|Williams, Mary - Mimi|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/26/2007
Publication Date: 5/4/2007
Citation: Burke, J.M., Kaplan, R.M., Miller, J.E., Terrill, T.H., Getz, W.R., Mobini, S., Valencia, E., Williams, M.J., Williamson, L.H., Vatta, A.F. 2007. Accuracy of the FAMACHA system for on-farm use by sheep and goat producers in the southeastern United States. Veterinary Parasitology. 147(1-2):89-95. Interpretive Summary: Widespread resistance of gastrointestinal worms to chemical dewormers has led to the need for alternative parasite control. The FAMACHA system, a tool to classify color of lower eye lid into stages of anemia which correlates with Haemonchus contortus infection, has not been tested on-farm for use in the U.S. ARS scientists from Booneville, AR and Brooksville, FL, and cooperating scientists from Fort Valley State University, University of Georgia, Louisiana State University, University of Puerto Rico, and Onderstepoort Veterinary Institute, South Africa determined that the FAMACHA system can be used by producers and is a valuable tool for identifying anemic sheep and goats for treatment against H. contortus. These results indicate that the FAMACHA system aids in the control of H. contortus and this information is important to producers, extension agents, and scientists.
Technical Abstract: FAMACHA is a practical on-farm system designed to provide small ruminant producers a tool for improving their management of Haemonchus contortus infections. Although this system has become very popular and widely accepted by small ruminant producers in many regions of the southern United States, there is very limited data reported on the effectiveness of the FAMACHA system when performed by farmers. The objective of this study was to evaluate the accuracy of the FAMACHA system for on-farm use by small ruminant producers during the summer season. Small ruminant producers from Georgia, Louisiana, Florida, and Puerto Rico were trained to use the FAMACHA system by veterinarians and scientists experienced with this method. FAMACHA scores were assigned at least every two weeks by producers to weaned and mature sheep (n = 552) and goats (n = 676) of various breeds and ages between April and September 2004. At intervals that varied among farms from two to eight weeks, researchers determined body condition scores (BCS; 1 = thin, 5 = fat), and collected blood and feces from a group of animals selected randomly, to determine packed cell volume (PCV) and fecal egg counts (FEC). Two separate anemia thresholds were evaluated; these were defined by either FAMACHA score (+/- 3 vs. +/- 4) or PCV (+/- 19 vs. +/- 15%). The correlation between FAMACHA scores and PCV or FEC was high for both sheep and goats (P < 0.001). Specificity was maximized when FAMACHA scores of 4 and 5 were considered anemic, but sensitivity was low. Sensitivity for detecting anemic animals was 50% for sheep and 89% for goats when eye score values of +/- 3 were considered anemic and PCV cut off was +/- 15%. The percentage of false negatives (anemic animals not identified by FAMACHA evaluation) was less than 5% in sheep and less than 1% in goats when FAMACHA scores +/- 3 were considered anemic and PCV cut off was +/- 15%. In both sheep and goats, predictive value of a negative was greater than 90% for all anemia and eye score categories. These data indicate that the FAMACHA method used by producers is a valuable tool for identifying anemic sheep and goats in the southern United States and Puerto Rico.