Phenotypic determination methods and research progress onimportant lactation traits in agricultural ruminants

As important economic traits of agricultural ruminants, lactation traits have a large number of phenotypic determination indices, and the identification methods of these indices are varied and complex. This study reviews the methods for determining the important lactation traits in agricultural ruminants of China to breed and improve the dairy animal germplasm resources with Chinese characteristics and to create new gene resources with excellent milk yield and quality. This review details the determination methods and research progress on the main lactation traits in the following four aspects: determination indices and methods of conventional lactation traits and unique milk composition traits, mid-infrared spectroscopy, and a brief introduction of the characteristic dairy species.