VFA Concentration Research Articles

Fast Protein and Metabolites (Nucleotides and Nucleosides) Liquid Chromatography Technique and Chemical Sensor for the Assessment of Fish and Meat Freshness

Fast protein and metabolite liquid chromatography (FPLMC) was introduced years ago to enable the easy separation of high-molecular compounds such as proteins from small molecules and the identification of the low-molecular substances. In this paper, the method is applied for the rapid evaluation of freshness and monitoring the aging of animal meat and fish. A novel chromatographic sensor was developed with a deep UV LED-based photometric detection unit (255–265 nm), an original flow cuvette and registration scheme; the processing of a chromatogram with the sensor takes approximately 15 min. Strict isochronism between the elution of ATP metabolites, mainly hypoxanthine (Hx) and inosine monophosphate (IMP), and the time of maturation of meat or fish, was discovered. A new freshness index H* = [Hx]/[IMP] was introduced, which is proportional to the instrumental delay time in the FPMLC chromatograms: the H* index < 0.5 indicates the presence of inosine monophosphate (IMP) and the high quality of the meat or fish. Reasonably strong correlations were revealed between data obtained by FPMLC and total volatile basic nitrogen TVB-N (for fish) or volatile fatty acids VFA (for meat) content. Moreover, putative nucleotide salvage and an increase in the concentration of IMP were observed in fish after heat treatment using the FPMLC sensor and NMR technique.

GPR120 Gene expression and activity in subcutaneous and intramuscular adipose tissues of Angus crossbred steers.

We hypothesized that media long-chain fatty acids (LCFA) would more greatly depress cyclic adenosine monophosphate (cAMP), glycerol, and free fatty acid (FFA) concentrations in subcutaneous (s.c.) adipose tissue than in intramuscular (i.m.) adipose tissue via G protein-coupled receptor 120 (GPR120). The GPR120 receptor binds to LCFA, which reduces cAMP production, thereby causing a depression in lipolysis. Fresh ex vivo explants of s.c. and i.m. adipose tissue from the fifth to eighth longissimus thoracic rib muscle section of 8, 22-mo-old Angus crossbred steers were transferred immediately to 6-well culture plates containing 3 mL of Krebs-Henseleit buffer/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (volatile fatty acids, VFA) (0, 1, 5, and 10 mM) in the absence or presence of 100 µM oleate (18:1n-9) or 100 μM palmitate (16:0) (LCFA) were added to the incubation media and incubated an additional 30 min. Main effects of adipose tissue depot (i.m. vs. s.c) and VFA (acetate vs. propionate) for adipose tissue concentrations of forskolin-stimulated cAMP were P = 0.747 and P = 0.106, respectively. The addition of LCFA to the media depressed adipose tissue concentrations of cAMP (P = 0.006) (LCFA main effects). The Tissue × VFA × LCFA interaction was not significant for any dependent variable (P ≥ 0.872). Therefore, concentrations of cAMP, glycerol, and FFA were analyzed separately for i.m. and s.c. adipose tissue by split-plot analysis. Concentrations of cAMP, glycerol, or FFA in i.m. and s.c. adipose tissue were not affected by increasing concentrations of VFA (P ≥ 0.497). Media LCFA had no effect on i.m. adipose tissue cAMP (P = 0.570) or glycerol (P = 0.470) but depressed i.m. adipose tissue FFA (P < 0.001). In s.c. adipose tissue, LCFA decreased concentrations of cAMP (P = 0.042) and glycerol (P = 0.038), but increased FFA concentration (P = 0.026). Expression of GPR120 (P = 0.804) and stearoyl-CoA desaturase (P = 0.538) was not different between s.c. adipose tissue and i.m. adipose tissue. The binding of VFA to the GPR43 receptor depresses cAMP production, thereby attenuating lipolysis, but GPR43 mRNA was undetectable in those adipose tissue samples. These results provide evidence for functional GPR120 receptors in s.c. adipose tissue but question the role of GPR43 in the accumulation of adipose tissue lipids in growing steers.

Effects of adding ruminal propionate on dry matter intake and glucose metabolism in steers fed a finishing ration.

