Three experiments tested the effects of feeding CaO as part of the TMR or as CaO-treated corn stover (CS) on growth performance, carcass characteristics, and ruminal metabolism of cattle. In Exp. 1, steers (n = 162) were fed 1 of 3 diets containing 20% CS and 40% modified wet distillers grains with solubles: untreated CS (UCS), treated CS with 5% CaO (DM basis; TCS), and dietary inclusion of 1% CaO (DM basis; DC). Feeding DC or TCS decreased (P < 0.05) DMI, final BW, HCW, and back fat compared with feeding UCS. Feeding TCS decreased (P < 0.05) ADG compared with feeding UCS. In Exp. 2, heifers (n = 138) were fed 1 of 3 diets: UCS, TCS, and 40% corn silage (DM basis; SIL). Feeding TCS decreased (P = 0.05) DMI, and final BW, and back fat compared with feeding UCS and SIL. Heifers fed UCS had similar (P = 0.05) ADG, DMI, and marbling score as heifers fed SIL; however, final BW and G:F were decreased (P = 0.05). In Exp. 3, steers (n = 5) were fed in a 5 × 5 Latin square; diets were UCS, TCS, DC, SIL, and a control of 50% cracked corn. Feeding TCS tended to decrease (P = 0.06) ruminal pH when compared with UCS. Steers fed UCS had the least (P = 0.05) DM digestibility and steers fed the control had the greatest. Treating CS with CaO effectively increased digestibility; however, it did not improve cattle performance. Feeding cattle untreated, ensiled CS resulted in ADG and G:F comparable to feeding corn silage.
All Science Journal Classification (ASJC) codes
- Food Science
- Animal Science and Zoology