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Animals : An Open Access Journal From... Jun 2024Essential oils (EOs), as rumen additives, decreased CH emissions in in vitro trials but results from in vivo studies are still limited. We investigated the effects of...
Essential oils (EOs), as rumen additives, decreased CH emissions in in vitro trials but results from in vivo studies are still limited. We investigated the effects of (OEO) and (TEO) EOs on in vivo methane emissions from Nellore beef cattle. Six adult rumen-cannulated Nellore cattle were used in a double 3 × 3 Latin square design. Treatments consisted of three diets containing either 3 mL OEO per kg of concentrate, 3 mL TEO/kg of concentrate, or no EO addition. The experimental period consisted of three 21 d feeding periods and methane production was measured using the sulfur hexafluoride (SF6) technique from Day 16 to Day 21 of each feeding period. Intake, total apparent digestibility (dry matter as well as neutral and acid detergent fiber), and rumen parameters (pH, ammoniacal nitrogen concentration, and short-chain fatty acids) were also evaluated. The EOs did not decrease CH emissions and had no effect on rumen parameters.
PubMed: 38891711
DOI: 10.3390/ani14111664 -
Animals : An Open Access Journal From... May 2024The exploration of natural alternatives to antibiotics for enhancing productivity and performance in dairy cows is a crucial objective in farm animal management. This is...
The exploration of natural alternatives to antibiotics for enhancing productivity and performance in dairy cows is a crucial objective in farm animal management. This is the first study aimed at developing and evaluating the physicochemical properties and effects of Arabic gum-nano montmorillonite (AGNM) compost compared to ionophore monensin as feed additives on rumen fermentation, blood metabolites, and milk production of Holstein dairy cows. In a replicated 4 × 4 Latin square design, four multiparous mid-lactation Holstein dairy cows with an average body weight of 520 ± 15 kg were enrolled. The dietary treatments included a control diet (basal diet without feed additives), monensin diet [a basal diet supplemented with 35 mg/kg dry matter (DM) monensin], and AGNM diets comprising basal diet supplemented with two levels: low (L-AGNM) at 1.5 g/kg DM, and high (H-AGNM) at 3 g/kg DM. AGNM as a feed additive demonstrated promising physiochemical parameters, including containing highly bioactive components (α-amyrin and lupeol), functional groups (OH and Si-O), and essential mineral contents (Mg). Supplementations with H-AGNM significantly improved ruminal ( = 0.031) concentrations of total volatile fatty acids (VFAs), acetic ( = 0.05) and butyric ( = 0.05), enhanced ( < 0.05) digestibility of fiber and organic matter, while decreased ( = 0.013) estimated methane production. However, an increase ( = 0.04) in blood high-density lipoprotein levels and decrease ( < 0.05) in concentrations of creatinine (CREA), bilirubin (BILT), cholesterol (CHOL), and sodium (Na) were observed with H-AGNM supplementation. Both monensin and H-AGNM improved ( = 0.008) feed efficiency compared to L-AGNM; however, neither AGNM nor monensin affected the milk composition or energy status indicators of the dairy cows. The findings of this study highlight the potential of AGNM as a natural candidate to replace monensin in enhancing ruminal VFA production, nutrient digestibility, feed efficiency, blood metabolites, and milk yield in dairy cows.
PubMed: 38891693
DOI: 10.3390/ani14111649 -
Animals : An Open Access Journal From... May 2024The objective of this study was to evaluate the effects of the inclusion of dried (SO) shrub leaves on nutrient degradability, ruminal in vitro fermentation, gas...
