Rumen Fermentation Characteristics Research Articles

Rumen microbiota helps Tibetan sheep obtain energy more efficiently to survive in the extreme environment of the Qinghai-Tibet Plateau.

T-sheep and H-sheep exhibit different environmental adaptability and production performance. The rumen microbiome has co-evolved with hosts and plays a vital role in nutrient digestion and energy metabolism. In our previous study, we found that T-sheep have a higher efficiency in energy metabolism than H-sheep, but the rumen microbial community remains unclear. In this study, we determined the rumen bacterial profile and rumen fermentation parameters to reveal the bacterial profiles and predictive functions among breeds and diets with four different energy levels, as well as the correlation between bacterial profiles and rumen fermentation characteristics. The results showed that the rumen total volatile fatty acids (VFAs), acetate, butyrate, total branched-chain VFAs, iso-butyrate, and iso-valerate were higher in T-sheep than H-sheep. The alpha diversity of ruminal bacteria is not affected by dietary energy, but it shows a distinction between the sheep breeds. Specifically, T-sheep rumen bacteria exhibit higher alpha diversity than H-sheep. The beta diversity of ruminal bacteria is not influenced by dietary energy or sheep breeds, indicating similar communities of ruminal bacteria between different diets and sheep breeds. The phyla of Bacteroidetes and Firmicutes predominate in the rumen, with a higher relative abundance of Firmicutes observed in T-sheep than H-sheep. The two most abundant genera in the rumen were Prevotella 1 and Rikenellaceae RC9 gut group. Prevotella 1 is the predominant bacterial genus in the rumen of H-sheep, while the Rikenellaceae RC9 gut group dominates in the rumen of T-sheep. Microbial co-occurrence network analysis reveals that variations in rumen fermentation characteristics result from differences in module abundance, with a higher abundance of VFA-producing modules observed in the rumen of T-sheep. Microbial function prediction analysis showed that dietary energy rarely alters the functional composition of rumen bacteria. However, there were differences in the functions of rumen bacteria between sheep breeds, with T-sheep showing a greater emphasis on energy metabolism-related functions, while H-sheep showed a greater emphasis on protein metabolism-related functions. These findings provide evidence of the special rumen microbial community that helps T-sheep efficiently obtain energy from low-protein and low-energy diets, enabling them to survive in the extreme environment of the Qinghai-Tibet Plateau.

Influence of dietary mulberry (Morus alba L.) leaf supplementation on production performance, blood metabolites, rumen fermentation characteristics and ruminal bacteria community in lactating dairy cows

The purpose of this study was to determine the effect of mulberry (Morus alba L.) leaf (ML) supplementation on the productivity, blood metabolism, rumen fermentation characteristics and rumen microbial population in lactating dairy cows. Twelve healthy multiparous Holstein dairy cows (initial characteristics: body weight = 442.83 ± 86.87 kg; milk yield = 12.55 ± 1.91 kg/d; days in milk = 150.0 ± 47.0 d) were randomly allocated to two treatment groups of six cows each. The cows were fed two different diets: a control diet (basal diet without ML; CTRL group) and a ML-supplemented diet (basal diet + 300 g ML; ML group). The trial lasted for a total of 28 d after an adjustment period of 14 d. The total rumen volatile fatty acid (VFA) levels (p = .063) and the propionate level (p < .05) were increased in the ML group, whereas the ratio of acetate to propionate was significantly decreased (p < .05). A microbiome study demonstrated that the dietary treatments significantly influenced the composition of rumen bacteria. The ruminal populations of Paludibacter propionicigenes, Ruminococcus sp. JE7A12 and Prevotella oris were greater (p < .05) in ML group than in CTRL group, while Enterococcus faecalis numbers significantly decreased (p < .05) in the ML group. Supplementing a dairy cow diet with 300 g ML has the potential to alter the microbial community and fermentation in the rumen, leading to an increase in propionate synthesis.

Metabolomic and morphologic surveillance reveals the impact of lactic acid-treated barley on in vitro ruminal fermentation.

