PerForMance in Dairy cows
نویسنده
چکیده
• Blood growth hormone (GH) concentrations increase shortly after calving. • Greater blood GH coordinates nutrient partitioning; the process through which nutrients are preferentially targeted for milk production. Blood insulin and insulin-like growth factor (IGF)-I remain low when blood GH concentrations increase. • Blood GH concentrations are elevated in cows in negative energy balance. Blood insulin and IGF-I concentrations are low in cows in negative energy balance. • Postpartum dairy cows experience a variety of reproductive abnormalities. • Many of reproductive abnormalities can be linked to negative energy balance through hormonal mechanisms involving GH, IGF-I, and insulin.
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