Pig ; an animal model in biomedical research.

A report documented in the Nature Microbiology, shows the many types of bacteria that inhabit the gut of pig and how they are important to health and disease. This knowledge of genes of these bacteria and their function therefore constitutes the first step towards a more comprehensive understanding of how bacteria in the gut affect health and disease. Pig is a main livestock species for food production worldwide and is also widely used as an animal model in biomedical research. The researchers analyzed stool samples from 287 pigs representing different breeds and selected pig lines from 11 different farms in France, China and Denmark. The researchers identified 7.7 million genes and identified a large number of known and unknown bacteria. The results showed clear country dependent differences, reflecting differences in farm systems and antibiotics supplementation. The results further illustrate how age, gender, and pig genetics are associated with differences in the composition of bacteria in the gut. The results show the impact of prohibition of the use of antibiotics as growth promoters in Denmark and France , as it seems to have reduced the load of antibiotics resistance genes in the French and Danish pigs, but some pigs in these countries harbor genes conferring resistance to a large number of antibiotics. The knowledge of the many genes in the gut bacteria will be of importance in order to use pigs as a model to elucidate the role of bacteria in relation to many human diseases, but will also be an important tool in the quest towards more sustainable knowledge-based pig farming with the need to combine feed efficiency with resistance to disease, while reducing the use of antibiotics, a main concern in relation to risks of multi-drug resistance in humans and animals.