TY - JOUR
T1 - Influence of forbs and shrubs on nutrient digestion and balance in sheep fed grass hay
AU - Rafique, S.
AU - Wallace, J. D.
AU - Holechek, J. L.
AU - Galyean, M. L.
AU - Arthun, D. P.
PY - 1992/3
Y1 - 1992/3
N2 - Eight Debouillet yearling wethers were used in a replicated 4 × 4 Latin square experiment to evaluate the influence of forb mix, a shrub mix and alfalfa (ALF) hay on nutrient utilization of a basal grass hay (GH; 1.21% N) diet. Wethers ate less (P<0.05) of the forb diet than ALF or shrub diets, presumably because forb acceptance was substantially reduced when fed in a dried, ground form. Addition of ALF, forbs or shrubs to GH did not affect (P>0.05) digestibility of dry matter, gross energy, or neutral detergent fiber but ADF digestibility was less (P<0.05) for wethers fed forbs or shrubs than for those fed GH or GH+ALF. Addition of ALF or shrubs to the basal GH increased (P<0.05) N and gross energy intakes. When adjusted to a common N intake level by covariate analysis, fecal N was less (P<0.05) and urine N losses were greater (P<0.05) for the shrub diet compared with GH alone or GH+forbs, but N retention was similar (P>0.05) among all diets. Metabolizable energy (ME) values for diets in this experiment (1.23-1.45 kcal/g) were somewhat lower than those reported previously (1.6-1.9 kcal/g) for GH diets. Forb and ALF diets did not differ (P>0.05) in ME content (1.45 and 1.40 kcal/g) and both were greater (P<0.05) than the GH or GH+shrub diets (1.23 and 1.27 kcal/g). Based on these results, forbs and shrubs influence digestibility of most nutrients in GH in a manner similar to ALF. We conclude that shrubs and forbs used in this study can effectively serve as supplements for low-quality GH diets for livestock. Shrubs may have greater potential for improving efficiency of N utilization, whereas forb additions may potentially increase energy retention with GH diets.
AB - Eight Debouillet yearling wethers were used in a replicated 4 × 4 Latin square experiment to evaluate the influence of forb mix, a shrub mix and alfalfa (ALF) hay on nutrient utilization of a basal grass hay (GH; 1.21% N) diet. Wethers ate less (P<0.05) of the forb diet than ALF or shrub diets, presumably because forb acceptance was substantially reduced when fed in a dried, ground form. Addition of ALF, forbs or shrubs to GH did not affect (P>0.05) digestibility of dry matter, gross energy, or neutral detergent fiber but ADF digestibility was less (P<0.05) for wethers fed forbs or shrubs than for those fed GH or GH+ALF. Addition of ALF or shrubs to the basal GH increased (P<0.05) N and gross energy intakes. When adjusted to a common N intake level by covariate analysis, fecal N was less (P<0.05) and urine N losses were greater (P<0.05) for the shrub diet compared with GH alone or GH+forbs, but N retention was similar (P>0.05) among all diets. Metabolizable energy (ME) values for diets in this experiment (1.23-1.45 kcal/g) were somewhat lower than those reported previously (1.6-1.9 kcal/g) for GH diets. Forb and ALF diets did not differ (P>0.05) in ME content (1.45 and 1.40 kcal/g) and both were greater (P<0.05) than the GH or GH+shrub diets (1.23 and 1.27 kcal/g). Based on these results, forbs and shrubs influence digestibility of most nutrients in GH in a manner similar to ALF. We conclude that shrubs and forbs used in this study can effectively serve as supplements for low-quality GH diets for livestock. Shrubs may have greater potential for improving efficiency of N utilization, whereas forb additions may potentially increase energy retention with GH diets.
UR - http://www.scopus.com/inward/record.url?scp=38249014305&partnerID=8YFLogxK
U2 - 10.1016/0921-4488(92)90201-E
DO - 10.1016/0921-4488(92)90201-E
M3 - Article
AN - SCOPUS:38249014305
VL - 7
SP - 113
EP - 122
JO - Small Ruminant Research
JF - Small Ruminant Research
SN - 0921-4488
IS - 2
ER -