Search

Trans vaccenic acid (TVA, trans11-18 : 1) and cis9, trans11-CLA (also known as rumenic acid; RA) have received widespread attention as potentially beneficial trans-FA due to their putative health benefits, including anti-diabetic properties. The objective of this study was to determine the effects of beef fat naturally enriched with TVA and RA on parameters related to glucose homoeostasis and associated metabolic markers in diet-induced obese (DIO) mice. Thirty-six male C57BL/6J mice (8 weeks old) were fed for 19 weeks with either a control low-fat diet (CLF), a control high-fat diet (CHF), or a TVA+RA-enriched high-fat diet (EHF). Compared with CLF, feeding either CHF or EHF resulted in adverse metabolic outcomes associated with high-fat diets, including adiposity, impaired glucose control and hepatic steatosis. However, the EHF diet induced a significantly higher liver weight TAG content and elevated plasma alanine transaminase levels compared with the CHF diet. Collectively, the findings from this study suggest that EHF does not improve glucose tolerance and worsens liver steatosis in DIO mice. However, the adverse effects of EHF on the liver could be in part related to the presence of other trans-FA in the enriched beef fat.

This study aimed to evaluate the effects of rumen-protected fat (RPF) on in vitro fermentation profiles and biohydrogenation of fatty acids. The treatment diets were basal diet (70:30 concentrate to rice straw) with no RPF (CON), basal diet plus prilled fat (PF), basal diet plus prilled fat with lecithin (PFL) and basal diet plus calcium soap of palm fatty acids (CaS). In vitro gas production, fermentation kinetics, in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD), metabolizable energy (ME), rumen fermentation and fatty acid profile were determined. The results show that RPF did not affect cumulative gas production and gas production kinetics. PFL significantly (p < 0.05) improved IVDMD and IVOMD, although the addition of RPF did not affect ME. The volatile fatty acid (VFA), pH, ammonia nitrogen, methane, and molar proportion of VFA were not significantly influenced by the RPF; methane was numerically reduced because of PFL treatment. The concentration of monounsaturated and polyunsaturated fatty acids increased (p < 0.05) whereas that of saturated fatty acids decreased in the control diet. The biohydrogenation of C18:2n-6 and C18 unsaturated fatty acids was enhanced (p < 0.05) by PFL. These findings suggest that PFL enhances gas production, decreases methane and increases the biohydrogenation of C18:2n6 without disrupting rumen fermentation.

Trans vaccenic acid (TVA, trans 11–18 : 1) and cis 9, trans 11-CLA (also known as rumenic acid; RA) have received widespread attention as potentially beneficial trans -FA due to their putative health benefits, including anti-diabetic properties. The objective of this study was to determine the effects of beef fat naturally enriched with TVA and RA on parameters related to glucose homoeostasis and associated metabolic markers in diet-induced obese (DIO) mice. Thirty-six male C57BL/6J mice (8 weeks old) were fed for 19 weeks with either a control low-fat diet (CLF), a control high-fat diet (CHF), or a TVA+RA-enriched high-fat diet (EHF). Compared with CLF, feeding either CHF or EHF resulted in adverse metabolic outcomes associated with high-fat diets, including adiposity, impaired glucose control and hepatic steatosis. However, the EHF diet induced a significantly higher liver weight TAG content and elevated plasma alanine transaminase levels compared with the CHF diet. Collectively, the findings from this study suggest that EHF does not improve glucose tolerance and worsens liver steatosis in DIO mice. However, the adverse effects of EHF on the liver could be in part related to the presence of other trans -FA in the enriched beef fat. [ABSTRACT FROM AUTHOR]

Abstract Background Rubber 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. Results The supplementation with RUSKEP had no effect on gas kinetics, cumulative gas production, or degradability. Ruminal pH decreased linearly (P

ABSTRACT: 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.

Introduction: Medicinal plants, rich in phytochemicals like phenolic acids, flavonoids, and tannins, offer potential benefits in enhancing productivity, quality, and animal health. Amla fruit (Phyllanthus emblica) is one such plant with promising attributes. This study aimed to investigate the impact of fresh Amla fruit (FAF) supplementation on ruminal microbial composition and its correlation with rumen fermentation in lactating dairy cows. Methods: The study employed a repeated crossover design involving eight ruminally cannulated mid-lactation Holstein dairy cows. Animals received varying levels of fresh Amla fruit supplementation (0, 200, 400, and 600 g/d). Results: When 400 g/d of FAF was added to the diet, there was a significant increase in the relative abundance of Firmicutes (p = 0.02). However, at 200 g/d, the relative abundance of ruminal Bacteroidota was higher than the 0 and 400 g/d FAF supplementation (p < 0.01). LEfSe analysis identified distinct taxa, such as Clostridia vadinBB60 in the 200 g/d group, Oscillospiraceae in the 400 g/d group, and Elusimicrobium in the 600 g/d group. Notably, the random forest species abundance statistics identified Oscillospiraceae V9D2013 as a biomarker related to milk yield. Oscillospiraceae, Bacilli RF39, norank_f Prevotellaceae, and Bifidobacterium were positively correlated with ruminal total VFA and molar proportion of propionate, while Rikenellaceae RC9 gut group and Clostridia vadinBB60 were negatively correlated. Discussion: FAF supplementation affects the abundance of beneficial microbes in a dose-dependent manner, which can improve milk yield, efficiency, rumen health, desirable fatty acids, and animal health. [ABSTRACT FROM AUTHOR]

Introduction: Medicinal plants, rich in phytochemicals like phenolic acids, flavonoids, and tannins, offer potential benefits in enhancing productivity, quality, and animal health. Amla fruit (Phyllanthus emblica) is one such plant with promising attributes. This study aimed to investigate the impact of fresh Amla fruit (FAF) supplementation on ruminal microbial composition and its correlation with rumen fermentation in lactating dairy cows. Methods: The study employed a repeated crossover design involving eight ruminally cannulated mid-lactation Holstein dairy cows. Animals received varying levels of fresh Amla fruit supplementation (0, 200, 400, and 600 g/d). Results: When 400 g/d of FAF was added to the diet, there was a significant increase in the relative abundance of Firmicutes (p = 0.02). However, at 200 g/d, the relative abundance of ruminal Bacteroidota was higher than the 0 and 400 g/d FAF supplementation (p < 0.01). LEfSe analysis identified distinct taxa, such as Clostridia vadinBB60 in the 200 g/d group, Oscillospiraceae in the 400 g/d group, and Elusimicrobium in the 600 g/d group. Notably, the random forest species abundance statistics identified Oscillospiraceae V9D2013 as a biomarker related to milk yield. Oscillospiraceae, Bacilli RF39, norank_f Prevotellaceae, and Bifidobacterium were positively correlated with ruminal total VFA and molar proportion of propionate, while Rikenellaceae RC9 gut group and Clostridia vadinBB60 were negatively correlated. Discussion: FAF supplementation affects the abundance of beneficial microbes in a dose-dependent manner, which can improve milk yield, efficiency, rumen health, desirable fatty acids, and animal health. [ABSTRACT FROM AUTHOR]

Background: Rubber 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. Results: The 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). Conclusions: Adding up to 10% of RUSKEP could improve in vitro rumen fermentation and C18 unsaturated fatty acids, especially ALA, in swamp buffalo. [ABSTRACT FROM AUTHOR]

Asparagopsis taxiformis inhibits ruminal methane (CH 4) production due to its bromoform (CHBr 3) content. The immersion of A. taxiformis in edible vegetable oils allows the extraction and stabilization of the highly volatile CHBr 3 in the oil phase. The objectives of this study were to explore the effects of adding sunflower oils with increasing concentrations of CHBr 3 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 CHBr 3 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 CHBr 3 per gram of substrate DM. Organic matter (OM) degradability, total gas, CH 4 , 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 CHBr 3 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 CHBr 3 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 CHBr 3 -containing treatments, although without any dose-response pattern. The molar percentage of acetate decreased linearly, whereas propionate and butyrate increased linearly with the increasing CHBr 3 dosage. Including oil in the diet decreased the branched-chain fatty acids and DMA content. Increasing CHBr 3 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 CHBr 3 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 CH 4 in vitro at doses of 100 and 150 μg/g DM, and simultaneously modulate biohydrogenation. [ABSTRACT FROM AUTHOR]

