Performance and Feeding Behavior of Holstein and Holstein × Gyr Crossbred Heifers Grazing Temperate Forages

Abstract

This study aimed to investigate the difference between Holstein and Holstein x Gyr breeds on feeding behavior and performance of heifers grazing temperate pasture. The experiment was carried out in 89 days, split into 14 days of adaptation and 3 periods of 25 days. Two treatments were used: Holstein (HOL; n = 7) and Holstein × Gyr (HG; n = 7). Heifers grazed a consortium of ryegrass and Bristle Oats and were supplemented individually daily with corn meal at 0.33% of body weight plus 5 kg/d of corn silage. For 3 consecutive days, feeding behavior was observed for individual animals from direct visual observation recording at 10 min intervals. The digestibility trial was performed on d16 to d24 of each period. Body measurements and weight were taken at d0 and at d23, 24, and 25 of each period. Grazing duration, grazing frequency, and bite rate were greater for HOL than HG. Rumination characteristics, intake, digestibility, body measurements were not affected by breed. Breeds had differences in grazing characteristics, but it did not influence performance or intake parameters. Therefore, HOL and HG heifers managed under temperate pasture in tropical countries have similar performance.