Lactic acid (LA) treatment of cereals is known to improve ruminant performance. However, changes in cereal nutrient levels and variations in rumen fermentation remain unclear. This study was designed to compare the effects of 5% LA treatment on the trophic and morphological characteristics of barley and to discover the differences in rumen fermentation characteristics and metabolomes between LA-treated and untreated barley. Compared with those of untreated barley (BA), the dry matter (DM), crude protein (CP), ash and water-soluble carbohydrate contents of barley plants treated with 5% LA for 48 h (BALA) decreased, but the resistant starch (RS) and non-fiber carbohydrate contents increased. Moreover, the amount of proteinaceous matrix in BA decreased in response to LA treatment. During in vitro fermentation, BALA had a greater pH but lower dry matter disappearance and ammonia, methane, and short-chain fatty acid levels than BA. The differential metabolites between BA and BALA were clustered into metabolic pathways such as purine metabolism, lysine degradation, and linoleic acid metabolism. Observable differences in ultrastructure between BALA and BA were noted during fermentation. Lactic treatment altered barley nutrient content, including DM, CP, RS, ash, water-soluble carbohydrates and non-fiber carbohydrates, and affected barley ultrastructure. These variations led to significant and incubation time-dependent changes in the in vitro fermentation characteristics and metabolome.

The effect of supplementation with rubber seed kernel pellet on in vitro rumen fermentation characteristics and fatty acid profiles in swamp buffalo

BackgroundRubber seed kernel is a by-product derived from rubber tree plantations. It is rich in C18 unsaturated fatty acids (UFA) and has the potential to be used as a protein source for ruminant diets. This investigation has been conducted to determine the influence of rubber seed kernel pellet (RUSKEP) supplementation on in vitro rumen fermentation characteristics and fatty acid profiles in swamp buffalo. Using a completely randomized design (CRD) and supplementation of RUSKEP at 0, 2, 4, 6, 8, and 10% dry matter (DM) of substrate.ResultsThe supplementation with RUSKEP had no effect on gas kinetics, cumulative gas production, or degradability. Ruminal pH decreased linearly (P < 0.01) and ammonia-nitrogen (NH3-N) concentration decreased quadratically (P < 0.01) by RUSKEP supplementation. The proportion of acetate (C2) decreased linearly (P < 0.01), but propionate (C3) and butyrate (C4) increased linearly (P < 0.01), resulting in a decrease in the acetate to propionate ratio (C2:C3) (P < 0.01) by RUSKEP supplementation. With an increasing level of dietary RUSKEP, there was a slight increase in UFA in the rumen by increasing the oleic acid (OA; C18:1 cis-9 + trans-9), linoleic acid (LA; C18:2 cis-9,12 + trans-9,12), and α-linolenic acid (ALA; C18:3 cis-9,12,15) concentrations (P < 0.01).ConclusionsAdding up to 10% of RUSKEP could improve in vitro rumen fermentation and C18 unsaturated fatty acids, especially ALA, in swamp buffalo.

Effects of dietary protected fat and vitamin E on in vitro rumen fermentation characteristics and reproductive performances of Hanwoo cows

Effects of dietary protected fat and vitamin E on in vitro rumen fermentation characteristics and reproductive performances of Hanwoo cows

Ficus hookeri tree leaves as herbal feed additives to enhance ruminal fermentation and reduced protozoal population in growing crossbred cattle

