Biohydrogenation Of Fatty Acids Research Articles

Effect of rumen-protected fat on in vitro rumen fermentation and apparent biohydrogenation of fatty acids

Effect of rumen-protected fat on in vitro rumen fermentation and apparent biohydrogenation of fatty acids

Role of whole linseed and sunflower seed on the nutritional and organoleptic properties of Podolian × Limousine meat

The fatty acids profile of meat can be influenced by the amount and type of the lipid supplemented in animal feeding with a modulation of the rumen biohydrogenation of dietary polyunsaturated fatty acids (P UFA). Therefore, the aim of the present study was to assess the nutritional and sensory quality of bovine meat as affected by different oilseeds supplementations. Thirty two Podolian x Limousine young bulls were randomly allocated into four experimental treatments: control diet (CO) with no supplemental fat, linseed diet (LS) with a supplementation of 10% whole linseed; sunflower diet (SS) with supplementation of 10% of sunflower seeds; LS+SS diet: with supplementation of linseeds (5%) and sunflowers (5%). After finishing period (140 days), all animals were slaughtered and fatty acids profile and sensory proprieties were evaluated on meat. The results showed that dietary supplementation with linseed or/and sunflower seeds in the diet decreased the percentage of saturated fatty acids (P<0.001) and increased monounsatured (P<0.05) and polyunsaturated fatty acids (P<0.05). Feeding diets containing linseeds as respect with sunflower seeds increased the amount of total n-3 P UFA (P<0.01) and, in particular, of linolenic (P<0.01), eicosapentaenoic (P<0.001), docosapentaenoic (P<0.01) and docosaeasoenoic (P<0.05) acids. An improvement in tenderness, juiciness, chewiness and flavour intensity was observed in beef from animals supplemented with oilseeds. This study suggests that linseed alone or in combination with sunflower seeds is an effective strategy to enrich meat with beneficial fatty acids and to improve some sensory attributes appreciated by consumers.

Milk Odd- and Branched-Chain Fatty Acids as Biomarkers of Rumen Fermentation.

Cow's milk and dairy products are the primary sources of OBCFAs, which have beneficial health properties. The goal of this study was to identify the factors that influence the content of OBCFAs in cow's milk and to indicate which OBCFAs can serve as biomarkers for fermentation processes. The content of OBCFAs in milk depends on the species of ruminants, with studies showing that this varies between 3.33% (in goat's milk) and 5.02% (in buffalo's milk). These differences also stem from the animals' energy balance, lactation phases, forage-to-concentrate ratio, and the presence of bioactive compounds in feeds, as well as management practices and environmental conditions. The OBCFAs in milk fat mainly come from rumen bacteria, but can also be synthesized de novo in the mammary gland, making them potentially useful noninvasive indicators of rumen fermentation. The concentration of BCFA is lower in colostrum and transitional milk than in full lactation milk. The proportions of total OBCFAs are higher in first- and second-parity cows. The most effective predictors of the biohydrogenation of fatty acids in the rumen are likely C18:2 cis-9, trans-11, iso-C16:0, and iso-C13:0. OBCFAs have been identified as potential biomarkers for rumen function, because their synthesis depends on specific bacteria. Strong predictors of subclinical ruminal acidosis include iso-C14:0, iso-C13:0, and C15:0. The concentration of ∑ OBCFA >C16 in milk is associated with fat mobilization and serves as a significant marker of the energy balance in cows.

Fatty Acid Biohydrogenation, Fermentation, and Digestibility of Ration Containing Napier and King Grass with Different Harvest Ages and Altitudes: In Vitro Study

Fatty Acid Biohydrogenation, Fermentation, and Digestibility of Ration Containing Napier and King Grass with Different Harvest Ages and Altitudes: In Vitro Study

In vitro Study of Neem Bark Extract on Rumen Fermentation and Biohydrogenation of Polyunsaturated Fatty Acids

In vitro Study of Neem Bark Extract on Rumen Fermentation and Biohydrogenation of Polyunsaturated Fatty Acids

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.

