Prepartum Intake, Postpartum Induction of Ketosis, and Periparturient Disorders Affect the Metabolic Status of Dairy Cows

摘要

Nutritional management during the dry period may affect susceptibility of cows to metabolic and infectious diseases during the periparturient period. Thirty-five multiparous Holstein cows were used to determine the effect of prepartum intake, postpartum induction of ke-tosis, and periparturient disorders on metabolic status. Cows were fed a diet from dry-off to parturition at either ad libitum intake or restricted intake [RI; 80% of calculated net energy for lactation (NE_L) requirement]. After parturition, all cows were fed a lactation diet. At 4 d in milk (DIM), cows underwent a physical examination and were classified as healthy or having at least one periparturient disorder (PD). Healthy cows were assigned to the control (n = 6) group or the ketosis induction (KI; n = 9) group. Cows with PD were assigned to the PD control (PDC; n = 17) group. Cows in the control and PDC groups were fed for ad libitum intake. Cows in the KI group were fed at 50% of their intake on 4 DIM from 5 to 14 DIM or until signs of clinical ketosis were observed; then, cows were returned to ad libitum intake. During the dry period, ad libitum cows ate more than RI cows; the difference in intake resulted in ad libitum cows that were in positive energy balance (142% of NE_L requirement) and RI cows that were in negative energy balance (85% of NE_L requirement). Prepartum intake resulted in changes in serum metabolites consistent with plane of nutrition and energy balance. Prepartum intake had no effect on postpartum intake, serum metabolites, or milk yield, but total lipid content of liver at 1 d postpartum was greater for ad libitum cows than for RI cows. The PD cows had lower intake and milk yield during the first 4 DIM than did healthy cows. During the ketosis induction period, KI cows had lower intake, milk yield, and serum glucose concentration but higher concentrations of nonesterified fatty acids and β-hydroxybutyrate in serum as well as total lipid and triacylglycerol in liver than did control cows. Cows with PD had only modest alterations in metabolic variables in blood and liver compared with healthy cows. The negative effects of PD and KI on metabolic status and milk yield were negligible by 42 DIM, although cows with PD had lower body condition score and BW. Prepartum intake did not affect postpartum metabolic status or milk yield. Periparturient disorders and induction of ketosis negatively affected metabolic status and milk yield during the first 14 DIM.