An experiment was conducted to evaluate the effect of dietary supplementation of Ficus hookeri leaf meal as herbal feed additive on rumen protozoal population, enzyme profile and fermentation characteristics in growing crossbred calves. Ten growing male crossbred (Jersey × Tharparker) calves with similar initial body weight of 91.8+1.37 kg, were randomly divided into two equal groups (T1 and T2) and fed individually under stall feeding for 140 days on a mixed ration containing rice straw and concentrate mixture in 50:50 ratio. Two types (C1 and C2) of iso-nitrogenous concentrate mixtures were prepared. Wheat bran in concentrate mixture (C2) of test group (T2) was partially replaced (4 parts w/w) with Ficus hookeri leaf meal. Daily dry matter intake between two experimental groups was similar. Rumen pH, NH3-N concentration and total rumen protozoal population decreased while ruminal TVFA and propionic acid production increased due to dietary supplementation of Ficus hookeri leaf meal as herbal feed additive. Activity of carboxymethyl cellulase, xylanase and b-glucosidase enzymes were significantly higher in the rumen liquor of calves fed Ficus hookeri leaf meal. It could be concluded that dietary supplementation of Ficus hookeri leaf meals as herbal feed additive have a potential for reducing rumen protozoal population and ammonia nitrogen concentration with improving ruminal TVFA and propionate production in growing crossbred calves.

Influence of BOVAMINE DEFEND Plus on growth performance, carcass characteristics, estimated dry matter digestibility, rumen fermentation characteristics, and immune function in finishing beef steers.

One hundred and eighty crossbred beef steers (406.0 ± 2.2kg) were used to determine the impact of a novel direct-fed microbial (DFM) on growth performance, carcass characteristics, rumen fermentation characteristics, and immune response in finishing beef cattle. Steers were blocked by body weight (BW) and randomly assigned, within block, to 1 of 2 treatments (3 replicates/treatment: 30 steers/replicate). Treatments included: (1) no DFM (control) and (2) DFM supplementation at 50 mg ∙ animal-1 ∙ d-1 (BOVAMINE DEFEND Plus). All steers were fed a high-concentrate finishing diet and individual feed intake was recorded daily via the GrowSafe system. BWs were collected every 28 d. On day 55, 10 steers per pen were injected with ovalbumin (OVA). Jugular blood samples were collected from each steer on days 0, 7, 14, and 21 post injection. On day 112, the same steers were injected again with OVA and intramuscularly with a pig red blood cell solution. Jugular blood samples were collected from each steer on days 0, 7, 14, and 21 post injection. On day 124, rumen fluid was collected from 3 steers per treatment and used to estimate in vitro rumen fermentation characteristics. Equal numbers of steers per treatment were transported to a commercial abattoir on days 145, 167, and 185 of the experiment, harvested, and carcass data were collected. Initial BW was similar across treatments. On days 28 and 55, steers receiving DFM had heavier BW (P < 0.01) compared to controls. The average daily gain was greater in DFM-supplemented steers from days 0 to 28 (P < 0.01) and days 0 to 55 (P < 0.01) of the experiment compared to controls. Overall dry matter intake (DMI) was greater (P < 0.04) and overall feed efficiency was similar in DFM-supplemented steers compared to controls. Dressing percentage (P < 0.02) was greater in steers receiving DFM compared to controls. Antibody titers to injected antigens were similar across treatments. However, red blood cell superoxide dismutase activity was greater (P < 0.05) in DFM-supplemented steers compared to controls. In vitro molar proportions of isobutyric and butyric acid were greater (P < 0.01) and dry matter (DM) digestibility tended (P < 0.07) to be greater in rumen fluid obtained from steers supplemented with DFM. These data suggest that BOVAMINE DEFEND Plus supplementation improves growth performance during the initial period of the finishing phase, increases overall DMI and dressing percentage, and may impact antioxidant status in beef cattle.

Nutrient digestibility, characteristics of rumen fermentation, and microbial protein synthesis from Pesisir cattle diet containing non-fiber carbohydrate to rumen degradable protein ratio and sulfur supplement.