Determining Optimal Nonlinear Regression Models for Studying the Kinetics of Fatty Acid Ruminal Biohydrogenation In Vitro.

The accurate estimation of in vitro ruminal biohydrogenation (BH) kinetics of fatty acids (FA) allows for a more accurate understanding of their dynamics and develop targeted strategies to enhance desirable FA bypass. This study comprises a comprehensive evaluation of 33 nonlinear regression models to determine the most suitable model for accurately estimating the in vitro BH kinetics of individual FA. The data set utilized in the present research originates from a recent investigation on the effects of micronization and vitamin E on the in vitro ruminal BH of rapeseed. For the nonlinear regression analysis, data comprising FA concentrations (expressed as g FA/100 g FA) at the conclusion of 2, 4, 8, 12, 24, and 48 h incubation periods were employed. The evaluation of nonlinear regression models focused on identifying the ideal model based on criteria including the highest R2 value, the lowest RMSE value, and statistically significant coefficients. The results pinpoint the Gompertz model as an effective choice for estimating the in vitro ruminal BH kinetics of upward-trending fatty acids, including intermediate unsaturated fatty acids and saturated end FA. Additionally, the first-order kinetic model of Ørskov and McDonald emerges as the preferred model for investigating the BH kinetics of downward-trending fatty acids, including oleic acid, linoleic acid, and alpha-linolenic acid. In summary, this rigorous evaluation led to the identification of the most appropriate model, one that not only exhibited an exceptional fit to the data but also provided profound insights into the intricate relationships between predictors and the dynamic behavior of FA. The established nonlinear regression models will serve as invaluable tools for future research investigating FA biohydrogenation kinetics.

Effects of sunflower oil infusions of Asparagopsis taxiformis on in vitro ruminal methane production and biohydrogenation of polyunsaturated fatty acids

Asparagopsis taxiformis inhibits ruminal methane (CH4) production due to its bromoform (CHBr3) content. The immersion of A. taxiformis in edible vegetable oils allows the extraction and stabilization of the highly volatile CHBr3 in the oil phase. The objectives of this study were to explore the effects of adding sunflower oils with increasing concentrations of CHBr3 on in vitro ruminal methanogenesis and biohydrogenation. Five batches of 48-h in vitro incubations were performed in 14 fermentation bottles, using rumen inocula collected shortly after the slaughter of young crossbred bulls and 1 g of dry matter (DM) from a total diet of mixed feed without added oil (control) or with 60 μL of sunflower oil per gram of DM as the substrate. The treatments were the CHBr3 content in the oil added: 0 μg (B0), 25 μg (B25), 50 μg (B50), 75 μg (B75), 100 μg (B100), and 150 μg (B150) of CHBr3 per gram of substrate DM. Organic matter (OM) degradability, total gas, CH4, volatile fatty acids (VFA), long-chain fatty acids, and dimethyl acetals (DMA) were analyzed at the end of each incubation. Data were analyzed with a model considering the treatments as the fixed effect and the run as a random block and using orthogonal contrasts. Degradability of OM was higher in the control group and was unaffected by CHBr3 concentration. Total gas production per gram of degraded OM was unaffected by treatments and averaged 205 ± 29.8 mL/g. Methane (mL) production decreased linearly with increasing CHBr3 concentrations, with 33%, 47%, and 87% reductions for B75, B100, and B150, respectively. Total VFA concentration was unaffected by oil inclusion but was reduced by 20% in CHBr3-containing treatments, although without any dose-response pattern. The molar percentage of acetate decreased linearly, whereas propionate and butyrate increased linearly with the increasing CHBr3 dosage. Including oil in the diet decreased the branched-chain fatty acids and DMA content. Increasing CHBr3 concentrations did not affect branched-chain fatty acids, but linearly increased most of the identified DMA. Adding oil to the control diet increased the 18:2n-6, whereas increasing the concentration of CHBr3 had no effect on 18:2n-6 but decreased linearly the 18:0 and increased the trans-18:1 isomers. The results obtained provide evidence that oil immersions of A. taxiformis can successfully inhibit ruminal production of CH4 in vitro at doses of 100 and 150 μg/g DM, and simultaneously modulate biohydrogenation.

