Abstract

Background:
Resource optimization through precision nutrition management is a critical tool for the decarbonization of the dairy sector in the context of the increasing drive toward climate neutrality by 2050.

Aim:
This study was conducted as a before-after intervention field study to examine the impact of a precision automated compound feed production system on production performance and urea levels in milk in dairy cows.

Methods:
The intervention was implemented on a commercial dairy farm in Central Bulgaria (220 Bulgarian Black and White cows; average productivity 8,500–9,000 kg per lactation). A monitored subgroup of 80 cows at 60–150 days in milk (free-range group on deep litter; mean parity 1.8 ± 0.7; body weight 594 ± 38 kg) received the same total mixed ration throughout the study. The conventional compound-feed preparation was replaced by an automated precision installation, and paired 28-day monitoring periods before and after the switch were used for comparison.

Results:
After the transition, the CV of the compound feed fell below 5.0%, indicating optimal homogeneity. Under this condition, milk urea was stabilized at 27.14 mg/dL, compared with 30.22 mg/dL at lower mixing precision. Across the intervention, the average milk urea decreased from 30.01 to 25.94 mg/dL (P < 0.01; Cohen's d = 2.12), whereas the average daily milk yield increased from 28.09 ± 0.36 to 31.57 ± 0.14 kg per cow (P < 0.001; Cohen's d = 2.42).

Conclusion:
Precision automated compound-feed production improved ration homogeneity, reduced milk urea, and increased milk yield, supporting resource optimization for the decarbonization of the dairy sector.

Key words: Compound feed; Dairy cows; Milk yield; Precision automated production; Urea.