Economic values of rabbit traits in different production systems.

In animal breeding, genetic parameters along with economic weights (EWs) of traits are applied. Profit functions currently used to calculate rabbit traits' EWs do not consider nutrient requirements based on animal weight, growth rate and doe reproductive status. Therefore, the aim of this study was to develop a flexible bioeconomic model of rabbit-production systems and implement it in a computer programme in order to calculate economic values and relative EWs for rabbit traits. The bioeconomic model includes calculation of the doe age structure in the stationary state of a doe population; calculation of progeny structure; modelling growth, digestible energy, feed and water requirements for does in different reproductive statuses and for all progeny groups using a normative approach; calculation of the total feed and non-feed costs, revenues and profit per doe and per year; calculation of marginal economic values for up to 20 production and functional traits and estimation of the relative EWs of selected traits. The application of the programme is shown through an example calculation of trait economic values for a typical Czech commercial rabbit-production system. The trait economic value expresses the change in profit per doe and per year when the trait mean is increased by one unit. The programme developed is primarily useful for selection purposes in rabbit-breeding systems. Using this programme, some economic analyses of the impact of production, management and economic circumstances on the economic efficiency of various rabbit-production systems can also be performed.