Abstract
A total of 20 Holstein bulls (422 ± 4.2 kg of BW and 292 ± 0.5 d of age) were allocated in individual pens (2.90 x 1.97 m) and distributed randomly depending on initial BW to 4 treatments that followed a 2 × 2 factorial design (cleaning frequency: once a wk vs once every 2 wks; and straw bedding length: long vs chopped). Concentrate and straw were recorded daily, BW biweekly for 56 days. Weekly before 7 kg of straw bedding were added or pen was cleaned animal behavior, animal and pen cleanliness scoring were recorded. Data were analyzed with an analysis of variance or a Chi-Square.Concentrate (8.9 ± 0.37 kg/d) and straw intake (0.9 ± 0.13 kg/d) did not differ among treatments, however ADG and efficiency were lesser (interaction P ˂ 0.05) when bulls were bedded with long straw and cleaned every 2 wks (1.38 ± 0.095 kg/d and 0.14 ± 0.007 kg/kg, respectively) compared with the other treatments (1.66 ± 0.095 kg/d and 0.17 ± 0.007 kg/kg, respectively). When bulls were cleaned biweekkly compared with once a wk, ruminating decreased (P < 0.01, 2.53 vs 2.10 ± 0.067 times every 15 min), selfgrooming increased (P < 0.01, 0.84 vs 1.59 ± 0.067 times every 15 min), and stereotypies tended to increase (P = 0.06, 0.09 vs 0.23 ± 0.020 times every 15 min).Animals bedded in long straw and cleaned every 2 wks were dirtier, followed by the animals bedded with chopped straw and cleaned every 2 wks, bedded in long straw cleaned once a wk, and the cleanest pens and bulls were the once that were bedded in chopped straw and cleaned once a week.Bedding the animals in long straw and cleaning biweekly impairs performance, animal welfare (rumination, stereotypies) and cleanliness of the animal and the pen.