Effect of weaning weight on growth performance, feed efficiency, and behavioral characteristics of Holstein-Friesian and Brown Swiss calves.

Background: Farm profitability depends on raising healthy calves, which rests on successful feeding and management programs. Objective: To determine the effects of weaning weight on growth performance, feed efficiency, behavioral traits, as well as feeding cost of Holstein-Friesian and Brown Swiss calves. Methods: Sixty-seven newborn dairy calves were allocated into four weaning-weight groups [60 kg (n=18), 65 kg (n=19), 70 kg (n=18) and 75 kg (n=12)]. Body weights (BW) and measurements were recorded at birth, weaning, and four months of age. An instantaneous sampling method was used to collect behavioral data. Results: Daily weight gain of Brown Swiss calves was higher than Holsteins between weaning and four months of age (p<0.05). During pre-weaning, daily weight gain of calves weaned at 60 kg was lower than the other three groups (p<0.05). Feed efficiency of Holstein-Friesian was higher than Brown Swiss calves in the period between birth and four months of age (p<0.05). Chest depth of calves weaned at 60 kg was (p<0.05) lower compared to the other groups. Water drinking behavior during the pre-weaning period was notably higher in calves weaned at 75 kg (p<0.05). Conclusions: Our results suggest that dairy calves can be weaned at 60 kg of BW without detrimental effects on performance, and their feed cost per kg weight gain is significantly lower compared to higher weaning weights. [ABSTRACT FROM AUTHOR]