Ml Of Rumen Fluid Research Articles

PSVI-6 Genomic determinants of the rumen microbiome and metabolome in Angus steers

Abstract The rumen microbiome provides approximately 70% of energy required for the ruminant host through fermentation byproducts. Due to microbial impacts on host health and productivity, several studies have associated microbiome and metabolome variation with important sustainability phenotypes, such as feed efficiency and methane emissions. Recent studies have indicated the microbial communities present in rumen fluid are under low-to-moderate host genetic control. However, microorganisms present on the rumen wall have been underrepresented in research, negating their unique role in host-microbiome interactions. Current studies investigating heritability of the rumen planktonic microorganisms are plagued by small sample sizes, high management and breed heterogeneity, and low resolution for classifying microbial communities. To determine the heritability of the rumen fluid and epithelium-associated microbiome and metabolome, Angus steers (n = 350) were enrolled in a 70-d feed efficiency trial, where real-time dry matter intake was measured. Body weights were collected throughout the trial to calculate average daily gain and residual feed intake. Mid-trial, a novel surgery method was used to swab the rumen wall to capture epithelium-associated microorganisms. On d 70, 50 mL of rumen fluid was obtained from steers using orogastric tubing for collection of planktonic microbial communities. Metagenomic DNA extracted from both rumen fluid and epimural samples was used for reduced representation sequencing to predict microbial features such as diversity, composition, and putative function. Genomic DNA isolated from whole blood was used to perform low-pass whole genome sequencing for use in downstream heritability estimates and variant association analyses. Many core microbial abundances are under low-to-moderate host genetic control (h2 > 0.15; P < 0.05); however, many microorganisms had low heritability estimates (h2 < 0.10). Preliminary genome-wide associations studies are vastly underpowered to detect host genetic variants associated with microbial features, but data generated using the total number of animals will better refine these polymorphisms. Several key heritable metabolites were identified in amino acid metabolism pathways in rumen fluid (P < 0.05). The rumen microbiome appears to act as a complex polygenic trait and incorporating microbial features into prediction models may improve feed efficiency estimations. Understanding host genetic control of the rumen microbiome and metabolome may empower downstream applications to enhance genomic and phenotypic predictions for feed efficiency and other sustainability traits in beef cattle.

Insights into Effects of Combined Capric and Lauric Acid on Rumen Bacterial Composition.

This study used next-generation sequencing to assess the impact of combined capric acid (C10) and lauric acid (C12) on the ruminal bacterial composition. Eight Holstein cows were randomly assigned to two groups using a cross-over design. The cows were fed two silage-based diets with the addition of either 100 g of stearic acid per cow per day (control), or 50 g of capric acid and 50 g of lauric acid per cow per day (C10 + C12). On day 18, 250 mL of rumen fluid was collected from each cow, and DNA was isolated, amplified, and sequenced. Treatment did not alter bacterial diversity indices, the relative abundance of archaea, nor the fiber-degrading microorganisms, except for a decrease in Fibrobacter (from 2.9% to 0.7%; p = 0.04). The relative abundance of Prevotellaceae decreased (from 39.9% to 29.6%; p = 0.009), which is notable because some members help to efficiently utilize ammonia by releasing it slowly into the rumen. Furthermore, the relative abundance of Clostridia increased (from 28.4% to 41.5%; p = 0.008), which may have aided the increased ammonia-nitrogen levels in the rumen, as this class contains hyperammonia-producing members. Our study reveals alterations in bacterial abundances with implications for rumen ammonia levels, offering insights into potential strategies for modulating rumen fermentation processes and methane production in ruminant livestock.

Manipulation of neonatal ruminal populations at birth results in sustained effects on microbial populations and measures of health and production in merino and suffolk lambs

