Effect of administering energy supplement in feed on body condition and performance of high-yield dairy cows

Abstract

The objective of the investigations presented in this work was to establish the effects of a glycerol-based energy supplement in the diet of high-yield dairy cows on their body condition and production results during the early stage of lactation. Forty-seven cows were selected before calving, and they were divided into two groups: controls (n=26) and experimental (n=21). Cows of the experimental group were administered the preparation 'Energy Top' (Biochem GMBH, Germany), in a quantity of 250 ml daily during the final two weeks of the dry period and until the 60th day of lactation. The body condition score (BCS) of all cows was determined 10 days before calving, and on days 15 and 60 after calving. Blood samples were taken 10 days before and 15 days after calving, and concentrations of glucose and beta hydroxi-butyric acid (BHBA) were determined in all samples. Average daily milk production of all cows was measured on days 30 and 60 of lactation. The results showed that the differences in BCS between the dry period and puerperium, or the dry period and the 60th day of lactation, were within physiological values in the experimental group of cows, and higher than physiological values in the control group. Glucose concentration was statistically significantly higher in the experimental group than in the control group of cows 10 days before calving (p<0.05) and 15 days after calving (p<0.01). Fifteen days after calving, the BHBA concentration in the control group of cows was significantly higher (p<0.01) than in the experimental group. On days 30 and 60 of lactation, the milk yield of experimental cows was higher than of those in the control group, but the difference was not statistically significant. The obtained results indicate that energy supplements should be used as an integral part of the feed ration during the peripartal period in order to prevent changes in the body condition score of cows by more than 0.7 points, and also that, in cows with a daily milk production of up to 30 l, an energy supplement has a stimulatory effect on milk production until the establishing of an energy balance, in this case, until around the 30th day following calving. .