Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/17/2008
Publication Date: 3/9/2009
Citation: Burke, J.M., Wells, A., Casey, P., Kaplan, R.M. 2009. Herbal dewormer fails to control gastrointestinal nematodes in goats. Veterinary Parasitology. 160(1-2):168-170.
Interpretive Summary: Gastrointestinal nematodes represent a major health challenge to small ruminants and effective alternatives to chemical dewormers are needed for organic production. Herbal dewormers are available but have not been tested for effectiveness of control over Haemonchus contortus, an important nematode in warm, humid climates. Scientists at USDA, ARS in Booneville, AR and University of Georgia and ranchers at Heifer International determined that a commercial herbal dewormer failed to control gastrointestinal nematodes in goats. This information is important to producers, extension agents, veterinarians, organic certifiers, and scientists.
Technical Abstract: Gastrointestinal nematode (GIN) parasitism is the most important disease of small ruminants. Control is usually based on the use of chemical anthelmintics (dewormers); but these are prohibited from use in organic livestock, and the effectiveness of chemical anthelmintics in conventional operations is limited by high levels of anthelmintic resistance. Consequently, herbal dewormers are increasing in popularity as an alternative to chemical dewormers for GIN control. However, the effectiveness of herbal dewormers remains unproven. The objective of this study was to examine the effectiveness of a commercially available herbal dewormer to control GIN in goats. Lactating (n equals 16) and young (n equals 8) dairy goats grazed poor quality mixed grass pastures between March and July 2006 at the Heifer International Ranch in Perryville, AR. Goats were supplemented with grass hay and concentrate. Goats were untreated or administered herbal dewormer (n equals 12 pertreatment) according to manufacturer recommendations. FAMACHA scores (1 equals red or healthy; 5 equals severely anemic) were determined and fecal samples collected for fecal egg count (FEC) determination every 14 days between Days 0 (day of first herbal treatment) and 112. FAMACHA scores in the herbal treated group were greater than in the untreated control group (P less than 0.005), indicating a higher level of anemia. FEC were greater for herbal treated goats on Pasture A compared with B by Day 42, but similar among groups thereafter. FEC (P less than 0.03) and FAMACHA scores (P less than 0.001) were greater in lactating than in non-lactating goats. Herbal dewormer treatment yielded no measurable health benefits indicating that the herbal dewormer failed to control GIN in these goats.