Abstract
This work sought to investigate the effects of different dosages of energy supplements (XE) on energy balance, dairy performance, and blood metabolites in Holstein Friesian cows. Ninety nursing Holstein Friesian cows were randomly distributed to three groups: Control (C), low dosage (0.1 kg/cow/day, XE1), and high dose (0.2 kg/cow/day, XE2). Over the course of one week, known as the acclimatization period, we gradually exposed the cows to the extra food. Using XE components glycerol and propylene glycol made via fermentation with single-cell protein, the treatment ran for eight weeks. Milk composition and its production, along with blood metabolites, were evaluate. The XE2 group significantly (P < 0.05) improved total digestible nutrients and net energy versus control group. Compared to other groups, cows in the XE2 group produced the most milk during the weeks; their relative increase from 29.5 L/day in week 1 to 31.5 L/day in week 8 is statistically significant (P < 0.05). Milk fat and protein notably (P < 0.05) increased in the high-dose group (XE2) by roughly 14% and 9%, respectively, versus control cows. Blood metabolites like beta-hydroxybutyrate, non-esterified fatty acids went down (P < 0.05), and urea nitrogen was nonsignificant, even though insulin and blood glucose levels went up, which means metabolic health and energy balance got better. Particularly in cows with outstanding production potential, the study found that introducing energy supplementation into dairy diets improved energy balance, milk yield, milk composition, and blood metabolites.