Feed efficiency in rabbit production: nutritional, technico-economical and environmental aspects

Feed accounts for the largest part of the production costs in animal production. Therefore feed efficiency, mostly expressed as feed conversion ratio (FCR), is a key indicator to judge the performance and profitability of a farming system. In intensive rabbit breeding, the global farm FCR (maternity + fattening units) decreased from 3.8 to 3.4 in European farms during the past 15 years. By consequence, nitrogen and phosphorus output were reduced by approximately 10%. This improvement sources from a joint progress in: health control, nutritional factors and strategies, management and genetic progress. In order to optimize farms’ FCR both the reproducing stock as the fattening unit have to be considered. This review summarizes the impact of different strategies to optimize FCR under intensive production conditions, in which rabbits are fed exclusively a pelleted diet. High performing reproduction stock results in a reduced FCR in the maternity. The use of diets with nutrient levels to optimize digestive health, together with an appropriate feeding restriction after weaning, leads to minimal losses and has a large impact on the FCR. If the different fibre requirements are met, an increase of the dietary energy level, especially in the finishing stage, reduces the FCR with approximately 0.15 points for an increase of 0.5 MJ DE. In the future, it seems possible to improve further the feed efficiency, and thus to reduce both the inputs and output to reach a global farm FCR of 3.0, similar to that recorded in pig breeding.