The effects of a high- or low-plane of nutrition pre-weaning on growth and starter intake of group-housed calves

Abstract Text: The objective was to determine the effects of plane of nutrition, when fed through an automated calf feeder, on starter intake and growth of group-housed calves. Twenty-six female Holstein calves were fed 8L of colostrum in the first 36 h of life before being offered pasteurized whole milk and randomly assigned to either a HIGH (10L/d; n=12) or LOW (5L/d; n=14) plane of nutrition. All calves were allowed 2.5L of milk per meal until d 48 when a 10-d weaning transition began, where milk was reduced by 10% per day, resulting in all calves being weaned at d 58. Calf starter and water were provided ad libitum starting on d 3.  Calves were housed in individual pens for the first 21 ± 3 d and fed using the Calf Rail system (Förster-Technik, Germany) before moving to a group pen where they were fed through an automated calf feeder. Individual starter intake was measured via an automated system on a daily basis from d 25 to 70, and body weights (BW) were measured weekly from birth to d 70. Blood samples were taken in the first week of life and with no differences observed in serum protein (5.3±0.32 vs. 5.3±0.32 mg/dL; P = 0.95) or immunoglobin concentration (17.67±1.80 vs. 15.35±1.80 g/L; P = 0.37). Birthweight of calves was not different between the treatment groups (40±1.25 vs. 42±1.25 kg; P = 0.27) however BW at d 70 was greater for HIGH than LOW calves (113.5±2.03 vs. 100.11±2.03 kg; P < 0.01). Pre-weaning average daily gain was greater for HIGH than LOW (0.90±0.03 vs. 0.65±0.03 kg/d; P <0.01), however no difference was seen post-weaning (1.30±0.06 vs. 1.29±0.06 kg/d; P = 0.96). Prior to the weaning transition (d 42-48) starter intake (g/d) was greater in calves on the LOW than HIGH plane of nutrition (591±89 vs. 1273±93, P < 0.01, respectively). Starter intake over the 10-d weaning transition tended to be greater for LOW than HIGH calves (1490±112 vs. 1181±116; P = 0.07), however post-weaning no difference was seen between treatments (2723±200 vs. 3188±200; P = 0.11). Results indicate that feeding more milk pre-weaning may suppress starter intake, however, the effect is not carried post-weaning and does not compromise growth.

Keywords: feeding system, group housing, starter intake