The Dose-Dependent Role of Sage, Clove, and Pine Essential Oils in Modulating Ruminal Fermentation and Biohydrogenation of Polyunsaturated Fatty Acids: A Promising Strategy to Reduce Methane Emissions and Enhance the Nutritional Profile of Ruminant Products

The livestock industry significantly contributes to greenhouse gas emissions, with ruminant animals, including cows, sheep, and goats, being responsible for a substantial share of these emissions due to methane production. Reducing methane emissions from ruminants is crucial for mitigating the environmental impact of livestock production. Additionally, there has been a growing interest in improving the nutritional quality of ruminant products through modifying their profile of fatty acids. The current study aimed to investigate the potential of sage (SAG), pine (PIN), and clove (CLO) essential oils as natural additives for modulating in vitro ruminal fermentation characteristics and biohydrogenation of polyunsaturated fatty acids (PUFA). Within the current experiment, three dose levels (300, 600, and 900 mg/L) of essential oils were evaluated using rumen inoculum from three mature Dalagh ewes (58 ± 2.84 kg body weight). The results revealed that the essential oils had a significant impact on gas production, methane and carbon dioxide production, ruminal fermentation parameters, and ruminal biohydrogenation of dietary PUFAs. The essential oil treatments resulted in reduced gas production compared with the control group. Methane production was significantly reduced by all doses of the essential oils, with the highest dose of CLO resulting in the lowest methane production. In addition, the essential oils affected ruminal fermentation parameters, including pH, ammonia concentration, and production of total volatile fatty acids. Promising modifications in ruminal biohydrogenation of PUFAs and the profile of fatty acids were also observed in the current study. These findings suggest that SAG, Pin, and CLO hold promise in mitigating methane emissions and improve the nutritional value of ruminant products. Further investigation is required to evaluate their effectiveness in practical feeding strategies for livestock.

Effect of Feeding Dried Apple Pomace on Ruminal Fermentation, Methane Emission, and Biohydrogenation of Unsaturated Fatty Acids in Dairy Cows

Industrial fruit by-products are now being utilized as animal feeds for several reasons. They may substitute the conventional cereal feeds, and also offer economic and environmental benefits. One of the most important industrial fruit by-products is apple pomace, which can be used as a source of energy in the ration of ruminant species, including dairy cattle. The aim of the present study was to evaluate the effect of feeding dried apple pomace to dairy cattle on ruminal fermentation, fatty acid concentration, microbial populations, and methane production. The experiment lasted 64 days and was conducted with 4 cannulated commercial dairy cows. The control animals received a standard diet, while the experimental animals was fed a standard diet supplemented with 150 g/kg DM dried apple pomace. Ruminal fluid samples were collected at three different time intervals. The samples were obtained at 0-, 3-, and 6-h post-feeding. The ruminal fluid was used to assess the ammonia concentration, pH, volatile fatty acids (VFA), long-chain fatty acids (FA), microbial population. A number of ruminal fermentation variables changed as a result of the addition of dried apple pomace to the standard diet. Ruminal pH slightly increased (p &lt; 0.01) while the ammonia concentration decreased (p &lt; 0.01) by 46%. There was a significant decrease in total protozoa count (p &lt; 0.01) and an increase (p &lt; 0.01) in total volatile fatty acids. In addition, there was a decline in methane emission (p = 0.05) by 8% due to dried apple pomace feeding. To sum up, this study demonstrated a positive effect of 150 g/kg DM dietary dried apple pomace on ruminal metabolism including a decrease in ammonia concentration and methane emissions, alongside with an increase in total ruminal VFAs, higher nutrient digestibility, and milk production. Also, beneficial changes to the ruminal fatty acid profile resulting from reduced biohydrogenation were observed although a decreased content of the C18:2 cis 9 trans 11 isomer was also noticed. The dietary inclusion of DAP can serve as a valuable, sustainable, and environmentally friendly dietary component for dairy cows.

