The effects of physical forms of corn and forage source on growth performance, blood parameters and ruminal fermentation of Holstein calves

Abstract

This investigation's purpose was the evaluation of the effects of physical forms of corn and forage sources on growth performance, blood parameters, and ruminal fermentation of Holstein calves. Forty-eight Holstein calves (38.2 ± 1.2 kg of BW) were used in a completely randomized design with 4 treatments and 12 replications for 65 days. The treatments were: 1) Basal diet + mashed form corn + wheat straw (MCWS), 2) Basal diet + flacked form corn + wheat straw (FCWS), 3) Basal diet + mashed form corn+ Sugarcane bagasse (MCSB) and 4) Basal diet + flacked form corn + sugarcane bagasse (FCSB). Final body weight and daily weight gain were affected significantly by the forage (F) factor whereas no effect from C (corn physical forms) and C×F interaction were observed. Skeletal growth parameters were not affected by C, F, and F×C factors. The trial factors did not affect triglyceride and BHBA levels, while glucose level and urea were affected by C and F factors. At 30 and 60 days, Calves fed on FCWS had the highest glucose. Also, calves fed the FCSB diet presented higher urea at 30 and 60 days. Acetate acid was affected significantly by C, F, and C×F interaction (P<0.05). Calves fed the MCWS diet had the maximum concentration of acetate acid. At 30 days, propionate acid was affected by C, F, and C×F interaction (P<0.05). Valeric acid was affected by C and F effect at 30 days. While for valeric acid no differences were observed at 60 days.