scholarly journals Effect of nitrate and its reduction products on the growth and activity of the rumen microbial population

1988 ◽  
Vol 59 (2) ◽  
pp. 301-313 ◽  
Author(s):  
J. P. Marais ◽  
Joha J. Therion ◽  
R. I. Mackie ◽  
A. Kistner ◽  
C. Dennison

1. The nature of the digestion-inhibiting substance in Kikuyu grass (Pennisetum clandestinum, Hochst), containing high levels of nitrate, was investigated using in vitro digestibility techniques.2. Nitrite, which accumulated during the reduction of nitrate to ammonia, seemed to be the primary factor reducing digestibility. Nitrate and ammonia did not affect digestion in vitro.3. Nitrite caused a reduction in the cellulolytic, xylanolytic and total microbial population, with a concomitant reduction in cellulase and xylanase activity of the digesta.4. The mode of action of nitrite on rumen microbial growth was investigated.5. The possibility that the growth of cellulolytic rumen microbes was depressed by a reduction in concentration of essential branched-chain volatile fatty acids by nitrite was discounted.6. Although nitrite caused a marked increase in the redox potential, due to its oxidizing properties, the more-positive redox potential did not reduce the digestibility of the grass.7. The growth of three of the four major cellulolytic bacteria commonly found in the rumen was severely depressed by nitrite, while some rumen bacteria were relatively insensitive to nitrite.8. Growth inhibition seemed to depend primarily on the extent to which these microbes derive their energy from electron-transport-mediated processes.9. It was suggested that, due to the sensitivity of some rumen bacteria to nitrite, digestibility and therefore animal performance could be affected long before clinical symptoms of nitrite toxicity become apparent.

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 422-423
Author(s):  
Aghata Silva ◽  
Aaron Norris ◽  
Arturo Franco ◽  
Felipe H De Moura ◽  
Mozart Fonseca

Abstract The objective of this study was to determine the influence of defatted hemp under three irrigation regimes (0, 100, and 200 mm: DF0, DF1, and DF2 respectively) on in vitro fermentation parameters relative to alfalfa (Medicago sativa). Fermentation kinetics was accessed through in vitro gas production technique. Two ruminally cannulated Angus steers were used as inoculum donors in four incubation runs. For each incubation, four 160-mL serum bottles containing 200 mg of air-dried samples were incubated in 14 mL of buffering media and 4 mL of rumen inoculum. Each incubation spanned 48h with gas production measured at 0, 3, 6, 12, 24, and 48-h post-incubation. In vitro true digestibility of dry matter (IVTDMD) and organic matter (IVTOMD), total gas production (TGP), metabolizable energy (ME) and total volatile fatty acids (VFA) were determined. Hemp and alfalfa were compared via orthogonal contrast using the GLIMMIX procedure of SAS (version 9.4) with treatment as fixed effect and run as a random. Relative to alfalfa (Alf) hemp displayed increased TGP (P < 0.01; 31.1 vs. 27.47 mL) that remained following correction for DM and OM (P ≤ 0.05). Similarly, IVTDMD and IVTOMD were higher for hemp (P < 0.01; 77.7 vs. 70.2% and 81.7 vs. 73.9%). Hemp yielded slightly higher ME (P = 0.03) but equivalent total VFA production when compared to Alf (P = 0.62), even when corrected for DM and OM. Irrigation at 200 mm decreased TGP and fermentability of fat-extracted hemp (p-value). Results also indicate that irrigation at its highest level is detrimental to the availability of ME for rumen microbes, but not with the expense of the in vitro digestibility (IVTDMD and IVTOMD) nor in total VFA produced. In conclusion, defatted hemp samples appear to have greater digestibility and ME with equivalent VFA production relative to alfalfa.


