The effects of replacement of whole‐plant corn with oat and common vetch on the fermentation quality,chemical composition and aerobic stability of total mixed ration silage in Tibet

The objective of this experiment was to evaluate the effects of replacement of whole‐plant corn with oat and common vetch on the fermentation quality, chemical composition and aerobic stability of total mixed ration (TMR) silage in Tibet. Four TMR that varied in the forage sources on dry matter basis were used: (i) 52% whole‐plant corn (Control); (ii) 43% oat + 12% common vetch (OC3.6); (iii) 38% oat + 18% common vetch (OC2.2); and (iv) 33% oat + 23% common vetch (OC1.5). Silos were opened on day 45 and then subjected to an aerobic stability test for 12 days. The results showed that all silages were well preserved with low pH and NH₃‐N, and high lactic acid and V‐scores. With the increasing proportion of common vetch, crude protein, ether extract increased (P < 0.05), and neutral detergent fiber and acid detergent fiber decreased (P < 0.05). Under aerobic conditions, treated silages were more stable than the control silage as indicated by lower (P < 0.05) pH and yeast population. It was concluded that replacement of whole‐plant corn with oat and common vetch had no unfavorable effects on the fermentation quality and improved crude protein content and aerobic stability of TMR silage. OC2.2 silage was the best among three treated TMR silages.     

Fermentation quality and aerobic stability of mulberry silage prepared with lactic acid bacteria and propionic acid

The objective of this study was to examine the fermentation quality and aerobic stability of mulberry (Morus alba L.) silage prepared with lactic acid bacteria (LAB) and propionic acid (PA). The selected LAB strains Lactobacillus (L.) plantarum LC365281 (L1) and L. brevis LC365282 (L2), and commercial inoculant strains L. plantarum Gaofuji (GF) and L. buchneri Fresh (FR), and PA were used as additives for silage preparation. Silage treatments were designed as control, L1, L2, GF, FR, PA, PA + L1, PA + L2, PA + GF, or PA + FR. After 30 days of ensiling, the fermentation quality of silages treated with PA + L1 was improved, with a lower (p < 0.05) pH and NH₃‐N content than those of other treatments. During the aerobic exposure, the PA + LAB‐treated silages displayed an aerobic stability with stable pH value and lactic acid content. The results confirm that L. plantarum L1 and PA were the best additive combination for ensiling mulberry.     

Effect of ensiling whole crop oat with lucerne in different ratios on fermentation quality,aerobic stability and in vitro digestibility on the Tibetan plateau

The objective of this study was to determine the effect of ensiling different ratios of whole crop oat to lucerne on fermentation quality, aerobic stability and in vitro digestibility of silage on the Tibetan plateau. Four experimental treatments were produced varying in the ratio of forages on a fresh matter (FM) basis: 1) 100% oat (control, dry matter (DM) content: 317 g/kg), 2) 90% oat + 10% lucerne (OL10, DM content: 316 g/kg), 3) 80% oat+ 20% lucerne (OL20, DM content: 317 g/kg) and 4) 70% oat+ 30% lucerne (OL30, DM content: 318 g/kg). All treatments were packed into laboratory‐scale silos and ensiled for 60 days and then subjected to an aerobic stability test for 15 days. Further, the four experimental treatments were incubated in vitro with buffered rumen fluid to study the nutrient digestibility. All silages were well preserved with low pH and NH₃‐N contents, and high lactic acid contents and V‐scores (evaluation of silage quality). Increasing the lucerne proportion increased (p < 0.05) crude protein (CP) content of silage, whereas neutral (NDF) and acid (ADF) detergent fibre contents were not affected. Under aerobic conditions, the control silage showed higher (p < 0.05) yeast counts (>10⁵ cfu/g FM) followed by OL10 silage, and OL10 silage improved aerobic stability for 74 h. OL20 and OL30 silages showed fewer (p < 0.05) yeasts (<10⁵ cfu/g FM) and markedly (p < 0.05) improved the aerobic stability (>360 h). After 48‐h incubation, OL30 silage increased (p < 0.05) in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) compared with the control silage. These results suggest that replacing oat with lucerne had no unfavourable effects on fermentation quality of silage, but improved CP content, aerobic stability IVDMD and IVNDFD. OL30 silage was the best among the three mixed silages.     

