Nutritional efficiency of feed-restricted F1 Holstein/Zebu cows during the middle third of lactation

The objective of this study was to evaluate the effects of different levels of quantitative feed restriction on nutrient intake and digestibility, nitrogen balance, efficiency and feeding behavior, and productive performance in F1 Holstein/Zebu cows during the middle third of their lactation. Sixty F1 Holstein/Zebu cows with 111.5 ± 11.75 days of lactation and an initial body weight (BW) of 499 ± 30 kg (mean ± SEM) were used. The experimental design was completely randomized with the following diet levels of feed restriction: 3.39%, 2.75%, 2.50%, 2.25% and 2.00% of BW, with 12 replications for each level.The experiment lasted for 63 days, of which each period lasted 21 days with the first 16 days for diet adaptation followed by 5 days for collection of data and samples. For each 1% of BW diet restriction, there was a decrease in dry matter intake of 5.26 kg/day (p