Effect Of Different DCAD And Calcium Levels Of Diet In Early Perinatal Period On Performance And Calcium Metabolism In Dairy Cow

The effect of different DCAD values and dietary calcium levels in the early perinatal period on the performance and calcium metabolism in dairy cow was researched, in order to further explore the influence of feeding anionic salt in the early perinatal period on the performance and the control of blood calcium concentration, and whether there had a positive effect of adding calcium to the basis of anion salt on the performance and the serum calcium concentration. Aim was to provide the theoretical basis to the promotion of anionic diet and the adjunction of calcium in the early perinatal period of cow.24 of Chinese Holstein with body weight of around 550kg, 2-5 parity, body condition score of 3.5 in the late dry milk period were selected, averagely divided into 3 groups according to the principle of matching experimental design, and respectively offered the basal diet (the control group), anionic diet (group 1), high-calcium anionic diet (group 2) in 21 days of prenatal. After delivery, the experimental cows in each group were fed the same lactation diet , the end of feeding experiment was 60 days postpartum.Feeding anionic diet, high-calcium anionic diet to dairy cow in the early perinatal period, the dry matter intake of dietary was not significantly affected (P > 0.05). Anionic diet could significantly increase the daily milk yield in cows of postpartum (P < 0.05), significantly reduce the somatic cell count in milk (P < 0.01); Compare with anionic diet, high-calcium anionic diet had a trend to further increase the daily milk yield of postpartum (P > 0.05).Feeding anionic diet, high-calcium anionic diet to dairy cow in the early perinatal period, the urine pH value of cows were between 5.5-6.5. Anionic diet could significantly increase the total calcium content of urine in cows (P < 0.01), significantly reduce the total calcium content of fecal dry matter (P < 0.05); Compare with anionic diet, high-calcium anionic diet could significantly reduce the total calcium content of urine in cows 14 days prenatal (P < 0.01), not significant affect the total calcium content of fecal dry matter in 24h after birth (P > 0.05).Anionic diet could significantly increase the concentration of parathyroid hormone in serum of cows (P < 0.05), significantly increase the concentration of vitamin D3 in serum (P < 0.01), significantly reduce the concentration of calcitonin in serum ( P < 0.05), and significantly increase the concentration of calcium in serum after delivery (P < 0.01). Compare with anionic diet, high-calcium anionic diet could significantly increase the concentration of parathyroid hormone in serum of cows (P < 0.01), significantly reduced the concentration of vitamin D3 in serum (P < 0.05), significantly increase the concentration of calcitonin in serum (P < 0.05), significantly increase the concentration of calcium in serum of cows (P <0.01).