Growth promotants in feeding pigs and poultry

The mode of action of antibiotic growth promoters in pigs and poultry production has been the subject of a great number of scientific investigations. This contribution reviews non-systemic and systemic effects. An important feature of this type of growth promoters is their regu- lating effects on the potentially harmful gut flora, thereby limiting gastro-intestinal infections. Ani- mal performance may be reduced as the immune system is stimulated by, e.g., gastro-intestinal infections or int7ammations. As a consequence, the cytokines may he produced by the organism affecting central nervous and/or the classical endocrine system or specific messenger cytokines may he released. Cytokines may also stimulate the release of catabolic hormones reducing body muscle mass. With respect to the systemic effects, it is tempting to assume that antibiotic growth promoters will alleviate challenges to the immune system through their gut flora regulating effects. (© Elsevier / Inra) growth promotant / antibiotic / pig / poultry / mode of action Rsum -Les promoteurs de croissance dans l'alimentation des porcs et des vollailes.