Nutritive Evaluation of Two Legumes (Strophostyles) Supplemented to Goats Fed a High Quality Coastal Bermudagrass (Cynodon dactylon) Hay Diet

The objective of this study was to compare effects of supplementing coastal bermudagrass ( Cynodon dactylon ; CBG) hay with Strophostyles helvula (98 g crude protein (CP)/kg dry matter (DM), 476 g neutral detergent fiber organic matter basis (NDFOM)/kg DM, S. leiosperma (117 g CP/kg DM, 497 g NDFOM /kg DM), or cottonseed meal (506 g CP/kg DM, 352 g NDFOM /kg DM; CSM) on intake of CBG hay (127 g CP /kg DM, 691 g NDFOM /kg DM) and apparent digestibility of dietary DM, organic matter (OM), NDFOM, and CP by goats.  Six Boer × Spanish cross wethers (46.22 ± 3.99 kg) were fed CBG plus S. helvula , S.  leiosperma , or CSM at 122 or 216 g/kg DM intake in a 6 × 6 Latin square with 3 × 2 factorial arrangement of treatments.  There were no ( P = 0.53) supplement type × amount interactions.  Intake of DM, OM, and NDFOM of CBG was unaffected ( P = 0.33) by supplementation with CSM, S. helvula , and S. leiosperma.  Although intake of CBG was not affected, total diet NDFOM intake was 10.5% less ( P = 0.01) when CSM and S. helvula were supplemented than when S. leiosperma was used.  Supplement type did not affect ( P = 0.21) OM digestibility, but OM digestibility increased ( P = 0.05) 6.4% at the 216 versus 122 g/kg DM level of supplementation with the legumes or CSM.  Supplementation with CSM and S. leiosperma improved ( P = 0.02) NDFOM digestibility 7% versus supplementation with S. helvula .  As supplement amount increased NDFOM digestibility increased ( P = 0.02) by 5.5%.  The diet supplemented with CSM had the greatest CP digestibility, and S. helvula CP was 6% less digestible ( P = 0.02) than S. leiosperma .  As supplement amount increased, CP digestibility increased ( P = 0.01) 7%.  Considering digestibility and intake, CSM and S. leiosperma were the best supplements fed in this experiment.  Strophostyles leiosperma is recommended as a forage supplementation for goats when CBG hay basal diet is fed.