The objective of this experiment was to determine if supplying additional propionate to the rumen alters dry matter intake (DMI), feeding behavior, glucose metabolism, and rumen fluid metabolites in steers fed a finishing diet. Ruminally cannulated steers (n = 6) were fed a finishing diet ad libitum. Steers were randomly assigned to one of three treatments in a 3 × 6 Latin rectangle design with three 15 d periods. Treatments of no Ca propionate (Control), 100 g/d (Low), or 300 g/d (High) were ruminally dosed twice daily. Individual intake was measured using an Insentec feeding system. Pre-feeding blood samples were collected on day 7 and rumen fluid samples were collected on day 13. An intravenous glucose tolerance test (IVGTT) was conducted on day 14 and liver biopsies were collected on day 15. Liver samples were analyzed for expression of genes involved in gluconeogenesis. Data were analyzed using a mixed model with period, treatment, day, and their interaction included, with day and minute within period as a repeated measure and steer as a random effect. Meal size (P = 0.049), meal frequency (P = 0.046), and DMI (P < 0.001) were decreased in High steers. Day 7 plasma glucose (P = 0.23) and lactate (P = 0.47) were not affected by treatment, but insulin was decreased (P = 0.008) and non-esterified fatty acids were increased (P = 0.044) in the High treatment compared with the Control. Rumen fluid lactate was decreased (P = 0.015) in the High treatment compared with the Low treatment. Total VFA concentrations did not differ (P = 0.88) between treatments. There was treatment × time interaction for proportions of acetate and propionate (P < 0.001) and the acetate:propionate ratio (P = 0.005). The effect on acetate was due to a decrease in the High treatment 2 h after dosing the treatment. Propionate proportions were greater in the High treatment than the Control at all time points and differed from the Low except at 0 h. Propionate treatments had no major effects on the glucose and insulin parameters observed in the IVGTT other than a tendency (P = 0.09) for an increased insulin time to peak. These data indicate that exogenous propionate decreases DMI but the decrease in propionate from fermentation due to reduced DMI might negate the supply of exogenous propionate in VFA supply to the animal. Mechanisms other than hepatic oxidation of propionate might be responsible for DMI regulation.

Dark fermentation of pretreated hydrolysates of pineapple fruit waste for the production of biohydrogen using bacteria isolated from wastewater sources

ABSTRACT In the present study, both acidic and alkaline hydrolysate of pineapple waste was utilised for the production of biohydrogen using locally isolated bacterial strains. The bacteria were isolated from different wastewater sources and were identified as Proteus mirabilis, Pseudomonas aeruginosa, Bacillus altitudinus, Bacillus subtilis, Paenibacillus alvei, and Lysinibacillus sphaericus. Experimental results showed that the highest biohydrogen yield of 836.33 ± 48.02 mL H2 was produced from alkaline hydrolysate with Bacillus altitudinis during the 96thhr of fermentation. Among the different bacterial strains, B. altitudinis showed higher H2 production. Comparatively alkaline hydrolysates exhibited a higher yield of hydrogen than acidic hydrolysates. The final pH of the experiment was found to be in acidic range. The total VFA concentration ranged between 930 ± 207.85 mg/L to 3050 ± 476.97 mg/L. Both sugar degradation and COD reduction were more than 80% in the acidic and alkaline hydrolysates while the lowest sugar degradation and COD reduction were observed for the untreated biomass. The rationale behind this study was to convert the waste biomass into energy by utilising the potential of native bacterial communities.

Effect of inclusion of distillers grains with solubles and crude glycerin in beef cattle finishing diets on ruminal fermentation and fatty acid biohydrogenation.