2011 ◽  
Vol 77 (8) ◽  
pp. 2634-2639 ◽  
Author(s):  
Zhenming Zhou ◽  
Qingxiang Meng ◽  
Zhongtang Yu

ABSTRACTThe objective of this study was to systematically evaluate and compare the effects of select antimethanogen compounds on methane production, feed digestion and fermentation, and populations of ruminal bacteria and methanogens usingin vitrocultures. Seven compounds, including 2-bromoethanesulphonate (BES), propynoic acid (PA), nitroethane (NE), ethyltrans-2-butenoate (ETB), 2-nitroethanol (2NEOH), sodium nitrate (SN), and ethyl-2-butynote (EB), were tested at a final concentration of 12 mM. Ground alfalfa hay was included as the only substrate to simulate daily forage intake. Compared to no-inhibitor controls, PA, 2NEOH, and SN greatly reduced the production of methane (70 to 99%), volatile fatty acids (VFAs; 46 to 66%), acetate (30 to 60%), and propionate (79 to 82%), with 2NEOH reducing the most. EB reduced methane production by 23% without a significant effect on total VFAs, acetate, or propionate. BES significantly reduced the propionate concentration but not the production of methane, total VFAs, or acetate. ETB or NE had no significant effect on any of the above-mentioned measurements. Specific quantitative-PCR (qPCR) assays showed that none of the inhibitors significantly affected total bacterial populations but that they did reduce theFibrobacter succinogenespopulation. SN reduced theRuminococcus albuspopulation, while PA and 2NEOH increased the populations of bothR. albusandRuminococcus flavefaciens. Archaeon-specific PCR-denaturing gradient gel electrophoresis (DGGE) showed that all the inhibitors affected the methanogen population structure, while archaeon-specific qPCR revealed a significant decrease in methanogen population in all treatments. These results showed that EB, ETB, NE, and BES can effectively reduce the total population of methanogens but that they reduce methane production to a lesser extent. The results may guide futureinvivostudies to develop effective mitigation of methane emission from ruminants.


2013 ◽  
Vol 64 (4) ◽  
pp. 409 ◽  
Author(s):  
Bidhyut Kumar Banik ◽  
Zoey Durmic ◽  
William Erskine ◽  
Phillip Nichols ◽  
Kioumars Ghamkhar ◽  
...  

Biserrula (Biserrula pelecinus L.) is an important annual pasture legume for the wheatbelt of southern Australia and has been found to have lower levels of methane output than other pasture legumes when fermented by rumen microbes. Thirty accessions of the biserrula core germplasm collection were grown in the glasshouse to examine intra-specific variability in in vitro rumen fermentation, including methane output. One biserrula cultivar (Casbah) was also grown at two field locations to confirm that low methanogenic potential was present in field-grown samples. All of the biserrula accessions had significantly reduced methane [range 0.5–8.4 mL/g dry matter (DM)] output compared with subterranean clover (28.4 mL/g DM) and red clover (36.1 mL/g DM). There was also significant variation in fermentability profiles (except for volatile fatty acids) among accessions of the core collection. Methanogenic potential exhibited 86% broad-sense heritability within the biserrula core collection. The anti-methanogenic and gas-suppressing effect of biserrula was also confirmed in samples grown in the field. In conclusion, biserrula showed variability in in vitro fermentation traits including reduced methane production compared with controls. This bioactivity of biserrula also persists in the field, indicating scope for further selection of biserrula as an elite methane-mitigating pasture.


2020 ◽  
Author(s):  
Hangshu Xin ◽  
Xin Liu ◽  
Xin Jiang ◽  
Chunlong Liu ◽  
Shuzhi Zhang ◽  
...  

