Gastrointestinal nematode parasites of sheep: A dynamic model for their effect on liveweight gain

Authored by K Louie, A Vlassoff, A D Mackay

Date Published: 2007

DOI: 10.1016/j.ijpara.2006.09.013

Sponsors: New Zealand Foundation for Research Science and Technology

Platforms: No platforms listed

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

This paper presents an individual-based model for gastrointestinal nematode parasites of sheep and includes the effect of these parasites on the liveweight performance of young sheep. Parasitism is known to affect the host animal in at least two ways. The first induces a loss of appetite in the host, which reduces pasture consumption compared with the parasite-free animal. This effect is examined in the first part of the study. The second major effect of parasitism is a reduction in the metabolic efficiency of the host which decreases nutrients available for maintenance and growth. The latter part of the paper examines the consequences of incorporating this effect on the liveweight changes in individuals in a group of sheep. Previous models addressing this issue have only given mean liveweight and worm burden changes. (c) 2006 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Tags

Epidemiology Infections Food-intake Nutrition Ostertagia-circumcincta larvae Trichostrongylus-colubriformis Growing lambs Body-composition Grazing sheep Ruminants