Gut health in the pig

Gastrointestinal disturbances can cause large economic losses in the pig industry. Diseases and conditions of the gastrointestinal tract (GIT) that can cause economic loss have generally been controlled by the use of dietary (and or in the water) antimicrobial compounds, such as antibiotic feed additives and (or) minerals such as zinc and copper. However the implementation of legislation in some parts of the world, for example the European Union, and a growing sentiment worldwide to reduce the use of dietary antimicrobial compounds, has caused a reassessment of measures to influence GIT 'health' and caused enormous interest in alternative means to control diseases and conditions of the GIT. There are now available a wide array of products and strategies available to the pig industry that influence 'gut health'. The products in the market place are characterised predominately not only by their (claimed) different modes of action, but also by the variation in responses seen when offered to pigs, and not only in the post-weaning period. This variation is presumably a consequence of the many different conditions of management that pigs are under, that in turn influences factors such as composition of the microbiota and mucosal immunity. Other strategies, such as the manipulation of particle size and changing the protein content of a diet, might also be adopted to influence the expression of enteric pathogens and the expression of disease. Ultimately, the cost-benefit of adopting such practices to influence gastrointestinal 'health' requires consideration.