Effects of storage temperature and ensiling period on fermentation products, aerobic stability and microbial communities of total mixed ration silage

Can dietary fermented total mixed ration additives biological and chemical improve digestibility, performance, and rumen fermentation in ruminants?

The quantity and quality of animal feed are important factors for efficient and profitable animal farming. Feed ingredients and supplementation with high-density energy and nitrogen would be potentially useful on the farm. The new approach to feeding has shifted from animal-based diets to more readily fermentable feedstuffs in ruminants to meet the increased production of high-yielding animals. These methods encourage the use of fermented total mixed ration (FTMR). An advantage of feeding FTMR as opposed to total mixed ration (TMR) is the opportunity for a development alternative to efficiently handle ruminant diets. FTMR is a method to promote progressive nutrient utilization, extend the preservation of feed by preventing spoilage, and reduce anti-nutritive substances in feeds. Ruminal protein and starch degradability were increased due to proteolysis during storage by ruminants fed ensiled rations. The results found that FTMR can reduce the pH level and increase the lactic acid content of ensiled materials, which results in better quality feed and longer storage times. In addition, it can increase dry matter intake, growth rate, and milk production when compared with TMR. It was shown that the use of FTMR diet was effective for animal production. However, FTMR was rapidly spoiled when exposed to air or feed-out, particularly in hot and humid climates, resulting in a decrease in lactic acid concentration, an increase in pH, and the loss of nutrients. Thus, the appropriate method for enhancing the quality of FTMR should be considered.

The Energy Contents of Broken Rice for Lactating Dairy Cows

This study aimed to evaluate (1) the net energy for lactation of broken rice in dairy cows and (2) the effects of broken rice substituting in diets on feed intake, nutrient energy utilization, and milk production. An energy metabolism experiment was conducted using a respiration chamber system in four multiparous Holstein crossbred cows (88.6% Holstein × 11.4% Native Thai; body weight of 438 ± 16.0 kg; 70 ± 31 days in milk) according to a 4 × 4 Latin square design with four 21-d periods. The four dietary treatments included a basal diet substitution with broken rice at 0%, 12%, 24%, and 36%. Increasing the substitution rate of broken rice in the diet resulted in unaffected feed intake, milk yield and composition, and energy balance (p > 0.05); however, a linear increase in the digestibility of dry matter, organic matter, and neutral detergent fiber (p < 0.05). The estimated net energy for lactation of broken rice was 8.68 MJ/kg. The net energy requirement for maintenance was estimated at 504 kJ/kg of metabolic body weight. Our results indicated that broken rice is a good energy-feed resource and that increasing the proportion in the diet up to 36% had no adverse effect on dairy cows' production performance.

Effect of Storage Period on the Fermentation Profile and Bacterial Community of Silage Prepared with Alfalfa, Whole-Plant Corn and Their Mixture

This study aimed to investigate the impact of storage time on the bacterial community and fermentation profile of silage prepared with alfalfa, whole-plant corn, and their mixture. Fresh alfalfa and whole-plant corn were chopped and combined in fresh weight ratios of 1:0 (alfalfa, control), 0.8:0.2 (M1), 0.6:0.4 (M2), and 0:1 (corn). Three silos of each treatment were analyzed after 30, 60, and 90 d of storage. With storage time, pH, acetic acid, propionic acid, butyric acid, and ammonia nitrogen levels increased in alfalfa silage (p < 0.01), whereas lactic acid level decreased (p < 0.01). Compared to alfalfa silage, M1, M2, and corn silages were better fermented and more stable during storage. The dominant bacteria in M1, M2, and corn silages shifted significantly from L. plantarum, L. buchneri, and L. brevis to L. acetotolerans and L. buchneri during 30 to 60–90 d of storage, and storage time decreased the bacterial diversity of these silages. In conclusion, storage time significantly decreased the fermentation quality of alfalfa silage and remarkably optimized the bacterial community structure of well-fermented M1, M2, and corn silages. Alfalfa should be ensiled with at least 20% whole-plant corn to improve silage fermentation quality and storage stability.

Effects of wilting during a cloudy day and storage temperature on the fermentation quality and microbial community of Napier grass silage

BACKGROUND

Wilting affects the chemical compositions and epiphytic microorganisms of grasses to some extent, thereby influencing the fermentation characteristics of silage. The present study investigated the effects of wilting during a cloudy day and ensiling temperature (20, 30 and 40 °C) on the fermentation of Napier grass (Pennisetum purpureum).

