Graduate Student Final Report – Ceres Trust Research Grant
Graduate Student: Elizabeth Bjorklund, University of Minnesota West Central Research and Outreach Center at Morris
Major Professor: Bradley Heins, Ph.D., University of Minnesota West Central Research and Outreach Center at Morris
Heifer calves (n=124) were used to evaluate the effect of early life feeding duration in an organic group management system on growth and economics of organic dairy calves. Calves were assigned to replicate feeding groups of 10 in super hutches by birth order, and were born at the University of Minnesota West Central Research and Outreach Center, Morris, during 2011 and 2012. Breed groups of calves were: Holsteins (n=15) selected for high production (HO), Holsteins (n=23) maintained at 1964 breed average level (H64), crossbreds (n=54) including combinations HO, Montbéliarde, and Swedish Red, selected for high production (HMS), and crossbreds (n=32) including combinations of HO, Jersey, and Swedish Red selected for durability (HJS). Calves were weaned at 30 (EW), 60 (MW), or 90 (LW) days of age, and groups were fed 1.5% of birth weight of 13% total solids organic milk once daily and then weaned when the group consumption averaged 2 lb starter/calf/day. Calves were consuming about 11.5% of their birth weight in whole milk once per day. Body weight and hip height were recorded at birth, once per week, and at waning. Weaning group performance was weaning age (days), EW (47.6), MW (64.5), LW (93.7); gain per day (lb), EW (1.11), MW (1.40), LW (1.66); weaning weight (lb), EW (136.2), MW (174.7), LW (238.2); and weaning hip height (in), EW (35.3), MW (36.1), LW (38.1). The HO (1.52; 192.6), H64 (1.28; 173.0), HMS (1.44; 187.7), and HJS (1.32; 1.78.8) calves were different for gain per day (lb) and weaning weight (lb.), respectively. Total costs (grain and organic milk) to weaning per calf were $109.30 for EW, $187.13 for MW, and $295.68 for LW groups; however, the cost per pound of gain was significantly higher for the EW ($2.51) group than the MS ($2.09) or LW ($1.88) groups. Organic dairy producers should regularly evaluate their costs for organic milk and grain fed to calves, along with growth rates, to determine the optimum time to weaning for their operation.