Betaine is a kind of natural compound,widely exists in plans and animals.As a feed additive,it can be supplemented to feed in variety of purposes.

Effects of betaine on nutrient digestibility of ileum or whole digestive tract in pigs. Repeated observations of increased fibre digestibility in the ileum suggest that betaine has stimulated bacterial fermentation in the small intestine because intestinal cells do not produce fibre degrading enzymes.The portion of plan fibre contains nutrition,which can be released during the process of microbial fiber degradation.Thus the digestibility of dry matter and crude ash were also improved.Adding betaine in pig’s dietary can reduce the animals' maintenance energy requirements.It is hypothesized that when betaine can maintain intracellular osmotic pressure, the need for ion pumping is reduced, which is an energy-demanding process.Under of the limited of energy intake,the replenishment effect of betaine will be more obvious by increasing the energy required for growth rather than maintenance. 

Betaine can prevent the cell from osmotic press,when betaine concentration was observed in different tissues, intestinal tissue contained quite high levels of betaine.Besides,betaine has good effects on the balance of cells and multiplication capacity. Therefore, the researchers found that the up-going betaine levels in piglets increased duodenal villi height and ileum fossa depth, and the villi were more uniform.The effect of betaine on the intestinal health of weaned piglets is to decrease the diarrhea rate.The experiment showed that adding 50 g betaine in 1 kg pig feed reduced the diarrhea rate and morbidity of weaned piglets.