418 Effects of maturity at harvest of Eragrostis tef (Moxie) on nutrient intake digestibility and omasal flow in beef cattle.

摘要

(‘Moxie’ teff) could be a viable alternative forage for beef cattle. However, there is limited information on ruminal and total tract nutrient digestibility when teff hay harvested at different stages of maturity is fed to cattle. Therefore, our objective was to determine the effects of feeding teff hay harvested at the boot (BT), early-heading (EH), or late-heading (LH) stages of maturity on nutrient intake, ruminal digestion, omasal flow, and apparent total tract digestion in beef cattle. Six ruminally cannulated beef heifers (mean initial BW ± SD, 476 ± 32.6) were used in a replicated 3 × 3 Latin square with 28-d periods (18 d for adaptation). Dietary treatments were BT, EH, or LH teff hay, and DMI was measured daily. Omasal digesta was collected (d 26 to 28) for measurement of ruminal digestion and omasal nutrient flow, as were fecal samples for apparent total tract nutrient digestibility determination. Data was analyzed using PROC MIXED in SAS. The NDF and ADF content of teff did not change ( ≥ 0.29) with advancing maturity. Diet also had no effect ( ≥ 0.14) on intake, ruminal digestion, omasal flow and apparent total tract digestion of DM, NDF, and ADF. Crude protein content decreased ( < 0.01) with advancing maturity (18.7, 14.7, and 11.9%, respectively). Crude protein intake was lower ( < 0.01) for heifers fed EH and LH than BT hay. Although there was no diet effect ( > 0.23) on ruminal digestion and omasal flow, total tract digestion of CP was ( < 0.01) lower for heifers fed LH than BT hay (83.3 vs. 78.3%). In summary, delaying harvest of teff hay had no effect on NDF and ADF intake, digestibility and omasal flow. However, delaying harvest resulted in a decreased in CP content, intake and apparent total tract digestion.