The effect and conversion of diets containing water-washed neem (Azadirachta indica A. Juss) fruit (WN) biomass as substantiable feed resource was determined on rumen microbial population, fermentation, and meat fatty acid profile of fattened West African dwarf rams. One-year old, individually housed rams (N = 25; 12.3 ± 2.0 kg), five per treatment, were allocated in a completely randomized design to one of the five dietary treatments. Each treatment received 0 (WN0), 2.5 (WN2.5), 5 (WN5), 7.5 (WN7.5), and 10 (WN10) % of WN (% dry matter) of complete diet offered for 90 days. Rumen liquor was collected 4 h post feeding for microbial and fermentation assay while Longissimus dorsi muscle was taken after slaughtering the animal for fatty acids (FAs) determination, post feeding trial. Inclusion of WN initially increased but subsequently reduced (P < 0.05) the population of bacteria and fungi but consistently reduced the population of protozoa. The WN decreased NH3-N in WN7.5 and WN10 compared to other treatments. Propionate was higher in WN5 compared to the control. There was increased concentration of meat linolenic, vaccenic, rumenic, oleic, and lauric FAs in WN10 than WN0. Dietary inclusion of WN increased (P < 0.05) the constituent of unsaturated fatty acids, and total desaturase index in WN5 compared to other treatments. Incorporation of water-washed neem fruit beyond 5% reduced rumen microbial population, ammonia nitrogen, and propionate with increased unsaturated fatty acids including rumenic acid, a conjugated linoleic acid known for its health promoting benefits. This imply that at 5% inclusion of water-washed neem fruit biomass there was better substantiable feed resource for stimulation of microbial growth for increased microbial protein production for host's growth, efficiency in energy use, and the consumption of functional food. [ABSTRACT FROM AUTHOR]

Few studies have evaluated the impact of a lipid-rich diet with palmitic acid (PA) in ruminal fermentation. The objective was to evaluate the in vitro bath culture of the protected PA on the ruminal fermentative variables. Four diets were used: (a) without protected PA (nPA) and (b) inclusion of protected PA at three levels: PA3 = 3%, PA6 = 6%, and PA9 = 9% dry matter (DM). The maximum gas production occurred without including protected PA and the low gas production given with the inclusion of protected PA9 (p ≤ 0.05). Meanwhile, the inclusion with 3 and 6% of protected PA showed a higher level of gas production kinetics than the other treatments (p ≤ 0.05). DM and organic matter degradation after 72 h of incubation linearly decreased (p ≤ 0.05) with a high level of protected PA. The level of C16:0 in the protected AP increased with the higher level of supplemented AP (p ≤ 0.05). The best efficiency in propionic acid, decrease in methane, and increase in biohydrogenation (79%) occurred with the inclusion of protected PA3 (p ≤ 0.05). In conclusion, supplements with protected PA at 3 and 6% increased PA availability. The results indicate good benefits of protected PA on fermentative variables, and these doses seem ideal for future research in lactating goats. [ABSTRACT FROM AUTHOR]

In order to determine the effects of sodium acetate and conjugated linoleic acid (CLA) on dry matter consumed, feed digestibility, milk yield and milk fat profile, 33 Holstein cows several calving times during days 5-31 after calving in a completely randomized design with Three treatments and 11 replications were used. The experimental diets included 1-basic diet (control), 2- diet containing 300 gr of sodium acetate, 3- diet containing 100 gr of CLA. Daily dry matter intake and milk production, body weight and body condition score were measured at the beginning and end of the experiment. milk samples were taken at regular intervals to determine the amount of milk compounds. Also, on the last day, a sample was taken to determine the profile of fatty acids. Dry matter intake was not significant among dietary treatment (P>0.05). Milk production was increased by supplementing diets with sodium acetate (3.16 kg/d) and CLA (2.46 kg/d) compared to control treatment. CLA supplementing decreased milk fat content significantly and sodium acetate increased it. The yield and content of milk protein and lactose were not significantly different between the treatments. With the consumption of sodium acetate, the amount of milk fat and milk production increased, as probably the hypothesis that sodium acetate is lipogenic for adipose tissue was ignored and Acetate partition nutriunt toward milk fat production. CLA consumtion, negative energy balance did not change between as spared energy partition toward more milk yield. The use of CLA could be beneficial for the health of consumers by increasing the trans-10-cis-12 CLA isomer transfer to milk and reducing thrombogenic and atherogenic indicators. [ABSTRACT FROM AUTHOR]

Featured Application: Livestock significantly contribute to greenhouse gas emissions, with methane production from animals like cows, sheep, and goats being a major concern. Reducing this methane output is crucial for environmental sustainability. There is also a growing interest in enhancing the nutritional quality of meat and milk from these animals. This study investigated the potential of natural additives—sage (SAG), pine (PIN), and clove (CLO) essential oils—to manipulate ruminal fermentation as well as biohydrogenation of polyunsaturated fatty acids (PUFA). The research focused on ruminal gas production, methane emissions, and fatty acid changes using in vitro methods. The essential oils led to lower gas and methane production. Additionally, they affected rumen pH, ammonia levels, and fatty acid profiles. These findings suggest that SAG, PIN, and CLO might reduce methane emissions and improve product quality in livestock. More research is needed to apply these findings practically. 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. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of plant bioactive compounds like tannins to modulate ruminal biohydrogenation is a good strategy to optimize the fatty acid composition of ruminant-derived products, which are closely associated with human health. Differently from terrestrial tannins, there is little information on the effect of phlorotannins (PTs) from brown seaweeds on ruminal biohydrogenation. Thus, this study aimed to evaluate the effect of PT extract from Sargassum on in vitro rumen fermentation, fatty acid composition and bacterial community. The inclusion of PT extract had a positive effect on rumen fermentation by increasing dry matter digestibility and gas production and reducing ammonia-N concentration. Rumen biohydrogenation was profoundly inhibited by PTs as reflected in an increased unsaturated fatty acid and reduced saturated fatty acid production. The addition of PTs also changed the rumen bacterial community significantly with elevated carbohydrate-mediated bacteria. Correlation analysis found that Prevotellaceae_UCG-001, Anaerovorax, Ruminococcus, Ruminobacter, Fibrobacter, Lachnospiraceae_AC2044_group and Clostridia_UCG-014 might be involved in the biohydrogenation process. The results suggest that the inclusion of PTs in the diet improved rumen fermentation and fatty acid composition through modulating rumen microbiota. The fatty acid profiles of ruminant-derived products are closely associated with human health. Ruminal microbiota play a vital role in modulating rumen biohydrogenation (BH). The aim of this study was to assess the influence of dietary supplementation with phlorotannins (PTs) extracted from Sargassum on rumen fermentation, fatty acid composition and bacterial communities by an in vitro culture study. The inclusion of PTs in the diet increased dry matter digestibility and gas production, and reduced ammonia-N concentration and pH. PT extract inhibited rumen BH, increasing the content of trans-9 C18:1, cis-9 C18:1, trans-9 and trans-12 C18:2 and reducing C18:0 concentration. 16S rRNA sequencing revealed that PTs caused an obvious change in rumen bacterial communities. The presence of Prevotella decreased while carbohydrate-utilizing bacteria such as Prevotellaceae_UCG-001, Ruminococcus, Selenomonas, Ruminobacter and Fibrobacter increased. Correlation analysis between rumen FA composition and the bacterial microbiome revealed that Prevotellaceae_UCG-001, Anaerovorax, Ruminococcus, Ruminobacter, Fibrobacter, Lachnospiraceae_AC2044_group and Clostridia_UCG-014 might have been involved in the BH process. In conclusion, the results suggest that the inclusion of PTs in the diet improved rumen fermentation and FA composition through modulating the rumen bacterial community. [ABSTRACT FROM AUTHOR]

Introduction: 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. Materials and methods: 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. Results and discussion: 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. [ABSTRACT FROM AUTHOR]