An experiment was conducted to evaluate the impact of feeding bio-fuel co-products on ruminal fermentation characteristics and composition of omasal digesta flow. Four ruminally cannulated Holstein steers (371 ± 5 kg) were used in a 4 × 4 Latin Square design. Omasal sample collection and triple marker technique was used to quantify fatty acid omasal flow. Treatments were applied as a 2 × 2 factorial where a steam flaked corn (SFC) basal diet (DGS-N CG-N) was replaced with 40% of diet DM as corn distillers grains (DGS; DGS-Y CG-N) or 10% of diet DM as crude glycerin (DGS-N CG-Y) or 40% of diet DM distillers grains and 10% of diet DM as crude glycerin (DGS-Y CG-Y). No effects were observed for the interaction of DGS and glycerin on measured rumen characteristics. Dietary inclusion of glycerin decreased (P = 0.05) ruminal content 4-h post feeding on a DM basis but did not influence DMI (P = 0.64). Feeding DGS had no effect (P = 0.34) on particulate passage to the omasum (kg/d) in spite of greater (P = 0.04) DMI. Feeding DGS reduced flow rate (% of rumen volume/h) (P = 0.05) but did not affect total VFA concentration (P = 0.46) or average ruminal pH (P = 0.72). No differences (P > 0.05) were observed in ruminal parameters when feeding glycerin, besides ruminal particulate content (kg) on DM basis (P = 0.05). An interaction of DGS and glycerin affected intake of stearic (P < 0.01), linoleic (P < 0.01), and linolenic acid (P < 0.01). An interaction of DGS and glycerin did not affect individual fatty acid flow with respect to intake for stearic (P = 0.17), linoleic (P = 0.18), or linolenic acid (P = 0.66). Dietary inclusion of glycerin had no impact on g of linolenic (P = 0.16) or linoleic (P = 0.32) acid transformed. A trend was identified for cattle fed diets with glycerin to have increased (P = 0.07) grams of conjugated linoleic acid (CLA; C18:2 cis-9, trans-11) per gram of linoleic acid intake, with no impact on the percent of saturated fat (P = 0.44) or unsaturated fat (P = 0.43) in omasal flow. For cattle fed diets with DGS, fewer grams of linoleic (P < 0.01) and linolenic (P < 0.01) were present in digesta flow per gram of intake. Inclusion of DGS in the treatment diets also increased (P < 0.01) stearic acid flow (g) and CLA flow (g) per gram of stearic and linoleic acid intake, respectively. Observed differences in CLA proportion post fermentation may indicate interrupted biohydrogenation when glycerin is fed.

Polyunsaturated fatty acids and rumen undegradable protein alter ruminal fermentation and milk fatty acid profiles in dairy cows

ABSTRACT The present study evaluated the effects of incorporating polyunsaturated fatty acid (PUFA)- and rumen undegradable protein (RUP)-enriched feeds on ruminal fermentation, methane production, milk yield and milk FA profiles in dairy cows. Experiment 1 was carried out on 12 multiparous HF dairy cows in mid-lactation (106 ± 18.6 days in milk, 13.1 ± 1.67 kg/d of milk). Environmental conditions throughout the experiment were 34.5 ± 1.9 8°C, 58.0 ± 2.65% relative humidity and 85.7 ± 2.71 temperature–humidity index. Cows (n = 6/group) were randomly allocated to a control diet (Ctrl) consisting of corn silage and concentrate (F:C 60:40) containing 27.2% RUP in the crude protein (CP) or a treatment diet (Trt) consisting of 58.3% corn silage, 29.6% concentrate, 3.24% roasted soybean meal, 5.82% corn dried distiller grains with solubles and 3% added oil, which contained linseed, sunflower and tuna crude oil (1:1:1, wt/wt). The Trt diet contained 35.0% RUP in the CP. Experiment 2 was conducted in vitro using ruminal fluid collected from three Holstein Friesian dairy cows. The experimental design and diets were the same as in Exp. 1. Dry matter intake (DMI) tended to be lower (P = 0.06) in the Trt group. No difference in milk yield was detected, but the lower (P < 0.01) milk fat was measured in the Trt group (2.82% vs. 3.81%). Feed efficiency (milk/DMI) tended to be greater (P = 0.06) in the Trt cows (1.08 vs. 0.88). Lower 18:0 (5.73% vs. 8.29%), but greater concentrations of c9,t11 CLA (1.88% vs. 0.34%), c9,c12 18:2 (1.55% and 0.69%) 18:3n-3 (0.30% vs. 0.12%) and 22:6n-3 (0.17% vs. 0%) were detected in milk fat of cows fed Trt (P < 0.01). Atherogenicity and thrombogenic indices were lower (P < 0.01) with Trt. Concentrations of ruminal total volatile fatty acids and methane, which was assessed by production of volatile fatty acids, were 10.2% and 11.7% lower P < 0.01) in the Trt group. In conclusion, incorporating PUFA- and RUP-high feeds in lactating cow diets in the tropics causes a reduction in concentrations of ruminal VFA, methane production and milk fat while improving aspects of milk quality without affecting milk production.

