Search Results (299)

The use of exogenous enzymes in the nutrition of dairy cows is an innovative and efficient strategy to maximize productivity and milk quality, with positive applications in the economic and environmental aspects of dairy farming. Therefore, the objective of this study was to evaluate whether the addition of a blend of exogenous enzymes to the diet of lactating Jersey cows has a positive effect on productive performance, milk quality, animal health, ruminal environment, and digestibility. Twenty-one primiparous Jersey cows, with 210 days in lactation (DL), were used. The exogenous enzymes used were blends containing mainly protease, in addition to cellulase, xylanase, and beta-glucanase. The animals were divided into three groups with seven replicates per group (each animal being the experimental unit), as follows: Control (T-0), basal diet without enzyme addition; Treatment (T-80), animals fed enzymes in the diet at a daily dose of 80 mg per kg of dry matter (DM); Treatment (T-160), animals fed enzymes in the diet at a daily dose of 160 mg per kg of DM. The study lasted 84 days, during which higher milk production was observed in the treated groups (T-80 and T-160) compared to the control group (p = 0.04). When calculating feed efficiency from days 1 to 84, greater efficiency was observed in both groups that received the blend compared to the control (p = 0.05). In the centesimal composition of the milk, it was observed that the percentage of protein in the milk of the T-160 group was higher compared to the control group (p = 0.03). The effect of the enzymes was verified for butyric (p = 0.05) and palmitic (p = 0.05) fatty acids. We also observed the effect of the enzyme blend on the amount of volatile fatty acids (VFAs), which were higher in the ruminal fluid of cows that received the enzymes (p = 0.01). Cows that consumed enzymes showed a higher apparent digestibility coefficient of crude protein (p = 0.01). In vitro, the main result is related to lower gas production in 24 and 48 h at T-160. We concluded that the use of a blend of exogenous enzymes in the diet of lactating Jersey cows was able to increase milk production in these animals, resulting in greater feed efficiency and also an increase in milk protein content, positively modulating the fatty acid profile in the rumen and improving the apparent digestibility of nutrients. Full article

Direct-fed microbials (DFM) have emerged as a promising dietary strategy for enteric methane abatement. However, it is unclear whether in vitro studies trialing DFM should use ruminal fluid previously adapted to the DFM of interest or if the DFM can be directly added to an unadapted inoculum. Ten lactating, multiparous, rumen cannulated Holstein-Friesian cows were randomly allocated to one of two groups: 1) adapted, basal diet plus 4 g/d of a blend of Bacillus subtilis and Bacillus licheniformis (1.6 × 10⁹ CFU/g each), delivered via the rumen canula; and 2) naive, basal diet only. Ruminal fluid from both groups was incubated in an in vitro 24-h batch culture system with two rates of Bacillus spp. and three feed substrates (hay, pasture, cereal grain), resulting in 12 treatments. Methane production was 16% greater, and total volatile fatty acid concentration was 7% greater in incubations using adapted ruminal fluid compared to those using naive ruminal fluid; however, neither parameter was affected when Bacillus spp. was added to the batch incubation system. Future in vitro studies evaluating DFM should consider including a period of in vivo adaptation to mimic their potential impact under in vivo feeding conditions. Full article

