发酵苹果渣全混合日粮对肉牛育肥性能和胃肠道细菌组成的影响

Effects of fermented apple pomace based TMR on the performance and gastrointestinal bacteria community of beef cattle

苹果(Malus pumila)渣是一种富含多糖和维生素等多种营养物质的天然饲料,但含水量高不易保存,严重限制其应用于反刍动物养殖。本试验把苹果渣混在日粮中制备成发酵型全混合日粮,利用产阿魏酸酯酶的植物乳杆菌A1促进发酵,研究发酵型全混合日粮对肉牛生长性能、血常规和胃肠道微生物的影响。试验采用单因素完全随机试验设计,选取50头健康、体重相近[(630.0±5.5)kg]的西门塔尔肉牛,随机均分为两个处理组。其中,对照组(CON)饲喂典型育肥肉牛普通全混合肉牛饲料,试验组(FTMR)饲喂发酵型全混合日粮。整个试验周期60 d,其中包括15 d预饲期。结果表明,与对照组相比,饲喂发酵全混合日粮显著提高肉牛平均日增重(P<0.01)、粗蛋白质表观消化率(P<0.01),降低了肉牛白细胞总数(P=0.039)、血红蛋白含量(P<0.01)和血小板分布宽度(P=0.039),提高了肉牛瘤胃中总挥发性脂肪酸(P=0.026)、乙酸(P=0.023)和丙酸(P=0.039)的浓度。发酵全混合日粮对肉牛胃肠道细菌多样性没有显著影响(P>0.05),但提高了肉牛瘤胃纤维杆菌门(Fibrobacterota)、纤维杆菌属(Fibrobacter)、普雷沃氏菌属(Prevotella)和毛螺菌属(Lachnospira)的相对丰度显著(P<0.05)。在属水平上,发酵全混合日粮组盲肠细菌中梭状芽孢杆菌(Clostridium_sensu_stricto_1)和狄氏副拟杆菌(Parabacteroides)的细菌丰度均显著高于对照组(P<0.05)。综上所述,饲喂添加苹果渣发酵型全混合日粮可以提高肉牛生产性能、改善瘤胃发酵参数,增加胃肠道有益菌属。因此,发酵饲料技术可以高效利用难保存的饲料原料,对挖掘非常规饲料资源有重要意义。

Apple pomace is a by-product of juice industry which rich in polysaccharides and vitamins.But it is also characterized with high-water content that is hard to preserve,which severely restricts its application in ruminant husbandry.In this experiment,apple pomace was mixed into the diet to prepare a fermented total mixed diet(FTMR)utilizing ferulic esterase-producing Lactobacillus plantarum A1 to promote fermentation,and to study the effects of FRMR on growth performance,blood parameters and gastrointestinal microorganisms of beef cattle.The experiment was designed as a oneway completely randomized trial.A total of 50 Simmental steers with similar body weight[(630.0±5.5)kg]were randomly assigned to the regular TMR dietary treatment(CON)or FTMR treatment.The total period of the whole experiment was 60 d,including a pre-feeding period of 15 d.The results showed that FTMR treatment significantly increased average daily gain(P<0.01),apparent digestibility of crude protein(P<0.01),but decreased count of white blood cells(P=0.039),hemoglobin content(P<0.01)and platelet distribution width(P=0.039).The concentrations of total volatile fatty acids(P=0.026),acetate(P=0.023)and propionate(P=0.039)in rumen were increased.The FTMR treatment significantly increased the relative abundance of Fibrobacterota,Fibrobacter,Prevotella and Lachnospira in rumen(P<0.05)compared to the CON treatment.At the genus level,the abundances of Clostridium_sensu_stricto_1 and Parabacteroides in cecum was significantly higher in the FTMR treatment than those in the CON treatment(P<0.05).In conclusion,the fermented total mixed diet supplemented with apple residue could improve the performance and rumen fermentation parameters,as well as increase beneficial bacteria in gastrointestinal tract of steers.Therefore,fermented TMR technology can efficiently utilize the feedstuffs that were difficult to preserve,and it is important for the development of unconventional feed resources.