К вопросу управления физиологическими процессами и формированием сбалансированного микробиома в рубце коров и овец путем введения в рацион кормовых факторов с определенными биологическими и функциональными свойствами

In physiological and production studies on intact and fistulated cows and sheep, the effect on enzymatic and microbiological processes in the rumen was studied when energy feed (EF) based on propylene glycol, glycerin and sugars was included in the standard diet of cows, separately and in combination with a complex of cellulolytic enzymes, consisting from cellulase, glucoaminolase, xylanase and β-gluconase (EF + CCE), and in the standard diet of sheep – micellate-Ca (M-Ca), microalgae Spirulina Platensis (Sp.Pl.), dihydroquercetin (DHQ) separately and in combination with organic iodine (DHQ+OJ). As a result of the use of these feed factors, there were changes in the indicators of digestion in the rumen of cows and sheep. In cows under the influence of EF in the rumen chyme, in relation to the control, cellulolytic activity increased by 75,4 %, and amylolytic activity decreased by 17,0 %, the content of VFA increased by 3,9 % and acetate by 2,2 %, and the content of propionate, butyrate and ammonia decreased by 5,6; 6,2 and 3,3 %, respectively. At the same time, there was an increase in the number of bacteria by 6,2 % and ciliates by 2,6 %, with a stable pH of 6,8. The inclusion of EF + CCE in the diet of cows did not affect the pH of the chyme, equal to 7,2; increased the content of VFAs by 3,6 % and reduced the content of ammonia by 3,8 % had almost no effect on the number of microorganisms, but changed its composition – the number of bacteria increased by 27,8 %, and the number of ciliates decreased by 23,5 %. In sheep, under the influence of M-Ca in the chyme, there was an increase in pH from 6,31 to 6,54, the content of VFAs by 6,6 %, amylolytic activity by 1,7 %, the number of microorganisms by 1,4 %, incl. ciliates by 0,4 %, bacteria by 2,2 % and the ammonia content decreased by 16,4 %. under the influence of Sp.Pl. there was an increase in pH from 6,31 to 6,91, amylolytic activity by 6,1 %, and a decrease in the content of VFAs by 18,2 %, ammonia by 3,4 %, the number of microorganisms by 5,4 %, incl. ciliates by 19,2 % and bacteria by 8,4 %; under the influence of DHQ, there was an increase in pH from 5,7 to 6,4, a decrease in the content of VFAs by 18,9 %, amylolytic activity by 7,3 %, ammonia by 24,1 %, an increase in the number of microorganisms by 2,2 % incl. h bacteria by 26,5 % with a decrease in the number of ciliates by 27,3 %; under the influence of DHQ + OJ, there was an increase in pH from 5,7 to 5,8, amylolytic activity by 1,1 %, ammonia content by 16.5 %, the number of microorganisms by 15,3 %, incl. ciliates by 56,1 % and bacteria by 8,7 %. All feed factors, with the exception of DHQ+OJ, shifted the redox potential of the chyme towards reduction, and under the action of DHQ+OJ, towards oxidation.

Impact of Mangrove Leaves (Rhizophora apiculata) in Limewater on Nutrients Digestibility, Rumen Ecosystem and in vitro Methane Production

The Mangrove is one of the plants that live in coastal areas, because a lot of their availability, mangrove leaves can be used as animal feed. The problem with this mangrove is contained a fairly high tannin which can be harmful to livestock. This study aims to determine the impact of boiled mangrove leaves (Rhizophora apiculata) with lime water on tannins, digestibility, rumen characteristics, and in vitro methane production. The design used in this study was a randomized block design using 4 treatments and 5 replications. The treatments were boiled with the respective concentrations of quicklime water as follows, P1 (without boiling), P2 (5% lime water), P3 (10% lime water), and P4 (15% lime water) for 10 min. The results showed that boiling mangrove leaves with 5% lime water showed highly significant (p<0.01) results on total tannins content, nutrient digestibility, rumen fluid characteristics, and reduced methane gas content. Nutrient digestibility includes among others: Dry matter digestibility (65.18%), organic matter digestibility (66.31%), crude protein digestibility (67.90%), and increased digestibility of fiber fractions including NDF digestibility (59.01%), ADF digestibility (55.75%), cellulose digestibility (64.02%), hemicellulose digestibility (69.61%) and increased rumen fluid characteristics such as NH3 contents (4.32 Mg/100 mL) and VFA content (130.2 mm) and Methane gas (231.39 mL/gDM). The results of this study concluded that boiling mangrove leaves in lime water at a concentration of 5% for 10 min contributed to the most prominent total tannins (4.54%) and digestibility of nutrients.

