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Performance impacts of feeding bermudagrass (Cynodon dactylon) or ryegrass (Lolium multiflorum) plus rye (Secale cereale) baleage to weaned crossbred beef calves

Tuesday, July 22, 2014: 2:30 PM
2104B (Kansas City Convention Center)
Rachel M Martin , Louisiana State Univeristy, Baton Rouge, LA
Ryon Walker , LSU AgCenter, Hill Farm Research Station, Homer, LA
Brad Buttrey , LSU AgCenter, Hill Farm Research Station, Homer, LA
Cathleen C. Williams , LSU AgCenter, Baton Rouge, LA
Abstract Text: Two hundred forty Angus and Angus x Charolais cross calves (BW = 217 ± 20.6 kg) were used to evaluate performance and ruminal pH from feeding bermudagrass (Cynodon dactylon) or ryegrass (Lolium multiflorum) and rye (Secale cereale) baleage in hay rings. Calves were stratified by BW, age, sex, and breed and assigned to one of 12 paddocks (0.40 ha each) with four treatment diets and fed for a 7 d adaption and 60 d backgrounding period. Diets included: early boot stage bermudagrass harvested for hay, CP = 8.2%, TDN = 59.9%, and DM = 88.8%, (BERH); early boot stage ryegrass and rye harvested for baleage, CP = 12.8%, TDN = 64.5%, and DM = 37.2%, (ERRG); bloom stage ryegrass and rye harvested for baleage, CP = 9.2%, TDN = 62.7%, and DM = 55.7%, (LRRG); and early boot stage bermudagrass harvested for baleage, CP = 9.2%, TDN = 57.4%, and DM = 49.1%, (BERB). Calves on BERH, LRRG, and BERB had free choice access to a 34% CP (as fed basis) liquid protein supplement. Two-day BWs were collected on d -1, 0, 29, 30, 59, and 60 for comparison of BW, BW gain, and ADG. Ruminal pH was measured from randomly selected calves (n = 5/paddock) on d 0, 30, and 60. There was a treatment by day interaction (P < 0.01) for BW and ruminal pH. Initial BW was similar among treatments (P > 0.05). Calf BW was heavier (P < 0.05) for LRRG compared with BERB and BERH, and heavier (P = 0.01) for ERRG compared with BERB on d 60, respectively. Body weight gain and ADG were greater (P < 0.01) for calves fed LRRG (34.6 ± 1.2 kg and 0.58 ± 0.02 kg) compared with calves fed ERRG (27.9 ± 1.2 kg and 0.46 ± 0.02 kg), BERH (22.2 ± 1.2 kg and 0.37 ± 0.02 kg), and BERB (19.2 ± 1.2 kg and 0.32 ± 0.02 kg). BW gain and ADG were greater (P < 0.01) for ERRG compared with BERB and BERH, but similar among BERB and BERH, respectively. There was a treatment effect for ruminal pH where ERRG calves had higher (P< 0.01) pH compared with LRRG, BERH, and BERB calves. Performance of backgrounded calves fed ryegrass and rye baleage with or without supplementation, based on harvest stage, was improved over feeding bermudagrass hay with supplementation.

Keywords: beef cattle, backgrounding, baleage