The efficiency of the microbial-driven fermentation process in the rumen is closely related to the efficiency of the ruminant host. This experiment examined the effect of manipulating the neonatal microbiota on postnatal development, immune function and productivity (liveweight gain and wool growth parameters). The trial examined the differences between naturally inoculated lambs (maternal control, n = 21) and those given ruminal fluid, which had been collected from ruminally-cannulated ewes, fed either a roughage diet (roughage, n = 14), or a grain-based diet (high grain, n = 14). At lambing, newborn lambs were tagged and weighed. Inoculation lambs received 10 ml of rumen fluid per inoculation, daily, for a total of 7 inoculations. Live weight, body condition scores, wool growth (greasy and clean wool weights), wool length, mean fibre diameter, and differential blood cell counts, and IgG and IgA in both blood and saliva) were quantified from birth until week 18 (slaughter). Total feed intake was recorded from weaning. Ruminal fluid was collected by stomach tube from 12 lambs from each treatment group and their dams (n = 7–8 per treatment, with the lower number of ewes coming about through ewes that had twins) at time of weaning (week 10). The pH of the ruminal fluid, the density of ciliated protozoa in ruminal fluid, and the composition of the ruminal bacterial populations were analysed. At slaughter (week 18), ileal samples were taken from the same focal lambs as were used for microbial analysis. The artificial inoculations resulted in significant differences in ruminal bacterial genera to those of naturally inoculated lambs at time of weaning (some 3 months post-lambing). Significant differences were also apparent in ileal bacterial communities at slaughter, between lambs which had received the inoculum from roughage-fed ewes and naturally inoculated lambs. Both the efficiency (growth, condition, feed conversion efficiency, carcass weight) and indices of health (mortalities, red blood cell count, blood haemoglobin concentration, haematocrit, and eosinophil counts) of the inoculated animals, were affected negatively by the inoculations ( < 0.05). There was a significant interaction between inoculum source and breed in terms of effects on all parameters measured. The effects of the high grain inoculation were significantly affected by breed, with high grain merinos found to have reduced mean fibre diameter (P < 0.05) and increased wool growth relative to the maternal control (P = 0.035). This effect was not noted in the suffolks. In summary, we have demonstrated that long-term effects on ruminal and intestinal microbiota can be generated by intervention in the normal process of ruminal inoculation in neonatal lambs. Moreover, there appeared to be genetic differences in response to artificial inoculation. Whilst the effects of artificial inoculation in this trial were negative in terms of indices of health and production, further studies of maternal diet and its effects on the natural establishment of the neonatal microbiota are warranted given the persistence of the effects and the interaction with breed.

The influence of virginiamycin on digestion and ruminal parameters under feedlot conditions.

This experiment aimed to assess the impact of virginiamycin on in vitro gas production dynamics, rumen kinetics, and nutrient digestibility in beef steers fed a grain-based diet. Nine ruminally cannulated British-crossbred steers (596 ± 49kg) were assigned to this experiment. Animals were housed in three pens (n = 3/pen) equipped with a Calan gate feed system and water troughs. Pens were enrolled in a 3 × 3 Latin square design containing three periods of 16 d, and a 5-d washout interval between periods. Dietary treatments consisted of virginiamycin (VM) administration at 0 (VM0), 180 (VM180), or 240mg/d (VM240). During days 15 and 16 of each period, about 600mL of rumen fluid and urine samples were collected before (0h), and at 4, 8, 12, and 16h after the morning feed (0730 hours), rumen inoculum was used to take pH and redox potential measurements immediately after collection using a portable pH and redox meter, and subsamples were taken for volatile fatty acids (VFA) and NH3-N analyses, and urine samples were composited daily and analyzed for creatinine and purine derivatives (PD) content to estimate microbial crude protein flow. During the 4-h post-morning feed rumen collection, rumen inoculum was utilized to perform in vitro gas production measurements. Fecal samples were collected on day 16 of each period to estimate nutrient digestibility using acid detergent insoluble ash as an internal marker. Animals were considered the experimental unit for the statistical analyses, and periods and squares were included as random variables. The total and rate of gas production were similar among treatments (P ≥ 0.17). The second-pool (i.e., fiber) gas production increased linearly as VM inclusion increased (P = 0.01), with VM240 being greater compared to VM180 and VM0 (7.84, 6.94, and 6.89mL, respectively). Ruminal pH linearly increased as VM increased, with VM240 being greater than VM0 and VM180 intermediate (5.90, 5.82, and 5.86, respectively; P = 0.03). The VFA concentrations did not differ (P ≥ 0.13), but the acetate-to-propionate ratio was the highest in VM240 (P = 0.005). Branched-chain VFA increased (P ≤ 0.03) while lactate concentrations decreased (P = 0.005) linearly with VM. The ruminal NH3-N concentration was the lowest in the VM0 (P = 0.006). The estimated absorbed PD, purine derivative to creatinine index, and microbial N flow increased linearly with VM (P ≤ 0.07). The provision of VM influenced rumen dynamics in a dose-dependent manner.