Populasi Mikroba Rumen, Fermentabilitas, dan Kecernaan Suplementasi Daun Kelor dalam Ransum Sapi Perah secara In Vitro

This study aimed to evaluate the microbial rumen population, fermentability, and digestibility of Moringa leaf supplementation in dairy cow ration using in vitro and to determine the optimal level of supplementation. The experiment consist of two steps with the first step was microbiology measurement used a Randomized Block Design with 5 treatments level of Moringa leaf extract (P0= control; P1= 5%, P2 = 10%, P3 =15%, P4 =20%) and the second step was in vitro fermentability and digestibility measurement used Randomized Block Design with 7 treatments level of Moringa leaf in dairy cow ration (R0 = control, R1 = R0 + 2.5% Moringa leaf, R2= R0 +5% Moringa leaf, R3 = R0 + 7.5% Moringa leaf, R4= R0+10% Moringa leaf, R5=R0+12.5% Moringa leaf, R6=R0+15% Moringa leaf) which grouped by rumen fluids. Data analysis used analysis of variance and continued with Duncan’s Multiple Range Test. The measured variable were microbial rumen population (bacteria and protozoa), fermentability (N-NH3, VFA), microbial protein synthesis, dry matter digestibility (DMD), and organic matter digestibility (DMO). The results showed Moringa leaf extract significantly decreased bacterial population (p&lt;0.05), but there was no effect on the protozoa population. Moringa leaf supplementation did not affect N-NH3, DMD, and DMO, but significantly influenced VFA concentration and microbial protein synthesis (p&lt;0.01). The higher Moringa leaf supplementation showed decreasing total VFA concentration, but was still within the normal range for rumen fermentation (102.29-126.69 mM). Moringa leaf supplementation showed a quadratic effect on microbial protein synthesis with an optimal supplementation level of 5%, but decreasing at a level of 7.5% still within in normal range. It can be concluded Moringa leaf can be supplemented up to 7.5% in dairy cow ration.&#x0D; Key words: digestibility, fermentability, in vitro, moringa leaf, dairy cow

PENGARUH PEMBERIAN HASIL FERMENTASI EKSTRAK BUAH LONTAR DAN FESES AYAM DALAM KONSENTRAT TERHADAP PEMANFAATAN ENERGI PADA TERNAK KAMBING (Effect of fermented palm fruits extract and chicken manure in concentrate on energy utilisation in goats)

This study aimed to investigate the effect of feeding palm fruit extrack and chicken manure on energy utilisation in goats. This study used a Latin Square Design with four treatments and four periods of data collection as replications. The four treatments were: BP (Botriochloa pertusa hay 40% + Leucaena leucocephala 30% + concentrate 30%), BPS (Botriochloa pertusa hay 40% + Leucaena leucocephala 30% + concentrate 20% + palm fruit extract 10%), BPFA (Botriochloa pertusa hay 40% +Leucaena leucocephala 30% + concentrate 20% + chicken feces 10%), BPSFA (Botriochloa pertusa hay 40% + Leucaena leucocephala 30% + concentrate 20% + palm fruit extract 5% + chicken feces 5%). The parameters measured consisted of the intake and digestibility of crude fiber, VFA concentration, and blood glucose levels. The result showed that feeding fermented of palm fruits extract at different levels in the concentrate have no significant effect (P&gt;0.05) on the intake and digestation of crude fiber and the concentration of blood glucose. However, it had a significant effect (P&lt;0.01) on the total VFA concentration. In conclusion, feeding fermented concentrate containing palm fruit extract and chicken feces increases the total VFA concentration but it does not increase the intake and digestation of crude fiber and the concentation of blood glucose in male goats.