RESULTS

Wilting during a cloudy day significantly decreased the water-soluble carbohydrate content (P < 0.05) and significantly increased pH, counts of lactic acid bacteria and aerobic bacteria in grass (P < 0.05). Wilting increased the relative abundance of the Enterobacteriaceae family, as well as genera such as Acinetobacter, Pantoea and Lactococcus, and also decreased that of Sphingomonas and Methylobacterium, in fresh grass. Although ensiling increased the relative abundance of Lactobacillus, a Enterobacteriaceae genus was the dominant microorganism in Napier grass before ensiling and after ensiling. Wilting increased pH, acetic acid, butyric acid and NH₃ -N contents, and also reduced the lactic acid content, of Napier grass silage. Additionally, the fermentation quality of silages at 30 °C was poorer, irrespective of wilting, as indicated by high pH, high butyric acid and NH₃ -N contents, high relative abundance of Clostridium and Bifidobacterium, and a low lactic acid content. Ensiling at 40 °C enhanced lactic acid bacteria fermentation and also suppressed clostridial fermentation and the growth of microorganisms in silages.

CONCLUSION

Napier grass should be ensiled immediately after being harvested during a cloudy day and ensiling at 30 °C should be avoided to prevent poor fermentation. © 2022 Society of Chemical Industry.

Bacterial and fungal microbiota of total mixed ration silage stored at various temperatures

AIMS

To obtain insights into how bacterial and fungal microbiota and fermentation products composition are affected by storage temperature for TMR silage, which can be manufactured year-round.

METHODS AND RESULTS

TMR silage was stored at 10°C, 25°C, ambient temperature (AT; 20-35°C), and 40°C. Lactic acid production was delayed when stored at 10°C, and acid production stagnated after 2 weeks when stored at 40°C. The patterns of acetic acid and ethanol production were inversely related, with ethanol production promoted at 10°C and 25°C and acetic acid production promoted at AT and 40°C. The bacterial diversity was reduced in TMR silage with high lactic acid and acetic acid content, and the fungal diversity was reduced in TMR silage with high ethanol content.

CONCLUSIONS

The intensity of lactic acid production was accounted for by the high abundance of Lactobacillus, and its stagnated production at a substantially high storage temperature was related to an increased abundance of Bacillus. The enhanced production of acetic acid or ethanol can be explained by differences in the fungal microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The integrated analysis of bacterial and fungal microbiota can provide in-depth insights into the impact of storage temperature on TMR silage fermentation.

Effects of LAB Inoculants on the Fermentation Quality, Chemical Composition, and Bacterial Community of Oat Silage on the Qinghai-Tibetan Plateau

Lactic acid bacteria (LAB) have been proposed for the control of undesirable fermentation and, subsequently, aerobic deterioration due to their ability to produce antimicrobial metabolites in silage mass. To investigate the effect of specific LAB on the silage fermentation characteristics and bacterial community composition of oat in cold regions, silages were treated without (control) or with three LAB strains (LB, Lentilactobacillus buchneri; nLP, low temperature tolerant Lactiplantibacillus plantarum; pLP, phenyllactic acid-producing Lactiplantibacillus plantarum), and then stored at ambient temperature (−2.63 ± 5.47−14.29 ± 5.48 °C) for 30, 60, and 90 days. Compared with control, inoculation of LAB decreased the final pH value, butyric acid content, ammonia-N of total N and dry matter loss of silage. Treatments with nLP and pLP increased (p < 0.05) lactic acid content, whereas LB increased (p < 0.05) acetic acid content of silage. Lactiplantibacillus and Leuconostoc dominated in the silages with relative abundance of 68.29−96.63%. A prolonged storage period enhanced the growth of Leuconostoc in pLP-treated silage. In addition, pLP increased (p < 0.05) the aerobic stability of silage as compared with nLP. In conclusion, inoculation of LAB improved silage fermentation and/or delayed aerobic deterioration by shifting bacterial community composition during ensiling. Phenyllactic acid-producing Lactiplantibacillusplantarum as an inoculant exhibited potential for high quality silage production.

Effect of Novel Aspergillus and Neurospora species-Based Additive on Ensiling Parameters and Biomethane Potential of Sugar Beet Leaves

Research on additives that improve the quality of silages for an enhanced and sustainable biogas production are limited in the literature. Frequently used additives such as lactic acid bacteria enhance the quality of silages but have no significant effect on biogas yield. This study investigated the effect of a new enzymatic additive on the quality of ensiling and BMP of sugar beet leaves. Sugar beet leaves were ensiled with and without the additive (Aspergillus- and Neurospora-based additive) in ratios of 50:1 (A50:1), 150:1 (B150:1), and 500:1 (C500:1) (gsubstrate/gadditive) for 370 days at ambient temperature. Results showed that silages with additive had lower yeast activity and increased biodegradability compared to silages without additive (control). The additive increased the BMP by 45.35%, 24.23%, and 21.69% in silages A50:1, B150:1, and C500:1 respectively, compared to silages without additive (control). Although the novel enzyme is in its early stage, the results indicate that it has a potential for practical application at an additive to substrate ratio (g/g) of 1:50. The use of sugar beet leaves and the novel enzyme for biogas production forms part of the circular economy since it involves the use of wastes for clean energy production.