Crystal Structures of Bacterial Pectin Methylesterases Pme8A and PmeC2 from Rumen Butyrivibrio.

Pectin is a complex polysaccharide that forms a substantial proportion of the plant's middle lamella of forage ingested by grazing ruminants. Methanol in the rumen is derived mainly from methoxy groups released from pectin by the action of pectin methylesterase (PME) and is subsequently used by rumen methylotrophic methanogens that reduce methanol to produce methane (CH4). Members of the genus Butyrivibrio are key pectin-degrading rumen bacteria that contribute to methanol formation and have important roles in fibre breakdown, protein digestion, and the biohydrogenation of fatty acids. Therefore, methanol release from pectin degradation in the rumen is a potential target for CH4 mitigation technologies. Here, we present the crystal structures of PMEs belonging to the carbohydrate esterase family 8 (CE8) from Butyrivibrio proteoclasticus and Butyrivibrio fibrisolvens, determined to a resolution of 2.30 Å. These enzymes, like other PMEs, are right-handed β-helical proteins with a well-defined catalytic site and reaction mechanisms previously defined in insect, plant, and other bacterial pectin methylesterases. Potential substrate binding domains are also defined for the enzymes.

Modulating Natural Methane Release from Rumen Fermentation through the Use of Ficus glomerata Leaf Tannins in Murrah Buffalo (Bubalus bubalis)

Enteric fermentation is one of the largest contributors of methane release to the environment from the livestock sector. Plant bioactive compounds can modulate rumen fermentation for reduced methanogenesis and fatty acid biohydrogenation. The present study investigates the effects of tannin extract from Ficus glomerata (FG) leaves on the rumen fermentation, methanogenesis, feed digestibility and fatty acid biohydrogenation of a total mixed ration with the aim of developing a feed supplement for enhanced livestock production and product quality with lower methane emission. The tannin extract (70% aqueous acetone extract) of FG leaves in the total mixed ration (oat hay/concentrate mixture; 1:1) was studied at four graded dose regimens (0.0 (control), 0.25 mL (FG-0.25), 0.50 mL (FG-0.50) and 1.0 mL (FG-1.0) per 60 mL of buffered rumen fluid) in three replicates for each treatment in a radio-frequency-based automatic gas production system (ANKOM-RF) at 39 °C for 24 h following the standard in vitro gas production protocol. The total gas production (mL or mL/g incubated dry matter (DM)) was gradually reduced (p &lt; 0.01) at dose levels of FG-0.50 and FG-1.0; however, it remained intermediary and comparable (p &gt; 0.05) for FG-0.25 with the control and FG-0.50. Compared to the control, the methane concentration (%) in the head space gas, as well as the total methane production (mL or mL/g DM incubated, or mL/g DM digested), were found to be gradually reduced (p &lt; 0.01) with increasing doses (0.25–1.0 mL) of FG extract. The reduced (p &lt; 0.05) feed degradability at higher levels (0.50–1.0 mL) of FG extract supplementation and the comparative (p &gt; 0.05) effects with the control at a lower level of supplementation (FG-0.25) are suggestive of the dose-responsive detrimental effects of tannins on fibrolytic microbes in the rumen. However, the ammonia concentration decreased (p &lt; 0.05) in all of the incubations compared to the control. Among the volatile fatty acids, acetate remained comparable (p &gt; 0.05) with enhanced (p &lt; 0.05) propionate at a lower dose (FG-0.25); however, a dose-dependent reduction was evident at higher dose levels (FG-0.50 and FG-1.0). The production of stearic acid (C18:0), which is a product of the rumen biohydrogenation process, was reduced (p &lt; 0.05), irrespective of the concentration of the FG extract. Compared to the control, the concentration of t-vaccenic acid (C18:1), which is a precursor of conjugated linoleic acid (CLA) in animal products, was increased in all the FG-extract-supplemented groups. It may be concluded that Ficus glomerata leaf tannins can modulate rumen fermentation for reduced methanogenesis and fatty acid biohydrogenation in a total mixed ration. As a higher level of inclusion negatively affects feed digestibility, a lower dose (0.25 mL FG extract per 60 mL fermentation fluid or 4.17 mL FG extract per L of fermentation fluid) is suggested to achieve desirable effects on methane abatement (30%) and an improvement in fatty acid profiles in animal products.

