Providing individually housed dairy calves with opportunities for a greater range of natural behaviors, including foraging and grooming, has broad benefits for their behavioral development and performance. We evaluated the effects of providing hay and stationary brushes on performance and time engaged in feeding, grooming, and nonnutritive oral behaviors. Holstein calves were individually housed and assigned at 14 d of age to 1 of 4 treatments providing: a stationary brush (n = 10), chopped coastal bermudagrass hay (n = 9), both a stationary brush and chopped bermudagrass (n = 10), or no brushes nor additional feed (n = 10). Calves had ad libitum access to calf starter and water and were provided 8 L/d pasteurized waste milk fed in 2 meals via a teat bucket. Beginning at 43 d of age, calves were weaned across 10 d. Solid feed intake was measured daily, and growth parameters and cleanliness were measured weekly. Behavioral data were collected on 2 consecutive days at 25 ± 3 d, recorded continuously from video within daylight for 12 h. Provision of hay tended to increase solid feed intake and average daily gain during weaning, and calves provided a brush had improved coat cleanliness during weaning. Calves performed nonnutritive oral behavior, primarily directed toward the pen, with peaks in these abnormal behaviors around milk feeding. The duration of teat-directed nonnutritive sucking was reduced by access to either hay or a brush, compared with neither (3.2 vs. 6.8 min/12 h observation). Provision of a brush reduced pen-directed sucking (38.4 vs. 59.0 min/12 h observation), particularly at milk-feeding time, and also reduced standing time around milk feeding. Self-grooming was not affected by brush or hay access, but provision of the brush increased total time engaged in grooming behaviors (52.9 vs. 40.2 min/12 h observation). These results support benefits of accommodating natural foraging and grooming behaviors, yet reveal a high prevalence of nonnutritive oral behaviors in dairy calves. Overall, these findings underline the importance of environmental complexity in early rearing environments, and compel further consideration of behavioral needs of dairy calves to reduce the development of abnormal behaviors.

为单独饲养的牛犊提供机会进行更广泛的自然行为，包括觅食和修饰，为其行为发展和表现带来广泛的好处。我们评估了提供干草和固定刷对进食，梳理和非营养性口腔行为的性能和时间的影响。荷斯坦犊牛单独饲养，并在14岁时接受4种处理中的1种处理：提供固定刷（n = 10），切碎的沿海百慕大草（n = 9），固定刷和切碎的百慕大草（n = 10） ，或者没有刷子，也没有额外的进纸（n = 10）。犊牛可以随意使用犊牛发酵剂和水，并通过挤奶桶分两次进食8升/天的巴氏消毒废奶。从年龄43 d开始，犊牛断奶10 d。每天测量固体饲料摄入量，每周测量生长参数和清洁度。在25±3 d的连续2天收集行为数据，在日光下连续12 h从视频中连续记录。断奶期间提供干草往往会增加固体饲料的摄入量和平均日增重，而犊牛提供的刷子可使断奶期间的外套清洁度提高。犊牛表现出非营养性的口头行为，主要是针对笔，在喂奶前后这些异常行为达到峰值。通过使用干草或刷子，可以减少奶头定向的非营养性吮吸的持续时间，而两者均没有（3.2 vs. 6.8 min / 12 h观察）。提供刷子减少了笔导向的吮吸（38.4 vs. 59.0 min / 12 h观察），尤其是在喂奶时，并且减少了喂奶时的站立时间。自梳理不受刷或干草进入的影响，但提供刷增加了进行梳理行为的总时间（52.9 vs. 40.2 min / 12 h观察）。这些结果支持了适应自然觅食和修饰行为的好处，但揭示了牛犊中非营养性口腔行为的普遍性。总体而言，这些发现强调了早期饲养环境中环境复杂性的重要性，并迫使人们进一步考虑奶牛的行为需求，以减少异常行为的发展。这些结果支持了适应自然觅食和修饰行为的好处，但揭示了牛犊中非营养性口腔行为的普遍性。总体而言，这些发现强调了早期饲养环境中环境复杂性的重要性，并迫使人们进一步考虑奶牛的行为需求，以减少异常行为的发展。这些结果支持了适应自然觅食和修饰行为的好处，但揭示了牛犊中非营养性口腔行为的普遍性。总体而言，这些发现强调了早期饲养环境中环境复杂性的重要性，并迫使人们进一步考虑奶牛的行为需求，以减少异常行为的发展。