, 2004. Since 2004, SCSRPC members have sponsored over 200 producer or county agent ‘smart drenching’/FAMACHA training sessions (approximately 5000 participants) in 12 states, Puerto Rico, and the US Virgin Islands. Approximately 12,000 FAMACHA cards have been sold for direct on-farm use since 2004. Our group’s web site ( is updated at least monthly and more often when needed and has had over 40,000 hits since September, 2004.

Participation Summary

Educational & Outreach Activities

Participation Summary:

Education/outreach description:

Several successful grants were written by the Southern Consortium for Small Ruminant Parasite control as a result of meetings funded by this SARE planning grant:

T.H. Terrill, W.R. Getz (Fort Valley State University, FVSU), J.E. Miller (Louisiana State University, LSU), J.P. Muir (Texas A & M University, TAMU), J.A. Mosjidis (Auburn University, AU), and N. Whitley (University of Maryland Eastern Shore, UMES). Development and field testing of natural (non-chemical) systems for control of gastrointestinal nematodes in sheep and goats. USDA/1890 Institution Research Capacity Building Program submitted by FVSU on February 28, 2007.
Requested Amount $500,000
Outcome: Funded for $460,000

T.H. Terrill (FVSU). Novel methods for sustainable control of gastrointestinal nematodes in llamas and alpacas in the southeastern United States. USDA/Sustainable Agriculture Research and Education (SARE) Graduate Student Grant submitted by FVSU in June, 2006.
Requested Amount $10,000
Outcome: Funded

T.H. Terrill, W.R.Getz, S. Mobini (FVSU), J.E. Miller (LSU), M.J. Williams (USDA/ARS Subtropical Agricultural Research Station, STARS, Brooksville, FL), R.M. Kaplan (The University of Georgia, UGA), J.M. Burke (USDA/ARS Dale Bumpers Small Farms Research Center, DBSFRC, Booneville, AR), J.A. Mosjidis (AU), and S. Hart (Langston University, LU). Use of condensed tannin-containing plants to control gastrointestinal nematodes in sheep and goats in the southern USA. Submitted by Fort Valley State University in February, 2005 to USDA/1890 Institution Capacity Building Program.
Requested Amount $500,000
Outcome: Funded

T.H. Terrill, W.R.Getz, S. Mobini, S. Gelaye (FVSU), J.E. Miller (LSU), M.J. Williams (USDA/ARS/STARS), R.M. Kaplan (UGA), E. Valencia (The University of Puerto Rico, UPR), J.M. Burke (USDA/ARS/DBSFRC), J.A. Mosjidis (AU), S. Hart (LU), and D. Henry (Bellwhether Solutions, Tallahassee, FL). Sustainable Control of Gastrointestinal Nematodes in Small Ruminants. USDA/SARE Research and Education Grant submitted by FVSU on November 15, 2004.
Requested Amount: $278,000
Outcome: Funded for $250,000

L. Williamson (UGA), T.H. Terrill (FVSU), and R.M. Kaplan (UGA). Prevalence of anthelmintic resistant gastrointestinal nematodes in camelids. Morris Animal Foundation grant submitted by the University of Georgia in April, 2006.
Requested Amount: $66,295
Outcome: Funded
FVSU Subcontract: $29,500

Mobini, S., T.H. Terrill, W.R. Getz (FVSU), J.E. Miller (LSU), M. Larsen (RVAU), M.J. Williams (USDA/ARS/STARS), R.M. Kaplan (UGA), E. Valencia (UPR), J.M. Burke (USDA/ARS/DBSFRC), J. Mosjidis (AU), J. Muir (TAMU), S. Hart (LU), S. Weiss (UVI), L. Williamson (UGA), A. Vatta (OVI), A. Zajac (VPI&SU), G.A. Bath (UP), and J.A. van Wyk (UP).
Smart Drenching and FAMACHA Integrated Training for Sustainable Control of Gastrointestinal Nematodes in Small Ruminants. SARE Professional Development Program Grant submitted by Fort Valley State University on June 1, 2005.
Requested Amount: $145,910
Outcome: Funded for $72,000

J. Muir (TAMU), T.H. Terrill, W. R.Getz (FVSU), M. J. Williams (USDA/ARS/STARS), E. Valencia (UPR), S. Weiss (UVI), A.A. Rodriguez-Carias (UPR). Sustainable and profitable control of invasive species by small ruminants. SARE R & E Grant submitted by Texas A & M University on November 15, 2004.
Requested Amount: $271,666
Outcome: Funded for $178,000
FVSU Subcontract $ $43,050

Burke, J.M (USDA/ARS/DBSFRC), T.H. Terrill (FVSU), J.E. Miller (LSU), J. Muir (TAMU), J. Mosjidis (AU), M. Larsen (RVAU), M. J. Williams (USDA/ARS/STARS). Development of gastrointestinal nematode control in organic small ruminant production. USDA Grant submitted by USDA, ARS, DBSFRS in May, 2005
Requested Amount: $299,632
Outcome: Funded
FVSU Subcontract: $62,409

Project Outcomes

Project outcomes:

The work that was initiated by this planning grant has greatly increased awareness of the potential of using CT-containing forages, either through grazing or fed as hay, meal, or pellets, to control gastrointestinal nematodes in small ruminants. One indicator of the impact of the work has been the greatly increased demand for sericea lespedeza seed according to Sim’s Brothers Seed Company of Union Springs, AL, who are the exclusive distributor of ‘AU Grazer’, a grazing-tolerant sericea. Another impact of this work is generally increased producer acceptance of alternative (novel) strategies to control gastrointestinal parasites in sheep and goats, and the need for combinations of strategies instead of waiting for the next anthelmintic ‘silver bullet’ to come along. This has been demonstrated in a greatly increased volume of calls from producers asking about the use of copper oxide wire particles and sericea lespedeza as anti-parasitic agents in combination with FAMACHA.

Economic Analysis

Economic analysis was not a part of this planning grant.

Farmer Adoption

As this was a research and outreach planning grant, farmer adoption does not apply.


Areas needing additional study

Additional research and outreach is needed in the area of development of producer-friendly combinations of parasite control strategies that can be tested on-farm. Also, developing new and more efficient delivery methods for novel control technologies needs more research.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.