Evaluation of inclusion of hay, dampened hay, and silage in receiving diets of newly weaned beef calves

Objective: The objective of this study was to evaluate the effects of receiving-diet roughage form and source on growth performance of newly received calves. Materials and Methods: An oat crop was harvested as hay or silage and fed as oat hay (OH), dampened oat hay (OHW; 4:1 hay:water), or oat silage (SIL) as the roughage source in soybean hull–based receiving diets to 7-mo-old steer calves across 2 yr (replicates per treatment: yr 1 = 6; yr 2 = 7). Results and Discussion: No differences in cumulative ADG (P = 0.24) or G:F (P = 0.47) were observed, but OH steers consumed less DM (P = 0.02) in yr 1. Cumulatively, no differences in ADG were observed in yr 2 (P = 0.21); however, SIL-fed steers consumed less DM (P < 0.01) than OH or OHW steers, which resulted in greater G:F (P = 0.01). The magnitude of change in proportion of larger particles (i.e., feed particles retained in a 12.7-mm screen) in the bunk from feed delivery to after the meal was almost 4-fold greater for OH than SIL in yr 1 (P = 0.04) and 3.5-fold greater in yr 2 (P = 0.05). As batch fraction (i.e., scale of 0 to 1 representing from which portion of the batch each pen's allotment of feed was derived) progressed, the proportion of larger particles delivered increased (P < 0.01). Implications and Applications: Oat forage in silage form did not adversely affect acceptance of receiving diets for calves, and forage as silage resulted in more uniform feed mixing.