Key Laboratory of Superior Forage Germplasm in the Qinghai-Tibetan Plateau, Grassland Institute, Qinghai Academy of Animal Science and Veterinary Medicine, Qinghai University, Xining 810016, China.
School of Mathematics and Statistics, Qinghai Normal University, Xining 810016, China.
Lett Appl Microbiol. 2023 Feb 16;76(2). doi: 10.1093/lambio/ovad018.
To investigate the characteristics of different LAB strains isolated from subtropics and their effects on Napier grass (Pennisetum purpureum Schum.) silage with two dry matter (DM) levels, sugar fermentation pattern, and growth profiles of three screened lactic acid bacteria (LAB) strains [Pediococcus pentosaceus (PP04), Weissella cibaria (WC10), and Lactobacillus plantarum (LP694)] were characterized, and then used either individually or in combination at 1.0 × 106 cfu g-1 fresh weight to inoculate grass having 15% or 25% DM. Treatments were applied: (1) no inoculant (control); (2) PP04; (3) WC10; (4) LP694; (5) M-1 (PP04: WC10 = 2:1); (6) M-2 (PP04: LP694 = 1:2); (7) M-3 (WC10: LP694 = 2:1); (8) M-4 (PP04: WC10: LP694 = 2:1:1). The results showed that all inoculations increased LAB, DM recovery, and lactic acid (LA) concentration, while decreasing pH, the ammonia nitrogen/total nitrogen (NH3-N/TN), and butyric acid (BA) concentration compared to control group in both DM. However, the effect of inoculations was very limited at 15% DM. Silages with inoculants achieved higher silage quality at 25% DM than 15% DM. The different LAB inoculants result in significant differences in silage quality, while W. cibaria decreased the pH and inhibited the growth of undesirable bacteria and those characteristics were not affected by the DM content.
为了研究亚热带地区不同 LAB 菌株的特性及其对两种干物质（DM）水平下的象草（Pennisetum purpureum Schum.）青贮的影响，对三种筛选出的乳酸菌（LAB）菌株[戊糖片球菌（PP04）、魏斯氏菌（WC10）和植物乳杆菌（LP694）]的糖发酵模式和生长特性进行了研究，然后分别或组合使用 1.0×106cfu/g 新鲜重的这些 LAB 菌株接种 DM 含量为 15%或 25%的象草。处理方法如下：（1）不接种（对照）；（2）PP04；（3）WC10；（4）LP694；（5）M-1（PP04：WC10=2:1）；（6）M-2（PP04：LP694=1:2）；（7）M-3（WC10：LP694=2:1）；（8）M-4（PP04：WC10：LP694=2:1:1）。结果表明，与对照组相比，所有接种均能增加 LAB、DM 回收率和乳酸（LA）浓度，降低 pH 值、氨氮/总氮（NH3-N/TN）和丁酸（BA）浓度，无论 DM 水平如何。然而，接种的效果在 DM 为 15%时非常有限。在 DM 为 25%时，添加发酵剂的青贮饲料比 DM 为 15%时具有更高的青贮质量。不同的 LAB 接种剂对青贮饲料的质量有显著影响，而魏斯氏菌降低了 pH 值，抑制了不良细菌的生长，这些特性不受 DM 含量的影响。
