|Turner, Kenneth - Ken|
|BELESKY, DAVID - West Virginia University|
|CASSIDA, KIMBERLY - Michigan State University|
|ZAJAC, ANNE - Virginia Polytechnic Institution & State University|
|BROWN, MICHAEL - Retired ARS Employee|
Submitted to: Sheep and Goat Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/14/2016
Publication Date: 6/28/2016
Citation: Turner, K.E., Belesky, D.P., Cassida, K.A., Zajac, A.M., Brown, M.A. 2016. Selective deworming effects on performance and parameters associated with gastrointestinal parasite management in lambs and meat-goat kids finished on pasture. Sheep and Goat Research Journal. 31:17-29.
Interpretive Summary: Finishing lambs and meat-goat kids on improved pastures is a viable production system option for many producers in the USA. However, gastrointestinal parasite control is a significant socio-economic and management challenge for producers. To determine if providing whole cottonseed as a supplement would help reduce internal parasites in growing lambs and meat-goat kids finished on pasture, we evaluated fecal egg count, FAMACHA scores, and simple blood parameters in individual animals to help identify dewormer dosing needs and frequency. Providing whole cottonseed supplement at 0.5% of the animal’s body weight did not reduce fecal egg count in lambs and meat-goat kids. Katahdin lambs had less internal parasites (low fecal egg count, high blood albumin levels, and low blood globulin levels) than Suffolk lambs and goat kids. Whole cottonseed supplementation did not improve FAMACHA scores, but Katahdin lambs consistently had lower FAMACHA scores than Suffolk lambs and goat kids. The goat kids had the highest FAMACHA scores. Using FAMACHA scoring system as a means to identify internal parasite-induced anemia in individual animals resulted in a mean 56% reduction in doses of dewormer administered compared to a theoretical monthly dosing of each animal. Katahdin lambs were dewormed the fewest times and the meat-goat kids received the most doses of dewormer over the summer grazing season. By using breeds resistant to internal parasites and implementing the FAMACHA system to determine the need to deworm individual animals, producers can improve livestock performance and reduce cost of production. This information is useful to producers managing sheep or goats in pasture-based systems and researchers developing alternatives to chemical dewormers.
Technical Abstract: We evaluated health parameters associated with gastrointestinal parasite control when lambs and meat-goat kids were finished on a mixed sward of orchardgrass (Dactylis glomerata L.), red clover (Trifolium pratense L.), and white clover (Trifolium repens L.) with and without supplemental whole cottonseed (Gossypium hirsutum; WCS). Fecal egg count (FEC) was variable over the grazing season each year, but was not impacted by supplementation of WCS at 0.5% BW. Katahdin lambs had lower FEC than Suffolk lambs and goat kids. Goat kids and Suffolk lambs had lower (P < 0.001) blood albumin and higher (P < 0.001) globulin concentrations than Katahdin lambs. Supplementation with WCS did not improve FAMACHA© scores, but Katahdin lambs consistently had lower (P < 0.001) FAMACHA© scores than Suffolk lambs and Goat kids. The goat kids had the highest FAMACHA© scores. Using FAMACHA© as a means to identify Haemonchus contortus-induced anemia resulted in a mean 56% reduction in doses of dewormer administered compared to a theoretical monthly dosing of each animal. After the initial administration of dewormer, days to next dosing of dewormer were fewest for goat kids (33 d), followed by Suffolk lambs (67 d), and greatest for Katahdin lambs (77 d). By using breeds resistant to internal parasites and implementing the FAMACHA system to determine the need to deworm individual animals, producers can improve livestock performance and reduce cost of production.