Inversion of a paradigm: The positive roles of plant phenolics in dairy goat nutrition

The paradigm prevailing in the nineties, based on studies with goats fed tannin-rich browse as sole feed, was that dietary tannins are associated with impaired feed intake, increased fecal loss of N, and impaired NDF digestibility, hence, impaired productivity, with much research aiming at alleviating these negative effects. However, dairy goats fed plant phenolic-rich diets, and supplemented with concentrates will voluntarily ingest diets comprising more than 4% of tannins, without impairment of total feed intake and milk yield. Also, supplementing them with Poly (ethylene-glycol) MW 4000 is not needed. All plant phenolics, including condensed tannins, are partly digested, inferring that phenolic derivatives are absorbed and may reach tissues. In some studies, diets rich in plant phenolics are associated with the production of milk richer in protein and fat, reduced urea content, and improved curdling performance. Feeding goats with plant phenolics-rich diets is generally associated with inhibited bio-hydrogenation (BH) of fatty acids (FA) in the rumen, resulting in decreased saturated FA, increased polyunsaturated FA (PUFA) and, in particular C18:3–n3 but also a modified composition of de novo synthesized FA in goat milk that suggest direct action of phenolics on the mammary gland. Knowledge of the absorption of plant phenolics is still scarce for goats but even modest daily intakes seem to be associated with increased phenolic derivatives and anti-oxidative activity in plasma and milk. Dietary phenolic compounds may induce a local effect in the mammary gland and its production units (the mammary epithelium cells) encompassing increased cellular triglyceride and casein contents, and increased ATP production and non-mitochondrial oxygen consumption. Plant phenolics and their derivatives divert energy to production of milk fat, protein and lactose, with less energy directed to cellular damage control. Dietary plant phenolics are associated with improved goat health and production of healthier milk. In addition, dietary plant phenolics have anti-parasitic properties and are environment-friendly as they decrease gut methane emission and they increase fecal N at the expense of rapidly decomposable urinary N. Therefore, the attitude of scientists towards feeding plant phenolics has evoluted from mostly negative to mostly positive.

Modulation of Murrah Buffalo (Bubalus bubalis) Rumen Functions for In Vitro Fatty Acid Bio-Hydrogenation, Methane Production and Fermentation Pattern of Total Mixed Ration Supplemented with Allium sativum (Garlic) Essential Oils

The potential for plant-origin essential oils to modulate rumen functions for reducing bio-hydrogenation of fatty acids and methane production has been a significant area of research in recent times. This study investigated the effects supplementation of garlic (Allium sativum) essential oils have on in vitro bio-hydrogenation of fatty acids, methanogenesis and fermentation characteristics of total mixed ration in buffalo with the aim of enhancing conjugated linoleic acid (CLA) content in animal products as well as reducing environmental pollution. Allium sativum (AS) essential oils were examined at four levels [0 (Control), 33.33 µL (AS-1), 83.33 µL (AS-2) and 166.66 µL (AS-3) per litre of buffered rumen fluid] in a radio-frequency based automatic gas production system (ANKOM-RF). Two bottles per treatment per run over two incubation runs were undertaken to gain representative results. Oats hay and concentrate mixture (1:1) was used as a substrate (500 ± 5 mg) and incubated with 60 mL of buffered rumen fluid in 250 mL ANKOM bottles fitted with automatic an gas recording system at 39 °C for 24 h, following standard in vitro gas production protocols. The results demonstrated a reduction (p &lt; 0.01) in lipid bio-hydrogenation, measured by lowered saturated fatty acids and enhanced unsaturated fatty acids on the supplementation of AS essential oils, irrespective of the dose levels. Moreover, the increased (p &lt; 0.01) production of trans vaccenic (trans C18:1) acid (TVA) following graded dose supplementations of the AS essential oils increased the production of conjugated linoleic acids (CLA) in animal products. Although, reduced methane production (p &lt; 0.01) was evidenced, the decrease in total gas production and feed digestibility (TDDM) demonstrated the strong antimicrobial properties of AS at all dose levels. The study reveals that the Allium sativam (Garlic) essential oils have the potential to be an agent for the reduction of the rumen biohydrogenation of fatty acids and methanogenesis. However, in vivo examination is necessary to validate the findings and confirm its suitability for use as an additive to enhance nutraceutical and organoleptic properties in animal products.