342 Effectiveness of Liver Abscess-Controlling Antibiotic on Rumen Kinetics of Beef Steers Consuming a High-Grain Diet

Abstract Virginiamycin (VM) possesses antimicrobial properties due to its blocking of protein synthase in Gram-positive bacteria, allowing it to reduce lactic acidosis and the incidence of liver abscesses in ruminants. Ruminal acidosis is a common metabolic disorder that affects feedlot and dairy cattle and occurs when the supply of organic acids from fermentation exceeds its absorption and degradation, accumulating acid content in the rumen. The objective of this study was to evaluate the effects of three different doses of VM administration on in vivo and in vitro ruminal digestion kinetics of beef steers consuming a high-grain diet [metabolizable energy (ME): 2.99 Mcal/kg; Crude Protein (CP): 15.2 % dry matter basis (DM)]. Nine ruminally cannulated British-crossbred steers (596 ± 49 kg) were assigned to this experiment. Animals were housed in three pens (n = 3/pen) equipped with a Calan gate feed system and water trough. Pens were enrolled in a 3×3 Latin square design containing three periods of 16 d, and a 5-d washout interval between periods. Dietary treatments consisted of VM administration at 0 mg/d (VM0), 180 mg/d (VM180), and 240 mg/d (VM240). During d 15 and 16 of each period, about 600 mL of rumen fluid was collected before (0 h) and at 4, 8, 12, and 16 h relative to the morning feed (0730 h) pH and redox potential (Eh) measurements were taken immediately after collection using a portable pH and redox meter, and subsamples were taken for volatile fatty acids (VFA), and NH3-N analyses. During the 4-h post-morning feed rumen collection, rumen inoculum was utilized to perform in vitro gas production (IVGP) measurements. All statistical procedures were performed using SAS software where steer was considered the experimental unit, and period and square were included as random. Acetate, propionate, and total VFA did not differ among treatments (P ≥ 0.50), whereas butyrate increased linearly (P = 0.033) as the VM dose increased. Acetate:propionate ratio did not differ among treatments (P = 0.273). Lactate concentration decreased linearly (P = 0.027) as the VM dose increased; likewise, pH increased linearly (P = 0.019) as the VM dose increased. Branched-chain VFA and NH3-N concentrations increased linearly (P ≤ 0.056) as the VM dose increased. The total and rate of gas production were similar among treatments (P ≥ 0.161). However, second-pool gas production increased linearly as VM inclusion increased (P = 0.023). The in vitro neutral detergent fiber digestibility did not differ among treatments (P = 0.984). The provision of VM altered the rumen dynamics in a dose-dependent manner. Animals consuming high-grain diets will likely promote rumen health through a more stable pH and fermentation profile.

Effect of sun dry brewer spent yeast on chemical composition, in vitro digestibility, and ruminal degradation kinetics of wheat straw

BackgroundDry brewer spent yeast (DBSY) has high crude protein (CP) (43.2%) and metabolizable energy (14.3 MJ/kg) contents and it is an alternative animal feed for the improvement of the productive and reproductive performance of the animals. This study was conducted to evaluate the effect of DBSY on the chemical composition, in vitro digestibility, and in situ degradability of wheat straw (WS).MethodsLiquid brewer spent yeast (BSY) and water was mixed at a ratio of 1:5, respectively. The mixed debris soaked for 7 h in a 200-L plastic bucket. The water accumulated above the biomass was removed by tilting the container after the BSY was soaked in water. After three days of sun drying, DBSY was collected and removed with a scraper. The DBSY and wheat straw (WS) mixed uniformly. Different ratios of DBSY: WS (0:100, 10:90, 20:80, 30:70, 40:60, and 50:50, respectively, on a DM basis) were prepared. Based on these ratios, the experiment was subjected to a completely randomized design with six treatments comprising DBSY0, DBSY10, DBSY20, DBSY30, DBSY40, and DBSY50. Rumen liquor was collected from the three cannulated Boran-Friesian steers (42 months old and weighed 480 kg). The steers were fed natural pasture hay ad libitum supplemented with 2 kg concentrate per day/head. The sample was incubated in a test tube at 39 °C for 48 h with 10 ml of rumen fluid and 50 ml of buffer solution. The enzymatic digestion with acid pepsin solution was continued for another 48 h. Blank and standard samples were also incubated with buffered rumen fluid for correction and precision check-up of in vitro organic matter digestibility. Digestible organic matter in the dry matter (DOMD) was determined after drying and ashing the residues. The sample (3 g and 2 mm sieve size) with nylon bags (6.5 X 14 cm and 50 μm pore size) was entered sequentially and manually pressed deep into the liquid phase of the ventral sac of the rumen and incubated in the rumens (6, 12, 24, 48, 72, and 96 h) of three fistulated Boran × Holstein–Friesian steers. After removing the bags from the rumen, it was washed in running water for 20 min. The bags with residues were dried at 55 °C for 72 h in an air-forced oven, hot weighed, and finally, the residues recovered for further CP and neutral detergent fibre (NDF) analysis.ResultsThe highest ash, metabolizable energy, estimated digestible CP, DOMD, CP, Ca, P, Cu, Zn contents and the better DM, NDF, and CP ruminal degradability, and the lowest (P < 0.01) crude fibre, acid detergent fibre, NDF, K & Fe contents were observed in DBSY50 than the other DBSY inclusion level. In DBSY50, the potential degradability (PD) and effective degradability (ED) for DM of WS were improved by 52.22% and 56.17%, respectively. In DBSY50, PD and ED (NDF) in WS were increased by 60.34% and 65%, respectively. Similarly, in DBSY50, PD and ED (CP) of WS also improved by 54.20% and 63%, respectively.ConclusionThe inclusion of DBSY can improve the limited utilization of wheat straw, but this study should be verified with a feeding experiment to identify and recommend the most promising, economical and biological inclusion level of DBSY.

