Stress in pre-ruminant calves can impact the functionality of the gastric epithelial lining, thereby impacting calf health during times of stress and potentially later in life. To mitigate this challenge, milk replacers frequently contain antibiotics to reduce the proliferation of harmful bacteria that may result in disease in pre-ruminant, milk supplemented calves. However, there is consumer and regulatory pressure to reduce the reliance on these antimicrobials and evaluate alternatives, such as probiotics, that may shift gut bacterial populations without impacting potential antimicrobial resistance. The objective of this study was to determine if supplementing calves with Lactobacillus and Bacillus species in milk replacer impacts pre-ruminant calf health. The project included 44 calves (50% Angus/50% Holstein) in a randomized complete block design, with calf serving as the experimental unit and age serving as a blocking factor. Calves were fed twice daily one of two treatments: 1) milk replacer with Lactobacillus and two Bacillus species at a total rate of 1.25 x 10^9 cfu/head/day; or 2) non-treated milk replacer. There were 22 replicates per treatment. To determine health status, calves were scored daily based on health indicators for fecal consistency or eye, nose, or ear normality. Health scores were ranked from 0 to 3, with 0 representing normal and 3 signaling severe symptoms, such as bilateral eye or nasal discharge, ear droop, or watery feces. Statistical analysis was performed using the GLIMMIX procedure of SAS. Overall, there was no evidence (P > 0.05) that Lactobacillus and Bacillus inclusion impacted any measured health parameter. Notably, approximately 50% of calves had fecal scores indicating some level of watery stool, but this was not impacted (P > 0.05) by probiotics. In summary, the inclusion of probiotics in calf milk replacer did not appear to impact calf health in the first 30 days.

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PSI-5 代乳品中的芽孢杆菌和乳酸杆菌对犊牛健康的影响

反刍前犊牛的压力会影响胃上皮衬里的功能，从而在压力时期和以后的生活中影响犊牛的健康。为了缓解这一挑战，代乳品经常含有抗生素，以减少有害细菌的增殖，这些细菌可能导致反刍前、补充牛奶的小牛患病。然而，消费者和监管机构面临着减少对这些抗菌剂的依赖并评估替代品（例如益生菌）的压力，这些替代品可能会改变肠道细菌种群而不影响潜在的抗菌素耐药性。本研究的目的是确定在代乳品中补充小牛乳酸杆菌和芽孢杆菌是否会影响反刍前小牛的健康。该项目包括 44 头小牛（50% 安格斯/50% 荷斯坦），采用随机完整区组设计，小牛作为实验单位，年龄作为区组因素。每天给小牛喂食两次，其中一种是两种处理方法之一：1) 乳杆菌和两种芽孢杆菌的代乳品，总速率为 1.25 x 10^9 cfu/头/天；或 2) 未经处理的代乳品。每个处理 22 个重复。为了确定健康状况，每天根据粪便稠度或眼睛、鼻子或耳朵正常性的健康指标对小牛进行评分。健康评分从 0 到 3 进行排序，0 代表正常，3 代表严重症状，例如双侧眼睛或鼻涕、耳朵下垂或水样粪便。使用 SAS 的 GLIMMIX 程序进行统计分析。总体而言，没有证据表明（P > 0。05) 乳酸杆菌和芽孢杆菌含量会影响任何测量的健康参数。值得注意的是，大约 50% 的小牛粪便评分表明存在一定程度的水样粪便，但这并未受到益生菌的影响 (P > 0.05)。总之，在小牛代乳品中添加益生菌似乎不会在前 30 天影响小牛健康。