Effect of feeding a diet comprised of various corn silages inclusion with peanut vine or wheat straw on performance, digestion, serum parameters and meat nutrients in finishing beef cattle

Objective

The objective of this study was to compare the feeding value, meat nutrients and associative effects of a diet comprised of various corn silages inclusion with peanut vine or wheat straw in finishing beef cattle.

Methods

One hundred and eighty Simmental crossbred beef steers were blocked and assigned to the follow treatments: i) whole plant corn silage-based diet (control, WPCS), ii) mixed forages-based diet (replacing a portion of corn silage with wheat straw, WPCSW), iii) corn stalklage-based diet (CS), and iv) sweet corn stalklage-based diet (SCS). Each group consisted of 5 repeated pens with 9 steers/pen. The diets were formulated to be isonitrogenous and isoenergetic with same forage to concentrate ratio. Experimental diets were fed for 90 d.

Results

The effective ruminal degradability of dry matter and crude protein were highest for WPCS diet (p<0.05), for neutral detergent fiber was highest in SCS diet (p<0.05). The average daily gain was greater for cattle offered the WPCS diet, intermediate with WPCSW and SCS and lowest with CS (p<0.001). The concentration of non-esterified fatty acid in serum was higher for steers fed with CS and SCS diets than those offered WPCS and WPCSW steers (p<0.001). The treatments did not affect the general nutritional contents and amino acids composition of Longissimus dorsi of steers (p>0.05).

Conclusion

The corn silage-based diet exhibited the highest feeding value. The sweet corn stalklage and wheat straw as an alternative to corn silage offered to beef cattle had limited influence on feeding value and meat nutrients. However, the value of a corn stalklage-based diet was relatively poor. To sum up, when the high quality forage resources, such as corn silage, are in short supply, or the growth rate of beef cattle decreases in the later finishing period, the sweet stalklage and wheat straw could be used as a cheaper alternative in feedlot cattle diet without sharp reducing economic benefits.

Improvement of Fermentation Quality in the Fermented Total Mixed Ration with Oat Silage

The use of the fermented total mixed ration (FTMR) is a promising approach for the preservation of homogeneous feed, but changes during fermentation and links with the bacterial community of FTMR are not fully understood. This study investigated the effects of adding oat silage (OS) to the fermented total mixed ration (FTMR) in terms of fermentation, chemical composition, and the bacterial community. The fermentation quality of FTMR with 22% OS was greatly improved, as demonstrated by decreases in the butyric acid concentration, a lower lactic acid/acetic acid ratio, a larger population of lactic acid bacteria (LAB), and quicker spoilage yeast death. Further examination of the effects of various ensiling days on nutritive values showed stable crude protein and nonprotein nitrogen (NPN) contents. The concentrations of acetic acid, propionic acid, and ammonia-nitrogen (NH₃-N) were increased following all FTMR treatments after 15 d, while the concentration of water-soluble carbohydrates (WSC) was decreased. More heterofermentative LAB, such as Lentilactobacillus buchneri, Lentilactobacillus brevis, and Companilactobacillus versmoldensis were found after adding 11% and 22% OS. Moreover, the addition of 22% OS caused a marked increase in both bacterial richness and diversity, dominated by the Lactobacillus genus complex. Among species of the Lactobacillus genus complex, the occurrence of Loigolactobacillus coryniformis was positively correlated with lactic acid, NPN, and NH₃-N concentrations, suggesting its potential role in altering the fermentation profiles.

Broken rice in a fermented total mixed ration improves carcass and marbling quality in fattened beef cattle

Objective

This study aimed to determine the effects of replacing cassava chips with broken rice in a fermented total mixed ration diet on silage quality, feed intake, ruminal fermentation, growth performance, and carcass characteristics in the final phase of fattening beef cattle.

Methods

Eighteen Charolais-Thai native crossbred steers (average initial body weight: 609.4±46 kg; average age 31.6 mo) were subjected to three ad libitum dietary regimes and were maintained in individual pens for 90 d before slaughter. The experimental design was a randomized complete block design by initial age and body weight with six replicates. The dietary regimens used different proportions of broken rice (0%, 16%, and 32% [w/w] of dry matter [DM]) instead of cassava chips in a fermented total mixed ration. All dietary treatments were evaluated for in vitro gas production and tested in in vivo feeding trials.

Results

The in vitro experiments indicated that organic matter from broken rice was significantly more digestible than that from a cassava-based diet (p<0.05). Silage quality, nutrient intake, ruminal fermentation characteristics, carcass fat thickness, and marbling score substantially differed among treatments. The ruminal total volatile fatty acids, propionate concentration, dietary protein intake, and digestibility increased linearly (p<0.05) with broken rice, whereas acetate concentration and the acetate:propionate ratio decreased linearly (p<0.05) with broken rice (added up to 32 g/kg DM). Broken rice did not influence plasma metabolite levels or growth performance (p>0.05). However, the marbling score increased, and the carcass characteristics improved with broken rice.