The use of alternative feed ingredients from the Agro-industry could be an efficient tool to improve the sustainability of dairy cow production. Since the richness in polyphenols, olive oil pomace (OOP), produced during olive oil milling, seems a promising by-product to ameliorate milk’s nutritional value. The aim of this study was to test the use of OOP produced by means of a new technology (biphasic with stone deprivation) in dairy cow feeding strategy to evaluate the effect on animal performances, rumen microbiota, biohydrogenation processes and milk quality by a multidisciplinary approach. Forty multiparous Italian-Friesian dairy cows, at middle lactation, were randomly allotted into two homogenous groups and fed respectively a commercial diet (CON) and the experimental diet (OOPD) obtained by adding OOP to CON as partial replacement of maize silage. The two diets were formulated to be isoproteic and isoenergetic. The same diets were tested also in an in vitro trial aimed to evaluate their rumen degradability (% DEG). The dietary supplementation with OOP did not affect DM intake, rumen % DEG and milk production. The milk’s nutritional quality was improved by increasing several important functional fatty acids (FAs; i.e., linoleic acid, conjugated linoleic acid, oleic acid, vaccenic acid). This finding was related to a decrease in rumen liquor biohydrogenation rate of unsaturated FAs. The stochiometric relation between volatile FA production in the rumen and methanogenesis suggested that OOP lowers the methane potential production (CON = 0.050 mol/L vs OOPD = 0.024 mol/L, SEM = 0.005, P = 0.0011). Rumen microbiota and fungi community did not be strongly altered by OOP dietary inclusion because few bacteria were affected at the genus level only. Particularly, Acetobacter, Prevotellaceae_UCG-004, Prevotellaceae_UCG-001, Eubacterium coprostanoligenes, Lachnospira, Acetitomaulatum, Lachnospiraceae_NK3A20 group were more abundant with OOPD condition (P

Few studies have evaluated the impact of a lipid-rich diet with palmitic acid (PA) in ruminal fermentation. The objective was to evaluate the in vitro bath culture of the protected PA on the ruminal fermentative variables. Four diets were used: (a) without protected PA (nPA) and (b) inclusion of protected PA at three levels: PA3 = 3%, PA6 = 6%, and PA9 = 9% dry matter (DM). The maximum gas production occurred without including protected PA and the low gas production given with the inclusion of protected PA9 (p ≤ 0.05). Meanwhile, the inclusion with 3 and 6% of protected PA showed a higher level of gas production kinetics than the other treatments (p ≤ 0.05). DM and organic matter degradation after 72 h of incubation linearly decreased (p ≤ 0.05) with a high level of protected PA. The level of C16:0 in the protected AP increased with the higher level of supplemented AP (p ≤ 0.05). The best efficiency in propionic acid, decrease in methane, and increase in biohydrogenation (79%) occurred with the inclusion of protected PA3 (p ≤ 0.05). In conclusion, supplements with protected PA at 3 and 6% increased PA availability. The results indicate good benefits of protected PA on fermentative variables, and these doses seem ideal for future research in lactating goats.

Our objective was to investigate the contribution of the rumen microbiome on the individual milk fat percentage (MFP) of Holstein dairy cows under the same nutritional and management conditions. From 92 early lactation dairy cows, the top 10 with the highest MFP (HF; n = 10) and the last 10 with the lowest MFP (LF; n = 10) were selected for the study. As a result, the milk trans-10, cis-12 C18:2 content was significant lower in the HF group than that in the LF group (P < 0.001). The rumen acetate to propionate ratio was significant higher in the HF group than that in the LF group (P = 0.035). According to the results of 16S rRNA gene sequencing, a minor but significant difference existed between the groups (P = 0.040). Three genera of the family Lachnospiraceae and four genera of the order Bacteroidales were identified to be the biomarkers for the LF group and HF group in the LEfSe analysis, respectively. Three microbial modules enriched by the family Lachnospiraceae were positively related to the milk trans-10, cis-12 C18:2 content (rs > 0.60, P < 0.05). According to the results of shotgun metagenome sequencing, three kinds of linoleic acid (LA) isomerase genes were present in the gene pools of the rumen microbiome. Among them, the relative abundance of Bifidobacterium LA isomerase (BBI) was higher in the HF group than that in the LF group (P = 0.007). Three metagenome-assembled genomes (MAGs) with LA isomerase genes were positively correlated to the milk trans-10, cis-12 C18:2 content (rs> 0.40, P < 0.05). Furthermore, all of these three MAGs were found to be able to produce lactate. Taken together, these results indicate that the increased relative abundance of microbial population with the trans-10 biohydrogenation pathway within the rumen microbiome contributes to the decrease of MFP via the increase of rumen trans-10, cis-12 C18:2 production. This study provides a new perspective for the development of measures for improving the milking performance of dairy cows.

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 > 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 < 0.01). The RSK processing methods did not influence ruminal pH, total volatile fatty acid (VFA), or VFA proportions (p > 0.05). RSK heat processing reduced ammonia-nitrogen (NH3-N) (p < 0.04) while increasing the bacterial population (p < 0.02). Heat treatment had no effect on linoleic acid (C18:2 cis-9,12 + tran-9,12) (p > 0.05). The RHO increases oleic acid (C18:1 cis-9 + tran-9) and linolenic acid (C18:3 cis-9,12,15) concentrations (p < 0.01). In conclusion, RHO reduced rumen biohydrogenation of unsaturated fatty acids (UFA), especially C18:3 and C18:1. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Context: In recent years, microalgae have been used in the diet to improve the quality of animal products due to their oil content and quality, but determining the optimum dose is very important to prevent some fermentation and economic losses in animal production. Aims: The study investigated the effects of microalga (DHA-gold) supplementation in the diet at different levels in in vitro ruminal biohydrogenation and fermentation. Methods: The treatments were control (no additional oil, forage:concentrate ratio 60:40 on a dry-matter (DM) basis) or the addition of 1%, 2%, and 3% of microalga in the diet on a DM basis. Four rumen-cannulated goats were used as donors for the in vitro experiment. The treatments were incubated using a batch culture technique, and the fatty acid profile and fermentation parameters were determined after 0, 3, 6, 12, and 24 h. Key results: Total conjugated linoleic acids (CLA), cis-9, trans-11 CLA and trans-11 C18:1 fatty acids increased with supplementation of microalgae. The 24-h biohydrogenation rate of unsaturated fatty acids varied between 61% and 98%. In addition, the highest CLA content was obtained from the 3% algae group. Biohydrogenation of C18:3, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) fatty acids was decreased with the 2% microalga supplementation. The microalga supplementation had no effect on ruminal pH, ruminal acetate, propionate, and butyrate proportions, or the acetate:propionate ratio. Conclusion: Under the current in vitro study conditions, 2% microalga supplementation to diet increased the ruminal biohydrogenation intermediate products, such as total CLA and trans-11 C18:1 fatty acid and decreased the ruminal biohydrogenation ratio of n-3 fatty acids (C18:3, EPA, and DHA). Implications: Increasing the bioactive and beneficial fatty acids (e.g. CLAs) that are absorbed in the rumen by ruminants and then transferred to animal products (meat, milk) is important. From the results of this in vitro study, dietary microalga increased the ruminal CLA, C18:3, EPA, and DHA concentrations. However, dietary fat level should be evaluated in terms of improving an animal's performance (growth rate, digestibility, milk yield, carcass, and milk quality). Diseases related to consumption of animal products have come to the fore today and it is important to increase product quality. In this study, changes were made to animal feeds so as to increase some fatty acids, which have significant positive effects on health. This change was achieved by adding a rich source of omega 3 to the diet, which has been used frequently in recent years, and the most appropriate dose was determined for adding this source to the diet. [ABSTRACT FROM AUTHOR]