ВЛИЯНИЕ МИНЕРАЛЬНО-ВИТАМИННОЙ ДОБАВКИ НА ИНФУЗОРНУЮ ФАУНУ РУБЦА И МОЛОЧНУЮ ПРОДУКТИВНОСТЬ КОРОВ

The article presents the results of research on the use of mineral and vitamin supplements in the diets of dairy cows and its effect on the microfauna of the rumen and dairy productivity of animals. The object of research was highly productive cows during the period of milking. As a result of the conducted studies, it was found that the use of a feed additive contributed to the optimization of digestive processes by increasing the density of rumen infusoria in 1 ml of rumen fluid in lactating cows of the experimental groups compared with peers from the control group by 22.6–23.1 %, which is reliable (p ≥ 0,95). The feed additive had a positive effect on increasing the biodiversity of infusoria in the rumen of ruminants, creating more favorable conditions for the formation and growth of microfauna, and, consequently, for improving the digestibility of nutrients consumed feed, as evidenced by data on the dairy productivity of animals. During the period of the experiment, the average daily milk yield according to the results of control milkings of cows receiving «Minvit 6.1-Mama» in the amount of 150 g was 31.0 ± 0.6 kg, which is 8.0 % (p ≥ 0.99) more than animals from the control group. Cows of the experimental group 2 had an average daily milk yield of 31.8 ± 0.71 kg, which is 10.8 % (p ≥ 0.99) higher than the same indicator compared to peers from the control group. Thus, the use of mineral and vitamin supplement «Minvit 6.1-Mama» in the feeding of dairy cows contributes to the optimization of scar digestion while increasing the milk productivity of animals. The maximum biological and zootechnical effect is manifested by the introduction of a feed additive in the amount of 200 g per head per day

Effect of urea in steamed sago waste on rumen fermentation parameters in vitro tested

This study aims to determine urea’s effect in steamed sago waste on rumen fermentation parameters in vitro testing. Sago waste was dried for two days, discarded fibre sticks, steamed for 30 minutes, cooled and dried. Weighed 250 g of steamed sago waste, added urea with levels of 0%, 2%, 4% and 6%. Weighed 0.5 g of samples per treatments, inserted in fermentor tubes, added 10 ml buffer and 10 ml of rumen fluid (1:1). Fermentor tubes are inserted in waterbath with a temperature of 39°C, flowed with CO2 gas and covered with a valved rubber cover. For NH3 and VFA testing, incubation was carried out for 4 hours, while for DMD and OMD testing, incubation was carried out for 48 hours. The data obtained were analyzed using a completely random design with four urea level treatments (0%, 2%, 4%, 6%), with five replications. The results showed that increase of urea level up to 6%, increasing (P<0.01) NH3. The increase of urea level 2%, increasing (P<0.01) VFA, DMD and OMD. The increase of urea levels 4% and 6%, not significant effect on DMD and OMD, while at urea level 6%, decreasing (P<0.01) VFA. It can be concluded that urea was added in steamed sago waste, have an optimal effect on the rumen fermentation parameters at level 2–4%.