Conclusion

Substitution of cassava chips with broken rice in beef cattle diets may improve fattened beef carcass quality because broken rice increases rumen fermentation, fatty acid biosynthesis, and metabolic energy supply.

Improving sugarcane bagasse quality as ruminant feed with Lactobacillus, cellulase, and molasses

The objective of the study was to evaluate the effects of Lactobacillus, cellulase, and molasses on chemical composition, fermentation qualities, and microorganism count of sugarcane bagasse silage after 30-days fermentation. The treatments were arranged according to a factorial arrangement (2 × 2 × 2) + 1, in a complete randomized design. The first factor consisted of two levels of Lactobacillus casei TH14 (TH14, 0 and 0.05 g/kg fresh matter; the second factor consisted of two levels of cellulase enzyme (C, 0 and 10⁴ U/kg fresh matter); and the third factor consisted of two levels of molasses (M, 0 and 5 g/ 100 mL distilled water). A treatment (+1) referred to the use of rice straw without any treatments. The result showed that dry matter increased by 4% and neutral detergent fiber decreased by 2% of sugarcane bagasse when ensiled as a combination of additives as compared to untreated sugarcane bagasse. The pH and ammonia nitrogen were significantly dropped to 3.5 and 2.3 g/kg dry matter. Furthermore, lactic acid was increased by 64% when compared to untreated sugarcane bagasse, respectively. Lactic acid bacteria count was increased by 28% as compared to untreated sugarcane bagasse. Based on this experiment, fermenting with L. casei TH14, cellulase, and molasses in combination resulted in the promotion of the best qualities of sugarcane bagasse silage.

The Bacterial Community Associated with the Amarillo Zamorano Maize (Zea mays) Landrace Silage Process

Maize silage is used in the diet of dairy cows, with suitable results in milk yield. In this study, the composition and diversity of the bacterial communities of the silage process of Amarillo Zamorano (AZ) Mexican maize landrace with relation to the Antilope (A) commercial hybrid are described. From both types of maize, seeds were sown in experimental plots, plants harvested at the reproductive stage, chopped, and packed in laboratory micro-silos. Physicochemical parameters were evaluated, and DNA was extracted from the juice in the micro-silos. The bacterial communities were analyzed by next-generation sequencing (NGS) of seven hypervariable regions of the 16S rRNA gene. The composition of both bacterial communities was dominated by Lactobacillales and Enterobacteriales, Lactobacillales mainly in A silage and Enterobacteriales in AZ silage; as well, the core bacterial community of both silages comprises 212 operational taxonomic units (OTUs). Sugar concentration showed the highest number of significant associations with OTUs of different phyla. The structure of the bacterial communities was different in both silage fermentation processes, showing that AZ silage has a shorter fermentation process than A silage. In addition, NGS demonstrated the effect of the type of maize and local conditions on silage fermentation and contributed to potential strategies to improve the quality of AZ silage.

Effects of Lactobacillus plantarum additive and temperature on the ensiling quality and microbial community dynamics of cauliflower leaf silages

In order to enable rapid disposal and proper preservation of discarded vegetable for waste valorization, ensiling was employed to preserve cauliflower leaves for 30 days at different temperatures (20 ~ 45 °C) with and without the addition of Lactobacillus plantarum L8. The L. plantarum inoculant reduced dry matter (DM) loss and enhanced the preservation of protein and soluble carbohydrate while decreasing pH and ammonia nitrogen content. The silages at 35 °C exhibited the best fermentation profile characterized by the highest lactic acid content (185 g·kg^-1 DM) and the lowest pH (4.08) and ammonia nitrogen content (37.6 g·kg^-1 total nitrogen) with L. plantarum inoculation. The presence of exogenous L. plantarum improved the silage fermentation, enriched Lactobacillus and Weissella, and reduced the microbial richness/diversity, resulting in efficient lactic acid fermentation, especially at 30 and 35 °C. Moreover, the microbial community dynamics was correlated with the chemical compositions and fermentation metabolites in silages.

Ensiling of whole-plant hybrid pennisetum with natamycin and Lactobacillus plantarum impacts on fermentation characteristics and meta-genomic microbial community at low temperature

BACKGROUND

The aim of the current research was to clarify the impacts of the ensiling of whole-plant hybrid pennisetum with natamycin and Lactobacillus plantarum on fermentation characteristics and the meta-genomic microbial community at low temperatures.

RESULTS

During the ensiling process, lactic acid (LA) and lactic acid bacteria (LAB) significantly (P < 0.05) increased and acetic acid (AA), water-soluble carbohydrate (WSC), ammonia total nitrogen (NH3-N), and yeast significantly (P < 0.05) reduced in treatments as compared to controls. Different treatments and different ensiling days led to variations in the bacterial community at family and genus levels. The family Lactobacillaceae and genera Lactobacillus and Pediococcus are dominant communities in treatment silage. The family and genus levels bacterial ecology and fermentation quality were analyzed by principal component analysis (PCA). The PCO1, and PCO2 can be explained by 10.81% and 72.14% of the whole variance regularly, similarly in PCO1 and PCO2 can be explained 24.23% and 52.06% regularly. The core bacterial micro-biome operational taxonomic unit (OTU) numbers increased in treatments, as compared to controls, on different hybrid pennisetum ensiling days.