The objective of this study was to evaluate the effects of the inclusion of dried (SO) shrub leaves on nutrient degradability, ruminal in vitro fermentation, gas production (GP), methane (CH), and carbon dioxide (CO) productions. Dried and ground SO shrub leaves were included at 0% (control), 0.5%, 1%, 1.5%, and 2% DM of a diet consisting of (per kg DM) 500 g concentrate feed mixture, 400 g berseem hay, and 100 g rice straw. The diet was incubated for 48 h. The asymptotic GP and the rate of GP changed linearly and quadratically ( < 0.01), with the highest GP observed at 1% inclusion of SO and then decreasing thereafter with greater inclusion (i.e., 1.5% and 2%), while CH production and its rate decreased linearly ( < 0.01) with all levels of SO inclusion. A linear increase in CO production and its rate was also found with an increasing level of SO inclusion in the diet ( < 0.05). Furthermore, the degradability of DM, NDF, and the concentration of total short-chain fatty acids and acetate changed linearly and quadratically, with the greatest being found at 1% SO inclusion and then steadily declining after ( < 0.01) with the 1.5% and 2% inclusion levels. Meanwhile, the propionate, NH-N, and microbial crude protein levels showed similar trends, with the plateau found at 1% inclusion of SO, where there was no change in butyrate concentration. Moreover, the pH, metabolizable energy, and partitioning factor (PF) also changed linearly and quadratically ( < 0.05), where the pH and PF were considerably reduced and ME increased with a 1% inclusion of SO ( < 0.05). In summary, SO at 1% inclusion in the diet showed the potential to improve gas production kinetics, nutrient degradability, and the ruminal fermentation profile, with a more significant reduction in ruminal CH production suggesting that SO at 1% could be included in the ruminant diet to reduce their carbon footprint and increase the production performance.
PubMed: 38891692
DOI: 10.3390/ani14111648 -
Animals : An Open Access Journal From... May 2024The dairy industry contributes significantly to anthropogenic methane emissions, which have an impact on global warming. This study aimed to investigate the effects of a...
The dairy industry contributes significantly to anthropogenic methane emissions, which have an impact on global warming. This study aimed to investigate the effects of a dietary inclusion of brown seaweed on enteric methane emissions (EMEs), hematological and blood biochemical profiles, and milk composition in dairy cows. Eighteen Holstein cows were divided into three groups: CON (non-supplemented cows), BS (50 mL of 10% ), and BS (100 mL of 10% ). In each cow, measurements of EME, dry matter intake (DMI), and milk yield (MY), as well as blood and milk sampling with respective analyzes, were performed before supplementation (P1), after 15 (P2) days, and after 30 (P3) days of supplementation. reduced ( < 0.05) methane production, methane yield, and methane intensity in both BS and BS, and raised DMI ( < 0.05) only in BS. Total bilirubin ( < 0.05) was higher in BS compared to CON cows in P2, and triacylglycerols were lower ( < 0.05) in BS than in CON cows in P3. Higher milk fat content was found in BS than in CON cows in P3. C16:0 proportions were higher ( < 0.05) in BS and BS than in CON cows, while C18:3n-3 was higher ( < 0.05) in BS than in BS and CON cows in P3. Dietary treatment with reduced EMEs and showed the potential to increase DMI and to improve energy status as well as milk composition in peak-lactating dairy cows.
PubMed: 38891568
DOI: 10.3390/ani14111520 -
Plants (Basel, Switzerland) May 2024The ratoon rice cropping pattern is an alternative to the double-season rice cropping pattern in central China due to its comparable annual yield and relatively lower...
The ratoon rice cropping pattern is an alternative to the double-season rice cropping pattern in central China due to its comparable annual yield and relatively lower cost and labor requirements. However, the impact of the ratoon rice cropping pattern on greenhouse gas (GHG) emissions and yields in the double-season rice region requires further investigation. Here, we compared two cropping patterns, fallow-double season rice (DR) and fallow-ratoon rice (RR), by using two early-season rice varieties (ZJZ17, LY287) and two late-season rice varieties (WY103, TY390) for DR, and two ratoon rice varieties (YLY911, LY6326) for RR. The six varieties constituted four treatments, including DR1 (ZJZ17 + WY103), DR2 (LY287 + TY390), RR1 (YLY911), and RR2 (LY6326). The experimental results showed that conversion from DR to RR cropping pattern significantly altered the GHG emissions, global warming potential (GWP), and GWP per unit yield (yield-scaled GWP). Compared with DR, the RR cropping pattern significantly increased cumulative methane (CH), nitrous oxide (NO), and carbon dioxide (CO) emissions by 65.73%, 30.56%, and 47.13%, respectively, in the first cropping season. Conversely, in the second cropping season, the RR cropping pattern effectively reduced cumulative CH, NO, and CO emissions by 79.86%, 27.18%, and 30.31%, respectively. RR led to significantly lower annual cumulative CH emissions, but no significant difference in cumulative annual NO and CO emissions compared with DR. In total, the RR cropping pattern reduced the annual GWP by 7.38% and the annual yield-scaled GWP by 2.48% when compared to the DR cropping pattern. Rice variety also showed certain effects on the yields and GHG emissions in different RR cropping patterns. Compared with RR1, RR2 significantly increased annual yield while decreasing annual GWP and annual yield-scaled GWP. In conclusion, the LY6326 RR cropping pattern may be a highly promising strategy to simultaneously reduce GWP and maintain high grain yield in double-season rice regions in central China.