Effect of grape pomace on fermentation quality and aerobic stability of sweet sorghum silage

The objective of this study was to evaluate the effect of grape pomace (GP) with different adding levels (0%, 5%, 10% and 15%, fresh matter basis), alone (GP‐LAB) or in combine with an inoculant LAB (GP+LAB), on the fermentation quality and aerobic stability of sweet sorghum silage. After 90 days of ensiling in vacuumized mini‐silos, silages were subject to a 7‐day aerobic stability test, in which chemical, microbial and polyphenol composition were measured. In the GP‐LAB group, adding GP decreased (P < 0.05) concentrations of water‐soluble carbohydrate (WSC) and butyric acid in silage. In the GP+LAB group, adding GP increased (P < 0.05) concentrations of lactic acid, WSC and crude protein, decreased (P < 0.05) final pH value, NH₃‐N ratio and butyric acid concentration in silage. Polyphenol level was reduced (P < 0.05) after silage fermentation. During aerobic exposure, the fungi count, pH value and silage temperature increased (P < 0.05), the levels of lactic acid, acetic acid and polyphenols (quercetin 3‐O‐glucoside and quercetin 3‐O‐glucuronid) decreased (P < 0.05) in silage. GP+LAB treated silage had a lag phase for aerobic spoilage. When the fermentation products, microbial counts, chemical and polyphenol composition were considered, the use of 10% GP+LAB at ensiling could provide a valuable source for improved fermentation quality and aerobic stability of sweet sorghum silage.     

Microbial population,chemical composition and silage fermentation of cassava residues

In order to effectively use the cassava (Manihot esculenta Crantz) residues, including cassava leaves, peel and pulp for livestock diets, the chemical and microbiological composition, silage preparation and the effects of lactic acid bacteria (LAB) inoculants on silage fermentation of cassava residues were studied. These residues contained 10⁴ to 10⁵ LAB and yeasts, 10³ to 10⁴ coliform bacteria and 10⁴ aerobic bacteria in colony forming units (cfu) on a fresh matter (FM) basis. The molds were consistently at or below the detectable level (10² cfu of FM) in three kinds of cassava residues. Dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) content of cassava residues were 17.50‐30.95%, 1.30‐16.41% and 25.40–52.90% on a DM basis, respectively. The silage treatments were designed as control silage without additive (CO) or with LAB inoculants Chikuso‐1 (CH, Lactobacillus plantarum) and Snow Lacto (SN, Lactobacillus rhamnosus) at a rate of 5 mg/kg of FM basis. All silages were well preserved with a low pH (below 4.0) value and when cassava residues silage treated with inoculants CH and SN improved fermentation quality with a lower pH, butyric acid and higher lactic acid than control silage.     

Silage preparation and fermentation quality of kudzu,sugarcane top and their mixture treated with lactic acid bacteria,molasses and cellulase

We studied silage fermentation of kudzu (KZ), sugarcane top (ST) and their mixtures treated with additives to be able to effectively use available local feed resources. The silages were prepared using KZ, ST, KZ 90% + ST 10%, KZ 80% + ST 20%, KZ 70% + ST 30% and KZ 60% + ST 40%, based on fresh matter (FM). These silages were treated with 10⁸ colony‐forming units/g epiphytic lactic acid bacteria (LAB), 5% molasses and 0.02% cellulase of FM. The KZ contained higher crude protein (CP; 14.52%) content and lower levels of neutral detergent fiber (NDF; 62.15%) than those of ST (6.84% CP and 64.93% NDF) based on dry matter (DM). The KZ 60% + ST 40% silage fermented well with a higher (P < 0.05) lactic acid content and lower (P < 0.05) pH than those of the other mixed silages. Silages treated with molasses had lower (P < 0.05) ammonia‐N, NDF, acid detergent fiber, and hemi‐cellulose contents as well as pH, but higher (P < 0.05) DM, water‐soluble carbohydrate, and lactic acid contents, than those of the control, LAB and cellulase treatments. The results confirmed that KZ 60% + ST 40% was the best mixing ratio to prepare silage, and molasses improved silage fermentation and fiber degradation.     

