Agriculture & Food, Volume 6, 2018

Rezumat: The objective of this study was to investigate the effects of different early weaning programs on the performance, and its influence on skeleton growth and blood parameters of dairy calves. To meet this objective, 30 Holstein calves with initial body weight of 36 ± 8 kg were randomly assigned at birth to be weaned. Experimental treatments were: 1) Starter diet and whole milk from birth to 45 days (45 weaning day (WD), 2) starter diet and whole milk from birth to 65 days (65 WD), 3) starter diet and whole milk from birth to 90 days (90 WD). Starter diet and water were available adlibitum throughout the experiment. Dry matter intake (DMI) of daily starter and average daily gain (ADG) were measured until d 90 of life. Body weight (BW), body length, heart girth and withers height was measured at birth, 30, 60 and 90 day. Blood samples were collected from all calves at the end of the trail. BW and DMI in all measured periods (0, 30, 60 and 90 d) did not differ between treatments. Although 45 WD calves had higher ADG in 30 to 60 d than 65 WD and 85 WD calves. Consequently, in the overall period (d 0-90) greater ADG values were recorded for 45 WD calves. In the overall period, feed conversation ratio (FCR) affected by treatment and lowest values were recorded in 45 WD calves. Body measurements of calves did not differ among treatments at d 30, 60 and 90. Plasma concentration of cholesterol was lower in the 45 WD calves than in the 65 WD and 85 WD animals during the study. Under the conditions of this study, the results suggest that 45WD calves were more efficient at utilizing DMI for BW gain and growth.