2Gastro-intestinal worms Gastro-intestinal parasites (worms) pose the single greatest threat to the health and productivity of sheep and goats throughout most of the United States.
3The barber pole wormThe barber pole worm (Haemonchus contortus) is the worm species of primary concern in warm, moist climates, such as Maryland.It is a blood-sucking parasite that causes anemia and edema, production loss and sometimes death.
4Traditional control of parasites In the past, parasite control programs relied heavily upon the prophylactic use of anthelmintics.This approach is no longer sustainable due to the widespread emergence of drug-resistant worms.
6Materials and MethodsKatahdin and Katahdin crossbred lambs from the University of Maryland Eastern Shore’s sire comparison study were rotationally grazed from June 10 until Sept. 30 on 12.5 acres of cool season grass pastures. Stocking rate was ~7 lambs/acre.Kiko, Boer, and Kiko x Boer goats from the Western Maryland Pasture-Based Meat Goat Performance Test were rotationally grazed from June 10 until Oct. 6 on 10 acres of cool season grass pastures. Stocking rate ranged from 3 to 5 goats per acre.
9One lamb died due to ivermectin resistance. Results – Lambs (2005)The need for deworming peaked on July 11 when two-thirds of the lambs required an anthelmintic treatment.***One lamb died due to ivermectin resistance.
10Results – anthelmintic treatments # lambs% of flock# treatments2226.23541.711416.7267.1344.81.2584100.0The 84 lambs were dewormed an average of 1.25 times each vs. conventional parasite control which would have included 3 to 4 treatments.
13Results – Goats (2006)The need for deworming peaked on Aug 4 when two-thirds of the goats required an anthelmintic treatment.***No goats died.
14Results – anthelmintic treatments # goats% of goats# treatments412.91341.91722.6239.731100.0Excluding the initial treatment, the 31 goats were dewormed an average of 1.65 times each vs. conventional parasite control which would have included 3 to 4 treatments.