Methane (CH₄), originating from ruminants, is a major source of greenhouse gas emissions in the agriculture industry. This study aimed to determine the potential of red seaweed Gracilaria lemaneiformis (G. lemaneiformis) as an anti-methanogenic feed additive for cattle. Three supplementation levels of seaweed (2%, 5%, and 10% of dry matter) were evaluated for their effects on gas production and rumen fermentation characteristics during 48 h in vitro fermentation. The results revealed a significant decrease in total gas production (TGP), CO₂, CH₄, ammonia nitrogen (NH₃-N), and volatile fatty acid (VFA) concentrations, with no differences in pH or dry matter disappearance (DMD). Notably, compared with the control group without seaweed, supplementation with 2% G. lemaneiformis effectively reduces CH₄ emissions by 27.5% (p < 0.05). Supplementation with 2% G. lemaneiformis decreased the abundance of methanogens g_norank_f_Methanomethylophilaceae, responsible for CH₄ generation, and increased the populations of bacteria (Kandleria and Succinivibrio) that compete with methanogens for substrates. Furthermore, upregulating the levels of 13(S)-HOTrE and 9(S)-HOTrE (polyunsaturated fatty acids) could inhibit methanogenic activity. Additionally, lower VFA concentrations will provide less raw materials for methane synthesis, thus further inhibiting methanogenesis. In summary, G. lemaneiformis, as a red seaweed with important economic value, can not only be applied to enhance marine carbon sinks but can also serve as a promising candidate for mitigating biomethane emissions in cattle. Full article

This study evaluated the effects of replacing soybean meal (SBM) with winged bean tuber (Psophocarpus tetragonolobus) fermented using ruminal Candida tropicalis KKU20 on gas kinetics, ruminal fermentation, and degradability using the in vitro gas production technique. A 3 × 4 factorial arrangement in a completely randomized design was used. Factor A included three roughage-to-concentrate (R:C) ratios: 60:40, 50:50, and 40:60. Factor B consisted of four levels of SBM replacement with yeast-fermented winged bean tuber (YFWBT): 0%, 33%, 66%, and 100%. Fermentation with C. tropicalis KKU20 increased the crude protein content of winged bean tuber by 13.32%. No significant interaction was found between the R:C ratio and YFWBT level for cumulative gas production at 24, 48, or 96 h (p > 0.05). Cumulative gas production at 96 h was not affected by either factor. However, at 24 and 48 h, gas production increased with higher proportions of concentrate (p < 0.05). Both the R:C ratio and YFWBT level significantly influenced pH and ammonia–nitrogen (NH₃-N) concentrations (p < 0.01). After 24 h, NH₃-N ranged from 7.66 to 13.76 mg/dL, rising to 16.44–16.63 mg/dL after 48 h. A significant interaction (p < 0.01) was observed for in vitro dry matter degradability (IVDMD) and in vitro organic matter degradability (IVOMD). Increasing concentrate levels along with YFWBT inclusion improved degradability at both incubation times. The highest IVDMD (64.49%) and IVOMD (65.81%) were recorded at 48 h in the 40:60 R:C ratio with 33% YFWBT. At 48 h, a significant interaction effect (p < 0.05) was also found for total volatile fatty acid (VFA) and propionic acid (C3) concentrations. Total VFA peaked in the 40:60 group with 33% YFWBT (104.31 mM), while the highest C3 concentration (26.22%) was observed in the same R:C group with 66% YFWBT. At 24 h, total VFA was significantly affected by the R:C ratio (p < 0.05), with the lowest values in the 60:40 group and increasing in response to higher concentrate and YFWBT levels. Incorporating YFWBT at 33% in diets with an R:C ratio of 40:60 optimized degradability, indicating its potential as a sustainable alternative to SBM in ruminant nutrition. Full article

Enhancing forage protein is key to sustainable ruminant nutrition. The nutritive value of Hedysarum coronarium L. was investigated by studying different preservation systems (fresh vs. dehydrated pellet vs. hay) (Exp. 1) and morphological fractions (flowers vs. leaves vs. stems) (Exp. 2). For the fresh and pelleted systems, two cuts were used. Proximately, total polyphenols and condensed tannins were detected. In vitro fermentation characteristics were studied by incubating samples with buffered sheep rumen fluid, estimating methane production by volatile fatty acids. Fresh and pelleted sulla were more nutritionally advantageous than hay, in terms of metabolizable energy and protein-to-fiber ratio. Pelleting at the beginning of flowering proved to be a suitable forage for sheep feeding due to protein (15.1% DM), metabolizable energy (9.64 MJ/kg DM), structural carbohydrates (39.5% DM), and total polyphenols (13.5 GAE g/kg DM) content. This cut showed an in vitro fermentation rate (9.86 mL/h), organic matter degradability (55.7%), and volatile fatty acids (87.3 mmoL/g) that were higher (p < 0.05) than hay. Flowers and leaves showed higher (p < 0.05) levels of secondary metabolites than stems as well as lower methane production. These results suggest the potential influence of these compounds in reducing rumen emissions. Dehydration and pelleting resulted in an effective preservation method for maintaining nutrients in sulla forage. Full article

