Swath-grazing oat or grazing stockpiled perennial grass compared with a traditional winter feeding method for beef cows in central Alberta

摘要

Swath-grazed oat (Avena sativa L.) and stockpiled meadow bromegrass (Bromus riparius Rhem) were compared with (Control) a pen-fed straw-based total mixed ration (TMR) for dry, pregnant beef cows (670 +/- 88 kg BW) using carrying capacity, nutritive value, cow performance, daily feeding, yardage, and total daily costs. Carrying capacity ranked (P < 0.05): oat (637 cow-d ha(-1)) > Control (454 cow-d ha(-1)) > stockpiled grass (189 cow-d ha(-1)). In vitro true digestibility (IVTD) ranked (P < 0.05): stockpiled forage (681 g kg(-1))> oat (588 g kg(-1)) > Control (530 g kg(-1)). Average cow body condition score (BCS) off pasture was (P < 0.05): stockpiled grass (3.4) > oat (3.0), while the control was intermediate (3.3). The daily feed cost ranked: stockpiled grass ($0.38 cow-d(-1)) < swathed oat ($0.48 cow-d(-1)) < Control ($1.05 cow-d(-1)). Yardage (non-feed costs) ranked: oat ($0.41 cow-d(-1)) < stockpiled ($0.50 cow-d(-1)) < Control ($0.91 cow-d(-1)). Total daily cost was similar for oat ($1.07 cow-d(-1)) and stockpiled grass ($1.04 cow-d(-1)), both less (P < 0.05) than the control ($2.25 cow-d(-1)). The cost of both grazing treatments was comparable to other research, but the stockpiled treatment cost was limited by the low yield of forage regrowth.