CONCLUSIONS

The inoculation of L. plantarum alone and combined with natamycin influenced the fermentation quality and reduced undesirable microorganisms during the fermentation of hybrid pennisetum silage. Natamycin alone did not significantly enhance the concentration of organic acid but numerically enhanced in treatments group as compared to control. © 2020 Society of Chemical Industry.

Effects of natamycin and Lactobacillus plantarum on the chemical composition, microbial community, and aerobic stability of Hybrid pennisetum at different temperatures

This study evaluated the effects of natamycin and Lactobacillus plantarum on the chemical composition, microbial community, and aerobic stability of Hybrid pennisetum at different temperatures. Different concentrations of natamycin (0.50 g L⁻¹, 1.00 g L⁻¹, and 1.50 mg L⁻¹) significantly (p > 0.05) reduced the growth of undesirable microorganisms. During the ensiling periods the pH, ammonia nitrogen (NH₃–N), acetic acid (AA), butyric acid (BA), aerobic bacteria (AB), and yeast were significantly (p > 0.05) reduced, while the lactic acid and lactic acid bacteria were significantly (p < 0.05) influenced in the SLP and SLNP groups as compared to the SP and SNP groups at high temperature (29–30 °C). During air exposure, water-soluble carbohydrate, ammonia nitrogen (NH₃–N), lactic acid (LA), and acetic acid (AA) were not influenced, while pH and aerobic bacteria were significantly (p < 0.05) enhanced after three days (72 hours) of air exposure, and lactic acid bacteria were significantly (p > 0.05) reduced at ambient temperature (9–10 °C). It is concluded that the addition of L. plantarum CICC 20765 alone and in combination with natamycin reduced the content of AA, pH, NH₃–N, BA, and undesirable microbial community, and enhanced the chemical composition, fermentation quality, and air exposure. Natamycin alone did not significantly enhance the organic acid profile but improved the air exposure. Furthermore, more effort is needed to evaluate the effects on silage preservation on a large scale and on animal performance.

The inoculation of L. plantarum and natamycin influenced the fermentation quality. Natamycin and L. plantarum reduced the undesirable microbial community. During ensiling process, the LA and LABs was significantly enhanced.

Ferulic acid esterase-producing lactic acid bacteria and cellulase pretreatments of corn stalk silage at two different temperatures: Ensiling characteristics, carbohydrates composition and enzymatic saccharification

The effects of Acremonium cellulase and L. plantarum A1 with ferulic acid esterase activity on corn stalk silage fermentation characteristics, carbohydrate composition and enzymatic saccharification were studied at 25 and 40 °C, respectively. Corn stalk was ensiled without additive (C), Acremonium cellulase (AC), L. plantarum A1 (Lp) and AC + Lp for 60 days. Pretreatment with Lp or AC + Lp promoted the better silage fermentation and the degradation of lignocellulose as indicated by high lactic acid and low pH and lignocellulose content compared to control silages at 25 °C. AC + Lp performed better in reducing lignocellulose and DM loss. In addition, Lp alone enhanced enzymatic saccharification of corn stalk silage. However, the influence of L. plantarum A1 on corn stalk silage was not obvious at 40 °C. Corn stalk ensiled with combined additive is a suitable pretreatment method for subsequent biofuel production at 25 °C, but addition of Acremonium cellulase alone at 40 °C may be a promising method.

Chemical composition, fermentative losses, and microbial counts of total mixed ration silages inoculated with different Lactobacillus species

The objective of this study was to evaluate the effects of Lactobacillus inoculants on fermentation, losses, and aerobic stability of a total mixed ration (TMR) silage. A TMR, formulated to meet the requirements of dairy cows producing 25 kg of milk/d, was applied with the following treatments prior to ensiling: 1) Control (CON), 2) Lactobacillus buchneri (105 cfu/g of fresh forage; LB), and 3) Lactobacillus plantarum (105 cfu/g of fresh forage; LP). TMR silages were ensiled for 15 and 60 d in silos equipped with an apparatus for determination of gravimetric DM, gas, and effluent losses. The experiment was performed in a complete randomized design with a 3 × 2 factorial arrangement of the treatments, with 5 replicates per treatment. Chemical changes, microbial counts, fermentation profile, and aerobic stability were measured after opening the silos. Data were submitted to ANOVA, and means were compared by Tukey and T-test and statistical significance was declared at P ≤ 0.05. After 15 d of ensiling, the inclusion of inoculant decreased NDF (P < 0.05) and butyric acid concentrations (P < 0.05) in TMR. LP had the lowest aerobic stability (P < 0.05) and the greatest loss of DM (P < 0.03). Ensiling for 60 d increased ammonia nitrogen (NH3-N), lactic acid bacteria (LAB), aerobic stability, and concentrations of lactic and acetic acid (P < 0.01) and lowered (P < 0.02) total fermentation losses compared to 15 d across all treatments. After 60 d of ensiling, LP lowered pH to the greatest extent. Treatment had no effect on concentrations of DM, CP, ADF, ash, and EE, as well as in vitro DM digestibility. In conclusion, inoculants containing LP or LB did not improve fermentation profile, did not prolong the aerobic stability, nor reduced losses. Furthermore, the 15-d ensiling period was insufficient for adequate bacterial activity.

