Zhao Chenxu, Shen Bingyu, Huang Yan, Kong Yezi, Tan Panpan, Zhou Yi, Yang Jiaqi, Xu Chuang, Wang Jianguo
College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China.
College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163000, China.
Microorganisms. 2023 Jun 21;11(7):1625. doi: 10.3390/microorganisms11071625.
Chromium propionate (Cr-Pro) and calcium propionate (Ca-Pro) are widely applied in dairy production, especially in the alleviation of heat stress (HS). HS can reduce the abundance of rumen microbiota and the lactation performance of dairy cows. The present work mainly focused on evaluating the effects of Cr-Pro and Ca-Pro on the performance, ruminal bacterial community, and stress of postpartum HS dairy cows as well as identifying the differences in their mechanisms. Fifteen multiparous postpartum Holstein cows with equivalent weights (694 ± 28 kg) and milk yields (41.2 ± 1.21 kg/day) were randomly divided into three groups: control (CON), Cr-Pro (CRPR), and Ca-Pro (CAPR). The control cows received the basal total mixed ration (TMR) diet, while the CRPR group received TMR with 3.13 g/day of Cr-Pro, and the CAPR group received TMR with 200 g/day of Ca-Pro. The rumen microbial 16S rRNA was sequenced using the Illumina NovaSeq platform along with the measurement of ruminal volatile fatty acids (VFAs) and milking performance. Cr-Pro and Ca-Pro improved lactation performance, increased the rumen VFA concentration, and altered the rumen microbiota of the HS dairy cows. Cr-Pro significantly improved the milk yield ( < 0.01). The richness and diversity of the microbial species significantly increased after feeding on Ca-Pro ( < 0.05). Gene function prediction revealed increased metabolic pathways and biological-synthesis-related function in the groups supplemented with Cr-Pro and Ca-Pro. Our results indicate that the application of Cr-Pro or Ca-Pro can provide relief for heat stress in dairy cows through different mechanisms, and a combination of both is recommended for optimal results in production.
丙酸铬（Cr-Pro）和丙酸钙（Ca-Pro）在奶牛生产中广泛应用，尤其在缓解热应激（HS）方面。热应激会减少瘤胃微生物群数量并降低奶牛的泌乳性能。本研究主要聚焦于评估丙酸铬和丙酸钙对产后热应激奶牛的生产性能、瘤胃细菌群落及应激的影响，并确定它们作用机制的差异。15头体重相当（694±28千克）且产奶量相当（41.2±1.21千克/天）的经产产后荷斯坦奶牛被随机分为三组：对照组（CON）、丙酸铬组（CRPR）和丙酸钙组（CAPR）。对照组奶牛饲喂基础全混合日粮（TMR），而CRPR组奶牛饲喂添加了每天3.13克丙酸铬的TMR，CAPR组奶牛饲喂添加了每天200克丙酸钙的TMR。使用Illumina NovaSeq平台对瘤胃微生物16S rRNA进行测序，并测定瘤胃挥发性脂肪酸（VFA）和挤奶性能。丙酸铬和丙酸钙改善了泌乳性能，提高了瘤胃VFA浓度，并改变了热应激奶牛的瘤胃微生物群。丙酸铬显著提高了产奶量（<0.01）。饲喂丙酸钙后，微生物物种的丰富度和多样性显著增加（<0.05）。基因功能预测显示，在添加丙酸铬和丙酸钙的组中，代谢途径和生物合成相关功能有所增加。我们的结果表明，应用丙酸铬或丙酸钙可通过不同机制缓解奶牛的热应激，建议两者联合使用以在生产中获得最佳效果。