This study evaluated the effects of liquid oregano oil, chitosan nanoparticles with encapsulated liquid oregano oil, and a negative control of empty chitosan nanoparticles on in vitro ruminal fermentation. Three Boer goats were used as ruminal fluid donors, fed with a formulated ration for 21 d for inoculum adaptation. Treatments tested on in vitro assays were diet without oregano oil or nanoparticles (CON); diet with 100 ppm of oregano oil in nanoparticles (100N); diet with 300 ppm of liquid oregano oil (300L); diet with 300 ppm of oregano oil in nanoparticles (300N); and diet with 300 ppm of empty nanoparticles (300CHN). The variables studied were in vitro dry matter digestibility (ivDMD), in vitro neutral detergent fiber digestibility (ivNDFD_om), total gas production (TGP), ammonia nitrogen concentration (NH₃), and pH. The experimental design was a randomized complete block design. Linear and quadratic regressions were used to identify dependence and inflection points. The ivDMD increased at 12, 36, and 48 h, with 300N and with 300L exhibiting increased ivNDFD_om at 36 h. Ruminal pH was highest (p < 0.05) with 300CHN at 36 h. For first-order regression analysis of TGP, coefficients (β) were highest (p < 0.05) for 300N. In conclusion, 300N increased ruminal fermentation in vitro, as reflected by increases in ivDMD, ivNDFD_om, and TGP. Full article

Feed supplementation strategies are essential for optimizing cattle productivity, and the incorporation of non-conventional feed resources may reduce both production costs and environmental impact. This study evaluated the effects of pelletized protein concentrates (including Acacia farnesiana, A. schaffneri, and Agave duranguensis bagasse) on rumen fermentation parameters, microbial communities, and gas emissions. Fistulated bullocks received the concentrate daily, and ruminal contents were collected and filtered before and after supplementation to assess in vitro gas and methane production, pH, and microbial composition using high-throughput sequencing of 16S rRNA and mcrA amplicons. In addition, in situ degradability was evaluated during and after the supplementation period. Supplementation led to a significant (p < 0.05) reduction in degradability parameters and methane production, along with a marked decrease in the abundance of Methanobrevibacter and an increase in succinate-producing taxa. These effects were attributed to the enhanced levels of non-fiber carbohydrates, hemicellulose, crude protein, and the presence of bioactive secondary metabolites and methanol. Rumen microbiota composition was consistent with previously described core communities, and mcrA-based sequencing proved to be a valuable tool for targeted methanogen detection. Overall, the inclusion of non-conventional ingredients in protein concentrates may improve ruminal fermentation efficiency and contribute to methane mitigation in ruminants, although further in vivo trials on a larger scale are recommended. Full article

