Les truies libres en maternité : modalités de logement et de conduite, performances, conditions de travail et bien-être

Freedom of movement for sows in the farrowing building is an approach that improves animal welfare. Many types of housing pens exist for sows and their piglets, and differ according to the area required, the type of flooring and the presence of protective components for the piglets. The study and experimental results obtained since the beginning of the 2000s at stations in the Chambers of Agriculture in Brittany and the Pays de la Loire, supplemented with a literature review, describe the factors required to successfully house and manage animals. According to the results obtained on the experimental farm in Guernevez, the average number of crushed piglets increases to 0.5 piglets per litter when the sows move freely. High variability was observed among the animals, which is related to the general behaviour of the sow and its bedding behaviour. The cost of a farrowing system with freedom of movement is estimated at 33% more than a conventional crate; the required area is larger and the equipment is more robust. For animal welfare, the issue is the balance between providing freedom of movement to the sow and the risk of increased mortality for the piglets. Confining the sow in a stall for 4 to 7 days after farrowing is a way to decrease piglet mortality and maintain the mobility of the sow during the lactation period. Considering the technical conditions required for success is essential since current commercial and regulatory initiatives in Europe promote the development of loose-house farrowing systems for sows.Libérer les truies en maternité demande de maitriser des aspects techniques, sur le logement en particulier. Mais la conduite des animaux est aussi essentielle pour garantir de bonnes conditions de travail, les performances de production et le bien-être des porcs. Des truies sont libres en maternité dans les stations expérimentales des Chambres d'agriculture de Bretagne, et celle des Pays de la Loire. La présente synthèse fait le point sur les différents aspects de la liberté pour les truies à partir de données de la bibliographie et de l'expérience acquise dans les stations expérimentales en France