Fermentation characteristics, chemical composition and microbial community of tropical forage silage under different temperatures

Objective

In tropical regions, as in temperate regions where seasonality of forage production occurs, well-preserved forage is necessary for animal production during periods of forage shortage. However, the unique climate conditions (hot and humid) and forage characteristics (high moisture content and low soluble carbohydrate) in the tropics make forage preservation more difficult. The current study used natural ensiling of tropical forage as a model to evaluate silage characteristics under different temperatures (28°C and 40°C).

Methods

Four tropical forages (king grass, paspalum, white popinac, and stylo) were ensiled under different temperatures (28°C and 40°C). After ensiling for 30 and 60 days, samples were collected to examine the fermentation quality, chemical composition and microbial community.

Results

High concentrations of acetic acid (ranging from 7.8 to 38.5 g/kg dry matter [DM]) were detected in silages of king grass, paspalum and stylo with relatively low DM (ranging from 23.9% to 30.8% fresh material [FM]) content, acetic acid production was promoted with increased temperature and prolonged ensiling. Small concentrations of organic acid (ranging from 0.3 to 3.1 g/kg DM) were detected in silage of white popinac with high DM content (50.8% FM). The microbial diversity analysis indicated that Cyanobacteria originally dominated the bacterial community for these four tropical forages and was replaced by Lactobacillus and Enterobacter after ensiling.

Conclusion

The results suggested that forage silages under tropical climate conditions showed enhanced acetate fermentation, while high DM materials showed limited fermentation. Lactobacillus and Enterobacter were the most probable genera responsible for tropical silage fermentation.

Effects of homolactic bacterial inoculant on the performance of lactating dairy cows

The objective of this experiment was to determine the effect of applying a homofermentative bacterial inoculant to corn silage on the performance of dairy cows. After harvesting, corn forage was treated with nothing (CON) or with an inoculant containing a mixture of Lactococcus lactis, Lactobacillus plantarum, and Enterococcus faecium at 1.5 × 10⁵ cfu/g of fresh forage (MC; SiloSolve MC, Chr. Hansen A/S, Hørsholm, Denmark). After 186 d of storage in Ag-Bags (A Miller-St. Nazianz Inc., St. Nazianz, WI), silages were fed as part of a total mixed ration containing 55% concentrates, 10% alfalfa hay, and 35% CON or MC corn silage. Sixty early-lactation Holstein dairy cows (30 multiparous and 30 primiparous) housed in a freestall barn with Calan gates (American Calan Inc., Northwood, NH) were assigned to the dietary treatments from 20 to 100 d in milk. Silage inoculated with MC had a more homofermentative pattern evidenced by greater lactic acid concentration (3.83 vs. 4.48% of DM) and lower concentrations of acetic (2.34 vs. 1.68% of DM) and propionic (0.37 vs. 0.10% of DM) acids and ammonia (9.11 vs. 7.82% of N) for CON and MC, respectively. Dry matter intake (23.1 vs. 23.2 kg/d) did not differ among treatments, but the MC silage had greater apparent digestibility of DM (68.8 vs. 70.8%), which led to greater yields of milk (37.7 vs. 38.5 kg/d), fat-corrected milk (37.6 vs. 38.4 kg/d), milk fat (1.30 vs. 1.33 kg/d), and lactose (1.83 vs. 1.92 kg/d) for CON and MC cows, respectively. Milk from cows fed MC silage had higher lactose (4.86 vs. 4.93%), lower protein (2.93 vs. 2.83%), and similar contents of fat (3.47 vs. 3.44%) compared with CON cows. Feed efficiency (fat-corrected milk/dry matter intake) was not affected by treatment (1.69 vs. 1.72 for CON and MC, respectively). Inoculation of corn silage with the homofermentative inoculant increased digestibility of the total mixed ration and increased milk yield by lactating dairy cows.

Feed intake, digestibility and energy partitioning in beef cattle fed diets with cassava pulp instead of rice straw

Objective

This study was conducted to assess the effects of replacing rice straw with different proportions of cassava pulp on growth performance, feed intake, digestibility, rumen microbial population, energy partitioning and efficiency of metabolizable energy utilization in beef cattle.