CaCO3 solubility in the process water of recycled containerboard mills

Abstract Water system closure in recycled containerboard mills may have reached a technical limit due to the accumulation of organic and inorganic contaminants in the process water. The specific water chemistry characteristics of recycled containerboard mills with restricted water systems were analyzed and a computer model was developed to simulate calcium carbonate solubility in the presence of volatile fatty acids under relevant mill conditions. A strong linear correlation between VFAs and calcium ions was found. The calcium carbonate dissolution mechanism, solubility, and precipitation were investigated. The reaction of VFAs with calcium carbonate results in the formation of bicarbonate and carbonic acid. By binding hydrogen ions, the carbonate has a pH buffering effect. The carbonic acid dissociates into water and CO2. Gaseous CO2 escapes from the water and leads to decarbonization. This mechanism is responsible for the uncoupling of pH from the concentration of VFAs, as well as from the concentration of dissolved calcium ions. The resulting lack of carbonates prevents the precipitation of calcium carbonate. The introduction of CO2 contained in the biogas produced in anaerobic biological water treatment reverses the dissolution mechanism and causes the precipitation of calcium carbonate. Concentrating technologies such as membrane filtration and evaporation may therefore meet the specific requirements for complete water system closure in recycled containerboard mills better than current commonly used biological treatment.

Effects of the chromium content on anaerobic fermentation of chrome shaving collagen and rice straw juice.

This thesis investigated the effects of different chromium contents on the gas production characteristics of anaerobic fermentation by mixing the collagen solution obtained from the hydrolysis of chromium tannin chips by alkali-enzyme combination with rice stalk hydrolysate and the changes of system pH, VFA concentration, SCOD concentration, ammonia nitrogen concentration, and chromium concentration during anaerobic fermentation. The experimental results show that the highest total gas production and cumulative methane production are 1531.0mL/gVS and 761.2mL/gVS, respectively, with a Cr content of 5mg/L, and the methane content reaches 49.7%. The best SCOD removal rate is 54.54% at a C/N ratio of 20:1. The increase in SCOD concentration is decreased with increasing chromium content, but there is no significant change in ammonia nitrogen concentration. The highest rate of SCOD degradation is achieved with a chromium content of 5mg/L. The results of this thesis provide data support and theoretical guidance for the resource recovery of chromium leather shavings.

Long-term inhibition of chlortetracycline antibiotics on anaerobic digestion of swine manure

This study aimed to identify whether chronic effects are present in the anaerobic digestion (AD) of swine manure (SM) containing chlortetracycline (CTC), which is one of the major broad-spectrum veterinary antibiotics, and to elucidate the long-term inhibitory effects and recovery from the inhibition based on AD performance and microbial community. Two continuous-stirred tank reactors treating SM with and without CTC spiking (3 mg/L) were operated for 900 days. Due to the degradation and transformation, the total concentration including CTC's epimer and isomer in the test reactor was 1.5 mg/L. The exposure level was determined according to probabilistically estimated concentrations with uncertainties in field conditions. Until the cessation of CTC exposure on day 585, the methane generation of test reactor continuously decreased to 55 ± 17 mL/g-VS/day, 53% that of control. The methane generation and organic removal were not recovered within 300 days after the CTC exposure was stopped. During the experiment, stability parameters such as pH, total ammonium nitrogen, the composition of methane and alkalinity were the same for both reactors. The concentration and composition of VFAs in the test reactor were different with those of control but not in inhibition level. Microbial profiles revealed that reduction in bacterial diversity and changed balance in microbial species resulted in the performance downgrade under the long-term antibiotic pressure. Since it is hard to recover from the inhibition and difficult to predict the inhibition using physicochemical indicators, continuous exposure to CTC needs to be avoided for the sustainable management of AD plants treating SM.

Community succession and functional prediction of microbial consortium with straw degradation during subculture at low temperature

To systematically explore and analyze the microbial composition and function of microbial consortium M44 with straw degradation in the process of subculture at low temperature. In this study, straw degradation characteristics of samples in different culture stages were determined. MiSeq high-throughput sequencing technology was used to analyze the evolution of community structure and its relationship with degradation characteristics of microbial consortium in different culture periods, and the PICRUSt function prediction analysis was performed. The results showed that straw degradation rate, endoglucanase activity, and filter paper enzyme activity of M44 generally decreased with increasing culture algebra. The activities of xylanase, laccase, and lignin peroxidase, as well as VFA content, showing a single-peak curve change with first an increase and then decrease. In the process of subculture, Proteobacteria, Bacteroidetes, and Firmicutes were dominant in different culture stages. Pseudomonas, Flavobacterium, Devosia, Brevundimonas, Trichococcus, Acinetobacter, Dysgonomonas, and Rhizobium were functional bacteria in different culture stages. It was found by PICRUSt function prediction that the functions were concentrated in amino acid transport and metabolism, carbohydrate transship and metabolism related genes, which may contain a large number of fibers and lignin degrading enzyme genes. In this study, the microbial community succession and the gene function in different culture periods were clarified and provide a theoretical basis for screening and rational utilization of microbial consortia.

