Gastro-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.
The barber pole worm The 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.
Traditional 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.
Materials and Methods Katahdin and Katahdin crossbred lambs from the University of Maryland Eastern Shores 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.
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.
Results – anthelmintic treatments The 84 lambs were dewormed an average of 1.25 times each vs. conventional parasite control which would have included 3 to 4 treatments. # lambs% of flock# treatments
The need for deworming peaked on Aug 4 when two-thirds of the goats required an anthelmintic treatment. *** No goats died. Results – Goats (2006)
Results – anthelmintic treatments # goats% of goats# treatments Excluding 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.