Chang Haomiao, Wang Xinling, Zeng Hanfang, Zhai Yunfei, Huang Ni, Wang Changjian, Han Zhaoyu
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.
Front Vet Sci. 2023 Aug 2;10:1178093. doi: 10.3389/fvets.2023.1178093. eCollection 2023.
Holstein cattle are well known for their high average milk yield but are more susceptible to disease and have lower fecundity than other breeds of cattle. The purpose of this study was to explore the relationship between ruminal metabolites and both milk performance and ruminal microbiota composition as a means of assessing the benefits of crossbreeding Montbéliarde and Holstein cattle. This experiment crossbred Holstein with Montbéliarde cattle, aimed to act as a reference for producing high-quality dairy products and improving the overall efficiency of dairy cattle breeding. Based on similar age, parity and lactation time, 46 cows were selected and divided into two groups (n = 23 per group) for comparison experiment and fed the same formula: Montbéliarde×Holstein (MH, DIM = 33.23 ± 5.61 d), Holstein (H, DIM = 29.27 ± 4.23 d). Dairy herd improvement (DHI) data is an important basis for evaluating the genetic quality of bulls, understanding the quality level of milk, and improving feeding management. We collected the DHI data of these cows in the early lactation, middle lactation and late lactation period of 10 months. The results showed that the average milk production and protein content in Montbéliarde×Holstein were 1.76 kg (34.41 kg to 32.65 kg, > 0.05) and 0.1% (3.54 to 3.44%, < 0.05) higher than in Holstein cattle. Moreover, milk from Montbéliarde×Holstein cattle had lesser somatic cell score (1.66 to 2.02) than Holstein cattle ( < 0.01). A total of 10 experimental cattle in early lactation were randomly selected in the two groups (Lactation time = 92.70 ± 6.81), and ruminal fluid were collected by oral gastric tube. Using 16S rRNA microbial sequencing, we compared the ruminal microbiota composition and found that Montbéliarde×Holstein cattle had a lower abundance of Alphaproteobacteria ( < 0.05) and higher abundance of Selenomonas than Holstein cattle ( < 0.05). These bacteria play roles in protein degradation, nitrogen fixation and lactic acid degradation. The abundance of Succiniclasticum was also greater in Montbéliarde×Holstein cattle ( = 0.053). Through ruminal metabolome analysis, we found that the levels of trans-ferulic acid, pyrrole-2-carboxylic acid, and quinaldic acid were significantly increased in Montbéliarde×Holstein cattle, while that of lathosterol was significantly decreased. The changes in the levels of these metabolites could confer improved antioxidant, anti-inflammatory, and antibacterial activities.
荷斯坦奶牛以其较高的平均产奶量而闻名，但与其他品种的奶牛相比，它们更容易患病且繁殖力较低。本研究的目的是探讨瘤胃代谢物与产奶性能和瘤胃微生物群组成之间的关系，以此作为评估蒙贝利亚牛和荷斯坦奶牛杂交优势的一种手段。本实验将荷斯坦奶牛与蒙贝利亚牛进行杂交，旨在为生产高质量乳制品和提高奶牛养殖的整体效率提供参考。基于相似的年龄、胎次和泌乳时间，选择46头奶牛并分为两组（每组n = 23头）进行对比实验，并投喂相同配方的饲料：蒙贝利亚牛×荷斯坦牛（MH，泌乳天数 = 33.23 ± 5.61天），荷斯坦牛（H，泌乳天数 = 29.27 ± 4.23天）。奶牛群改良（DHI）数据是评估公牛遗传质量、了解牛奶质量水平和改善饲养管理的重要依据。我们收集了这些奶牛在10个月的泌乳早期、中期和晚期的DHI数据。结果表明，蒙贝利亚牛×荷斯坦牛的平均产奶量和蛋白质含量分别比荷斯坦奶牛高1.76千克（从34.41千克降至32.65千克，> 0.05）和0.1%（从3.54%降至3.44%，< 0.05）。此外，蒙贝利亚牛×荷斯坦牛的牛奶体细胞评分（1.66至2.02）低于荷斯坦奶牛（< 0.01）。两组中随机选择10头处于泌乳早期的实验奶牛（泌乳时间 = 92.70 ± 6.81），通过口腔胃管收集瘤胃液。使用16S rRNA微生物测序，我们比较了瘤胃微生物群组成，发现蒙贝利亚牛×荷斯坦牛的α-变形菌门丰度较低（< 0.05），而与荷斯坦奶牛相比，嗜硒菌的丰度较高（< 0.05）。这些细菌在蛋白质降解、固氮和乳酸降解中发挥作用。蒙贝利亚牛×荷斯坦牛中琥珀酸裂解菌的丰度也更高（= 0.053）。通过瘤胃代谢组分析，我们发现蒙贝利亚牛×荷斯坦牛中反式阿魏酸、吡咯-2-羧酸和喹哪啶酸的水平显著升高，而羊毛甾醇的水平则显著降低。这些代谢物水平的变化可能赋予其改善的抗氧化、抗炎和抗菌活性。
