Abstract The aim of this trial was to investigate the effects of a blend of monoglycerides of short- and medium-chain fatty acids (SMCFA) on health status and growth of preweaned male calves from 16 to 72 days of age. The in vivo study was conducted as a complete randomised block design. Twenty Italian Holstein calves received starter administered ad libitum and 6 L of milk replacer/day (12% powder concentration) and were divided into treated (T) and control (C) groups. A preliminary in vitro antibiotic activity test of SMCFA was performed on several bacterial strains showing a minimum inhibiting concentration ranging from 0.8 to 12.5%. The group T received SMCFA (11 g/day) within the milk replacer while, to obtain isoenergetic liquid diets, the group C received additional 18 g/day of milk replacer powder. Body weight and morphological measurements of the calves were performed weekly. Health scores were checked daily. Faecal and blood samples were collected every two weeks for routine clinical investigations including serum concentration of non-esterified fatty acids and β-Hydroxybutyric acid. At the end of the trial calves were slaughtered and gastrointestinal tract (GIT) organs weighed. The group T reported a better health status and did not require Ab therapy. No differences in biometrical measurements, feed efficiency, blood parameters, and GIT measures were found between the two groups. At 44 days of age, group T showed higher β-Hydroxybutyric acid concentration compared to group C (p < .05). The SMCFA improved the calf health status avoiding the use of antimicrobics. HIGHLIGHTS The monoglycerides of short and medium chain fatty acids improve calf health status. The monoglycerides of short and medium chain fatty acids reduce the need for antibiotic treatment. The monoglycerides of short and medium chain fatty acids reduce the negative impact of enteropathogens.

中文翻译：

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在代乳品中添加含有短链和中链脂肪酸的单酸甘油酯：对断奶前犊牛的健康和生产性能的影响

摘要 本试验的目的是研究短链和中链脂肪酸 (SMCFA) 甘油单酯混合物对 16 至 72 日龄断奶前雄性犊牛健康状况和生长的影响。体内研究是作为一个完整的随机区组设计进行的。20 头意大利荷斯坦小牛接受随意施用的开胃剂和 6 L 代乳品/天（12% 粉末浓度），并分为治疗组 (T) 和对照组 (C)。对几种细菌菌株进行了 SMCFA 的初步体外抗生素活性测试，显示最小抑制浓度范围为 0.8% 至 12.5%。T 组在代乳品中加入 SMCFA（11 克/天），而为了获得等能流质饮食，C 组接受额外的 18 克/天代乳粉。每周对小牛进行体重和形态学测量。每天检查健康评分。每两周收集一次粪便和血液样本用于常规临床研究，包括非酯化脂肪酸和 β-羟基丁酸的血清浓度。在试验结束时屠宰小牛并称重胃肠道 (GIT) 器官。T组报告了更好的健康状况并且不需要Ab治疗。两组之间在生物特征测量、饲料效率、血液参数和胃肠道测量方面没有发现差异。在 44 日龄时，T 组的 β-羟基丁酸浓度高于 C 组（p < .05）。SMCFA 改善了犊牛的健康状况，避免了抗微生物药物的使用。亮点 短链和中链脂肪酸的甘油单酯可改善犊牛的健康状况。短链和中链脂肪酸的甘油单酯减少了对抗生素治疗的需要。短链和中链脂肪酸的甘油单酯减少了肠道病原体的负面影响。