Rearing conditions of palmipeds and fatty liver production: From societal demands to a process of progress

Abstract

The practice of palmiped overfeeding consists of introducing a tube (embuc) into the animals’ oesophagus to deposit increasing quantities of feed in order to produce “foie gras”. This practice is being questioned and strongly contested by animal welfare organisations, and a part of society. However, in the absence of an effective alternative, it remains the only way to produce “foie gras”, a product to which a majority of French people remain attached. This summary places “foie gras” production within the context of societal issues surrounding animal welfare and reviews scientific data on the impact of overfeeding in the broad sense (“embuc” introduction, feed load, housing) on various indicators of animal’s condition. In particular, it appears that i) overfeeding and liver hypertrophy are probably not nociceptive under normal overfeeding conditions; ii) animals are sensitive to capture and restraint; iii) liver function and histological structure are preserved and liver hypertrophy is reversible; iv) overfeeding induces behavioral changes: increased occurrence of drinking and panting without appearance of hypoxia; decreased occurrence of grooming; v) these behaviors also vary according to climatic conditions and housing configuration; vi) overfeeding can generate specific injuries (esophageal injury) when it is poorly performed and housing conditions of animals tend to aggravate pre-existing injuries (leg lesions); and vii) mortality rate increases during overfeeding. This article also reviews the knowledge and resources available to develop a method that would enable a multi-criteria assessment of the animal state, adapted to palmipeds during the overfeeding period, and that could be used on farms. Such an evaluation would make it possible to assess objectively the state of comfort or discomfort of animals and to support the “foie gras” production chain in a process of progress.