Fig. 4

Effect of age at first forage consumption on daily rumination time during the calf, top-dressing and TMR feeding periods. Asterisks (*) indicate differences (P ≤ 0.05) between groups (weeks 10: CON < LHAY; weeks 11 and 12: CON < EHAY, MHAY and LHAY). Error bars represent ± SE. CON = Calves were fed starter concentrate without forage from d 1 to 84, HAY = Starter concentrate and forage were fed to calves as a free choice way from d 1 to 84, EHAY = calves began to consume forage at the earliest (from d 4 to 6), MHAY = calves began to consume the forage from d 7 to 9, LHAY = calves began to consume forage at latest (from d 10 to 15). Calves were housed in individual hutches from d 1 to 84 (weeks 1 to 12) and then transferred to a barn and fed calf starter top-dressed with hay (TDR, from d 85 to 133, week 13 to 19) and total mixed ration later (TMR, from d 134 to 196, week 20 to 28)