Dietary Prebiotic Oligosaccharides and Arachidonate Alter the Fecal Microbiota and Mucosal Lipid Composition of Suckling Pigs

BackgroundEarly intestinal development is important to infant vitality, and optimal formula composition can promote gut health. ObjectivesThe objectives were to evaluate the effects of arachidonate (ARA) and/or prebiotic oligosaccharide (PRE) supplementation in formula on the development of the microbial ecosystem and colonic health parameters. MethodsNewborn piglets were fed 4 formulas containing ARA [0.5 compared with 2.5% of dietary fatty acids (FAs)] and PRE (0 compared with 8 g/L, containing a 1:1 mixture of galactooligosaccharides and polydextrose) in a 2 x 2 factorial design for 22 d. Fecal samples were collected weekly and analyzed for relative microbial abundance. Intestinal samples were collected on day 22 and analyzed for mucosal FAs, pH, and short-chain FAs (SCFAs). ResultsPRE supplementation significantly increased genera within Bacteroidetes and Firmicutes, including Anaerostipes, Mitsuokella, Prevotella, Clostridium IV, and Bulleidia, and resulted in progressive separation from controls as determined by Principal Coordinates Analysis. Concentrations of SCFA increased from 70.98 to 87.37 mM, with an accompanying reduction in colonic pH. ARA supplementation increased the ARA content of the colonic mucosa from 2.35–5.34% of total FAs. PRE supplementation also altered mucosal FA composition, resulting in increased linoleic acid (11.52–16.33% of total FAs) and ARA (2.35–5.16% of total FAs). ConclusionsPrebiotic supplementation during the first 22 d of life altered the gut microbiota of piglets and increased the abundance of specific bacterial genera. These changes correlated with increased SCFA, which may benefit intestinal development. Although dietary ARA did not alter the microbiota, it increased the ARA content of the colonic mucosa, which may support intestinal development and epithelial repair. Prebiotic supplementation also increased unsaturation of FAs in the colonic mucosa. Although the mechanism requires further investigation, it may be related to altered microbial ecology or biohydrogenation of FA.

Profiling of Fatty Acids and Rumen Ecosystem of Sheep Fed on a Palm Kernel Cake-Based Diet Substituted with Corn

The purpose of this study was to analyze the effects of corn substitution on the rumen functions and fatty acid profile of Dorper lambs fed a diet based on palm kernel cake (PKC). Corn was replaced with PKC basal diet at the following levels: C0% = (0% corn + 75.3% PKC), C1% = (5% corn + 70.3% PKC) and C2% = (10% corn + 65.3% PKC) of diet. The rumen fermentation was carried out in vitro, and feeding trials were in vivo. Twenty-seven lambs were used to determine gastrointestinal tract content and rumen fluid fatty acid. Rumen liquor was obtained from four fistulae Dorper sheep and incubated with 200 mg of each treatment for 24 and 72 h. In vitro organic matter digestibility (IVOMD), in vitro dry matter digestibility (IVDMD), volatile fatty acids (VFA), methane estimation (CH4), rumen microbial population and fatty acid biohydrogenation were determined. The results of the in vitro study showed there were no significant differences in IVDMD, IVOMD, NH3-N, pH and VFA at 72 h. Higher significant CH4 production was observed in C0% when compared with C1% and C2%. Microbial population did not differ significantly between treatment groups. The rates of biohydrogenation were not affected by corn substitution, although a significant difference was observed in C18:1n9 (in vitro) and C18:1 t-11 (in vivo). In conclusion, the present study indicated that the corn substitution in the PKC diets maintained fermentation characteristics with an increase in unsaturated fatty acids in the rumen.

