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PSXI-14 Effects of pen cleaning on feedlot performance and carcass characteristics of beef steers fed during the winter in the northern Great Plains


 The objective of this study was to evaluate the impacts of winter pen cleaning on livestock performance of beef cattle fed to finish in the Northern Great Plains. One hundred fifty-six mixed-breed beef steers (284 ± 14 kg) were assigned to one of 12 pens. Treatments were assigned randomly to pen and consisted of: 1) Control - no cleaning, 2) Apron - bunk aprons (approximately 3 m behind the bunk) cleaned twice throughout the study, and 3) Full - entirety of the pen cleaned twice throughout the study. Full pens or bunk aprons were cleaned on two occasions at 56-day intervals. Pens were stocked at a similar density, approximately 26.9 m2 of pen space per steer. Steers were adapted to and finished a common finishing diet. Cattle were provided fresh bedding weekly, with an estimated 2.5 kg cereal straw·steer−1·d−1 used as bedding during the study. Pen cleaning did not influence (P ≥ 0.48) final body weight (628 ± 12 kg), or average daily gain (1.8 ± 0.03 kg/d). Dry matter intake (10.6 ± 0.24 kg) and feed efficiency (0.167 kg gain:kg dry matter intake) were similar (P ≥ 0.55) across treatment. Hot carcass weight, ribeye area, back fat and yield grade of carcasses were not affected (P ≥ 0.44) by pen cleaning treatment. Increasing extent of pen cleaning increased marbling score (P = 0.03; 444, 463, and 484 ± 11.1 for control, apron, and full, respectively). Quality grade was greater (P < 0.05) in carcasses resulting from steers managed with either pen cleaning strategy compared to control. Further, increasing extent of pen cleaning increased (P = 0.03) quality grade of carcasses. Pen cleaning did not improve animal performance in this study, which was unexpected. Further research on the accumulation of marbling over time with different pen cleaning systems is warranted.