[Display omitted] • Free ammonia from hydrolysis of chicken manure promoted the hydrogenic fermentation. • Increased organic loading rate resulted in an increase of the hydrogen production. • Romboutsia (19.7 %) and Clostridium (16.6 %) were the dominant strains. • Biochar derived from solid digestate fraction was rich in calcium and phosphorus. • Bioaugmentation of liquid digestate removed 83.3 % of NH 4 -N and 66.2 % of COD. This study provides a sustainable approach to produce biohydrogen through the long-term hydrogenic fermentation of chicken manure (CM) in a semi-continuous stirred tank reactor (CSTR) under different organic loading rates (OLRs). To ensure the zero-waste route and sustainability , the total digestate was mechanically separated into liquid and solid fractions. The solid digestate fraction was thermally treated to produce biochar, while the liquid digestate fraction was biologically treated through bioaugmentation with a novel heterotrophic nitrification-aerobic denitrification (HD-AN (bacterial strain (Alcaligenes sp. ME-1). The results showed that the high concentration of free ammonia nitrogen (FAN) contents of CM could inhibit methanogenesis and induce hydrogen production. The ORLs of 2.5, 3.5, 4.5, and 5.5 gVS/L.d imposed to the CSTR resulted in volumetric hydrogen production (VHP) of 643.3 ± 37, 908.8 ± 64.5, 1077.8 ± 95.17, and 1383.3 ± 156.8 mL/L.d, respectively. The microbial community structures indicated the long-term adaptation of hydrogen-producing bacteria and methanogenesis inhibition. The bioaugmentation process removed 83.3 % of total ammonia and 66.2 % of the chemical oxygen demand (COD) from the liquid digestate fraction. The characteristics of the biochar derived solid digestate is suitable for land applications as fertilizer. The hybrid approach combining biohydrogenation, pyrolysis, and bioaugmentation, maximizes the utilization of chicken manure slurry while conforming to the sustainable development goals. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine the impact of copper (Cu) dose on microbial fermentation products and biohydrogenation of soybean oil (SBO) using an in vitro rumen fermentation technique. Two heifers [body weight (BW) = 408 and 422 kg] fitted with ruminal canulae were fed a high concentrate diet for 14 d. On d 15, rumen fluid samples were obtained 2 h post-feeding from both animals and combined into one pre-warmed (39°C) container. Anaerobic conditions were maintained by bubbling carbon dioxide (CO2) into McDougall’s buffer, while two volumes of rumen fluid were added to each volume of McDougall’s buffer. The suspension was mixed under CO2 as 30-mL portions were added to pre- weighed vaccine bottles containing 0.5 g of substrate (ground basal finishing diet with no supplemental Cu or SBO). The basal diet contained 4.2 mg Cu/kg dry matter (DM). Treatments were assigned to vaccine bottles in a 2 x 3 factorial arrangement with factors being SBO (0 or 3.5%) and Cu (0, 10, or 20 mg/kg DM) relative to substrate DM. Each treatment was replicated 6 times. Following treatment administration, all vaccine bottles were caped and sealed to maintain anaerobic condition and incubated at 39°C. Vaccine bottles were swirled by hand at the time of gas sample collection at 0, 2, 4, 6, 8, 10, 12, 18, 24, 36, and 48 h post-inoculation. Samples were immediately analyzed for methane (CH4) and CO2. Following every gas sampling timepoint, the vaccine bottles were degassed. At the end of the 48-h incubation, all vaccine bottles were centrifuged, and 2 mL of supernatant were removed and acidified with 25% metaphosphoric acid for volatile fatty acid (VFA) determination, and another 5 mL of supernatant were removed and analyzed for long chain fatty acids. The remaining supernatant was decanted, and the vaccine bottles were dried at 60°C for 72 h to determine DM disappearance (DMD). Data were analyzed as a randomized block design for a 2 x 3 factorial arrangement of treatment using PROC MIXED of SAS. Forty-eight hour DMD, CO2 production, molar percent of acetate, propionate, and butyrate, total mM of VFA, and pH were unaffected by treatment. Methane production per unit of DMD decreased (P < 0.05) in fermentation bottles containing SBO but increased (P < 0.04) in fermentation bottles containing Cu. Soybean oil addition increased C16:0, C18:0, C18:1, C18:2, and C18:3 fatty acids at 48 h. Copper addition tended to decrease C18:0 (P < 0.07) and tended to increased C18:1 (P < 0.06) and C18:3 (P < 0.09) fatty acids. These data suggest that Cu may decrease biohydrogenation in vaccine bottles not containing SBO but increases ruminal biohydrogenation in vaccine bottles containing SBO. [ABSTRACT FROM AUTHOR]

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.

The fatty acid profiles of ruminant-derived products are closely associated with human health. Ruminal microbiota play a vital role in modulating rumen biohydrogenation (BH). The aim of this study was to assess the influence of dietary supplementation with phlorotannins (PTs) extracted from Sargassum on rumen fermentation, fatty acid composition and bacterial communities by an in vitro culture study. The inclusion of PTs in the diet increased dry matter digestibility and gas production, and reduced ammonia-N concentration and pH. PT extract inhibited rumen BH, increasing the content of trans-9 C18:1, cis-9 C18:1, trans-9 and trans-12 C18:2 and reducing C18:0 concentration. 16S rRNA sequencing revealed that PTs caused an obvious change in rumen bacterial communities. The presence of Prevotella decreased while carbohydrate-utilizing bacteria such as Prevotellaceae_UCG-001, Ruminococcus, Selenomonas, Ruminobacter and Fibrobacter increased. Correlation analysis between rumen FA composition and the bacterial microbiome revealed that Prevotellaceae_UCG-001, Anaerovorax, Ruminococcus, Ruminobacter, Fibrobacter, Lachnospiraceae_AC2044_group and Clostridia_UCG-014 might have been involved in the BH process. In conclusion, the results suggest that the inclusion of PTs in the diet improved rumen fermentation and FA composition through modulating the rumen bacterial community.

Highlight • Coleus amboinicus Lour. (CAL) into sheep diet decreased CH4 emission. • CAL did not reduce nutrient digestibility, but inhibited the methanogen community. • CAL increased ruminal propionate proportion and decreased acetate/propionate ratio. • CAL elevated n-3 fatty acid concentration in ruminal fluid and meat. • Supplementation of CAL improved some meat quality traits. Graphical abstract

IntroductionMicrobial 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.Materials and methodsWe 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.Results and discussionMost 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.

Extruded flaxseed (25%) and ground hay (75%) were each fed (DM basis) either together in a total mixed ration (TMR) or as flaxseed first followed by hay (non-TMR) to three pens of eight crossbred steers (n = 24 per diet) for 240 days. Compared to TMR, feeding non-TMR enriched subcutaneous fat with α-linolenic acid (ALA, 18:3n-3) and its biohydrogenation intermediates including vaccenic acid [trans(t)11-18:1], rumenic acid [cis(c)9,t11-conjugated linoleic acid] and conjugated linolenic acid (CLnA). Rumen microbial analysis using QIIME indicated that 14 genera differed (P ≤ 0.05) between TMR and the non-TMR. Azoarcus and Streptococcus were the only genera which increased in relative abundance in the TMR fed steers, whereas Methanimicrococcus, Moryella, Prevotella, Succiniclasticum, Succinivibrio, Suttenella, and TG5 decreased as compared to steers fed the non-TMR. Among these, Moryella, Succiniclasticum, and Succinivibrio, spp. were correlated with fatty acid profiles, specifically intermediates believed to be components of the major biohydrogenation pathway for ALA (i.e., t11, c15-18:2, c9, t11, c15-18:3, and total CLnA). In addition, negative correlations were found between the less abundant Ruminoccocus-like OTU60 and major ALA biohydrogenation intermediates, as well as positive correlations with several intermediates from alternative pathways that did not involve the formation of trans 11 double bonds. The present results suggest a number of pathways for ALA biohydrogenation are operating concurrently in the rumen, with their balance being influenced by diet and driven by less abundant species rather than members of the core bacterial population.

ABSTRACT Isoprene is a ubiquitously distributed, biogenic, and climate-active organic compound. Microbial isoprene degradation in oxic environments is fairly well understood; however, studies exploring anaerobic isoprene metabolism remain scarce, with no isolates for study available. Here, we obtained an acetogenic isolate, designated Acetobacterium wieringae strain Y, which hydrogenated isoprene to a mixture of methyl-1-butenes at an overall rate of 288.8 ± 20.9 μM day−1 with concomitant acetate production at a rate of 478.4 ± 5.6 μM day−1. Physiological characterization demonstrated that isoprene was not utilized in a respiratory process; rather, isoprene promoted acetogenesis kinetically. Bioinformatic analysis and proteomics experiments revealed the expression of candidate ene-reductases responsible for isoprene biohydrogenation. Notably, the addition of isoprene to strain Y cultures stimulated the expression of proteins associated with the Wood-Ljungdahl pathway, indicating unresolved impacts of isoprene on carbon cycling and microbial ecology in anoxic environments (e.g., promoting CO2 plus H2 reductive acetogenesis while inhibiting methanogenesis). Our new findings advance understanding of microbial transformation of isoprene under anoxic conditions and suggest that anoxic environments are isoprene sinks. IMPORTANCE Isoprene is the most abundant, biologically generated, volatile organic compound on Earth, with estimated emissions in the same magnitude as methane. Nonetheless, a comprehensive knowledge of isoprene turnover in the environment is lacking, impacting global isoprene flux models and our understanding of the environmental fate and longevity of isoprene. A critical knowledge gap that has remained largely unexplored until recently is the microbiology and associated molecular mechanisms involved in the anaerobic biotransformation of isoprene. By integrating culture-dependent approaches with omics techniques, we isolated an acetogen, Acetobacterium wieringae strain Y, capable of anaerobic biohydrogenation of isoprene. We obtained the complete genome of strain Y, and proteomic experiments identified candidate ene-reductases for catalyzing the asymmetric reduction of the electronically activated carbon-carbon double bond of isoprene. We also demonstrated that isoprene biohydrogenation stimulates the expression of Wood-Ljungdahl pathway enzymes. This study emphasizes the ecological roles of specialized Acetobacterium on the natural cycling of isoprene in anoxic environments and the potential effects of isoprene biohydrogenation on acetogens and methanogens, which have implications for global climate change and bioenergy production.