Short communication: Saliva and salivary components affect goat rumen fermentation in short-term batch incubations

The research about the role of saliva in ruminants has been mainly focused on its buffering capacity together with facilitation of the rumination process. However, the role of salivary bioactive components on modulating the activity of the rumen microbiota has been neglected until recently. This study developed an in vitro approach to assess the impact of different components in saliva on rumen microbial fermentation. Four different salivary fractions were prepared from four goats: (i) non-filtrated saliva (NFS), (ii) filtrated through 0.25 µm to remove microorganisms and large particles (FS1), (iii) centrifuged through a 30 kDa filter to remove large proteins, (FS2), and (iv) autoclaved saliva (AS) to keep only the minerals. Two experiments were conducted in 24 h batch culture incubations with 6 ml of total volume consisting of 2 ml of rumen fluid and 4 ml of saliva/buffer mix. In Experiment 1, the effect of increasing the proportion of saliva (either NFS or FS1) in the solution (0%, 16%, 33% and 50% of the total volume) was evaluated. Treatment FS1 promoted greater total volatile fatty acids (VFA) (+8.4%) and butyrate molar proportion (+2.8%) but lower NH3-N concentrations than NFS fraction. Replacing the bicarbonate buffer solution by increasing proportions of saliva resulted in higher NH3-N, total VFA (+8.0%) and propionate molar proportion (+11%). Experiment 2 addressed the effect of the different fractions of saliva (NFS, FS1, FS2 and AS). Saliva fractions led to higher total VFA and NH3-N concentrations than non-saliva incubations, which suggests that the presence of some salivary elements enhanced rumen microbial activity. Fraction FS1 promoted a higher concentration of total VFA (+7.8%) than the other three fractions, and higher propionate (+26%) than NFS and AS. This agrees with findings from Experiment 1 and supports that ‘microbe-free saliva’, in which large salivary proteins are maintained, boosts rumen fermentation. Our results show the usefulness of this in vitro approach and suggest that different salivary components can modulate rumen microbial fermentation, although the specific metabolites and effects they cause need further research.

Pre-weaning Ruminal Administration of Differentially-Enriched, Rumen-Derived Inocula Shaped Rumen Bacterial Communities and Co-occurrence Networks of Post-weaned Dairy Calves.

Adult rumen fluid inoculations have been considered to facilitate the establishment of rumen microbiota of pre-weaned dairy calves. However, the sustained effects of the inoculations remain to be explored. In our previous study, 20 pre-weaned dairy calves had been dosed with four types of adult rumen inoculums [autoclaved rumen fluid, bacterial-enriched rumen fluid (BE), protozoal-enriched (PE), and BE + PE] weekly at 3 to 6 weeks of age. To verify the sustained effect of adult rumen inoculation, the rumen bacterial communities, fermentation characteristics, and animal performance measurements were measured after sacrifice from 20 post-weaned dairy bull calves (9 weeks of age). Ruminal pH tended to be lower in BE treated calves (n = 10). All PE treated calves had rumen ciliates (>104 cells per ml of rumen fluid). PE treated calves had greater VFA concentrations (P = 0.052), lower molar proportions of isobutyrate (P = 0.073), and butyrate (P = 0.019) compared to those of control calves. No treatment differences were found in all animal performance measurements. Both PE and BE inocula increased bacterial species richness, Faith’s phylogenetic diversity, and Shannon’s index in rumen liquid fractions. However, the relative proportion of those bacterial taxa possibly transferred from the donor’s rumen was minor. Microbial network analysis showed different co-occurrence and mutually exclusive interactions between treatments of microbial inoculations. Collectively, adult rumen inoculations in pre-weaned dairy calves slightly altered the rumen bacteriome of post-weaned calves without changing fermentation and animal performance.