Effect of Heat Processing of Rubber Seed Kernel on In Vitro Rumen Biohydrogenation of Fatty Acids and Fermentation

The aim of this study was to assess the effect of rubber seed kernel heat processing on in vitro rumen biohydrogenation of fatty acids and fermentation. The experiment was conducted with a completely randomized design (CRD). The inclusion of RSK at 0% (CON) and 20% with different processing methods as follows: Raw rubber seed kernel (RAWR), roasted rubber seed kernel (ROR), microwave irradiated rubber seed kernel (MIR), and rubber seed kernel were heated in a hot air oven (RHO) in total mixed ration (TMR) diets. The hydrogen cyanide (HCN) was reduced using RSK heat methods. The heat processing of RSK had no effect on cumulative gas production at 96 h, the gas production from the insoluble fraction (b), or degradability (p &gt; 0.05), whereas it reduced the gas production from the immediately soluble fraction (a) and constant rate of gas production for the insoluble fraction (c) (p &lt; 0.01). The RSK processing methods did not influence ruminal pH, total volatile fatty acid (VFA), or VFA proportions (p &gt; 0.05). RSK heat processing reduced ammonia-nitrogen (NH3-N) (p &lt; 0.04) while increasing the bacterial population (p &lt; 0.02). Heat treatment had no effect on linoleic acid (C18:2 cis-9,12 + tran-9,12) (p &gt; 0.05). The RHO increases oleic acid (C18:1 cis-9 + tran-9) and linolenic acid (C18:3 cis-9,12,15) concentrations (p &lt; 0.01). In conclusion, RHO reduced rumen biohydrogenation of unsaturated fatty acids (UFA), especially C18:3 and C18:1.

Integrating data from spontaneous and induced trans-10 shift of ruminal biohydrogenation reveals discriminant bacterial community changes at the OTU level.

Microbial digestion is of key importance for ruminants, and disturbances can affect efficiency and quality of products for human consumers. Ruminal biohydrogenation of dietary unsaturated fatty acids leads to a wide variety of specific fatty acids. Some dietary conditions can affect the pathways of this transformation, leading to trans-10 fatty acids rather than the more usual trans-11 fatty acids, this change resulting in milk fat depression in dairy cows. We combined data from an induced and spontaneous trans-10 shift of ruminal biohydrogenation, providing new insight on bacterial changes at different taxonomic levels. A trans-10 shift was induced using dietary addition of concentrate and/or unsaturated fat, and the spontaneous milk fat depression was observed in a commercial dairy herd. Most changes of microbial community related to bacteria that are not known to be involved in the biohydrogenation process, suggesting that the trans-10 shift may represent the biochemical marker of a wide change of bacterial community. At OTU level, sparse discriminant analysis revealed strong associations between this change of biohydrogenation pathway and some taxa, especially three taxa belonging to [Eubacterium] coprostanoligenes group, Muribaculaceae and Lachnospiraceae NK3A20 group, that could both be microbial markers of this disturbance and candidates for studies relative to their ability to produce trans-10 fatty acids.

Effect of inclusion of distillers grains with solubles and crude glycerin in beef cattle finishing diets on ruminal fermentation and fatty acid biohydrogenation.