There is growing interest in specialized metabolites for fortification strategies in feed and/or as an antioxidant, anti-inflammatory and antimicrobial alternative for the containment of disorders/pathologies that can also badly impact human nutrition. In this context, the improvement of the diet of ruminant species with polyphenols and the influence of these compounds on animal performance, biohydrogenation processes, methanogenesis, and quality and quantity of milk have been extensively investigated through in vitro and in vivo studies. Often conflicting results emerge from a review of the literature of recent years. However, the data suggest pursuing a deepening of the role of phenols and polyphenols in ruminant feeding, paying greater attention to the chemistry of the single compound or to that of the mixture of compounds more commonly used for investigative purposes. [ABSTRACT FROM AUTHOR]

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 50 g 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. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Fatty acids can be protected by changing their structure or form against microbial activity, and the different forms of fatty acids can modulate the ruminal biohydrogenation rate and contribute to the desired fatty acid profile in milk fat., Objectives: The study investigated the effects of perilla (Perilla frutescens) dietary supplementation in the diet in different technological forms (seed, oil and formaldehyde-treated oil) on milk, plasma and ruminal fatty acid composition, and milk quality in lactating goats., Methods: The four dietary treatments consisted of (1) no supplementation, basal diet (CON); (2) perilla supplementation as seed at 44.7 g/kg (consisting of 20 g/kg oil (PS)); (3) perilla supplementation as oil at 20 g/kg (PO); (4) perilla supplementation as formaldehyde treated oil at 20 g/kg (protected perilla oil [PPO]). The experiment was implemented in a double 4 × 4 Latin square trial design, and sampling was carried out for 7 days after 21 days of adaptation., Results: Performance parameters were not affected by P. frutescens supplementation to the diet. PO decreased milk fat, whereas PPO increased milk fat. Milk cholesterol was not affected by P. frutescens dietary supplementation. Perilla oil supplementation in different forms to the diet did not affect ruminal pH, VFA and methane production. Perilla oil supplementation in different forms to the diet did not also affect the concentration of blood serum glucose, cholesterol and non-esterified fatty acids. Perilla supplementation to the diet increased the milk conjugated linoleic acid (CLA), C18:3n-3, C22:5n-3, C20:5n-3, C22:6n-3 and polyunsaturated fatty acid (PUFA) concentrations, and PPO group showed the greatest values. Ruminal palmitic (C16:0) acid was decreased, and in perilla groups, stearic acid (C18:0) concentration had the lowest, and ruminal c-9, t-11 CLA concentration had the highest value in PPO., Conclusions: It has been found that the most effective form of perilla oil in increasing milk quality is that with formaldehyde treatment (protected form). Perilla oil, which is a rich source of omega 3 in the diet, can be used to increase milk quality in goats without adversely affecting performance, ruminal fermentation and blood parameters., (© 2024 The Author(s). Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Conjugated linoleic acid (CLA) has drawn significant attention in the last two decades for its various potent beneficial effects on human health, such as anticarcinogenic and antidiabetic properties. CLA could be generally found in ruminant products, such as milk. The amount of CLA in ruminant products mainly depends on the diet of the animals. In general, the fat content in the ruminant diet is low, and dietary fat supplementation can be provided to improve rumen activity and the fatty acid (FA) profile of meat and milk. Especially, dietary 18-carbon polyunsaturated FA (C18 PUFA), the dominant fat source for ruminants, can modify the milk FA profile and other components by regulating the ruminal microbial ecosystem. In particular, it can improve the CLA in milk, intensify the competition for metabolic hydrogen for propionate producing pathways and decrease methane formation in the rumen. Therefore, lipid supplementation appears to be a promising strategy to naturally increase the additional nutritional value of milk and contribute to lower methane emissions. Meanwhile, it is equally important to reveal the effects of dietary fat supplementation on rumen fermentation, biohydrogenation (BH) process, feed digestion, and microorganisms. Moreover, several bacterial species and strains have been considered to be affected by C18 PUFA or being involved in the process of lipolysis, BH, CLA, or methane emissions. However, no review so far has thoroughly summarized the effects of C18 PUFA supplementation on milk CLA concentration and methane emission from dairy cows and meanwhile taken into consideration the processes such as the microorganisms, digestibility, rumen fermentation, and BH of dairy cattle. Therefore, this review aims to provide an overview of existing knowledge of how dietary fat affects rumen microbiota and several metabolic processes, such as fermentation and BH, and therefore contributes to functional and low-carbon milk production.

Cysteamine (CS), as a feed supplement, can increase the level of growth hormone (GH) in the blood, promote animal growth. However, little attention has been paid to the effects of CS on the rumen microbiome and metabolic profile in cashmere goats. This study aimed to assess the effects of rumen microbiota, metabolites, and plasma antioxidative capacity induced by CS supplementation in cashmere goats. We selected 30 Inner Mongolia white cashmere goat ewes (aged 18 months), and randomly separate the goats into three groups (n = 10 per group) to experiment for 40 days. Oral 0 (control group, CON), 60 (low CS, LCS), or 120 mg/kg BW−1 (high CS, HCS) coated CS hydrochloride every day. Using 16S and internal transcribed spacer (ITS) rRNA gene amplicon sequencing, we identified 12 bacterial and 3 fungal genera with significant changes among the groups, respectively. We found a significant increase in rumen NH3-N and total volatile fatty acid (TVFA) concentrations in the LCS and HCS groups compared with the CON. With untargeted LC–MS/MS metabolomics, we screened 59 rumen differential metabolites. Among the screened metabolites, many unsaturated and saturated fatty acids increased and decreased with CS treatment, respectively. CS supplementation increased the levels of plasma total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), GH, and insulin-like growth factor-1(IGF-1). Spearman correlation analysis revealed that the abundance of U29-B03, Lactococcus, and Brochothrix were positively associated with the levels of δ2-THA, TVFA and antioxidant capacity. In conclusion, CS significantly affected rumen microbiota and fermentation parameters, and ultimately inhibited the biohydrogenation of rumen metabolites, enhanced plasma antioxidant capacity, and regulated some hormones of the GH–IGF-1 axis. This study provides an overall view into the CS application as a strategy to improve health production in cashmere goats.