Rumen fluid transplantation affects growth performance of weaned lambs by altering gastrointestinal microbiota, immune function and feed digestibility

Although rumen fluid transplantation (RT) has been developed to confer benefits for adult ruminants by altering gastrointestinal tract microbiota, the question remains whether RT can also benefit weaned lambs. Hence, in this study, thirty-eight pre-weaning lambs were randomly assigned to one of three treatment groups: control lambs (CON) received 25 ml of normal saline solution, and lambs in two RT groups received 25 ml of rumen fluid either from 3-month-old lambs (LT) or from one-year-old adult ewes (AT). The effects on their growth performance, nutrient digestibility, some blood parameters and gastrointestinal tract microbiota were monitored. There were differences (P < 0.05) in rumen bacterial composition between the groups at weaning, at 3 months and at 1 year. Rumen fluid transplantation decreased (P < 0.05) average daily feed intake, average daily gain in live weight and apparent digestibility of ether extract in the LT group, and it decreased (P < 0.05) apparent digestibility of NDF and ADF in the AT group. Rumen fluid transplantation also increased (P < 0.05) concentrations of serum immunoglobulin A in the AT group and increased (P < 0.05) serum concentrations of interleukin-6, interferon alpha and D-lactate in both LT and AT groups. Bacterial α-diversity in the rumen and rectum was not affected by RT (P > 0.05), but a bacterial community change was observed after RT, and the abundance of some dominant bacteria in both rumen and rectum changed after RT (P < 0.05). Analysis of correlations between the parameters indicated that the altered gastrointestinal microbiota and accelerated maturity of rumen microorganisms induced by RT caused some impairment of gastrointestinal integrity and immunity, which led to decreased feed intake, reduced feed digestibility and lower growth performance of the weaned lambs. In conclusion, rumen fluid transplantation altered the gastrointestinal microbiota causing adverse effects on feed intake, feed digestibility and growth performance of the weaned lambs.

Proof of Concept of Culturomics Use of Time of Care.

Culturomics, a high throughput culture method with rapid identification of the colonies by Matrix Assisted Laser Desorption Ionization/Time Of Flight Mass Spectrometry (MALDI-TOF MS), has demonstrated its contribution to the exploration of the gut microbiota over the past 10 years. However, the cost, work time and workload, considerably limit its use on a large scale or emergency context. Here, by testing two different stool samples, including a stool sample from a patient requiring rapid immunotherapy treatment, we tested a new fast culturomic protocol using two pre-incubation media, blood culture bottle and YCFA modified medium. Both media were supplemented with 2 ml of rumen fluid filtered at 0.2 μm and 2 ml of defibrinated and sterile sheep blood. Unlike the standard culturomics, subculturing of blood culture bottle were performed at reduced incubation time (3 h, 6 h, 9 h, 24 h) and at a longer incubation time (3 days, 7 days, and 10 days) at 37°C. By testing 5,200 colonies per MALDI-TOF MS and obtaining a comparable number of cultured bacterial species (131 to 143) in a stool sample, this new protocol reduced the number of colonies tested by 57%, working time by 78.6% and cost by 72.2%. In addition, we highlighted that the proportion of strict anaerobic species has increased by 24%, known to be the preferential targets for biotherapy, including Faecalibacterium prausnitzii, Akkermansia muciniphila, Christensenella minuta, and Phascolarctobacterium faecium. Finally, this work showed that some bacterial species grew earlier but disappeared with prolonged incubation times.

In vitro metabolism of red clover isoflavones in rumen fluid.

The degradation of red clover isoflavones was studied in vitro using a rumen fluid buffer system. Various amounts of red clover extract (5-75mg) together with hay or concentrate-rich diet were added to 40ml of rumen fluid obtained from non-lactating and lactating dairy cows, respectively, and incubated for 0, 3, 6, 12 or 24hr. Following incubation, concentrations of daidzein, genistein, formononetin, biochanin A and equol were determined in the samples. After 3hr of incubation, isoflavone metabolism and equol production could be observed. The results obtained indicate that hay diet provides better conditions for isoflavone metabolism, as concentrations of daidzein, formononetin and biochanin A were higher in incubations based on the concentrate-rich diet and the production of equol was higher in incubations based on the hay diet. Furthermore, in incubations with higher amounts of added clover extract, a decrease in equol production was observed. Further studies are needed to clarify the role of adaptation of rumen microflora on isoflavone degradation kinetics and to clarify the interrelationship between various dietary factors, rumen microbiota and isoflavones. The knowledge of isoflavone metabolism kinetics in dependence on studied factors will be useful for the optimization of feeding dose.