Abstract Background: The objectives of this study were to evaluate the profiles of odd- and branched-chain fatty acids (OBCFA; including C15:0, iso-C15:0, anteiso-C15:0, iso-C16:0, C17:0, iso-C17:0 and anteiso-C17:0) during pure carbohydrates incubation in vitro and whether they correlated with ruminal fermentation parameters, microbial crude protein (MCP) synthesis, and bacterial populations. The pure substrates containing five different ratios of fiber and starch (F:S; 0:100, 25:75, 50:50, 75:25 and 100:0) were incubated for 6 h, 12 h, 18 h and 24 h. Results: Except iso-C17:0, OBCFA concentrations were interacted by F:S and incubation time. The highest concentration of total OBCFA was found in the fermented mixture after 24 h of incubation when the F:S = 0:100; while the lowest level was 1.65 mg/g DM produced after 6 h of incubation with F:S = 50:50. The concentrations of total volatile fatty acids (TVFA) and MCP remarkably decreased linearly as the inclusion of fiber in the substrates increased, as expected. The proportions of investigated cellulolytic bacteria in our study were increased linearly (or linearly and quadratically) while those of R. amylophilus and S. bovis were decreased as fiber inclusion increased. The correlation analysis indicated that iso-C16:0 concentration might have potential as a marker of productions of TVFA and MCP with ρ being 0.78 and 0.82 respectively. Compared to starch degrading bacteria, cellulolytic bacteria had more correlations with OBCFA profiles, and the strongest association was found on the population of R. flavefaciens with C15:0 concentration (ρ = 0.70). Conclusions: Our study shows there might be scope for iso-C16:0 to predict rumen productions of VFA and MCP. Notedly, this is the first paper reporting linkage of OBCFA with rumen function based on pure carbohydrate in vitro incubation, which would avoid confounding interference from dietary protein and fat presence. However, more in-depth experiments are needed to substantiate the current findings.


2002 ◽  
Vol 80 (11) ◽  
pp. 1930-1937 ◽  
Author(s):  
Iain J Gordon ◽  
F Javier Pérez-Barbería ◽  
Paloma Cuartas

The rumen microflora ecosystem adapts to the diet consumed by the animal. We tested the extent to which this adaptation facilitates or retards the digestion of plant-based forages. Following adaptation of sheep (Ovis aries) and red deer (Cervus elaphus) to diets containing different mixtures of alfalfa, grass, and heather (a dwarf shrub), an in vitro digestion technique was used to compare the ability of the rumen microflora to digest the mixtures of substrates to which they were adapted with their ability to digest different mixtures of the same substrates. In vitro digestion of different substrates was slightly greater in rumen liquor derived from sheep than in that derived from red deer for each of the different substrates, but the effect was not significant. Digestibility in sheep was independent of how the feed was presented (diet of equal proportions of alfalfa, grass, and heather in each meal (D-EQ): mean in vitro digestibility = 37.3%; alfalfa, grass, and heather presented sequentially on different days (D-SEQ): mean in vitro digestibility = 37.7%, SE of differences = 1.30%, p > 0.05). However, in red deer there was a significant effect of method of diet presentation (D-EQ: mean in vitro digestibility = 36.9%; D-SEQ: mean in vitro digestibility = 34.2%, SE of differences = 1.30%, p < 0.05), digestibility being substantially lower for D-SEQ than for D-EQ. Overall, the results demonstrated that whilst there were no species-specific differences in overall digestion efficiency, dietary adaptation had an effect on substrate digestion efficiency, with rumen microbes adapted to high-quality diets digesting these more efficiently than low-quality diets.


2018 ◽  
Vol 5 (2) ◽  
pp. 11
Author(s):  
Ali Bain ◽  
Komang G. Wiryawan ◽  
Dewi Apri Astuti ◽  
Chairrusyuhur Arman ◽  
Sri Suharti

