Abstract

The behaviour and physiology of lambs with gastrointestinal nematode infections (GIN) was evaluated. Thirty 8-month-old Romney wethers were assigned to one of two treatments (n=15/treatment) trickle dosed with either 1500 infective third stage larvae 3 days/week for 6 weeks (27,000 total L3; challenged), or water 3 days/week for 6 weeks (control). Blood and faecal samples were collected weekly during the study. Lipidomics were performed on plasma samples. Behaviour was observed from video-camera recordings once weekly over the study. At treatment week 4, specific triglycerides were elevated in the challenged lambs compared to controls (P≤0.05). Faecal egg counts were higher in challenged than control lambs from treatment week 4 (154 epg; P≤0.001). Challenged lambs had higher standing bouts at week 4 than baseline (5.6 bouts) whereas there were no differences in standing bouts for control lambs between baseline and week 4. Triglycerides and standing behaviour show promise for early identification of GIN.

MN, Hempstead, TS Waghorn, MJ Gibson, CW Sauermann, AB Ross, VM Cave, MA Sutherland, and IA Sutherland

New Zealand Journal of Animal Science and Production, Volume 82, Online, 104-107, 2022