添加丙酸对青稞秸秆和多年生黑麦草混合青贮发酵品质及有氧稳定性的影响

为探讨不同水平丙酸对青稞(Hordeum vulgare)秸秆和多年生黑麦草(Lolium perenne)混合青贮发酵品质及有氧稳定性的影响,试验设0(CK), 0.3%(PA3), 0.4%(PA4)和0.5%丙酸(PA5)4个处理组。青贮后第30 d开窖取样测定发酵品质,并有氧暴露12 d分析有氧稳定性。结果表明:各组pH值、乳酸和干物质含量差异不显著,但丙酸添加组乳酸/乙酸(除PA3组)和水溶性碳水化合物含量显著高于对照组(P<0.05),氨态氮/总氮和丁酸含量显著低于对照组(P<0.05)。有氧暴露阶段,PA4和PA5组pH值与对照组和PA3组相比上升幅度较小,乳酸、干物质含量损失较少,且水溶性碳水化合物含量随着丙酸添加量的增大而升高。随着暴露时间延长,各组氨态氮/总氮值和丁酸含量逐渐升高,且PA4和PA5组显著低于对照组和PA3组(P<0.05)。表明添加0.4%以上的丙酸能够改善混合青贮饲料的发酵品质和有氧稳定性。     

Fermentation quality and chemical composition of shrub silage treated with lactic acid bacteria inoculants and cellulase additives

Effects of lactic acid bacteria (LAB) inoculants and cellulase additives on fermentation quality and chemical compositions of shrub silages were studied by using a small‐scale fermentation system. Two LAB inoculants of Qingbao (Lactobacillus plantarum, Pediococcus acidilacticii, Lactobacillus casei and Clostridium phage) and Caihe (Lactobacillus plantarum, Lactobacillus brevis and Pediococcus acidilactici) and a commercial cellulase made from Trichoderma reesei were used as additives for intermediate pea‐shrub, rush bushclover, arborescent ceratoides and shrubby silage preparation. The crude protein, neutral detergent fiber and water‐soluble carbohydrate contents of the four shrub materials were 10.1–14.2, 62.6–67.2 and 1.9–3.5% on a dry matter basis, respectively. All shrub silages had pH 3.40–4.43, ammonia‐N 0.1–0.2% g/kg and lactic acid 1.3–2.9% on a fresh matter basis. The silage quality of LAB‐inoculated silages did not have a greater effect than control silages, except shrubby silage preparation. Silages treated with the cellulase, the pH of rush bushclover and shrubby sweetvetch silage were significantly (P < 0.05) lower and the lactic acid content were significantly (P < 0.05) higher than the control silages. The results confirmed that shrub contained a relatively high content of crude protein; its silages can be preserved in good quality, and they are new potential resources for livestock feed.     

乳酸菌及丙酸钙对全株玉米和燕麦青贮饲料发酵品质和霉菌毒素含量的影响

为研究乳酸菌及丙酸钙对全株玉米和燕麦青贮饲料发酵品质、营养品质、微生物数量、霉菌毒素含量及有氧稳定性的影响,利用蒸馏水（CK组）、复合乳酸菌（LAB组,添加量为5×10⁵ CFU·g^-1鲜样）、丙酸钙（PACA组,添加量为鲜草重的0.4%）以及乳酸菌和丙酸钙复合（LAB+PACA）分别添加进全株玉米和燕麦原料中青贮120 d。结果表明：全株玉米青贮饲料发酵品质优良而萎蔫后的燕麦青贮丁酸和氨态氮含量较高。添加剂在不同青贮饲料中表现不同。所有添加剂均显著提高了燕麦青贮饲料的乳酸和乙酸含量,降低了pH值、氨态氮、丁酸含量和酵母菌数量（P<0.05）。而PACA和LAB+PACA组则显著提高了玉米青贮饲料中的淀粉和可溶性碳水化合物含量和有氧稳定性并且降低了霉菌和酵母菌数量（P<0.05）。LAB和LAB+PACA的使用有效降低了玉米青贮饲料中的黄曲霉毒素B1含量（P<0.05）。在两种青贮饲料中丙酸含量只有PACA和LAB+PACA组能够显著增加。因此,添加剂尤其是LAB+PACA的复合添加对于提高玉米和燕麦青贮饲料的青贮品质和安全性具有重要作用。     