To achieve optimal feed efficiency in ruminants, especially Pesisir cattle, it is necessary to maintain a harmonious equilibrium between energy and protein levels within the rumen. Sulfur supplementation can potentially escalate the energy-protein balance in the rumen. The aim of this study was to explore the formulation of ruminant diets by synchronizing rumen degradable protein (RDP) and non-fiber carbohydrate (NFC) while adding sulfur minerals at different levels. Nutrient digestibility, NH3 concentration, volatile fatty acids (VFA) production, microbial protein synthesis (MPS), and methane gas production were assessed. We employed a randomized block design with a 2 × 2 × 3 factorial arrangement and examined diverse incubation periods of 6, 24, and 48 h. Treatment consisted of RDP (60% and 65%), NFC (35% and 40%), and sulfur (0%, 0.15%, and 0.3%) levels. In this study, the Tilley and Terry in vitro technique, which used Pesisir cattle's rumen fluid, was employed to assess the digestibility of dry matter, organic matter, acid detergent fiber, neutral detergent fiber, and RDP-Rumen undegradable protein. In addition, it measures various rumen fluid attributes, including pH, NH3, VFA, MPS, and methane gas production. Treatment with a coordinated combination of 65% RDP and 40% NFC combined with 0.15% sulfur supplement yielded significantly improved digestibility and notably reduced methane gas production (p < 0.05). The enhancement in digestibility and reduction in methane gas emissions can be attributed to the interaction of RDP, NFC, and sulfur. Feed digestibility was increased in the 65% RDP treatment with 40% NFC and 0.15% sulfur, along with a decrease in methane gas production.

Effects of Isochlorogenic Acid on Ewes Rumen Fermentation, Microbial Diversity and Ewes Immunity of Different Physiological Stages.

The effects of isochlorogenic acid (ICGA) on ewes rumen environment, microbial diversity, and immunity at different physiological stages (estrus, pregnancy and lactation) were studied in this experiment. Twenty healthy female Hu lambs of 1.5 months with similar body weight (17.82 ± 0.98 kg) and body condition were selected and randomly divided into two groups: the control group (CON) and the ICGA group (ICGA). The lambs of CON were fed a basal diet, while the lambs of ICGA were supplemented with 0.1% ICGA based on the basal diet. Lambs rumen fermentation characteristics, microbial diversity and immunity at estrus, pregnancy, and lactation stages were determined and analyzed, respectively. The results showed that the rumen pH in CON increased first and then decreased as lambs grew (p < 0.05). However, it showed the opposite change in ICGA. The content of ammonia nitrogen (NH3-N) showed the highest at estrus stage in both groups, but it was significantly higher in ICGA than that in CON (p < 0.05). The Acetic acid/propionic acid (A/P) ratio at estrus stage and the volatile fatty acids (VFAs) at pregnancy stage in ICGA were significantly higher than those of the CON (p < 0.05). The 16S rDNA sequencing analysis showed that the Shannon, Chao 1 and ACE indexes of the ICGA were significantly higher than those of the CON both at estrus and lactation stages (p < 0.05), while they showed higher at the pregnancy stage in CON (p > 0.05). Principal component analysis (PCA) showed that there were significant differences in rumen microorganism structure between CON and ICGA at all physiological stages (p < 0.01). At the phylum level, compared with the CON, Firmicutes relative abundance of three physiological stages decreased (p > 0.05) while Bacteroidota increased (p > 0.05). The relative abundance of Synergistota at estrus stage and Patescibacteria at the lactation stage increased significantly too (p < 0.05). At the genus level, compared with the CON, the relative abundance of Prevotella at three stages showed the highest (p > 0.05), while the relative abundance of Succiniclasticum, unclassified_Selenomonadaceae and Rikenellaceae_RC9_gut_group showed different abundances at different physiological stages in ICGA. Compared with the CON, the lambs of the ICGA showed higher blood IgG, IgM, and TNF- α contents at three physiological stages and higher IL-6 contents at pregnancy stage (p < 0.05). Conclusion: Adding ICGA could regulate ewes rumen fermentation mode at different physiological stages by increasing rumen NH3-N at estrus, VFAs at pregnancy, and the ratio of A/P at lactation. It optimizes rumen microbial flora of different physiological stages by increasing Bacteroidota relative abundance while reducing Firmicutes relative abundance, maintaining rumen microbial homeostasis at pregnant stage, increasing the number of beneficial bacteria in later lactating and ewes blood immunoglobulins content at three physiological stages.

