A Multi-Attribute Utility Model to Optimise Sow Replacement Decisions

An existing stochastic dynamic programming model is expanded so that its output can be used as input to a multi-attribute utility model to determine the optimal replacement policy in swine breeding herds. The models include six attributes: future profitability of the sow (from the dynamic programming model), piglet mortality rate, pigs crushed by the dam, savaged and stillborn pigs, undersized pigs at birth, and undersized pigs at weaning. The aim is to rank sows for replacement purposes. The model provides stable rankings that differ from those based only on the dynamic programming model. There was good correspondence between the model@ ranking of 30 sows and rankings provided by two experts. Copyright 1998 by Oxford University Press.