This study aimed to evaluate the effect of including silage from devilfish waste (SF-Hypostomus plecostomus) and probiotics (PB-Pediococcus acidilactici BX-B122 and Bacillus coagulans BX-B118) in ruminants on greenhouse gas production. The diets evaluated contained 0, 8, 14 and 20% of silage made from SF and the addition of PB at a dose of 0.2 mL/g of diet, using steers and sheep (rams) as rumen inoculum donors in a completely randomized statistical design with a 2 × 4 × 2 factorial arrangement. Asymptotic gas production (GP) was influenced (p < 0.01) by the interactions between rumen liquor (RL), SF, and PB. The inclusion of SF and PB resulted in a higher (p < 0.01) GP rate in sheep; however, the values were reduced with increasing levels of SF. Asymptotic CH₄ in the rumen fluid of steers decreased with an increasing SF percentage up to 14%. Probiotics had different effects on the rumen fluid of sheep and steers. In steers, probiotics substantially reduced (p < 0.01) CH₄ synthesis while supplementation increased it in sheep rumen fluid. Similarly, diets with probiotics had higher CO formation (p < 0.05) in sheep and steer liquor. Similarly, CO decreased (p < 0.05) with increasing levels of SF. In the rumen fluid of sheep and steers, the probiotics were found to reduce H₂S, while there was an SF-dose-dependent decrease in H₂S concentration. The ruminal pH and dry matter digestibility of sheep were higher than in steers. It can be concluded that increasing SF levels generally reduced the total gas and CH₄ production, with probiotics further enhancing this reduction, especially in CH₄ per unit of gas. Full article

Ruminant livestock contribute significantly to methane emissions, necessitating sustainable mitigation strategies. Essential oils (EOs) show promise for modulating ruminal fermentation, but their synergistic effects remain underexplored. Two 24 h in vitro experiments evaluated the synergistic effects of EO blends on rumen microbial fermentation. Exp. 1 screened five oils using two triad combinations. Triad 1 tested 10 combinations of thyme (THY), peppermint (PPM), and cinnamon leaf (CIN) oils. Triad 2 tested 10 combinations of anise (ANI), clove leaf (CLO), and peppermint (PPM) oils. Each blend was tested at 400 mg/L, using batch culture methods measuring: pH, ammonia-N (NH₃-N), and volatile fatty acids (VFAs). The two most effective blends, designated as T1 and T2, were selected for Exp. 2 to assess total gas and methane (CH₄) production using pressure transducer methods. All treatments were incubated in a rumen fluid–buffer mix with a 50:50 forage-to-concentrate substrate (pH 6.6). In Exp. 1, data were analyzed according to the Simplex Centroid Design using R-Studio. In Exp. 2, an analysis was conducted using the MIXED procedure in SAS. Mean comparisons were assessed through Tukey’s test. The results from Exp. 1 identified CIN+PPM (80:20) and ANI+CLO (80:20) as optimal combinations, both increasing total VFAs while reducing acetate/propionate ratios and NH₃-N concentrations. In Exp. 2, both combinations significantly reduced total gas and CH₄ productions compared to the control, with CIN+PPM achieving the greatest methane reduction (similar to monensin, the positive control). Specific essential oil combinations demonstrated synergistic effects in modulating rumen fermentation and reducing methane emissions, offering potential for sustainable livestock production. Further in vivo validation is required to optimize dosing and assess long-term effects on animal performance. Full article

Modified nano-clays, alone or combined with probiotics, may offer a novel and sustainable approach to improve ruminal fermentation and mitigate CH₄ emissions in high-fiber diets. This study evaluated the properties and effects of modified nano-bentonite (MNB), with or without yeast (Saccharomyces cerevisiae), compared to natural bentonite (NB) and monensin, using the in vitro gas production (GP) technique. The substrate used was a basal diet composed primarily of forage (Trifolium alexandrinum clover) in a 70:30 forage-to-concentrate ratio. The treatments were a control group receiving the basal diet without additives; a monensin-added diet containing 40 mg/kg of dry matter (DM); a yeast-added diet with Saccharomyces cerevisiae at 2 × 10⁸ CFU/g of DM; a NB clay-added diet at 5 g/kg of DM; and MNB diets added at two levels (0.5 g/kg of DM (MNB_Low) and 1 g/kg of DM (MNB_High)), with or without S. cerevisiae. MNB showed a smaller particle size and improved properties, such as higher conductivity, surface area, and cation exchange capacity, than NB. Sulfur and related functional groups were detected only in MNB. No differences were observed in total GP, while both the monensin diet and the MNB_High-with-yeast diet significantly reduced CH₄ emissions compared to the control (p < 0.05). The MNB_High-without-yeast combination significantly (p < 0.05) reduced hemicellulose degradation, as well as total protozoal counts, including Isotricha and Epidinium spp. (p < 0.05), compared to the control. Ammonia levels did not differ significantly among treatments, while NB and MNB_High diets tended to have (p = 0.063) the highest short-chain fatty acid (SCFA) concentrations. These findings suggest the potential modulatory effects of yeast and MNB on rumen fermentation dynamics and CH₄ mitigation. Full article