Simple Summary: Conjugated linoleic acid (CLA) has been shown to have protective effects against various common diseases, such as obesity and cancer, improving human health. For several years, efforts have been made to increase CLA levels in milk by including sources of fats and oilseeds in the diets of lactating cows, causing a decrease in the amount of fat in the milk itself and a decrease in the yield of the products derived from it. A "safe" and economical way to increase CLA content without affecting fat content, is through grazing feeding since the content of CLA precursors (linoleic and α-linolenic acids) are present in greater quantity in pastures compared to feeding only balanced diets. The content of these precursors will depend on factors, such as age and nitrogen fertilization, since the high availability of nitrogen stimulates the synthesis of metabolic components, such as leaf protein. The bibliographic review shows how the inclusion of different forages and the agronomic management of pastures promote the improvement of CLA levels in milk, giving "an added value". Conjugated linoleic acid (CLA), has been shown to have protective effects against various diseases, such as obesity, arteriosclerosis, diabetes, chronic inflammatory diseases, and cancer. This fatty acid in ruminants results from two processes, biohydrogenation, which takes place in the rumen, and de novo synthesis, carried out in the mammary gland, and it has linoleic and α-linolenic acids as its precursors. The amounts of precursors in the diets of animals are related to the amounts of CLA in milk. In the literature review, it was found that the milk of cows fed fresh forage has a higher amount of CLA because they have a higher amount of linoleic acid and α-linolenic acid compared to other foods used in the diets of cows. The amount of CLA precursors in pastures can be increased through agronomic practices, such as nitrogen fertilization, and regrowth age. It is also a technique used to increase the amount of CLA in milk to obtain a greater benefit regarding its nutritional value. [ABSTRACT FROM AUTHOR]

Simple Summary: Most unsaturated fatty acids in the ruminant's diet are hydrogenated in their rumen so that the composition of the fatty acids entering the rumen and their output is significantly different. Therefore, minimizing the ruminal biohydrogenation process of unsaturated fatty acids is one of the most important issues for feed supplements manufacturers and animal nutritionists to increase the availability of these fatty acids in the intestine. In recent years, encapsulation has been used to preserve the active ingredient in livestock; it is a method used to control the release of feed additives during digestion. There is a clear need to find a more effective method by which unsaturated fatty acids present in fat supplements can be protected to bypass rumen environment and its biohydrogenation, without negative effect on digestive efficiency, and be available in lower digestive tracts. For these reasons, this study aims to evaluate the use of natural materials to encapsulate fats and their effect on in vitro fermentation and fatty acid biohydrogenation. The results indicated that the percentage of ruminal saturated fatty acids decreased by encapsulation of flaxseed oil with chitosan (14% and 7%). The percentage of oleic unsaturated fatty acid by encapsulating flaxseed oil with chitosan (14%) had a significant increase compared to the control treatment (p < 0.05). Encapsulation of flaxseed oil with chitosan (14%) reduced the unsaturated fatty acids of ruminal biohydrogenation. The aim of this study was to investigate the effect of using chitosan nanoparticles and calcium alginate in the encapsulation of flaxseed oil on the biohydrogenation of unsaturated fatty acids and in vitro fermentation. The experiments were performed in a completely randomized design with 7 treatments. The experimental treatments included: diets without oil additive (control), diet containing 7% flaxseed oil, diet containing 14% flaxseed oil, diet containing 7% oil encapsulated with 500 ppm chitosan nanocapsules, diet containing 14% flaxseed oil encapsulated with 1000 ppm chitosan nanocapsules, diet containing 7% of flaxseed oil encapsulated with 500 ppm of calcium alginate nanocapsules, diet containing 14% flaxseed oil encapsulated with 1000 ppm calcium alginate nanocapsules. The results showed that encapsulation of flaxseed oil with calcium alginate (14%) had a significant effect on gas production (p < 0.05). The treatment containing calcium alginate (14%) increased the digestibility of dry matter compared to the control treatment, but the treatments containing chitosan caused a significant reduction (p < 0.05). The results indicated that the percentage of ruminal saturated fatty acids decreased by encapsulation of flaxseed oil with chitosan (14% and 7%). The percentage of oleic unsaturated fatty acid by encapsulating flaxseed oil with chitosan (14%) had a significant increase compared to the control treatment (p < 0.05). As a result, encapsulating flaxseed oil with chitosan (14%) reduced the unsaturated fatty acids generated during ruminal biohydrogenation. [ABSTRACT FROM AUTHOR]

This review aims to give an overview of the efficacy of yeast supplementation on growth performance, rumen pH, rumen microbiota, and their relationship to meat and milk quality in ruminants. The practice of feeding high grain diets to ruminants in an effort to increase growth rate and weight gain usually results in excess deposition of saturated fatty acids in animal products and increased incidence of rumen acidosis. The supplementation of yeast at the right dose and viability level could counteract the acidotic effects of these high grain diets in the rumen and positively modify the fatty acid composition of animal products. Yeast exerts its actions by competing with lactate-producing (Streptococcus bovis and Lactobacillus) bacteria for available sugar and encouraging the growth of lactate-utilising bacteria (Megasphaera elsdenii). M. elsdenii is known to convert lactate into butyrate and propionate leading to a decrease in the accumulation of lactate thereby resulting in higher rumen pH. Interestingly, this creates a conducive environment for the proliferation of vaccenic acid-producing bacteria (Butyrivibrio fibrisolvens) and ciliate protozoa, both of which have been reported to increase the ruminal concentration of trans-11 and cis-9, trans-11-conjugated linoleic acid (CLA) at a pH range between 5.6 and 6.3. The addition of yeast into the diet of ruminants has also been reported to positively modify rumen biohydrogenation pathway to synthesise more of the beneficial biohydrogenation intermediates (trans-11 and cis-9, trans-11). This implies that more dietary sources of linoleic acid, linolenic acid, and oleic acid along with beneficial biohydrogenation intermediates (cis-9, trans-11-CLA, and trans-11) would escape complete biohydrogenation in the rumen to be absorbed into milk and meat. However, further studies are required to substantiate our claim. Therefore, techniques like transcriptomics should be employed to identify the mRNA transcript expression levels of genes like stearoyl-CoA desaturase, fatty acid synthase, and elongase of very long chain fatty acids 6 in the muscle. Different strains of yeast need to be tested at different doses and viability levels on the fatty acid profile of animal products as well as its vaccenic acid and rumenic acid composition.

Context: Dietary strategies may influence the fatty acid composition of sheep meat and ultimately its nutritional and sensory quality. Aim: This study investigated the effects of silage to concentrate ratio and feeding duration on the concentration of intramuscular fatty acids and branched chain fatty acid in subcutaneous adipose tissue of lambs. Methods: Pasture fed lambs were assigned in groups of 11 to one of nine dietary treatments consisting of silage to cereal concentrate at ratios (dry matter basis) of 100:0 (silage), 50:50 (silage:concentrate) or 0:100 (concentrate) for three feeding durations (36, 54 or 72 days) pre-slaughter. A 10th group of 11 lambs remained at pasture until slaughter. Fatty acid methyl esters were prepared using a microwave-assisted method and quantified by gas chromatography with flame ionisation detection. Results: The concentration of n -3 polyunsaturated fatty acids (PUFA) and proportions of C18:3 n -3 and C18:2 cis -9 trans -11 decreased for mixed feed and/or concentrate treatments, but not for silage, from 36 to 72 days. The C18:2 n -6 and n -6 PUFA concentrations increased for mixed feed and concentrate, but not for silage, from 36 to 72 days. The animals that remained at pasture had lower C18:2 n -6 and n -6 PUFA than those receiving mixed feed for 72 days, concentrate for 54 days and concentrate for 72 days, but higher C18:3 n -3, C18:2 cis -9 trans -11 and n -3 PUFA concentrations than the indoor finishing groups. The n -6/ n -3 PUFA ratio was lower in pastured lambs compared to the other groups. 4-Methyloctanoic acid and 4-ethyloctanoic acid were higher in concentrate and mixed feed treatments than in silage while 4-methylnonanoic acid increased with increase in concentrate level in the diet. Conclusion: The ratio of silage to concentrate in the diet and duration of feeding pre-slaughter influence the fatty acid composition of muscle and subcutaneous adipose tissue of lambs. Implications: The results are important for lamb producers in understanding the nutritional and sensory implications of altering lamb diets. The fatty acid profile of meat from lambs fed a pasture diet is affected by changing the diet before slaughter. The effect of pasture on meat fatty acids is partially conserved by feeding lambs on grass silage for up to 72 days, or cereal-containing diets for less than 36 days, before slaughter. Feeding cereal-containing diets to lambs for more than 54 days results in a meat fatty acid profile that reflects the composition of the cereal-containing diet. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the inclusion level of licuri cake (LC) in the diet of confined cows on fatty acid profile and milk cholesterol. Four cows with a blood level of ½ to ¾ Holstein x Zebu blood were used, distributed in a 4 x 4 Latin square, where the inclusion levels of the cake in the total diet were 0.0, 5.5, 11.0 and 16.5%, replacing soybean meal in the diet. There was a linear decreasing effect for the fatty acids Lauric, Elaidic, Gamma-Linolenic and conjugated linoleic acid isomers (C18:2cis9trans11; C18:2trans10cis12) from the inclusion levels of LC. The inclusion of licuri cake negatively influenced the concentrations of polyunsaturated fatty acids and conjugated linoleic acid isomers, in addition to the fatty acids of the Omega-6 series, which is not interesting from the human nutrition point of view.

