饲粮中添加沙葱粉对安格斯牛营养物质表观消化率及血浆代谢组特征的影响

Effect of Allium mongolicum Regel Powder on Nutrient Apparent Digestibility and Plasma Metabolomics in Angus Calves

【目的】探究饲粮中添加不同水平沙葱粉对安格斯牛营养物质表观消化率及血浆代谢组特征的影响,为将沙葱作为植物添加剂应用于安格斯牛生产提供一定的理论依据。【方法】选取24头安格斯肉牛,随机分为4组,每组6头,其中对照组(CON)肉牛饲喂TMR基础饲粮,各试验组肉牛在基础饲粮基础上分别添加10(LAMR)、15(MAMR)、20(HAMR)g/d沙葱粉。预试期15 d,正试期120 d,其中正试期分2个阶段饲喂,每个阶段各60 d。在正试期第114―120天持续7 d采集饲料样和粪样,用于测定营养物质表观消化率。正试期第113天晨饲前进行血样采集,用于血浆非靶向代谢组学测定。【结果】与对照组相比,LAMR、MAMR组安格斯肉牛粗蛋白质、钙、酸性洗涤纤维及中性洗涤纤维的表观消化率均显著升高(P<0.05),其中LAMR组的效果最佳。血浆代谢组学结果显示,共筛选出62种差异代谢物,其中在正离子模式下11种上调、30种下调;在负离子模式下1种上调、20种下调。这些差异代谢物主要为脂类和类脂类分子、有机酸和衍生物及有机杂环化合物,主要通过上调PC 19∶0_20∶3、PC 18∶0_18∶1、25-羟基胆钙化醇等代谢物调控α-亚麻酸代谢通路,促进安格斯牛对营养物质的利用。【结论】本试验条件下,饲粮中添加10 g/d沙葱粉对安格斯牛的营养物质表观消化率效果最佳,沙葱粉中的活性成分可能通过上调甘油磷脂类化合物(PC 19∶0_20∶3、PC 18∶0_18∶1)、25-羟基胆钙化醇等代谢产物调控α-亚麻酸代谢通路,进而影响肉牛对营养物质的利用。

【Objective】The purpose of this experiment was to explore the effects of different levels of Allium mongolicum Regel powder on nutrient apparent digestibility and the characteristics of plasma metabolomics in Angus calves,in order to provide some theoretical basis for the application of Allium mongolicum Regel as a plant additive in Angus calves production.【Method】Twenty-four Angus calves were randomly divided into 4 groups,with 6 calves in each group.The calves in control group(CON)were fed with TMR basal diet,and the calves in experimental groups were fed with Allium mongolicum Regel powder at the dosage of 10(LAMR),15(MAMR)and 20(HAMR)g/d,respectively.The adaptation period was 15 days and the experimental period lasted for 120 days,the experimental period was divided into 2 parts of 60 days each.Feed and fecal samples were collected for 7 days from 114th-120th days of the experimental period to determine the apparent digestibility of nutrients,and blood samples were collected before the morning feeding on the 113th day of the trial period for the determination of plasma non-targeted metabonomics.【Result】Compared with CON group,the apparent digestibility of crude protein,calcium,acidic detergent fiber and neutral detergent fiber of Angus calves in LAMR and MAMR groups were significantly increased(P<0.05),and the effect of LAMR group was the best.The results of metabonomics showed that 62 differential metabolites were screened out,of which 11 were up-regulated and 30 down-regulated in positive ion mode,and 1 was up-regulated and 20 down-regulated in negative ion mode.These differential metabolites were mainly lipids and lipid-like molecules,organic acids and derivatives and organo-heterocyclic compounds,they mainly regulated the metabolic pathway of alpha-linolenic acid by up-regulating metabolites such as PC 19∶0_20∶3,PC 18∶0_18∶1 and 25-hydroxycholecalciferol,and promoted the utilization of nutrients in Angus calves.【Conclusion】Adding 10 g/d Allium mongolicum Regel powder to the diet had the best effect on the apparent digestibility of nutrients in Angus calves.The active components in Allium mongolicum Regel powder might regulate the pathway of alpha-linolenic acid metabolic by up-regulating the metabolites such as glycerophospholipid compounds(PC 19∶0_20∶3,PC 18∶0_18∶1)and 25-hydroxycholecalciferol,thus affecting the utilization of nutrients in Angus calves.