A stochastic model to investigate the effects of control strategies on calves exposed to Ostertagia ostertagi

Berk, Z., Laurenson, Y. C.S.M., Forbes, A. B. and Kyriazakis, I. (2016) A stochastic model to investigate the effects of control strategies on calves exposed to Ostertagia ostertagi. Parasitology, 143(13), pp. 1755-1772. (doi: 10.1017/s0031182016001438) (PMID:27573532) (PMCID:PMC5074087)

Abstract

Predicting the effectiveness of parasite control strategies requires accounting for the responses of individual hosts and the epidemiology of parasite supra- and infra-populations. The first objective was to develop a stochastic model that predicted the parasitological interactions within a group of first season grazing calves challenged by Ostertagia ostertagi, by considering phenotypic variation amongst the calves and variation in parasite infra-population. Model behaviour was assessed using variations in parasite supra-population and calf stocking rate. The model showed the initial pasture infection level to have little impact on parasitological output traits, such as worm burdens and FEC, or overall performance of calves, whereas increasing stocking rate had a disproportionately large effect on both parasitological and performance traits. Model predictions were compared with published data taken from experiments on common control strategies, such as reducing stocking rates, the ‘dose and move’ strategy and strategic treatment with anthelmintic at specific times. Model predictions showed in most cases reasonable agreement with observations, supporting model robustness. The stochastic model developed is flexible, with the potential to predict the consequences of other nematode control strategies, such as targeted selective treatments on groups of grazing calves.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Forbes, Dr Andrew
• Authors: Berk, Z., Laurenson, Y. C.S.M., Forbes, A. B., and Kyriazakis, I.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Parasitology
• Publisher: Cambridge University Press
• ISSN: 0031-1820
• ISSN (Online): 1469-8161
• Published Online: 30 August 2016
• Copyright Holders: Copyright © 2016 Cambridge University Press
• First Published: First published in Parasitology 143(13):1755-1772
• Publisher Policy: Reproduced under a Creative Commons License