In this study, nutritional data on the four major kinds of infant products for special medical purposes produced in China and some other countries were collected and compared for differences in the three calorigenic nutrients, vitamins, minerals, and mandatory or optional nutrients. Moreover, principal component analysis (PCA) was carried out on these data. The results showed that the domestic brands of amino acid-based or hypoallergenic infant formula were significantly richer in fat, vitamin K, pantothenic acid, and taurine than the imported brands (P < 0.05), but had a significantly lower content of folic acid (P < 0.05). The contents of fat, manganese, taurine, and carnitine in the domestic brands of partially hydrolyzed milk infant formula were significantly higher than those in the imported brands (P < 0.05). The contents of iron, vitamin D, and vitamin B2 in the domestic brands of lactose-free or low-lactose infant formula were significantly higher than those in the imported brands (P < 0.05). Notwithstanding, no significant differences in any of the tested nutrients were observed between the domestic and imported brands of infant formula for low birth weight infants and preterm infants. The results of PCA showed that the contents of manganese, VB5 and VB3 made the greatest contribution to the nutritional difference between the domestic and imported brands of amino acid-based or hypoallergenic infant formula, the contents of VB6, VB2, VB5 and VB3 made the greatest contribution to the nutritional difference between the domestic and imported brands of partially hydrolyzed milk infant formula, while the contents of VB5 and VB3 made the greatest contribution to the nutritional difference between the domestic and imported brands of lactose-free or low-lactose infant formula and of infant formula for low birth weight infants and preterm infants.

Probiotics are a class of active microorganisms that have a beneficial effect on the physiological functions of the host and are widely used in the fields of food, medicine and livestock husbandry. However, the mechanism of action of probiotics is still not fully understanding. In this paper, the use of probiotics as an alternative to antibiotics in disease treatment and as feed additives to improve the growth performance of livestock and poultry as well as its role in new functional foods is reviewed with the aim of providing further information for the development of probiotics.