Methods

Eighteen yearling Thai native beef cattle (Bos indicus) with an average initial body weight (BW) of 98.3±12.8 kg were allocated to one of three dietary treatments and fed ad libitum for 149 days in a randomized complete block design. Three dietary treatments using different proportions of cassava pulp (100, 300, and 500 g/kg dry matter basis) instead of rice straw as a base in a fermented total mixed ration were applied. Animals were placed in a metabolic pen equipped with a ventilated head box respiration system to determine total digestibility and energy balance.

Results

The average daily weight gain, digestible intake and apparent digestibility of dry matter, organic matter and non-fiber carbohydrate, total protozoa, energy intake, energy retention and energy efficiency increased linearly (p<0.05) with an increasing proportion of cassava pulp in the diet, whereas the three main types of fibrolytic bacteria and energy excretion in the urine (p<0.05) decreased. The metabolizable energy requirement for the maintenance of yearling Thai native cattle, determined by a linear regression analysis, was 399 kJ/kg BW^0.75, with an efficiency of metabolizable energy utilization for growth of 0.86.

Conclusion

Our results demonstrated that increasing the proportion of cassava pulp up to 500 g/kg of dry matter as a base in a fermented total mixed ration is an effective strategy for improving productivity in zebu cattle.

Effect of inoculants and storage temperature on the microbial, chemical and mycotoxin composition of corn silage

Objective

To evaluate the effect of lactic acid bacteria and storage temperature on the microbial, chemical and mycotoxin composition of corn silage.

Methods

Corn was harvested at 32.8% dry matter, and chopped to 1 to 2 cm. The chopped material was subjected to three treatments: i) control (distilled water); ii) 1×10⁶ colony forming units (cfu)/g of Lactobacillus plantarum; iii) 1×10⁶ cfu/g of Pediococcus pentosaceus. Treatments in triplicate were ensiled for 55 d at 20°C, 28°C, and 37°C in 1-L polythene jars following packing to a density of approximately 800 kg/m³ of fresh matter, respectively. At silo opening, microbial populations, fermentation characteristics, nutritive value and mycotoxins of corn silage were determined.

Results

L. plantarum significantly increased yeast number, water soluble carbohydrates, nitrate and deoxynivalenol content, and significantly decreased the ammonia N value in corn silage compared with the control (p<0.05). P. pentosaceus significantly increased lactic acid bacteria and yeast number and content of deoxynivalenol, nivalenol, T-2 toxin and zearalenone, while decreasing mold population and content of nitrate and 3-acetyl-deoxynivalneol in corn silage when stored at 20°C compared to the control (p<0.05). Storage temperature had a significant effect on deoxynivalenol, nivalenol, ochratoxin A, and zearalenone level in corn silage (p<0.05).

Conclusion

Lactobacillus plantarum and Pediococcus pentosaceus did not decrease the contents of mycotoxins or nitrate in corn silage stored at three temperatures.

Fermentation quality and nutritive value of total mixed ration silages based on desert wormwood (Artemisia desertorum Spreng.) combining with early stage corn

This study aimed to investigate the fermentation quality and nutritive value of total mixed ration (TMR) silages based on desert wormwood (DW) combined with early stage corn (ESC) as forage and determine an optimum formula. Desert wormwood and ESC were harvested, chopped, and mixed with other ingredients according to a formula, packed into laboratory silos at densities of 500-550 g/L, and stored in the dark for 60 days. The DW proportions in the forage of TMR were 1, 0.75, 0.50, 0.25 and 0, based on fresh weight. As the proportion of DW decreased, the pH also decreased (P < 0.05), while lactic acid, lactic acid/acetic acid, crude protein, starch, and the in vitro digestibility of dry matter and neutral detergent fiber increased (P < 0.05). Ammonia nitrogen/total nitrogen in the TMR silages with DW proportions of 0.75, 0.25 and 0 in the forage was more than 10%. These results indicated that the quality of the TMR silage containing DW alone as forage was poor, TMR silages containing DW proportions of 0.75 and 0.25, and ESC alone, in the forage were not well preserved. The optimum TMR silage formula contained a DW proportion of 0.5 in the forage.

