吉林省花生秧与花生壳的体外发酵特性

In vitro fermentation characteristics of peanut vines and peanut shells in Jilin Province

为利用体外产气法评定吉林省花生(Arachis hypogaea)两种副产物(花生秧、花生壳)的营养价值,本研究以3头装有永久性瘤胃瘘管的草原红牛为试验动物,测定花生秧、花生壳、羊草(Leymus chinensis)不同时间点(2、4、6、8、12、24 h)累计产气量、产气动力学参数及体外发酵24 h挥发性脂肪酸(volatile fatty acid,VFA)含量、pH、氨态氮浓度和微生物蛋白(microbial crude protein,MCP)含量。结果表明:1)花生秧不同时间点累计产气量、理论最大产气量和达到最大产气量1/2时的产气速率显著高于花生壳和羊草(P<0.05);羊草的产气速率和产气延滞时间显著高于花生秧和花生壳(P<0.05)。2)羊草的pH显著高于花生秧和花生壳(P<0.05);花生秧的总挥发性脂肪酸(total volatile fatty acid,TVFA)含量和丙酸比例显著高于花生壳和羊草(P<0.05);羊草的丁酸比例和乙酸/丙酸值显著高于花生秧和花生壳(P<0.05);乙酸比例三者之间差异不显著(P>0.05)。3)花生秧的微生物蛋白含量显著高于花生壳和羊草(P<0.05);羊草的氨态氮浓度显著高于花生秧和花生壳(P<0.05)。综上所述,花生秧的体外发酵效果最优,营养价值高;花生壳的利用率低,日粮添加比例不宜过大。

To evaluate the nutritional value of two kinds of peanut(Arachis hyprogaea)by-products(peanut vines and peanut shells)in the Jilin Province using the in vitro gas production technique,three steppe red cattle with permanent rumen fistulas were used as experimental animals.The cumulative gas production at different time points(2,4,6,8,12,24 h)and volatile fatty acid yield content,pH,ammonia nitrogen concentration,and microbial protein content after 24 h of in vitro fermentation of peanut vines,peanut shells,and Chinese leymus(Leymus chinensis)were determined.The results showed as follows:1)the cumulative gas production,theoretical maximum gas production,and gas production rate when gas production was 1/2 of the maximum for peanut vines were significantly higher than those for peanut shells and Chinese leymus(P<0.05).The gas production rate and lag time of gas production of Chinese leymus were significantly higher than those of peanut vines and shells(P<0.05);2)the pH of Chinese leymus was significantly higher than that of peanut vines and shells(P<0.05),the total volatile fatty acid yield and propionic acid ratio of the peanut vines were significantly higher than those of peanut shells and Chinese leymus(P<0.05),and the butyric acid ratio and acetic acid/propionic acid value of Chinese leymus were significantly higher than those of peanut vines and shells(P<0.05).There was no significant difference in the acetic acid ratio among three groups(P>0.05);and 3)the microbial protein content of peanut vines was significantly higher than that of peanut shells and Chinese leymus(P<0.05)and the ammonia nitrogen concentration of Chinese leymus was significantly higher than that of peanut vines and shells(P<0.05).In conclusion,in vitro fermentation of peanut vines exhibited the best effects and high nutritional value.The utilization rate of peanut shells was low and their proportion in dietary supplementation should not be large.