A third-generation esterase inoculant alters fermentation pattern and improves aerobic stability of barley silage and the efficiency of body weight gain of growing feedlot cattle

This study investigated the effects of a mixed bacterial inoculant possessing ferulic acid esterase (FAE) activity on silage fermentation characteristics, aerobic stability, and growth performance of growing feedlot steers. Whole-crop barley (Hordeum vulgare L.) forage (35% DM) was chopped and ensiled without a silage inoculant (UN) or with a mixed bacterial culture containing 1.0 × 10(11) cfu/g of Lactobacillus buchneri LN4017 that produces FAE, 2.0 × 10(10) cfu/g of Lactobacillus plantarum LP7109, and 1.0 × 10(10) cfu/g of Lactobacillus casei LC3200 at a combined rate of 1.3 × 10(5) cfu/g of fresh forage (IN) in mini and Ag-Bag (Ag-Bag Int. Ltd., Warrenton, OR) silos. Silages from the mini silos were assessed for the effect of inoculation on fermentation characteristics and aerobic stability, whereas silages from Ag-Bags were used to formulate 2 barley silage-based total mixed rations (UN and IN) that were fed to growing feedlot steers for 112 d. The IN silage exhibited a homolactic fermentation during the first 7 d of ensiling as reflected by an increased (P ≤ 0.02) lactic acid concentration and an accelerated rate (P < 0.01) of pH decline. Thereafter, fermentation of IN silage became more heterolactic, resulting in greater concentrations of acetic acid (P < 0.01) and pH (P < 0.01) but less (P < 0.01) lactic acid than UN silage. Inoculation did not affect DM losses (P = 0.52) from mini silos. The IN silage remained stable during 21 d, but temperature and yeasts counts in the UN silage increased after 5 d of aerobic exposure. Growing steers fed the IN silage diet had superior (P = 0.03) feed conversion efficiency compared with those fed UN silage. Inoculation of whole-crop barley silage with a mixed culture of homolactic lactic acid-producing bacteria and FAE-producing L. buchneri at ensiling changed fermentation from a homolactic to a heterolactic form during ensiling and improved aerobic stability of the silage and efficiency of BW gain of growing feedlot steers.     

Effects of hybrid and bacterial inoculation on fermentation quality and fatty acid profile of barley silage

This study estimated the effects of hybrid and bacterial inoculant on fermentation quality and fatty acid profile of barley silages. Yuyeon (Silkless) and Youngyang (Silking) barley hybrids were harvested at 24.9 and 27.1% dry matter, respectively, and chopped to 10 cm lengths. Each hybrid was treated with or without an inoculant (2 × 10⁴ colony‐forming units/g of Lactobacillus plantarum). A total of 48 silos were prepared in an experiment with a 2 × 2 (hybrid × inoculant) treatment arrangement with four replications and three ensiling durations (2, 7 and 100 days). After 100 days of ensiling, Yuyeon silage had higher (P < 0.05) in vitro dry matter digestibility and C18:3n‐3 than Youngyang silage. Youngyang silage had higher (P < 0.05) acetic acid and C18:2n‐6 than Yuyeon silage. Inoculation reduced the C18:3n‐3 concentration of both hybrids and increased (P < 0.05) the C18:2n‐6 of Youngyang. However, fermentation quality was not improved by the inoculant. These results indicate that Yuyeon hybrid might have better potential benefits on animal performances due to its smooth awn and silkless nature, and higher in vitro dry matter digestibility. Its higher C18:3n‐3 would be better for improving fatty acid profile of meat or milk than Youngyang hybrid.     