Estimation of ruminal digestibility and fermentation characteristics of coffee pulp: A meta-analysis of in vitro experiments

Integrating various studies with statistical methods can be used by applying a meta-analysis method. The objective of this meta-analysis was to evaluate the effect of coffee pulp as ruminant feed on in vitro digestibility and rumen fermentation characteristics. The database was developed from six related articles containing 25 studies, collected from Scopus and Google Scholar. The parameters integrated were in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD), pH value, total volatile fatty acids (VFA), NH3 and total protozoa. The data were analyzed using a mixed model methodology. The level of coffee pulp was considered as a fixed factor and the different studies as a random effect. The results revealed that coffee pulp addition had a significant quadratic effect to enhance IVDMD (P<0.01) and a significant linear effect to decrease total VFA (P<0.05). However, coffee pulp addition did not significantly affect (P>0.05) on IVOMD, pH, NH3 and total protozoa. In conclusion, coffee pulp can be used as an alternative feedstuff due to its good digestibility in the rumen. Nevertheless, it should be applied in the right amount to avoid negative effects on animal performance.

Use of irradiated chitosan as a matrix for slow-release urea and in vitro fermentation characteristics of slow-release urea supplementation in ruminant rations

Background and Aim: Irradiated chitosan can be used as a matrix for slow-release urea (SRU) production. This study aimed to (1) determine the optimal formulation of irradiated chitosan matrix for controlling nitrogen release and (2) evaluate the characteristics of SRU in vitro fermentation based on irradiated chitosan as a feed supplement. Materials and Methods: In the first phase of the investigation, four chitosan-based SRU formulations with varying amounts of acrylamide (3 and 5 g) and gamma irradiation (5 and 10 kGy) were evaluated. Scanning electron microscopy, Fourier transform mid-infrared spectroscopy, and ammonia release characteristics were used to observe morphological, functional group, and ammonia release characteristics. In the second phase of research, the most effective SRU formulation was utilized as a supplement to ruminant rations based on rice straw, sorghum straw, and alfalfa. Gas production, rumen fermentation characteristics, and methane gas production were observed in vitro. Results: On the basis of surface image analysis, the four SRU formulas generate a similar appearance. Compared with untreated urea, the SRU3 formula reduced the percentage of ammonia emission by 12.85%–27.64% after 24 h of incubation (p = 0.05), as determined by the first phase study. SRU3 became the basis for the second testing phase. The addition of SRU3 did not affect the optimal gas production in vitro. SRU3 treatment produced less gas than Optigen® treatment (p = 0.05). With regard to rumen fermentation and digestibility, Optigen® yielded better results than SRU3 (p = 0.05). However, the treatment with SRU3 resulted in reduced methane production compared to that in the control (p = 0.05). Conclusion: Irradiated chitosan as an SRU matrix may control the release of ammonia in the rumen medium. The SRU3 formulation is the most effective. The addition of SRU to rice straw-based rations reduces methane production without affecting in vitro digestibility. Keywords: fermentation characteristics, irradiated chitosan, ruminant, slow-release urea.

Effects of fibrolytic enzyme supplementation on feed intake, digestibility and rumen fermentation characteristics in goats fed with Leucaena silage

The primary objective of this study was to determine the effect of adding fibrolytic enzyme cocktail, which was derived from dried tomato pomace treated with Aspergillus niger, to Leucaena silage on total gas production by using in vitro gas techniques. In addition, the effect of these enzymes on voluntary feed intake, nutrient digestibility, and rumen fermentation were determined using 8 male, crossbred Anglo Nubian x Native goats. The experiment was designed as a replicated 4 × 4 Latin square. The experimental treatments were randomly assigned to each sequence of feeding of the 4 experimental treatments, i.e., 0%, 0.2%, 0.4%, and 0.8% (dry matter) of enzyme cocktail supplemented to Leucaena silage. The addition of 0.4% enzyme cocktail increased total gas production at 96 h, which was not different from the addition of commercial cellulase. Gas production from the insoluble fraction (b) was improved by increasing the enzyme cocktail levels (P = 0.039). The voluntary intake of Leucaena silage increased with an increase in the addition of enzyme level (P = 0.025). The dry matter, organic matter, crude protein, NDF and ADF digestibility’s were also increased by increasing the addition of enzyme cocktail level. The addition of enzyme cocktail increased the Prevotella_1 in rumen fluid compared with the untreated group. In conclusion, at 0.4%, the fibrolytic enzyme cocktail derived from A. niger increased feed intake, nutrient digestibility, and ruminal fibrolytic bacteria community in goats.

