Method of feeding a liquid-protein supplement with low- to medium-quality hay affects hay waste and cow performance

Nonlactating Angus cross beef cows were used in 2 studies to evaluate method of supplementing a liquid protein with low- to medium-quality bermudagrass hay on waste and cow performance. In study 1, 191 cows were stratified by BW, BCS, and age and assigned to 1 of 6 pastures with 3 treatments for 77 d. Treatments included a liquid protein provided free choice (TNK), poured into bales at 10% of bale weight (POR), or 1.25 kg/cow of dried distillers grains fed daily. In study 2, 180 cows were stratified by adjusted BW, age, and calving date and assigned to 3 BW blocks with 3 treatments per block for 52 d. Treatments included a liquid protein provided free choice (TNK) or poured into bales at 10% (POR10) or 15% (POR15) of bale weight. Hay DMI, waste, and cow performance (study 2 only) were measured. Daily DMI was not affected by treatment in Studies 1 or 2. In study 1, the POR treatment tended to have less (P = 0.084) hay waste compared with the TNK treatment. In study 2, amount and percentage of hay waste from the POR15 was lower (P < 0.01) compared with the TNK treatment. A treatment by BW block interaction occurred (P < 0.04) and positive differences in BW gain and ADG were observed among treatments (P < 0.01) within BW block. We conclude that treating low- to medium-quality hay with a liquid-protein supplement reduced hay waste but did not increase DMI.