动物营养学报2017,Vol.29Issue(4):1301-1311,11.DOI:10.3969/j.issn.1006-267x.2017.04.027
对禾草源同型发酵和/或异型发酵乳酸菌发酵无芒雀麦青贮有氧稳定性的评价
Evaluation of Aerobic Stability of Bromus inermis Leyss.Silage Fermented by Homofermentative and/or Heterofermentative Lactic Acid Bacteria from Grass
摘要
Abstract
This experiment was conducted to evaluate the action effect of homofermentative and/or heterofer-mentative lactic acid bacteria from grass on aerobic stability of Bromus inermis Leyss. silage. Two homofer-mentative lactic acid bacteria ( LAB) ( a strain of Lactobacillus plantarum and a strain of Enterococcus mundt-ti) and a heterofermentative LAB ( a strain of Lactobacillus buchneri) from grass were selected and were used to prepare fermentation agents. Bromus inermis Leyss. was harvested at the flowering stage, chopped to 2 to 3 cm lengths and treated with fermentation agents. Based on the bacteria type, four treatments were designed:1) control treatment ( con treatment) , which was sprayed with sterile deionized water; 2) heterofermentative treatment ( he treatment) , which was sprayed with Lactobacillus buchneri liquid; 3 ) homofermentative treat-ment ( ho treatment) , which was sprayed with a mixed liquid of Lactobacillus plantarum and Enterococcus mundtti (1:1); 4) heterofermentative+homofermentative treatment (he+ho treatment), which was sprayed with a mixed liquid of Lactobacillus plantarum, Enterococcus mundtti and Lactobacillus buchneri ( 1:1:1 ) . The spraying dose of each treatment was 10 mL/kg fresh forage, and the total bacteria count was about 5 × 105 CFU/g fresh forage. Each treatment had five replicates. After ensiling 60 days under lab condition, the aer-obic stability of Bromus inermis Leyss. silage was evaluated by testing nutrient contents, microbial number and core temperature change. The results showed as follows: at the end of ensiling period ( 60 days) , the pH of four treatments was significantly decreased compared with before silage ( P<0.05) , all treatments silage had a good fermentation quality ( pH≤4.3) and especially ho treatment was the best. When exposed to air, the pH of con and ho treatments increased rapidly, and reached up to 7 on the 8th day of aerobic exposure; the in-creasing extent of pH of he+ho treatment was slightly lower than that of con and ho treatments, and the pH of he+ho treatment reached up to 6.3 on the 8th day of aerobic exposure which was significantly lower than that of con and ho treatments ( P<0.05);the pH of he treatment increased slowly, and only was 4.4 on the 8th day of aerobic exposure which was significantly lower than that of other treatments ( P<0.05) . After 60 days of ensi-ling, the water soluble carbohydrate ( WSC) content of ho treatment was the highest, and significantly higher than that of other treatments ( P<0.05); the WSC content of ho treatment was the lowest, and significantly lower than that of other treatments (P<0.05). When exposed to air, ho treatment silage showed a sharp de-cline in the WSC content while he treatment decreased slowly. On the 8th day of aerobic exposure, the WSC content of he treatment was the highest, he+ho treatment was significantly lower than the former (P<0.05),while con and he treatments was significantly lower than he and he+ho treatments ( P<0.05) . The mold activity was obviously inhibited after silage fermentation, and the inhibitory effect of he and he+ho treatments was bet-ter in which mold was not detected. Moreover, the mold was not detected in the he+ho treatment until the 5th day of aerobic exposure, and it was not detected in the he treatment until the 8th day of aerobic exposure. The yeast quantity of he and he+ho treatments was significantly lower than that of con and he treatments on the 3rd and 5th day of aerobic exposure ( P<0.05) . Lactic and acetic acid concentrations of he and he+ho treatments were significantly higher than those of other 2 treatments on the 8th day of aerobic exposure ( P<0.05) . Aero-bic stability of he, he+ho, con and ho treatments decreased systematically, which showed 194, 126, 62 and 58 h, respectively. Through synthetic analysis, the results indicate that inoculation with Lactobacillus buchneri alone or in combination with homofermentative lactic acid bacteria Lactobacillus plantarum and Enterococcus mundtti can effectively inhibit the aerobic deterioration and ensure the stable quality of Bromus inermis Leyss. silage when exposed to air, even if the former is more effective. The results also confirm that inoculation with homofermentative lactic acid bacteria Lactobacillus plantarum and Enterococcus mundtti cannot play an active role in the improvement of aerobic stability of Bromus inermis Leyss. silage.关键词
无芒雀麦/同型发酵乳酸菌/异型发酵乳酸菌/青贮/有氧稳定性Key words
Bromus inermis Leyss./homofermentative lactic acid bacteria/heterofermentative lactic acid bac-teria/silage/aerobic stability分类
农业科技引用本文复制引用
塔娜,魏日华,德庆哈拉,那日苏,王海..对禾草源同型发酵和/或异型发酵乳酸菌发酵无芒雀麦青贮有氧稳定性的评价[J].动物营养学报,2017,29(4):1301-1311,11.基金项目
中央级公益性科研院所基本科研业务费专项资金(中国农业科学院草原研究所1610332015023) (中国农业科学院草原研究所1610332015023)
"十二五"国家科技支撑计划项目(2012BAD13B07) (2012BAD13B07)