Producción de metano y bióxido de carbono in vitro de pastos tropicales de la costa de Oaxaca, México

Los pastos tropicales poseen baja concentración de proteína cruda y mayor fibra detergente neutra. Los pastos fermentados en el rumen, presentan diferentes valores de digestibilidad, concentración de ácidos grasos volátiles (AGV), producción de metano (CH4) y bióxido de carbono (CO2). Objetivo: determinar la composición química, caracterizar la fermentación y estimar la producción de CH4 y CO2 in vitro en pastos tropicales de Oaxaca. Materiales y métodos. Los pastos (0.5 g de materia seca): Cynodon nlemfuensis, Andropogon gayanus, Penissetum purpureum cv. Taiwán Morado, Penissetum purpureum cv. Maralfalfa y Panicum maximum, fueron incubados con 45 mL de medio para microorganismos anaerobios, y depositados en viales de vidrio de 100 mL mantenidos en condiciones anaerobias con CO2. Los pastos fueron inoculados con cinco mL de fluido ruminal de bovino e incubados a 39 °C durante 72 h. A las 6, 12, 24, 48 72 h se determinó la producción de biogás y la población de microorganismos. La concentración de AGV, pH y degradación de la materia seca in vitro (DIVMS) se determinaron a 72 h. A 24, 48 y 72 h se midió la producción de CH4 y CO2. Las variables se evaluaron mediante un diseño completamente aleatorizado utilizando cinco repeticiones por tratamiento, la comparación de medias se realizó mediante la prueba de Tukey. Cynodon nlemfuensis tuvo el mayor contenido de proteína cruda (P = 0.05). Las poblaciones de bacterias celulolíticas presentaron menor conteo en Andropogon gayanus así como en Panicum máximum (P &lt; 0.05). Cynodon nlemfuensis, Andropogon gayanus y Pennisetum purpureum cv. Taiwán Morado presentaron menores concentraciones de acetato (P &lt; 0.05), Pannicum maximum tuvo mayor concentración de propionato (P &lt; 0.05). Pennisetum purpureum cv. Maralfalfa presentó la mayor DIVMS y produjo menor volumen de CH4 (P &lt; 0.05), Cynodon nlemfuensis y Pannicum maximum produjeron menores volúmenes de CO2 (P &lt; 0.05).

PENGARUH BIODELIGNIFIKASI DAUN SAWIT MENGGUNAKAN KAPANG Phanerochaete Chrysosporium YANG DISUPLEMENTASI DENGAN MINERAL CA TERHADAP KARAKTERISTIK CAIRAN RUMEN SECARA In Vitro

The aims of this research to see the effect of biodelignification of palm leaves using Phanerochaete chrysosporium againts total VFA, NH3 and pH. This study used factorial randomized block design (4x3) with 3 replications. Factor A is a dose of mineral addition in which A0 = 0 ppm Ca mineral, A1 = 1000 ppm Ca mineral, A3 = 1500 ppm Ca mineral, and A4 = 2000 ppm Ca mineral. Factor Y is the time of fermentation Y1 = 10 days, Y2 = 15 days, and Y3 = 20 days. Fermentation of palm leaves using Phanerochaete chrysosporium at a dose of Ca 2000 ppm mineral with a fermentation time of 10 days showed a total of 121.25 mM VFA more than any other treatment, and the amount of NH3 produced 14.80 mg / 100 ml of rumen fluid, and pH ranges from 6.79 to 6.86. The resulting pH is still in a condition where rumen microbes can grow optimally.Keywords: Biodelignification, Phanerochaete chrysosporium, NH3, pH, Volatille Fatty Acid (VFA)

PSII-42 Kinetics of methanogenesis and acetogenesis under normal rumen conditions

Abstract Researchers are investigating numerous methods to reduce enteric methane emissions and improve the sustainability of US animal agriculture. Methane emissions from the rumen depend on principles of kinetics, where the profile of fermentation products depends on relative rates of competing reactions, substrate concentrations or enzymatic activities. We investigated the kinetics of methanogenesis and related VFA production under increasing concentrations of infused hydrogen. The H2 (0, 0.3, 0.5, 1, 2, 4, 6, 8, 10 mL) was added to Hungate tubes containing 10 mL of rumen fluid with 10 mL of CO2 headspace gas. Then H2, CH4 and CO2, and volatile fatty acid (VFA) concentrations were measured after 0 and 1 h incubation at 39 °C. Data were fit to a non-linear Michaelis-Menten (M-M) model to estimate Vmaxand Km. For initial rumen fluid without added H2gas, there was an increase in CH4, slight decrease in H2, and disappearance of acetate and propionate. When H2was added, H2disappearance increased linearly, and methane, acetate and propionate increased non-linearly. For example, methanogenesis Vmax was 0.209 mM 10mL-1minute-1 with Km of 67.2 mM (RMSPE = 0.09, n = 9). The ratio of appearance of CH4 to disappearance of H2 was 0.15, showing 60% of H2 disappearance was accounted for by methanogenesis. The H2 addition shifted fermentation from VFA degradation to synthesis via saturable pathways (e.g. at Vmax). Results show that rumen fluid has enzyme activity such that as H2 gas is made available to rumen fluid, most H2is used for methane and VFA synthesis, and rates and proportions of H2 utilization for different pathways can be measured in vitro.