The reuse of by-products from the agro-industry in animal feeding is desirable to increase the sustainability of the productions. Hazelnut skin is a by-product of the food industry and due to the high content in crude fat and phenolic compounds can be potentially used in ruminants’ diet. In this study, we characterised and compared the microbial communities of rumen digesta (RD) from lambs fed a diet supplied with hazelnut skin vs. a control diet. Microbial DNA was extracted and high-throughput sequencing of 16S rRNA gene amplicons was performed. Six genera ([Eubacterium] nodatum group, Acidaminococcus, Dialister, Erysipelotrichaceae UCG-002, Megasphaera, and Olsenella) showed a positive correlation with the concentration of C18:1 t10, and their relative abundance was higher in the RD from lambs fed the control diet, compared to the RD from lambs fed the diet supplied with hazelnut skin. The results suggest that the relative abundance of microorganisms correlated to C18:1 t10 production in the rumen of animals fed a concentrate-based diet can be reduced by the administration of hazelnut skin.Highlights A diet with hazelnut skin affected the microbial community in the rumen of lambs The relative abundance of the genus Dialister decreased with hazelnut skin Administration of hazelnut skin can be a strategy to reduce the C18:1 t10/t11 ratio

The rumen is characterised by a complex microbial ecosystem, which is particularly active in lipid metabolism. Several studies demonstrated a role of diet and breed on bacterial community profile, with the effect on metabolic pathways. Despite the knowledge achieved on metabolism and the bacterial profile, little is known about the relationship between individual bacteria and metabolic pathways. Therefore, a multivariate approach was used to search for possible relationships between bacteria and products of several pathways. The correlation between rumen bacterial community composition and rumen lipid metabolism was assessed in 40 beef steers (20 Maremmana and 20 Aubrac) reared with the same system and fed the same diet. A canonical discriminant analysis combined with a canonical correlation analysis (CCA) was performed to explore this correlation. The variables showing a Pearson correlation higher than 0.6 as absolute value and significant were retained for CCA considering the relationship of bacterial composition with several metabolic pathways. The results indicated that some bacterial genera could have significant impacts on the presence of several fatty acids. However, the relationship between genera and fatty acid changes according to the breed, demonstrating that the metabolic pathways change according to the host genetic background, related to breed evolution, although there is also an intra-breed genetic background which should not be ignored. In Maremmana, Succiniclasticum and Rikenellaceae_RC9_gut_group showed a high positive correlation with dimethylacetals (DMAs) DMAC13:0, DMAC14:0, DMAC14:0iso, DMAC15:0, DMAC15:0iso, and DMAC18:0. Prevotellaceae_UCG-003 correlates with C18:3c9c12c15 and C18:1t11, while Fibrobacter and Succiniclasticum correlate with C18:2c9t11 and Lachnospiraceae_NK3A20_group correlates with C18:1c12. Prevotellaceae_UCG-003, Ruminococcaceae_UCG-010, and Oribacterium showed a positive correlation with C13:0iso, and C17:0. Conversely, in Aubrac, Treponema_2 and Rikenellaceae_RC9_gut_group correlated with DMAC14:0iso, DMAC16:0iso, DMAC17:0iso, while Ruminococcaceae_UCG-010, Christensenellaceae_R-7_group and Ruminococcaceae_NK4A214_group correlated with DMAC18:1t11, DMAC14:0, DMAC18:1c12. Acetitomaculum correlated with C18:2c9c12, C18:1c12, C18:1c13, C18:1t12 and Lachnospiraceae_NK3A20_group with C18:1t6-8 and C18:1t9. Saccharofermentas, Ruminococcaceae_UCG-010 and Rikenellaceae_RC9_gut_group correlated with C18:2c9t11 while, Prevotellaceae_UCG-001 and Ruminococcus_1 correlated with C14:0iso, C15:0, C15:0iso, C17:0. Saccharofermentans, Rikenellaceae_RC9_gut_group, Ruminococcaceae_NK4A214_group, and Ruminococcaceae_UCG-010 correlated with C13:1c12 and C16:0iso. These results lead to hypothesise a possible association between several metabolic pathways and one or a few bacterial genera. If these associations are confirmed by further investigations that verify the causality of a bacterial genus with a particular metabolic process, it will be possible to deepen the knowledge on the activity of the rumen population in lipid metabolism. This approach appears to be a promising tool for uncovering the correlation between bacterial genera and products of rumen lipid metabolism.

Background: Methane production and fatty acids (FA) biohydrogenation in the rumen are two main constraints in ruminant production causing environmental burden and reducing food product quality. Rumen functions can be modulated by the biologically active compounds (BACs) of plant origins as shown in several studies e.g. reduction in methane emission, modulation of FA composition with positive impact on the ruminant products. Coleus amboinicus Lour. (CAL) contains high concentration of polyphenols that may potentially reduce methane production and modulate ruminal biohydrogenation of unsaturated FA. This study aimed to investigate the effect of BAC of Coleus amboinicus Lour. (CAL) fed to growing lambs on ruminal methane production, biohydrogenation of unsaturated FA and meat characteristics. In this study, the in vitro experiment aiming at determining the most effective CAL dose for in vivo experiments was followed by two in vivo experiments in rumen-cannulated rams and growing lambs. Experiment 1 (RUSITEC) comprised of control and three experimental diets differing in CAL content (10%, 15%, and 20% of the total diet). The two in vivo experiments were conducted on six growing, rumen-cannulated lambs (Exp. 2) and 16 growing lambs (Exp. 3). Animals were assigned into the control (CON) and experimental (20% of CAL) groups. Several parameters were examined in vitro (pH, ammonia and VFA concentrations, protozoa, methanogens and select bacteria populations) and in vivo (methane production, digestibility, ruminal microorganism populations, meat quality, fatty acids profiles in rumen fluid and meat, transcript expression of 5 genes in meat). Results: CAL lowered in vitro methane production by 51%. In the in vivo Exp. 3, CAL decreased methane production by 20% compared with the CON group, which corresponded to reduction of total methanogen counts by up to 28% in all experiments, notably Methanobacteriales. In Exp. 3, CAL increased or tended to increase populations of some rumen bacteria (Ruminococcus albus, Megasphaera elsdenii, Butyrivibrio proteoclasticus, and Butyrivibrio fibrisolvens). Dietary CAL suppressed the Holotricha population, but increased or tended to increase Entodiniomorpha population in vivo. An increase in the polyunsaturated fatty acid (PUFA) proportion in the rumen of lambs was noted in response to the CAL diet, which was mainly attributable to the increase in C18:3 cis-9 cis-12 cis-15 (LNA) proportion. CAL reduced the mRNA expression of four out of five genes investigated in meat (fatty acid synthase, stearoyl-CoA desaturase, lipoprotein lipase, and fatty acid desaturase 1). Conclusions: Summarizing, polyphenols of CAL origin (20% in diet) mitigated ruminal methane production by inhibiting the methanogen communities. CAL supplementation also improved ruminal environment by modulating ruminal bacteria involved in fermentation and biohydrogenation of FA. Besides, CAL elevated the LNA concentration, which improved meat quality through increased deposition of n-3 PUFA. Highlight: • Coleus amboinicus Lour. (CAL) into sheep diet decreased CH4 emission. • CAL did not reduce nutrient digestibility, but inhibited the methanogen community. • CAL increased ruminal propionate proportion and decreased acetate/propionate ratio. • CAL elevated n-3 fatty acid concentration in ruminal fluid and meat. • Supplementation of CAL improved some meat quality traits. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the carcass characteristics and fatty acid (FA) profile of the meat of Creole lambs supplemented with cottonseed (CS) and ground corn (GC). Twentyfour (24) males of 90 d and 16 ± 2 kg of initial weight were used. The lambs were assigned to four treatments, T0: grazing; T1: grazing + 25%-CS + 75%-GC; T2: grazing + 50%-CS + 50%-GC and T3: grazing + 75%-CS + 25%-GC, under a complete randomized design. After 127 d of supplementation, the animals were slaughtered, and the hot and cold carcass was weighed. Two hundred grams of the Longissimus dorsi muscle were taken to evaluate the proportion of FAs in each animal using gas chromatography. An analysis of variance was developed to determine the effect of diet. The supplemented animals had an average weight of 32.15 kg, being higher (P<0.05) than that registered by the lambs of the T0 (23.3 kg). Similarly, a higher average yield of the carcasses of lambs that received supplementation 48.2 vs 39.5 %) was observed. Palmitic and stearic FAs increased in the meat of supplemented animals (P≤0.05), especially in those fed the T2 diet. Supplementation with CS and GC positively altered (P≤0.05) the ratio of monounsaturated acids (MFAs) and polyunsaturated acids (PFAs). The treatments did not influence (P>0.05) the MFA:SFA ratio and the atherogenicity index. However, the diet affected (P<0.05) the desirable PFA:SFA and FA ratio. Supplementation with CS and GC positively influenced slaughter weight, carcass yield and fatty acid profile in lambs. [ABSTRACT FROM AUTHOR]