PubMed: 38891339
DOI: 10.3390/plants13111527 -
Microbial Biotechnology Jun 2024Alkanes, single carbon methane to long-chain hydrocarbons (e.g. hexadecane and tetradecane), are important carbon sources to anaerobic microbial communities. In anoxic... (Review)
Review
Alkanes, single carbon methane to long-chain hydrocarbons (e.g. hexadecane and tetradecane), are important carbon sources to anaerobic microbial communities. In anoxic environments, archaea are known to utilize and produce methane via the methyl-coenzyme M reductase enzyme (MCR). Recent explorations of new environments, like deep sea sediments, that have coupled metagenomics and cultivation experiments revealed divergent MCRs, also referred to as alkyl-coenzyme M reductases (ACRs) in archaea, with similar mechanisms as the C utilizing canonical MCR mechanism. These ACR enzymes have been shown to activate other alkanes such as ethane, propane and butane for subsequent degradation. The reversibility of canonical MCRs suggests that these non-methane-activating homologues (ACRs) might have similar reversibility, perhaps mediated by undiscovered lineages that produce alkanes under certain conditions. The discovery of these alternative alkane utilization pathways holds significant promise for a breadth of potential biotechnological applications in bioremediation, energy production and climate change mitigation.
Topics: Anaerobiosis; Archaea; Methane; Hydrocarbons; Oxidoreductases; Alkanes; Metabolic Networks and Pathways; Biodegradation, Environmental
PubMed: 38888492
DOI: 10.1111/1751-7915.14508 -
Frontiers in Microbiology 2024Ruminal methane production is the main sink for metabolic hydrogen generated during rumen fermentation, and is a major contributor to greenhouse gas (GHG) emission....
Ruminal methane production is the main sink for metabolic hydrogen generated during rumen fermentation, and is a major contributor to greenhouse gas (GHG) emission. Individual ruminants exhibit varying methane production efficiency; therefore, understanding the microbial characteristics of low-methane-emitting animals could offer opportunities for mitigating enteric methane. Here, we investigated the association between rumen fermentation and rumen microbiota, focusing on methane production, and elucidated the physiological characteristics of bacteria found in low methane-producing cows. Thirteen Holstein cows in the late lactation stage were fed a corn silage-based total mixed ration (TMR), and feed digestion, milk production, rumen fermentation products, methane production, and rumen microbial composition were examined. Cows were classified into two ruminal fermentation groups using Principal component analysis: low and high methane-producing cows (36.9 vs. 43.2 L/DMI digested) with different ruminal short chain fatty acid ratio [(C2+C4)/C3] (3.54 vs. 5.03) and dry matter (DM) digestibility (67.7% vs. 65.3%). However, there were no significant differences in dry matter intake (DMI) and milk production between both groups. Additionally, there were differences in the abundance of OTUs assigned to uncultured sp., , and other 12 bacterial phylotypes between both groups. Specifically, a previously uncultured novel sp. with lactate-producing phenotype was detected, with higher abundance in low methane-producing cows. These findings provide evidence that may be associated with low methane and high propionate production. However, further research is required to improve the understanding of microbial relationships and metabolic processes involved in the mitigation of enteric methane.
PubMed: 38887715
DOI: 10.3389/fmicb.2024.1404991 -
Chemosphere Jun 2024Anaerobic co-digestion (AcoD) of food waste (FW) and landfill leachate has shown promising results in enhancing the methane yield. However, leachate includes toxic and...