Condensed tannin-induced variations in the rumen metabolome and the correlation with fermentation characteristics in goats.

In this study, we characterized the effects of CT dietary inclusion at 2% (wt/wt) dry matter on the goat rumen metabolome and fermentation characteristics. Barley (BA) and corn (CN) were separately used as basal grain for the control rations, and rations supplemented with CT were BACT and CNCT, respectively. The rations were tested using eight Japanese Shiba × Saanen goats in a replicated 4 × 4 Latin square arrangement (28 days for each period). Ruminal fluid was obtained on day 25 of each period, and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) analysis was performed. Metabolites from BACT against BA and CNCT against CN were mostly associated with purine metabolism. Moreover, BACT against BA showed intensified biosynthesis of unsaturated fatty acids, and CNCT against CN resulted in strengthened amino acid metabolism. Furthermore, strong correlations were observed between rumen NH3 -N and the copy number of total bacteria with most of the differential metabolites. The present paper provides a better understanding of the relationship between the rumen metabolome and fermentation characteristics and supports a shift in concern about using CT as a strategy to manipulate rumen metabolism.

The Use of R Programming Language for Modelling In vitro Rumen Fermentation Gas Production

The in vitro gas production technique is one of the feed evaluation methods that capture the characteristics of rumen microbial fermentation in response to the gas produced by feed ingredients. The gas production response is related and modelled to a unit of time with several parameters using non-linear regression mathematical equations. To facilitate this task, a script program in R has been developed that can perform the intended calculations. The calculation process uses nonlinear mathematical equations with intercepts. The equation shows that gas production (P) (mL) is influenced by several constants that indicate the share of gas production from the soluble fraction (FA) (mL), gas production from the potentially soluble part (FB) (mL), gas production rate (KC) (mL/h) and incubation time (T) (h). In addition to P and T, the three constants are tried to be derived by the program created. The data set is taken from several in vitro gas production studies that have been conducted previously. The Neway Software program of curve fitting calculations was used to validate the results, as the mean difference was tested using an unpaired T-test. Both programs showed the same calculation results for FA (P=0.9996), FB (P=0.9998), and KC (P=0.9962). The residual standard error (RSE) and R-square (R2) values of both programs also came with the same result they were RSE (P =0.9978), and R2 (P=0.6087) respectively. This shows that the R program script made can carry out the calculation process of making a model of the gas production equation for modeling in vitro gas production from rumen fermentation.

Chemical composition and in vitro rumen fermentation characteristics of various tropical seaweeds.

This research aimed to evaluate potential tropical seaweed from Indonesia as an ingredient or supplement feed for ruminants based on chemical composition and in vitro rumen fermentation parameters. The seven natural tropical seaweeds (three green and four red species) were collected from Ndrini and Sepanjang Beach, Gunungkidul, Yogyakarta, Indonesia. The experimental design on secondary metabolite profiles used a completely randomized design, and the in vitro gas production test used a randomized complete block design with seven seaweed species variances and four replications (blocks) based on rumen fluid collection time. The data obtained was analyzed using analysis of variance (ANOVA), and Duncan's Multiple Range Test was used to test the variation in the analysis. The seven tropical seaweed species have potential as mineral sources for ruminants, except for macromineral (P and S) and micromineral (Cu). The red tropical seaweed has potential as a protein source (Gelidium spinosum (S.G.Gmelin) P.C. Silva, Hypnea pannosa, and Acanthopora muscoides (L.) Bory), and the green seaweed (Chaetomorpha linum (O.F. Mull.) Kutz and Cladopora sp.) has potential as a crude fiber (CF) source for ruminants. As indicated by secondary metabolites and gas production in vitro, the green species (C. linum (O.F. Mull.) Kutz and Enteromorpha compressa) and red species (A. muscoides (L.) Bory and Gelidium amansii (J.V. Lamouroux) J.V. Lamouroux) could be degraded in the rumen and had quite high phenolic compounds. The seven tropical seaweed species have the potential to be an ingredient or supplement feed for ruminants, and there were four species that have the potential to reduce methane emissions.

