文献类型： 外文期刊

作者： Liu, Zixin ¹ ; Yan, Fuyong ³ ; Mi, Hui ¹ ; Lv, Xiaokang ¹ ; Wang, Kaijun ⁴ ; Li, Bin ⁵ ; Jin, Tao ⁵ ; Chen, Liang ¹ ; Zhang, Guijie ⁶ ; Huang, Ximei ⁷ ; Zhou, Chuanshe ¹ ; Tan, Zhiliang ¹ ;

作者机构： 1.Inst Subtrop Agr, Inst Subtrop Agr, CAS Key Lab Agriecol Proc Subtrop Reg, Natl Engn Lab Pollut CON & Waste Utilizat Livestoc, Changsha, Peoples R China

2.Univ Chinese Acad Sci, Beijing, Peoples R China

3.Hunan Jiuding Technol Grp Co Ltd, Changsha, Peoples R China

4.Guangxi Univ, Coll Anim Sci & Technol, Nanning, Peoples R China

5.Tibet Acad Agr & Anim Husb Sci, Inst Anim Sci, Lhasa, Peoples R China

6.Ningxia Univ, Sch Agr, Yinchuan, Peoples R China

7.Changsha Green Top Biotech Co Ltd, Changsha, Peoples R China

关键词： Jersey dairy cows; NCG supplements; metabolism; high altitude; milk quality; feed additives; digestibility; rumen fermentation

期刊名称：FRONTIERS IN VETERINARY SCIENCE （ 影响因子：3.471； 五年影响因子：3.821 ）

ISSN：

年卷期： 2022 年 9 卷

页码：

收录情况： SCI

摘要： This study aimed to assess the impact of the dietary supplementation of N-carbamoylglutamate (NCG) on nutrient digestibility, rumen fermentation, milk quality, oxidative stress, and metabolites in the plasma and feces of Jersey cattle under high altitude with the hypoxic condition. A total of 14 healthy lactating Jersey dairy cows with similar body conditions were selected and randomly divided into 2 groups. The control group (CON group, N = 6 replicates) was fed with a conventional complete diet, whereas the experimental group (NCG group, N = 8 replicates) received 20 g/d per head NCG supplementation. The experiment lasted for 60 days, the adaptation period was 12 days, and the formal experiment period was 48 days. Except that the NCG group showed an upward trend in dry matter intake (DMI) (p = 0.09) and the fermentation parameters, the molar proportion of butyric acid tended to decrease (p = 0.08); the two groups had no significant differences (p > 0.05) in nutrients digestibility, plasma immunity, and antioxidant ability. However, compared with the CON group, the milk fat rate and blood oxygen saturation of the NCG group showed an upward trend (p = 0.09). For indexes associated with altitude stress, the contents of thyroxine, transferrin, and endothelin both decreased significantly (p < 0.05) in the NCG group. Meanwhile, heat shock protein (p = 0.07) and aldosterone (p = 0.06) also showed a downward trend. A total of 114 different metabolites were identified from feces and plasma, 42 metabolites were derived from plasma that mainly included 5 kinds of Super Class, and 72 metabolites were derived from feces that mainly included 9 kinds of Super Class. The significantly increased plasma differential metabolites were 2,5-dihydroxybenzoate and salicyluric acid, and the significantly increased fecal differential metabolites were Butenafine (fold change > 2). Pathway analysis showed that after applying NCG as a feed additive, the changes of the Jersey dairy cows mainly focused on amino acid metabolism and lipid metabolism. These results indicated that adding NCG to the diet can prevent the hypoxic stress state of lactating Jersey cows in high-altitude areas and has a tendency to improve milk quality.