Effects Of Different Energy Diets Before Prepartum Period On Postpartum Production And Diseases Of Dairy Cows

With the increase of per unit yield of dairy cows,the incidence of metabolic diseases of dairy cows is also gradually increasing,in which the elimination rate of some dairy farms is as high as30% due to negative energy balance caused by energy metabolic disorders,reproductive disorders and postpartum diseases.A large number of previous studies have proved that pre-perinatal dietary energy is closely related to the occurrence of postpartum disease.therefore,this experiment was conducted to study the effects of different pre-perinatal energy diets on postpartum performance and disease incidence of dairy cows.In this experiment,160 dairy cows from A and B farms with similar body condition and parity were divided into An and B groups.Group A was fed with low-energy diet and group B was fed with high-energy diet.The experiments of the two groups of dairy cows were carried out on the 21 st day before delivery,and the dry matter intake,body condition score,body weight,blood biochemical indexes and some hormone levels,milk yield,milk composition,postpartum morbidity and treatment were recorded up to 28 days after delivery.The results showed that: 1.Feeding low-energy diets in the pre-perinatal period could speed up the recovery of dairy cows after delivery and reduce weight loss compared with standard diets.2.The close fed with different energy diets in the pre-perinatal period showed differences in postpartum milk production.The low-energy group was higher than the standard-energy group,but there was no significant difference in the milk composition of the two.3.The changed in blood biochemical indexes of dairy cows fed with low-energy diets in the pre-perinatal period tended to be more stable than those of standard diets.The experiment found that there was no significant difference in the blood glucose concentration of dairy cows fed with different energy diets before and after parturition in the prenatal period;the blood insulin and glucagon concentration of the standard diet group was higher than that of the low energy diet group before delivery.After delivery,it was lower than that of the low-energy diet group;the non-esterified fatty acid concentration had the opposite trend;the β-hydroxybutyric acid concentration of the standard diet group was always higher than that of the low diet group.4.Compared with standard diets,feeding low-energy diets in the pre-perinatal period could reduce the incidence of postpartum metabolic diseases and shorten the treatment period.The experiment found that the incidence of hypocalcemia,displaced abomasum after delivery in dairy cows fed with different energy diets in the pre-perinatal period was low and there was no significant difference,but the incidence of placenta,metritis,and ketosis was the standard day.The diet group was higher than the low-energy diet group.Cows fed with different energy diets in the pre-perinatal period had significant differences in the cure rate of the disease after delivery.The treatment period of the low-energy diet group was significantly shorter than that of the standard diet group.The results of this experiment showed that feeding low-energy diets in the pre-perinatal period not only reduced the negative energy balance of dairy cows after delivery,but also speeded up the recovery of dairy cow performance,and reduced the incidence of postpartum diseases in dairy cows,and shortens the cow’s treatment cycle.Therefore,it was recommended that dairy cows be fed low-energy diets during the pre-perinatal period.