A Study on Rumen Fermentation Characteristics and Greenhouse Gas Emission of Forages in South Korea

A Study on Rumen Fermentation Characteristics and Greenhouse Gas Emission of Forages in South Korea

In vitro assessment of ruminal biohydrogenation of polyunsaturated fatty acids in diets with different types and levels of protected fat and diverse sources of fibre.

The objective was to assess the in vitro rumen fermentation characteristics, methane production, and biohydrogenation of unsaturated fatty acids of diets with two protected fat (PF) sources from soybean or linseed oil, two levels of PF (0 and 6%) and two forage sources (canola silage (CS) or alfalfa hay (AH)) in a factorial 2x2x2 completely randomised design. Only fatty acids content at final incubation was affected (P<0.05) by triple interaction, where C18:2 was highest with AH plus 6% soybean PF (4.41mg/g DM), while C18:3 was with CS plus 6% linseed oil protected (1.98mg/g DM). C18:2 cis-9 trans-11 had high concentration (308 mg/g DM; P<0.05) with AH plus 6% PF regardless PF type, and C18:1 trans-11 was higher with 6% PF than without PF (13.41 vs 7.89 mg/g DM). Cumulative methane production was not affected by treatments (0.9973 ± 0.1549 mmol/g DM; P>0.05). Gas production and in vitro NDF digestibility were lower with 6% PF of linseed than soybean (160.88 vs 150.97 ml; and 69.28vs 62.89 %, respectively P<0.05). With linseed PF the NH3-N concentration was highest in CS than AH (41.27 vs 27.95 mg/dL; P<0.05) but IVDMD had the opposite result (78.54 vs 85.04). In conclusion, although methane production was not affected and in vitro digestibility and gas production were reduced with linseed PF, the concentration of C18:3 and C18:1 trans-11 was increased, which could improve the lipid profile of milk. The negative effects on digestibility were less with AH than of CS regardless of PF type and level.

The Influence of Tannins, Saponins, and Direct Fed Microbials on In Vitro Rumen Fermentation Characteristics and Microbiota

In-vitro experiments were conducted to determine the impact of tannins, saponins, and DirectFed-Microbials (DFM) on rumen fermentation characteristics. Rumen fluid was collected 2h post feeding from three cannulated crossbred (Angus x Hereford) feedlot steers (450±12.2 kg), adjusted to finishing diet. Rumen fluid from all steers were filtered, combined, and mixed with buffer. Vaccine bottles containing ground finishing diet and appropriate treatments were incubated with rumen fluid mixture (39 ˚C). Treatments consisted of 1) Control; 2) Commercial Tannin (TCH); 3) Hydrolysable Tannin (HT); 4) saponin; 5) TCH+DFM; 6) HT+DFM; and 7) Saponin+DFM. At 12 h post incubation, HT+DFM and Saponin+DFM had lesser (P&lt;0.05) molar proportions of acetic acid when compared to all other treatments. Saponin+DFM had greater (P&lt;0.05) molar proportions of propionic acid and a lesser (P&lt;0.05) acetate: propionate ratio when compared to treatments not containing DFM. Dry matter digestibility and pH were greater (P&lt;0.05) for saponin, TCH+DFM, HT+DFM and saponin+DFM, whereas pH was greater in treatments containing DFM compared to the controls. Percent CO2 was lesser (P&lt;0.05) in saponin and THC+DFM in vitro vessels compared to controls. At 18 h post fermentation total VFA concentrations, molar proportions of butyric and valeric acid, and gas cap N2 percentage were greater (P&lt;0.05) in in vitro vessels containing HT+DFM compared to controls. The percentage of CO2 was lesser in in vitro vessels containing HT compared to control and in vitro vessels containing saponin, HT+DFM and Saponin+DFM. At 12 h, alpha and beta diversity of the microbial community between treatments differed (P&lt;0.05). Across all samplesat 18 h of fermentation the genera Sharpea and Dialister were present, however Saponin+DFM and TCH+DFM treatments demonstrated the greatest relative abundance. While Sharpea contribute to rumen biohydrogenation, the presence of genus Dialister indicates association with energy harvesting bacteria and suggests that the inclusion of several of these feed additives allowed shifts of certain bacteria to occur.