The Effect of Fitosan Supplementation on Methane Production in Cow’s Rumen Liquid by In Vitro Method

Methane is one of greenhouse emission gas causing climatic change and global warming. The biggest source of methane comes from the livestock sector. The objective of this study was to investigate the effects of fitosan on methane production by using in vitro method. Before the in vitro test, the antimicrobial test of fitosan was measured by looking at the clear zone of the media containing bacteria Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). In vitro method should be done by adding fitosan (0,15 mL, 0,3 mL, and 0,6 mL/30 mL media) and grass field powder into cow’s rumen liquid. Based on the results, fitosan has an antimicrobial ability to decrease the microbial activities both of Gram-positive or Gram-negative. Testing with the in vitro method showed that fitosan have the potency to reduce methane gas production about 23.34 – 31.85% compared to controls (without fitosan). The best treatment is treatment with the addition of fitosan with concentration of 0.6 mL per 30 mL of rumen fluid.

Effects of Adsorbent and Phytobiotic on Density of Rumen Infusoria and Cow Milk Production

Effects of the Vermiculite adsorbent and the Ruminant Extract phytobiotic on the density of infusoria inhabiting rumen and the cow milk production have been studied. It was ascertained that these supplements had a positive effect on the density of rumen infusoria when they were added to the rations for the lactating cows. Their populations in the animals provided with the combined Vermiculite and Ruminant Extract supplement and the only Ruminant Extract phytobiotic comprised 309 000 and 234 000 specimens per 1 mL of rumen fluid, respectively; in the control animals, there were 203 000 specimens per 1 mL of rumen fluid. The populations of infusoria were increased by 52.3 and 15.4%, respectively. Therefore, the Vermiculite adsorbent and the Ruminant Extract phytobiotic contributed to improving the cow milk production by 4.1 and 3.8%, respectively.

Study of electrochemical process conditions for the electricity production in microbial fuel cell

ABSTRACTThe aim of this study was to focus on the optimization of various process parameters such as time (days), pH, and electrode type on electricity production by a microbial fuel cell (MFC). The efficiency of MFC was examined based on the current (A) and potential (V) measurements. In MFC, the anode section was filled with 500 mL of rumen fluid, slaughter house waste, and 2 g of hay as substrate. The cathode section was filled with distilled water, which acted as the air cathode. The results obtained confirmed that copper anode explores the maximum efficiency compared to stainless steel and aluminum. The biofilm attached to the electrode is electrochemically active as per the redox potential shown in cyclic voltammogram results.

Determination of in vitro isoflavone degradation in rumen fluid

The aim of this study was to determine the degradation of dietary isoflavones in rumen fluid under 2 feeding regimens. The experiments were performed in vitro using a rumen fluid buffer system. The rumen fluid was taken from cows fed either a hay diet or a concentrate-rich diet (the diet consisted of 34.6% maize silage, 17.6% haylage, 12.8% alfalfa hay, and 35.0% supplemental mixture on a dry matter basis). As a source of isoflavones, 40% soybean extract (Biomedica, Prague, Czech Republic) at levels of 5, 25, 50, and 75 mg per 40 mL of rumen fluid was used. Samples of soybean extract were incubated in triplicate at 39°C for 0, 3.0, 6.0, 12.0, and 24.0 h in incubation solution. The metabolism of daidzein and genistein was faster under concentrate-rich diet conditions. In general, production of equol started after 3 to 6 h of incubation and reached the highest rate after approximately 12 h of incubation regardless of the type of diet or concentration of extract. In most of the experiments, production of equol continued after 24 h of incubation. Generally, equol production was greater under the hay diet conditions. Furthermore, experiments with higher amounts of added soybean extract revealed possible inhibitory effects of high levels of isoflavones on the rumen microflora.