An experiment was conducted to evaluate the impact of feeding bio-fuel co-products on ruminal fermentation characteristics and composition of omasal digesta flow. Four ruminally cannulated Holstein steers (371 ± 5 kg) were used in a 4 × 4 Latin Square design. Omasal sample collection and triple marker technique was used to quantify fatty acid omasal flow. Treatments were applied as a 2 × 2 factorial where a steam flaked corn (SFC) basal diet (DGS-N CG-N) was replaced with 40% of diet DM as corn distillers grains (DGS; DGS-Y CG-N) or 10% of diet DM as crude glycerin (DGS-N CG-Y) or 40% of diet DM distillers grains and 10% of diet DM as crude glycerin (DGS-Y CG-Y). No effects were observed for the interaction of DGS and glycerin on measured rumen characteristics. Dietary inclusion of glycerin decreased (P = 0.05) ruminal content 4-h post feeding on a DM basis but did not influence DMI (P = 0.64). Feeding DGS had no effect (P = 0.34) on particulate passage to the omasum (kg/d) in spite of greater (P = 0.04) DMI. Feeding DGS reduced flow rate (% of rumen volume/h) (P = 0.05) but did not affect total VFA concentration (P = 0.46) or average ruminal pH (P = 0.72). No differences (P > 0.05) were observed in ruminal parameters when feeding glycerin, besides ruminal particulate content (kg) on DM basis (P = 0.05). An interaction of DGS and glycerin affected intake of stearic (P < 0.01), linoleic (P < 0.01), and linolenic acid (P < 0.01). An interaction of DGS and glycerin did not affect individual fatty acid flow with respect to intake for stearic (P = 0.17), linoleic (P = 0.18), or linolenic acid (P = 0.66). Dietary inclusion of glycerin had no impact on g of linolenic (P = 0.16) or linoleic (P = 0.32) acid transformed. A trend was identified for cattle fed diets with glycerin to have increased (P = 0.07) grams of conjugated linoleic acid (CLA; C18:2 cis-9, trans-11) per gram of linoleic acid intake, with no impact on the percent of saturated fat (P = 0.44) or unsaturated fat (P = 0.43) in omasal flow. For cattle fed diets with DGS, fewer grams of linoleic (P < 0.01) and linolenic (P < 0.01) were present in digesta flow per gram of intake. Inclusion of DGS in the treatment diets also increased (P < 0.01) stearic acid flow (g) and CLA flow (g) per gram of stearic and linoleic acid intake, respectively. Observed differences in CLA proportion post fermentation may indicate interrupted biohydrogenation when glycerin is fed.

Condensed tannins to increase bioactive fatty acids in the milk from Canindé, Repartida, and Saanen goats.

Bioactive fatty acids present in goat milk have the ability to reduce the risks of coronary heart disease in humans, and condensed tannins (CT) can modulate the polyunsaturated fatty acids (PUFA) biohydrogenation process in the rumen and consequently increase the levels of these fatty acids. Thus, the objective was to evaluate the inclusion of CT in the diet for Canindé, Repartida, and Saanen goats to increase the level of bioactive fatty acids in milk. Twenty-two lactating does of three genetic groups, six Canindé, eight Repartida, and eight Saanen, were randomly assigned in a 3 × 2 factorial arrangement of three genetic groups and two diets (control and with 50g CT/kg DM). The inclusion of CT in the diet did not change (P > 0.05) nutrient intake and performance. However, the inclusion of CT promoted an increase (P < 0.05) in C14:1; cis-9; C18:2n6; C18:3n6; C18:3n3; PUFA; and long-chain fatty acids and reduction (P < 0.05) of C11; C12; C14; ω6/ω3; and atherogenicity index in milk fat. Thus, it is recommended to include CT in the diet for Canindé, Repartida, and Saanen goats to increase the level of bioactive fatty acids in milk. The inclusion of the tannins of Acacia mearnsii promoted an increase in C14:1; cis-9; C18:2n6; C18:3n6; C18:3n3; polyunsaturated fatty acid; and long-chain fatty acids and reduction of C11; C12; C14; ω6/ω3; and atherogenicity index in milk fat.