ABSTRAKPenelitian ini bertujuan untuk mengevaluasi optimalisasi penggunaan level sabun kalsium yang berbeda dalam ransum secara in vitro terhadap karakteristik fermentasi, populasi mikroba dan kecernaan nutrien ransum, menggunakan sumber inokulum cairan rumen sapi Bali. Penelitian dilaksanakan menggunakan rancangan acak kelompok dengan 4 jenis perlakuan dalam 3 ulangan.  Ransum penelitian terdiri atas : R1, 40% rumput lapang (RL) + 60% konsentrat (K), R2 (40% RL + 60% K, mengandungn 2.5% SCa-kedelai), R3 (40%  RL + 60% K, mengandung 5% SCa-kedelai), R4 (40%  RL + 60% K, mengandung 7.5% SCa-kedelai). Variabel yang diukur terdiri atas karakteristik fermentasi in vitro (pH, N-NH3, produksi total volatile fatty acids), populasi mikroorganisme (total bakteri dan total protozoa), dan kecernaan nutrien (kecernaan bahan kering dan kecernaan bahan organik). Data dianalisis menggunakan analysis of varians  (ANOVA) dan perbedaan antara perlakuan diuji dengan Duncan’s Multiple Range Test.  Hasil penelitian menunjukkan, penambahan SCa-kedelai pada level yang berbeda dalam konsentrat tidak mempengaruhi pH, konsentrasi amonia, populasi mikroba, kecernaan bahan kering dan kecernaan bahan organik fermentasi tetapi berpengaruh sangat nyata (P<0.002) terhadap produksi total VFA. Produksi total VFA tertinggi diperoleh pada ransum perlakuan R4 (konsentrat yang mengandung 7.5% SCa-kedelai). Produksi total VFA tertinggi diperoleh pada perlakuan R4 dan produksi total VFA paling rendah terjadi pada perlakuan ransum R1 (kontrol).  Produksi total VFA  ransum R1 dan R2 dan ransum R2 dan R3 tidak berbeda nyata namun produksi total VFA ransum R3 lebih tinggi dibanding ransum kontrol. Penambahan SCa-kedelai dalam konsentrat menghasilkan produksi total VFA tetinggi namun mulai menekan populasi total bakteri. Mempertimbangkan hasil peubah fermentasi dan populasi mikroba serta biaya pembuatan produk sabun kalsium, SCa-kedelai pada level 5% merupakan level penggunaan SCa-kedelai yang terbaik dalam ransum.Kata kunci: sabun kalsium, fermentasi, in vitro, kecernaanABSTRACTThe study to evaluate the optimalization the different level of soybean oil calcium soap (CaS-soybean) in ration on in vitro fermentation using Bali cattle rumen fluid. The experiment was arranged in a complete randomized block design with 4 different ration treatments and 3 replicates. Ration treatments were R1: 40% native grass (NG) + 60% concentrate (C), R2 : 40% NG + 60% C, supplemented with 2.5% soybean oil calcium soap (CaS-soybean), and R3 (40% NG + 60% C, supplemented with 5.0% CaS-soybean and R4 (40% NG + 60% C, supplemented with 7.5% CaS-soybean). Variables measured were fermentation characteristics (pH, NH3-N, total volatile fatty acids), microbial population (total bacteria and total protozoa), and nutrient digestibility (dry matter and organic matter digestibility). Data were analyzed using analysis of variance (ANOVA) and the differences between treatments means were examined by Duncan Multiple Range Test. Results of the study  showed that the four different level of CaS-soybean in ration did not have any significant effect (P>0,05) on pH, NH3-N, total bacteria, total protozoa, dry matter and organic matter digestibility. The treatments significantly increased (P<0.05) the production of total volatile fatty acids.  The highest production of total VFA was obtained from ration R4 (concentrate containing 7.5% CaS-soybean) and the lowest was obtained from treatment R1 (control). There were no significant differences between R1 and  R2, and between R2 and R3 on the total VFA production. However, the total productions of VFA in ration R3 were higher than that of the control ration. The addition of CaS-soybean in the concentrate had increased the total production of VFA, but at the same time, it began pressing the total population of bacteria. Considering the results of the fermentation variables and microbial population as well as the cost of making calcium soap products, CaS-soybean at 5% level was selected as the best level of CaS-soybean in ration.Keywords : calcium soap, fermentation, in vitro, digestibility


Sign in / Sign up

Export Citation Format

Share Document