We quantified the bioactive compounds of Ethiopian coffee (ETH), spent coffee grounds SCGs from ETH (SCG-ETH), and mixed SCGs (SCG-MIX) prepared by filtration methods and investigated the effect of SCG-ETH on ruminal fermentation as well as the anthelmintic activity of ETH. Three substrates, meadow hay (MH)-barley grain (MH-BG), MH-SCG-ETH, and BG-SCG-ETH (1:1 w/w), were fermented using an in vitro gas production technique. The bioactive compounds were quantitatively analyzed using ultra-high-resolution mass spectrometry. We performed an in vitro larval development test to determine the anthelmintic effect of an aqueous extract of ETH against the gastrointestinal nematode (GIN) Haemonchus contortus. The total content of bioactive compounds was highest in SCG-ETH, followed by SCG-MIX and ETH (35.2, 31.2, and 20.9 mg/g dry matter, respectively). Total gas and methane production (p < 0.001) were decreased by both MH-SCG-ETH and BG-SCG-ETH. The in vitro digestibility of dry matter was higher for MH-SCG-ETH and BG-SCG-ETH than for MH-BG. The aqueous ETH extract exhibited a strong larvicidal effect, with a mean lethal dose of 13.2 mg/mL for 50% mortality and 31.9 mg/L for 99% mortality. SCG substrates have the potential to modulate ruminal fermentation and serve as a source of anthelmintic bioactive compounds against GINs in ruminants. Full article

Pelagic sargassum arriving in the Mexican Caribbean is a mixture of brown macroalgae containing polysaccharides, minerals, and secondary metabolites with potential in ruminant diets. The objective of the present study was to evaluate the effect of the inclusion of sargassum in integral diets (ID) on in vitro fermentation characteristics. A completely randomized design was used. The treatments were different levels of sargassum (ICD: 0%, ID10: 10%, ID20: 20% and ID30: 30%) added to a basal substrate (a mixture of Pennisetum purpureum Vc. CT-115 hay, corn, soybean, and molasses). Rumen fluid was obtained from five male lambs with a body weight of 40 ± 3 kg. In vitro gas production (IVGP) as well as dry matter degradability (DMD) and organic matter degradability (DOM) increased linearly (p < 0.0001) as the proportion of sargassum increased at 24, 48, and 72 h. Rumen fluid pH decreased (p < 0.05) with 30% inclusion at 48 h, while protozoan concentration was similar (p > 0.05) in all treatments with respect to the control at all evaluation times. These results indicate that the inclusion of pelagic sargassum in integral concentrated diets improves fermentative parameters, and its inclusion in diets for ruminants is feasible. This opens up a window of opportunity for its study as a novel additive or unconventional supplement. However, in vivo studies are necessary to rule out harmful effects on animal health and performance. Full article