Objective The present investigation was aimed to explore the potential of lactobacilli for conjugated linoleic acid (CLA) production, isolated from rumen fluid samples of lactating goats. Methods A total of 64 isolates of lactobacilli were obtained using deMan-Rogosa-Sharpe (MRS) agar from rumen fluid of goats and further subjected to morphological and biochemical characterizations. Isolates found as gram-positive, catalase negative rods were presumptively identified as Lactobacillus species and further confirmed by genus specific polymerase chain reaction (PCR). The phylogenetic tree was constructed from the nucleotide sequences using MEGA6. Results Out of the 64 isolates, 23 isolates were observed positive for CLA production by linoleate isomerase gene-based amplification and quantitatively by UV-spectrophotometric assay for the conversion of linoleic acid to CLA as well as gas chromatography-based assay. In all Lactobacillus species cis9, trans11 isomer was observed as the most predominant CLA isomer. These positive isolates were identified by 16S rRNA gene-based PCR sequencing and identified to be different species of L. ingluviei (2), L.salivarius (2), L. curvatus (15), and L. sakei (4). Conclusion The findings of the present study concluded that lactic acid bacteria isolated from ruminal fluid samples of goat have the potential to produce bioactive CLA and may be applied as a direct fed microbial to enhance the nutraceutical value of animal food products.

Abstract Background Bacteria involved in ruminal formation of trans-10 intermediates are unclear. Therefore, this study aimed at identifying rumen bacteria that produce trans-10 intermediates from 18-carbon unsaturated fatty acids. Results Pure cultures of 28 rumen bacterial species were incubated individually in the presence of 40 μg/mL 18:3n-3, 18:2n-6 or trans-11 18:1 under control or lactate-enriched (200 mM Na lactate) conditions for 24 h. Of the 28 strains, Cutibacterium acnes (formerly Propionibacterium acnes) was the only bacterium found to produce trans-10 intermediates from 18:3n-3 and 18:2n-6, irrespective of the growth condition. To further assess the potential importance of this species in the trans-11 to trans-10 shift, different biomass ratios of Butyrivibrio fibrisolvens (as a trans-11 producer) and C. acnes were incubated in different growth media (control, low pH and 22:6n-3 enriched media) containing 40 μg/mL 18:2n-6. Under control conditions, a trans-10 shift, defined in the current study as trans-10/trans-11 ≥ 0.9, occurred when the biomass of C. acnes represented between 90 and 98% of the inoculum. A low pH or addition of 22:6n-3 inhibited cis-9, trans-11 CLA and trans-10, cis-12 CLA formation by B. fibrisolvens and C. acnes, respectively, whereby C. acnes seemed to be more tolerant. This resulted in a decreased biomass of C. acnes required at inoculation to induce a trans-10 shift to 50% (low pH) and 90% (22:6n-3 addition). Conclusions Among the bacterial species studied, C. acnes was the only bacterium that have the metabolic ability to produce trans-10 intermediates from 18:3n-3 and 18:2n-6. Nevertheless, this experiment revealed that it is unlikely that C. acnes is the only or predominant species involved in the trans-11 to trans-10 shift in vivo.

This research was aimed at studying the in vitro ruminal biohydrogenation (BH) of C18 fatty acids (FA) in mixtures of Indigofera zollingeriana and Brachiaria decumbens. Four combinations of experimental rations of I. zollingeriana : B. decumbens were tested i.e., IZ 1 (45%:45%), IZ 2 (60%:30%), IZ 3 (75%:15%), and IZ 4 (90%:0%). The remaining 10% in in each ration was rice bran. The experimental design was based on a completely randomized design with five replicates. Results revealed that there was a statistically significant difference (P0.05). Composition of C18:0 after incubation showed a significant difference (P

Aim: The aim of this study was to evaluate the effects of various combinations of tropical grass-legume species in rations on the biohydrogenation (BH) activity of unsaturated fatty acids (FAs), C18:0 composition, and fermentation profile in an in vitro rumen system. Materials and Methods: Samples of the following five fodder plants were used: One species of grass (Pennisetum purpureum) and four species of tree legumes (Leucaena leucocephala, Gliricidia sepium, Calliandra calothyrsus, and Indigofera zollingeriana). The following eight experimental diets were evaluated: 50% P. purpureum + 50% L. leucocephala (LL I); 50% P. purpureum + 50% G. sepium (GS I); 50% P. purpureum + 50% C. calothyrsus (CC I); 50% P. purpureum + 50% I. zollingeriana (IZ I); 75% P. purpureum + 25% L. leucocephala (LL II); 75% P. purpureum + 25% G. sepium (GS II); 75% P. purpureum + 25% C. calothyrsus (CC II); and 75% P. purpureum + 25% I. zollingeriana (IZ II). Each ration was replicated 3 times. In vitro rumen incubation was performed for 48 h, according to the Tilley and Terry method. Determination of the FA profiles of the forage materials and rumen fluid samples was performed using gas chromatography. Results: The percentage of polyunsaturated FA (PUFA) in the forage materials ranged from 34.18% (P. purpureum) to 74.51% (C. calothyrsus). The percentage of monounsaturated FA (MUFA) ranged from 5.06% (P. purpureum) to 8.71% (L. leucocephala). The percentage of saturated FA (SFA) was the lowest at 19.12% (C. calothyrsus) and highest at 60.76% (P. purpureum). In vitro BH of C18:3 n-3, C18:2 n-6, C18:1 n-9, and C18 PUFA in the experimental diets ranged from 72% to 100%. The BH of C18:1 n-9 in GS I (80%) and IZ I (72%) was significantly different (p0.05) were observed in the fermentation parameters (pH, total volatile FAs, in vitro dry matter digestibility, and in vitro organic matter digestibility) among the treatments, except in NH3 concentration (p

Sub-acute ruminal acidosis (SARA) is sometimes observed along with reduced milk fat synthesis. Inconsistent responses may be explained by dietary fat levels. Twelve ruminally cannulated cows were used in a Latin square design investigating the timing of metabolic and milk fat changes during Induction and Recovery from SARA by altering starch levels in low-fat diets. Treatments were (1) SARA Induction, (2) Recovery and (3) Control. Sub-acute ruminal acidosis was induced by feeding a diet containing 29.4% starch, 24.0% NDF and 2.8% fatty acids (FAs), whereas the Recovery and Control diets contained 19.9% starch, 31.0% NDF and 2.6% FA. Relative to Control, DM intake (DMI) and milk yield were higher in SARA from days 14 to 21 and from days 10 to 21, respectively (P < 0.05). Milk fat content was reduced from days 3 to 14 in SARA (P < 0.05) compared with Control, while greater protein and lactose contents were observed from days 14 to 21 and 3 to 21, respectively (P < 0.05). Milk fat yield was reduced by SARA on day 3 (P < 0.05), whereas both protein and lactose yields were higher on days 14 and 21 (P < 0.05). The ruminal acetate-to-propionate ratio was lower, and the concentrations of propionate and lactate were higher in the SARA treatment compared with Control on day 21 (P < 0.05). Plasma insulin increased during SARA, whereas plasma non-esterified fatty acids and milk β-hydroxybutyrate decreased (P < 0.05). Similarly to fat yield, the yield of milk preformed FA (>16C) was lower on day 3 (P < 0.05) and tended to be lower on day 7 in SARA cows (P < 0.10), whereas yield of de novo FA (