Reproductive loss in high-producing dairy cattle: where will it end?

摘要: The dairy industry in the United States has changed dramatically last decade. Milk production per cow increased steadily because of a combination improved management, better nutrition, and intense genetic selection. Dairy farms are larger, nearly 30% cows on with 500 or more cows. shift toward productive larger herds is associated decrease reproductive efficiency. Cows greatest milk have highest incidence infertility, but epidemiological studies suggest that, addition to production, other factors probably decreasing efficiency our herds. physiology over past 50 yr, physiological adaptations high may explain part decline. Critical areas for new research include control estrous cycle, metabolic effects lactation reproduction, mechanisms linking disease early embryonic mortality. Solving loss will not be easy only small number groups study reproduction postpartum Therefore, present base need expanded. For this occur, funding must above its current level renewed emphasis placed solving emerging crisis infertility