Study on the bacterial community structure and fermentation characteristics of fresh and ensiled paper mulberry

Two experiments were conducted to investigate the bacterial community of fresh and ensiled paper mulberry prepared with or without lactic acid bacteria (LAB) inoculants in South China. In Experiment 1, the bacterial community, chemical composition, and fermentation products of paper mulberry were analyzed. The results showed that fresh paper mulberry had high crude protein content, buffering capacity value, and amounts of uncultured bacteria. Ensiled paper mulberry showed poor fermentation with high pH value, ammonia–N content, and butyric acid content. In addition, Enterobacter was the dominant genus in silage, followed by Lactobacillus and Enterococcus. Water-soluble carbohydrates, ammonia–N, propionic acid, pH, and lactic acid (LA) were the main factors affecting bacterial community of silage. In Experiment 2, the BP17 (Lactobacillus plantarum) from natural fermented paper mulberry silage and two commercial inoculants (Silage-help [SH] and Chikuso-1 [CH]) were used as additives. Compared with other treatments, BP17 inoculant decreased (p < 0.05) pH and ammonia–N content and increased (p < 0.05) LA content of silage. Inoculation of BP17 also increased the dominance of desirable Lactobacillus and inhibited the growth of harmful bacteria in silage. These results confirmed that paper mulberry could be ensiled and epiphytic LAB inoculant can improve its fermentation quality.     

The effects of wilting and storage temperatures on the fermentation quality and aerobic stability of stylo silage

In order to clarify the ensiling characteristics of stylo (Stylosanthes guianensis Swartz), the effects of wilting (no wilting, light wilting and heavy wilting) and storage temperatures (10°C, 20°C, 30°C and 40°C) on the fermentation quality and aerobic stability of stylo silage were investigated. Wilting had no significant influence on the contents of crude protein, ether extract and acid detergent fiber, and numbers of lactic acid bacteria, aerobic bacteria, yeasts and mold (P > 0.05). Heavy wilted material, wilted for 12 h, had higher neutral detergent fiber content and lower water‐soluble carbohydrate content than unwilted and light wilted materials (P < 0.05). Wilting and storage temperatures had significant effects on pH value, acetic acid, butyric acid and NH₃‐N contents of stylo silage (P < 0.01 or P < 0.05). Wilting tended to reduce acetic acid and NH₃‐N contents and improve the fermentation quality of stylo silage. In all the silages, no wilting silage ensiled at 30°C had the highest butyric acid content (P < 0.05). High temperature of 40°C markedly restricted the growth of lactic acid bacteria and aerobic bacteria in silage, irrespective of wilting. The wilted silage or silage stored at low temperature had poor aerobic stability.     

添加乳酸菌和菠萝皮对柱花草青贮品质的影响

柱花草是热带、亚热带的优质豆科牧草,蛋白含量高、营养品质好,为促进柱花草的加工利用,本试验研究了添加不同乳酸菌和菠萝皮对其青贮发酵品质和有氧稳定性的影响。青贮处理为CK(对照)、LQ(青贮宝)、LF(发酵乳杆菌)、LP(植物乳杆菌)、LS(鼠李糖乳杆菌)、B(20%菠萝皮)、BLQ(B+LQ)、BLF(B+LF)、BLP(B+LP)、BLS(B+LS)。添加处理后青贮60 d进行分析。结果表明,柱花草含有较少的可溶性碳水化合物和乳酸菌,自然青贮其pH超过5.0,发酵品质差;所有添加物都显著降低pH、增加乳酸含量(P＜0.05),明显改善了柱花草青贮料的发酵品质。单独添加菠萝皮的丁酸和NH₃-N含量显著高于所有单独添加乳酸菌(P＜0.05),pH与LP以外的其他3种乳酸菌差异不显著(P＞0.05)。除LP的乙酸含量较高,丁酸含量较低外,4种乳酸菌对其他各个发酵指标的影响没有显著差异(P＞0.05)。本试验所用4种乳酸菌与菠萝皮混合添加,都进一步改善了柱花草青贮料的发酵品质,特别是BLP的青贮效果最佳,其pH值、乙酸和NH₃-N含量低,乳酸含量及乳酸与乙酸比高。青贮袋开封后,包括对照在内的所有青贮料的有氧稳定性均较佳。     

