Date of Graduation


Document Type


Degree Name

Bachelor of Science in Agricultural, Food and Life Sciences

Degree Level



Animal Science


Rick, Rorie

Committee Member/Reader

Burke, Joan

Committee Member/Second Reader

Coffey, Ken



Anthelmintic resistance (AR) urges alternatives to control gastrointestinal nematodes (GIN). Copper oxide wire particles (COWP) are more efficacious when used with other dewormers and little is known on efficacy of diatomaceous earth (DE) to control gastrointestinal parasites. The objective was to examine the effects of DE and COWP on GIN control. Katahdin lambs (n = 32; ~150 d of age; 25.0 ± 1.8 kg) were randomly assigned to receive: 1) DE fed at an estimated 2% dry matter intake (with the assumption of moderate consumption of bermudagrass forage and provided supplement), 2) 1g COWP, 3) both 2% DE and 1g COWP, and 4) neither DE or COWP. Feces and blood were collected on d 0, 7, 14, 21 and 28 to determine fecal egg counts (FEC) and blood packed cell volume (PCV). Feces were cultured to determine GIN genera. Fecal egg counts were log transformed; data were analyzed as a 2 x 2 factorial arrangement using Proc Mixed of SAS with day as a repeated measurement. There was a mixed GIN population including 58% Haemonchus contortusand 30% Trichostrongylus spp.Fecal egg counts tended to be lower by d 28 in DE (175 eggs/g) than no DE (753 eggs/g) fed lambs (P = 0.09), but in general, were relatively low and no other differences among treatments detected. Packed cell volume tended to be higher in COWP than no COWP lambs by d 28 (P = 0.10), and no other differences detected. In conclusion, during a low GIN challenge, there may have been a small effect of DE on FEC, but no advantage observed in combination treatment.


copper, diatomaceous earth, internal parasites, sheep