Effects of maturity stage and lactic acid bacteria on the fermentation quality and aerobic stability of Siberian wildrye silage

It is difficult to make good quality of silage from alpine gramineous from the Qinghai Tibetan plateau. The effects of lactic acid bacteria (LAB) on the fermentation quality and aerobic stability of Siberian wildrye silage were studied in southeast of the Qinghai Tibetan plateau. Siberian wildrye materials were freshly cut at the sprouting stage, flowering stage, and milky stage. Silage was prepared by using a small‐scale silage fermentation system (bag silos). Lactobacillus plantarum (LP, 5 × 10⁸ cfu/kg FM), Lactobacillus buchneri (LB, 5 × 10⁸ cfu/kg FM) and their mixture (LP+LB, 5 × 10⁸ cfu/kg FM) as silage additives were separately added to ensiled forages, and no additive served as control (CK). These bag silos were kept at room temperature (<15°C), and the silage qualities were analyzed after 60 days of ensiling. The number of indigenous LAB on fresh materials was less than that of yeasts and molds, and LAB species showed specification adapted to low temperature. LAB inoculated silages had lower (P < 0.05) pH value, NH₃‐N/TN and butyric acid content compared with control silage. Silage treated with LB had higher contents of acetic acid, propionic acid, WSC and CP. However, the aerobic stability of silages inoculated with LAB did not differ significantly between stages (P > 0.05). When fermentation characteristics, chemical composition, and aerobic stability were considered, treatment with L. plantarum resulted in high quality of Siberian wildrye silage harvested at the flowering stage in the alpine region.

Changes in nutrient composition and in vitro ruminal fermentation of total mixed ration silage stored at different temperatures and periods

BACKGROUND

Total mixed ration (TMR) is widely used for dairy cattle and needs to be prepared daily because it deteriorates rapidly. Ensiling TMR allows preservation and saves labour at the farm; however, silage fermentation may influence various nutritional components. The objectives of this study were to evaluate nutritional changes and in vitro rumen fermentation of TMR silage that was stored at different temperatures and durations on a laboratory scale in comparison with those of typical TMR before ensiling.

RESULTS

No distinct changes in crude protein (CP), neutral detergent fibre and non-fibrous carbohydrate contents were observed during silage fermentation. However, clear changes were observed in the soluble CP and soluble sugar fractions; solubilisation of the CP fraction in TMR silage was enhanced by prolonged storage and higher storage temperatures, and most soluble sugars were lost during ensiling. Short-chain fatty acid concentrations in the in vitro rumen from TMRs before and after ensiling were not significantly different; however, throughout incubation, NH3 -N concentrations from TMR silages were significantly higher than those from TMR before ensiling.

CONCLUSION

A higher ruminal NH3 -N concentration from TMR silage may be a result of a shortage of fermentable sugars and enhanced deamination of CP. Feeding TMR ensiled under a high temperature must be investigated to balance proteins and carbohydrates for rumen fermentation.

Draft Genome Sequence of Lactobacillus panis DSM 6035T, First Isolated from Sourdough

We report a draft genome sequence of Lactobacillus panis DSM 6035^T, isolated from sourdough. The genome of this strain is 2,082,789 bp long, with 47.9% G+C content. A total of 2,047 protein-coding genes were predicted.

Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels

The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 10(7) to 10(10) cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 10(9) cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

Fermentation characteristics and lactic Acid bacteria succession of total mixed ration silages formulated with peach pomace

The objective of this study was to assess the use of peach pomace in total mixed ration (TMR) silages and clarify the differences in aerobic stability between TMR and TMR silages caused by lactic acid bacteria (LAB). The TMR were prepared using peach pomace, alfalfa hay or Leymus chinensis hay, maize meal, soybean meal, cotton meal, limestone, a vitamin-mineral supplement, and salt in a ratio of 6.0:34.0:44.4:7.0:5.0:2.5:1.0:0.1 on a dry matter (DM) basis. Fermentation quality, microbial composition, and the predominant LAB were examined during ensiling and aerobic deterioration. The results indicated that the TMR silages with peach pomace were well fermented, with low pH and high lactic acid concentrations. The aerobic stability of TMR silages were significantly higher than that of TMR. Compared with TMR silages with alfalfa hay, TMR silage with Leymus chinensis hay was much more prone to deterioration. Although the dominant LAB were not identical in TMR, the same dominant species, Lactobacillus buchneri and Pediococcus acidilactici, were found in both types of TMR silages after 56 d of ensiling, and they may play an important role in the aerobic stability of TMR silages.

Identification of bacteria in total mixed ration silage produced with and without crop silage as an ingredient

As a forage source for total mixed ration (TMR) silage production, locally produced crop silage is now used in addition to imported hay. This type of TMR ensiling is regarded as a two-step fermentation process; hence, a survey was carried out to determine whether the bacteria in crop silage affect the subsequent TMR ensiling. Fermentation product contents and bacterial community were determined for TMR silage and its ingredient silages collected in August, October and November. August product contained corn, sorghum and Italian ryegrass silages, October product had wheat silage exclusively and November product did not include any crop silages. Acetic acid, lactic acid, 2,3-butanediol and ethanol were predominant fermentation products in corn, sorghum, Italian ryegrass and wheat silages, respectively. Robust lactic acid fermentation was seen in TMR silage, even if acetate-type and alcohol-type silages were mixed as ingredients. The finding that bacterial community of the TMR silage appeared unrelated to those of ingredient silage supported this. Silages of various fermentation types can therefore be formulated without interfering with lactate-type fermentation in TMR silage.