添加糖蜜和乙酸对西藏发酵全混合日粮青贮发酵品质及有氧稳定性影响

为研究乙酸和糖蜜对发酵全混合日粮(FTMR)品质及有氧稳定性的影响,试验以全混合日粮(TMR)为发酵原料,设对照组、乙酸(A)、糖蜜(M)、乙酸和糖蜜组合添加(AM)4个处理,发酵45 d后分析FTMR的发酵品质,同时将所有FTMR暴露到空气中,分别在第6,9和12天取样评定其有氧稳定性。结果表明,与对照相比,A和AM组降低了乳酸含量(P>0.05),各组仅检测到微量的丙酸、少量的丁酸和较低的氨态氮/总氮,表明各组FTMR发酵品质均良好。有氧暴露6 d后,各组乳酸、乙酸和水溶性碳水化合物含量均呈不同程度的下降,对照和M组pH值在第12 天显著(P<0.05)上升至5.70和6.50,具有较高的氨态氮/总氮和酵母菌数量。而A和AM组乳酸含量均呈先上升后下降的变化趋势,且好氧性微生物和酵母菌数量在整个有氧暴露的过程中始终维持在较低水平,有氧暴露12 d后pH值仍维持在4.50左右,延长了有氧稳定时间。综合考虑,为了获得品质优良的FTMR饲料,可在TMR中添加0.3%乙酸,既不影响发酵品质,也可提高其有氧稳定性。     

Fermentation and microbial population dynamics during the ensiling of native grass and subsequent exposure to air

To study the microbial population and fermentation dynamics of large needlegrass (LN) and Chinese leymus (CL) during ensiling and subsequent exposure to air, silages were sampled and analyzed using culture‐based techniques and denaturing gradient gel electrophoresis (DGGE). A total of 112 lactic acid bacteria (LAB) strains were isolated and identified using the 16S rRNA sequencing method. Lactic acid was not detected in the first 20 days in LN silage and the pH decreased to 6.13 after 45 days of ensiling. The temperature of the LN silage increased after approximately 30 h of air exposure and the CL silage showed a slight temperature variation. Enterococcus spp. were mainly present in LN silage. The proportion of Lactobacillus brevis in CL silage increased after exposure to air. LN silage with a higher proportion of Enterococcus spp. and propionic acid concentration did not show higher fermentation quality or aerobic stability than CL silage, which had a higher concentration of acetic acid, butyric acid and increased proportion of L. brevis after exposure to air.     

Effects of ethanol,molasses and Lactobacillus plantarum on the fermentation quality,in vitro digestibility and aerobic stability of total mixed ration silages in the Tibetan plateau of China

In Tibet, it is common practice to make and relocate total mixed ration (TMR) silages before feeding due to the uneven distribution of forages temporally and spatially. This study was conducted to investigate the effects of Lactobacillus plantarum (L), molasses (M) or ethanol (E) on the fermentation quality and aerobic stability of local adaptive TMR silage. After 45 days of ensiling, pH and ammonia nitrogen in inoculated TMR silages were significantly lower than control. During the first 6 days of the aerobic exposure test, a small fluctuation in lactic acid concentration for all TMR silages was observed, and then silages with ethanol continued this trend, while lactic acid in silage without ethanol sharply decreased until the end of the aerobic exposure period. Meanwhile, pH gradually increased along the aerobic exposure; silages treated with ethanol showed lower pH after 9 days of aerobic exposure. The population of yeast gradually increased during 6 days of aerobic exposure, after that an accelerated rise was observed in TMR silages without ethanol. The combinational beneficial effect of L. plantarum and ethanol was found in combined addition of ethanol and Lactobacillus plantarum silages (EL), indicated by intermediate fermentation quality and higher aerobic stability.     