Combined effects of nitrate and medium-chain fatty acids on methane production, rumen fermentation, and rumen bacterial populations in vitro

This study investigated the combined effects of nitrate (NT) and medium-chain fatty acids (MCFA), including C8, C10, C12, and C14, on methane (CH4) production, rumen fermentation characteristics, and rumen bacteria using a 24 h batch incubation technique. Four types of treatments were used: control (no nitrate, no MCFA), NT (nitrate at 3.65 mM), NT + MCFA (nitrate at 3.65 mM + one of the four MCFA at 500 mg/L), and NT + MCFA/MCFA (nitrate at 3.65 mM + a binary combination of MCFA at 250 and 250 mg/L). All treatments decreased (P < 0.001) methanogenesis (mL/g dry matter incubated) compared with the control, but their efficiency was dependent on the MCFA type. The most efficient CH4 inhibitor was the NT + C10 treatment (− 40%). The combinations containing C10 and C12 had the greatest effect on bacterial alpha and beta diversity and relative microbial abundance (P < 0.001). Next-generation sequencing showed that the family Succinivibrionaceae was favored in treatments with the greatest CH4 inhibition at the expense of Prevotella and Ruminococcaceae. Furthermore, the relative abundance of Archaea decreased (P < 0.05) in the NT + C10 and NT + C10/C12 treatments. These results confirm that the combination of NT with MCFA (C10 and C12 in particular) may effectively reduce CH4 production.

Effect of Adding Fermented Juice of Epiphytic Lactic Acid Bacteria Prepared with Different Sources of Soluble Carbohydrates on Fermentation Characteristics of Wheat Straw Silage, Rumen Fermentation and Nutrients Digestibility by Awassi Lambs

This study was conducted to determine the effect of using different sources of water soluble carbohydrates (WSC) in preparation of fermented juice of epiphytic lactic acid bacteria (FJLB) added at ensiling on fermentation characteristics of wheat straw silages (WSS), rumen fermentation and nutrients digestibility by Awassi lambs. The FJLBs were prepared from wild reed plant with glucose at 2% (w/v, FJLB-G), cane molasses at 5% (w/v, FJLB-M) or date molasses at 5% (w/v, FJLB-D). Wheat straw were ensiled for 45 days with addition of FJLBs at level of 1%, for control WSS, distilled water was added at similar quantity as FJLB (WWS-C). Urea and molasses were added to all WSS at level of 1 and 10% on dry matter (DM) basis. Twelve lambs were used in 4 treatments with 3 lambs per each. Lambs were fed concentrate diet at 3% of their BW with free allowances of WSS. Results revealed that ensiling WS with FJLBs improved silage fermentation as evidenced by lower (P<0.01) pH and ammonia nitrogen (NH3-N) concentration together with higher (P<0.01) lactic acid (LA) and volatile fatty acids (VFA) concentrations. Higher (P<0.01) digestibilities of most nutrients including cell wall components were associated with lambs fed WSS-M and WSS-D as compared with those fed WSS-G and WSS-C. However, higher (P<0.01) organic matter (OM) and crude protein (CP), digestibilities were recorded by lambs fed WSS-M. Moreover, ruminal NH3-N and VFA were positively influenced by feeding WSS prepared with FJLB in general, FJLB-M and FJLB-D in particular.