Pregnancy success represents a major issue for the economic income of cattle breeders. Early detection of pregnant and non-pregnant animals, as well as the prediction of early pregnancy failure, can influence farm management decisions. Several diagnostic tools for pregnancy are currently available. Among these, pregnancy-associated glycoproteins (PAGs) have been shown to be useful for identifying the presence of vital embryos and for pregnancy follow-up monitoring. This review presents an overview of the PAGs\' functions, their pregnancy trends, and their use as a tool to improve reproductive management in bovine and other dairy livestock, such as small ruminants and buffalos.

A2 milk is an easily digestible product since it has only A2 beta-casein. In cattle, the A1 and A2 alleles are found in the population and the A2 milk is produced from A2A2 animals. Little is known about these alleles in other domestic dairy species. The present study aims to analyze sequence of genetic material available on public databases and quantify the animals genotyped. Eight domestic species were analyzed. There is strong evidence that domestic non-bovine species only carry A2 beta-casein. The data reported here for goats already confirm it due to the large number of animals genotyped as well as buffaloes. It means that they naturally produce A2 milk and no selection must be done. Thus, the fact that A2 milk is easier to digest can be used to add value to dairy product of these species. It helps to conquer new markets. It also improves people\'s health and breeder profitability.