Characterization and application of lactic acid bacteria for tropical silage preparation

Strains TH 14, TH 21 and TH 64 were isolated from tropical silages, namely corn stover, sugar cane top and rice straw, respectively, prepared in Thailand. These strains were selected by low pH growth range and high lactic acid‐producing ability, similar to some commercial inoculants. Based on the analysis of 16S ribosomal RNA gene sequence and DNA‐DNA relatedness, strain TH 14 was identified as Lactobacillus casei, and strains TH 21 and TH 64 were identified as L. plantarum. Strains TH 14, TH 21, TH 64 and two commercial inoculants, CH (L. plantarum) and SN (L. rhamnosus), were used as additives to fresh and wilted purple Guinea and sorghum silages prepared using a small‐scale fermentation method. The number of epiphytic lactic acid bacteria (LAB) in the forages before ensilage was relatively low but the numbers of coliform and aerobic bacteria were higher. Sorghum silages at 30 days of fermentation were all well preserved with low pH (3.56) and high lactic acid production (72.86 g/kg dry matter). Purple Guinea silage inoculated with LAB exhibited reduced count levels of aerobic and coliform bacteria, lower pH, butyric acid and ammonia nitrogen and increased lactic acid concentration, compared with the control. Strain TH 14 more effectively improved lactic acid production compared with inoculants and other strains. © 2016 Japanese Society of Animal Science     

Lactobacillus parafarraginis ZH1 producing anti‐yeast substances to improve the aerobic stability of silage

Enhancing the aerobic stability of silage is very important in silage production. The objective of this study was to compare the roles of a new bacterial strain Lactobacillus parafarraginis ZH1 with Lactobacillus plantarum Chikuso‐1 (LP) and Lactobacillus buchneri NCIMB 40788 (LB) in improving the aerobic stability of oat silage and identify the anti‐yeast substances produced by them. After ensiled for 45 days, either inoculated silages or control silage were of pH values lower than 4.2. The control and LP inoculated silage had poorer aerobic stability than LB and ZH1 inoculated ones (p < 0.05). ZH1 inoculated silage produced more acetic acid, benzoic acid and hexadecanoic acid than LB inoculated one and had the best aerobic stability (p < 0.05). In MRS medium, strain ZH1 produced more hexadecanoic acid than LP and LB strains, more benzoic acid than strain LP (p < 0.05), and the equal amount of benzoic acid to LB (p > 0.05). In addition, benzoic acid and hexadecanoic acid had low minimal inhibitory concentrations to target yeasts in the pure culture. In conclusion, L. parafarraginis ZH1 had stronger anti‐yeast potential and more effectively improved the aerobic stability of silage than other strains used in this study.     

Effect of microbial inoculants on the fermentation characteristics,nutritive value,and in vitro digestibility of various forages

This study was aimed to examine the characteristics of three isolated lactic acid bacteria (LAB) strains (HG24, M1, and TG1), and to evaluate their effects on fermentation characteristics, nutritive value, and in vitro digestibility in a variety of substrates. The experiments were conducted with Italian ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schred.), and oat (Avena sativa L.) in laboratory silo (1 L) for ensiling 30 days. All the treated silages had significantly (p < 0.05) higher in vitro dry matter digestibility (IVDMD), and lower undesirable microorganism populations compared with controls. In Italian ryegrass and oat silages, all the inoculants improved the fermentation quality, evidenced by distinctly (p < 0.05) higher LA contents and ratios of LA to acetic acid, and lower pH, butyric acid and ammonia nitrogen contents. Strains HG24 and commercial inoculant G (Lactobacillus plantarum MTD‐1) performed better than strains M1 and TG1, indicated by obviously (p < 0.05) higher LA contents, LAB numbers, and IVDMD. In tall fescue silage, all the isolated LAB strains (HG24, M1 and TG1) markedly (p < 0.05) increased IVDMD compared with strain G. Strain HG24 is recommended as a good LAB inoculant for ensiling in various forages.