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Nutrient partitioning between reproductive and immune functions in animals

Published online by Cambridge University Press:  28 February 2007

Jos G. M. Houdijk ,
Neil S. Jessop  and
Ilias Kyriazakis
Jos G. M. Houdijk*
Affiliation:
Animal Nutrition and Health Department, Animal Biology Division, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
Neil S. Jessop
Affiliation:
Institute of Ecology and Resource Management, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JG, UK
Ilias Kyriazakis
Affiliation:
Animal Nutrition and Health Department, Animal Biology Division, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
*
Corresponding Author: Dr J. G. M. Houdijk, fax +44 131 535 3121, email j.houdijk@ed.sac.ac.uk
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Abstract

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The physiological processes that underlie the reproductive cycle impose considerable metabolisable protein (MP) demands on a female, especially during the periparturient period. When MP supply falls short of MP demand (i.e. MP becomes scarce), certain, if not all, bodily functions are expected to be penalised. It has been proposed that partitioning of scarce MP is prioritised to reproductive rather than to immune functions. In other words, at times of MP scarcity, the penalty on expression of immunity would be expected to be greater than that on reproduction. This hypothesis forms a nutritional basis for the occurrence of periparturient breakdown of immunity to parasites (BIP), which can be observed in many host–parasite systems. In the present review we explore this nutritional basis, using periparturient sheep infected with the abomasal nematode Teladorsagia circumcincta as an example, and attempt to quantify its occurrence. Evidence supporting the nutritional basis of periparturient BIP is reviewed, covering experiments in which nutrient supply (from both exogenous and endogenous sources) and/or nutrient demand were manipulated. Quantitatively, MP requirements for expression of immunity to T. circumcincta were estimated to be about 1 g/kg metabolic body weight (body weight0·75) per d, approximately 5 % of the maximum MP requirements of periparturient sheep. The major component of this requirement was assumed to be for replenishing irreversible plasma protein losses into the gastrointestinal tract. Although confirmation of this estimate is required, such estimates may be used to improve the known MP requirements of periparturient animals, enabling the extent and the consequences of periparturient BIP to be minimised.

Keywords

Nutrient partitioning around parturitionImmunity to parasitesProtein requirements of sheep
Type
Symposium on ‘Nutritional adaptation to pregnancy and lactation’
Information
Proceedings of the Nutrition Society , Volume 60 , Issue 4 , November 2001 , pp. 515 - 525
Copyright
Copyright © The Nutrition Society 2001

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