Chalmers Conferences, 9th European Conference on Mathematical and Theoretical Biology

Grazing strategies for the control of gastrointestinal nematodes in sheep: a stochastic model in a seasonal environment.
Martin Lopez Garcia

Last modified: 2014-05-05


In this talk, we present a nonlinear stochastic model studied in [1,2] for the development of gastrointenstinal nematode infection in growing lambs under seasonal conditions, which are model by nonhomogeneous Poisson processes governing the acquisition of parasites, the parasiteinduced
and no parasite-induced host mortality, and the death of parasites within the host. Our interest is in individual-based grazing strategies which imply the movement or the anthelmintic treatment of the host at certain instant t_0. Two stochastic control criteria are presented in order to select the optimal instant t_0, as well as to compare between the convenience of the different
grazing strategies under consideration. Numerical results are obtained with empirical data from the literature.

[1] Gomez-Corral A, Lopez Garcia M (2013) Control strategies for a stochastic model of hostparasite
interaction in a seasonal environment. Journal of Theoretical Biology, in press. DOI:
[2] Gomez-Corral A, Lopez Garcia M (2013) Grazing management strategies for the control of
gastrointestinal nematodes in sheep: a study based on stochastic control criteria. Ecological
Complexity, under review.


host-parasite interaction; nematode infection; seasonal environment; nonhomogeneous Poisson processes