The objective of this study was to assess the effects of gallic acid (GA) on nutrient degradability, gas production, rumen fermentation, and the microbial community and its functions using in vitro fermentation methods. An in vitro experiment was conducted to test GA dose levels (0, 5, 10, 20, and 40 mg/g DM) in the cow’s diet. Based on the results of nutrient degradability, gas production, and rumen fermentation, the control group (0 mg/g DM, CON) and the GA group (10 mg/g DM, GA) were selected for metagenomic analysis to further explore the microbial community and its functions. The degradability of dry matter and crude protein, as well as total gas production, CH₄ production, CH₄/total gas, CO₂ production, and CO₂/total gas, decreased quadratically (p < 0.05) with increasing GA doses, reaching their lowest levels at the 10 mg/g DM dose. Total volatile fatty acid (VFA) (p = 0.004), acetate (p = 0.03), and valerate (p = 0.03) exhibited quadratic decreases, while butyrate (p = 0.0006) showed a quadratic increase with increasing GA doses. The 10 mg/g DM dose group had the lowest levels of total VFA, acetate, and valerate, and the highest butyrate level compared to the other groups. The propionate (p = 0.03) and acetate-to-propionate ratio (p = 0.03) linearly decreased with increasing gallic acid inclusion. At the bacterial species level, GA supplementation significantly affected (p < 0.05) a total of 38 bacterial species. Among these, 29 species, such as Prevotellasp.E15-22, bacteriumP3, and Alistipessp.CAG:435, were less abundant in the GA group, while 9 species, including Aristaeella_lactis and Aristaeella_hokkaidonensis, were significantly more abundant in the GA group. At the archaeal species level, the relative abundances of Methanobrevibacter_thaueri, Methanobrevibacter_boviskoreani, and Methanobrevibactersp.AbM4 were significantly reduced (p < 0.05) by GA supplementation. Amino sugar and nucleotide sugar metabolism, Starch and sucrose metabolism, Glycolysis/Gluconeogenesis, and Pyruvate metabolismwere significantly enriched in the GA group (p < 0.05). Additionally, Alanine, aspartate and glutamate metabolism was also significantly enriched in the GA group (p < 0.05). GA use could potentially be an effective strategy for methane mitigation; however, further research is needed to assess its in vivo effects in dairy cows over a longer period. Full article

This study evaluated the effects of feedstuffs and additives in dairy cow rations on rumen methane production and nitrate content in groundwater. Two basal rations and their supplements were analyzed in regard to proximate parameters, and an in vitro rumen fermentation system assessed methane release and nitrate levels over 72 h. Supplementing dairy cow rations with Brassica rapa (BR) boosted the ether extract content, while silage produced the highest amount of methane. Rapidly degrading substrates like BR and ground maize produced methane faster, but in smaller amounts, than straw and silage. BR, Opuntia ficus-indica (OFI), and Posidonia oceanica (PO)-supplemented rations had mixed effects; PO reduced the methane yield, while OFI increased methane production rates. BR-supplemented rations had the lowest nitrate levels, making it suitable for anaerobic digestion. The multivariate analysis showed strong correlations between crude protein, dry matter, and ash, while high-nitrate substrates inhibited methane production, supporting the literature on the role of nitrates in reducing methanogenesis. These results emphasize the need to balance nutrient composition and methane mitigation strategies in dairy cow ration formulations. Full article

In vitro methods have advanced research on rumen microbiology and fermentation. However, artificial saliva formulation may need adjustments, particularly in urea content, for modern diets, warranting further research. This study investigated the effects of different nitrogen (N) levels in artificial saliva on ruminal fermentation and digestion in diets for dairy cows using a Rusitec^® system. Eighteen fermenters tested three saliva treatments with different N levels: a standard saliva as the control and two treatments with N reduced by 15% and 30%. Data were analyzed as a completely randomized design using the MIXED procedure of SAS (v. 9.4), with linear and quadratic contrasts tested for treatment effects (significance set at p ≤ 0.05). Results showed that altering N content had no significant effect on pH, ammonia concentrations, or NH₃-N outflow, nutrient digestibility (dry matter, crude protein, fiber, and starch), gas and methane production, or volatile fatty acid concentrations. The efficiency of microbial protein synthesis and N flow exhibited quadratic responses, with the lowest values observed at the highest level of N reduction in the saliva (−30%). These findings suggest that although ruminal function and digestion remain stable with reduced N, microbial protein synthesis efficiency may decline beyond a threshold. Full article