Anaerobic co-digestion (AcoD) of food waste (FW) and landfill leachate has shown promising results in enhancing the methane yield. However, leachate includes toxic and refractory compounds that may impact the decomposition process. In this research, co-digested leachate was pretreated using ultrasonication and alkalinization to manipulate its characteristics toward improved synergism with FW. Experimental optimization was conducted through biochemical methane potential (BMP) assays to identify the optimum operating conditions of the pretreatment methods. The study evaluated the synergistic effects of co-digestion with raw and pretreated leachate on enhancing the performance in terms of feedstock solubilization and methane production. The BMP test demonstrated that alkalinization and ultrasonication improved the total methane generation by 35% and 27%, respectively, yielding around 397 and 375 mL CH per g of volatile solids. Moreover, ultrasonication and alkalinization enhanced the synergistic effects by 28% and 36%, respectively, compared to co-digestion with untreated leachate. Optimization by response surface methodology revealed that maximum performance could be achieved with leachate sonication at 212 W for 37.5 min or augmenting 788 g NaOH per kg of volatile solids. Kinetic and statistical models were derived to simulate and assess the impacts of the pretreatment parameters on the AcoD process. The results indicated that the ultrasonication energy had a higher influence on total solubility and methane production than alkaline dosage. Additionally, energy efficiency analyses were performed to examine the overall viability of the examined management approach and found that alkalinization increased the net energy efficiency by 23%, whereas ultrasonication was inefficient within the examined laboratory conditions despite the improved performance. The findings support an integrated organic waste management system where separated FW is co-treated with landfill leachate.
PubMed: 38885770
DOI: 10.1016/j.chemosphere.2024.142634 -
ACS Omega Jun 2024During the development of deep coalbed methane (CBM), the production of coal fines is common and suppresses the yield of CBM. This work takes the deep CBM wells in the...
During the development of deep coalbed methane (CBM), the production of coal fines is common and suppresses the yield of CBM. This work takes the deep CBM wells in the Qinshui Basin as a case study, and the output, composition, morphology, and sources of coal fines were investigated through scanning electron microscopy, X-ray diffraction, proximate analysis, and particle size measurement including image analysis, laser diffraction, and dynamic light scattering. The results indicate that, in comparison with shallow CBM wells, deep wells produce a greater quantity of coal fines which are darker in color and have smaller particle sizes, with the majority being less than 10 μm. The coal fines exist predominantly as aggregates that contained the iron-bearing and clay minerals. Based on the Liddinger particle settling model, the water production volume required for the coal fines to return to the surface in the Wuxiang block was calculated to be 8.55 m/d. This work can provide a scientific basis for the prevention and control of coal fines in deep CBM wells.
PubMed: 38882128
DOI: 10.1021/acsomega.4c03154 -
ACS Omega Jun 2024At present, the identification of the main factors controlling low-production coalbed methane (CBM) wells and production enhancement measures does not consider...
At present, the identification of the main factors controlling low-production coalbed methane (CBM) wells and production enhancement measures does not consider geological and reservoir differences between individual wells and the CBM production effect of well groups simultaneously. In view of this, an evaluation index system suitable for use on inefficient well-blocks was established, which involves their geological resource potential, ground stress, coal structure, and comprehensive permeability under engineering influences from a systemic perspective. The main geological engineering types were determined by zoning superposition, and the corresponding stimulation measures were proposed. The evaluation results of the Shizhuang South Block in the Qinshui Basin show that the area of interest can be divided into Class I, II, and III potential areas, of which the Class II potential areas are subdivided into six blocks. In Zone I, the horizontal well infill method is preferred to increase the CBM production from well groups. At the current level of technology, it is difficult to gain economic benefits from Zone III. In Zone II, these stimulation measures such as the infilling method of staged fracturing horizontal wells, refracturing under supplementary injection holes, roof fracturing, the combined method of acidification and secondary fracturing or nitrogen injection and secondary fracturing, the combined method of acidification and controlled displacement secondary fracturing, and controlled displacement repetitive roof fracturing, among others, can be adopted.
PubMed: 38882112
DOI: 10.1021/acsomega.3c10096