| Autor: |
Caton, J. S., Williams, J. E., May, T., Beaver, E. E., Belyea, R. L. |
| Zdroj: |
Journal of Animal Science; August 1991, Vol. 69 Issue: 8 p3406-3415, 10p |
| Abstrakt: |
Twelve ruminally, duodenally, and ileally cannulated (average initial BW 313 ± 20 kg) and 27 intact Hereford heifers (average initial BW 256 ± 17 kg) were used in two experiments to evaluate dairy food wash water solids (WWS) as a protein source in medium-quality hay diets. Heifers received a basal diet of orchardgrass hay (7.4% CP) and were assigned to one of three supplement treatments: control (C; .9% CP), WWS (18.8% CP)-, and soybean meal (SBM; 19.1% CP)-based supplements (fed at 1.5 kg of DM/d). Supplements were formulated to have similar ME concentrations. Ruminal ammonia concentrations were greater (P< .10) for WWS- and SBM-supplemented heifers than for C heifers at most sampling times. Moreover, WWS and SBM increased (P< .10) total VFA (mM) and acetate (mol/100 mol) and lowered propionate (mol/100 mol) at several sampling times. Ruminal fluid volume (liters) was unchanged (P> .10) by treatment; however, fluid dilution and flow rate (liters/h) were less (P< .10) in C heifers than in heifers fed SBM or WWS supplements. Wash water solids and SBM supplementation increased (P< .10) OM, NDF, and ADF digestibilities compared with C heifers. Feeding WWS and SBM supplements increased BW at 84 d (P< .10) compared with C-supplemented heifers. Forage intake at 54 and 84 d by heifers supplemented with SBM or WWS was greater (P< .10) than by C heifers. Control-supplemented heifers had the least, WWS intermediate, and SBM the greatest ADG at 84 d (P< .10; .14 vs .35 vs .48 kg/d, respectively). These data indicate that WWS may be used as a protein source without serious adverse effects in heifers consuming medium-quality hay for 84 d. |
| Databáze: |
Supplemental Index |
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