Effect of feeding rate of milk replacer with early weaning and protocols for water treatment and sanitation on dairy calf growth and health

Forty-eight Holstein calves (12 per treatment) were fed 2 rates of the milk replacer (MR; 27% CP, 17% fat powder) with 2 water treatment and sanitation protocols. The protocols were 0 (using 500 mg/L sodium hyperchlorite wash water) or 5 mg/L of chlorine dioxide (using 50 mg/L chlorine dioxide wash water). The MR rates were either 0.66 kg (MOD) or up to 1.1 kg (HI) of DM daily divided into 2 equal meals fed at 0630 and 1600 h daily. Calves fed MOD received 0.66 kg of DM from d 1 to 25, then 0.33 kg of DM in only the a.m. feeding from d 26 to 28. Calves fed HI received 0.79 kg of DM from d 1 to 7, 1.1 kg of DM from d 8 to 21, 0.66 kg of DM from d 22 to 25, and 0.33 kg of DM in the a.m. only from d 26 to 28. Free−choice starter (20% CP) and water was fed from d 1 to 56. Calves were initially 2 to 4 d of age and 47 ± 1.2 kg. The 2 MR rates and 2 water treatments were analyzed as a 2 × 2 factorial arrangement in a completely randomized design with repeated measures. Cryptosporidium was the predominate organism found in the fecal samples. There was no effect of sanitation protocol on performance or health of calves. Calves fed HI MR had 18% greater ADG and more medical days over the 56-d trial than calves fed MOD MR, whereas there was no difference in hip width change.