Cactus Cladodes Opuntia or Nopalea and By-Product of Low Nutritional Value as Solutions to Forage Shortages in Semiarid Areas.

We aimed to evaluate the effect of the cactus cladodes Nopalea cochenillifera (L). Salm-Dyck. (NUB) and cactus cladodes Opuntia&amp;nbsp;stricta (Haw.) Haw. (OUB), both combined with sugarcane bagasse (SB) plus urea, Tifton hay (TH), corn silage (CS), and sorghum silage (SS) plus urea on nutrient intake and digestibility, ruminal dynamics, and parameters. Five male sheep, fistulated in the rumen, were assigned in a 5 × 5 Latin square design. The NUB provided a higher intake of dry matter (DM) and any nutrients than SS. TH provided larger pools of DM and iNDF. The OUB and CS provided a higher DM degradation. CS provided a higher NDF degradation rate. OUB provided a lower ruminal pH. Depending on the collection time, the lowest pH value was estimated at 3.79 h after the morning feeding. There was an interaction between treatments and collection time on VFA concentrations. Due to the high degradation rate, greater energy intake, less change in rumen pH, greater volatile fatty acid production, and feasibility, we recommend using cactus associated with sugarcane bagasse plus urea in sheep diets.

Propionibacteriaium acidipropionici CP 88 Dose Alters In Vivo and In Vitro Ruminal Fermentation Characteristics

Twelve 5-year-old beef steers, with an average weight of 2000 lbs., fitted with rumen canulae were used in a 4 × 4 incomplete Latin square design to examine the impact of the direct fed microbial Propionibacterium acidipropionici CP 88 (PA) on rumen fermentation characteristics, in vitro CH4, CO2, and N2 production, and in vivo CH4 and CO2 production. All steers were housed in the same pen equipped with eight GrowSafe feeding stations to monitor individual animal feed intake and one GreenFeed System to estimate individual animal CH4 and CO2 production. Steers were fed a corn-silage-based diet throughout the experiment. Treatments consisted of PA administered at: (1) control (0.0); (2) 1.0 × 108; (3) 1.0 × 109; and (4) 1.0 × 1010 cfu∙animal−1∙day (d)−1. Treatments were administered directly into the rumen as a single bolus dose daily. On day 7 and 14 of each period, rumen fluid was collected from each steer 2 h post treatment administration for VFA analysis and in vitro DM digestibility determination. Following a 14 d washout period, animal treatments were switched and the experiment repeated until the 4 × 4 Latin square was complete. In vivo propionic acid molar proportions and total VFA concentrations were greater (p &lt; 0.05) in steers receiving PA when compared with controls. All other in vivo rumen fermentation characteristics were similar across treatments. In vitro DM disappearance (p &lt; 0.05) and total VFA (p &lt; 0.05) were greater and CH4 lesser (p &lt; 0.04) in fermentation vessels incubated with rumen fluid from animals receiving PA when compared with controls. Dry matter disappearance (p &lt; 0.03) and propionic acid molar proportions increased (p &lt; 0.04) linearly as the dose of PA increased. In vitro total VFA tended (p &lt; 0.08) to increase linearly and CH4 production per unit of DM digested tended (p &lt; 0.09) to decrease quadratically in response to PA dose. All other in vitro rumen fermentation characteristics were similar across treatments. These data indicate that PA impacts in vivo and in vitro rumen fermentation characteristics.

Understanding variability and repeatability of enteric methane production in feedlot cattle

Breeding ruminants for low methane (CH4) emissions can be permanent and cumulative, but requires a better understanding of the variability of CH4 production among animals to accurately assess low-CH4 phenotypes. Our objectives were to: 1) investigate the variation in CH4 production among and within growing beef cattle, 2) identify low-CH4 emitters, and 3) examine relationships between CH4 production and intake, feeding behavior, growth, and rumen fermentation. Crossbred beef heifers (n=77; body weight=450 kg) were allocated to 3 pens and offered a finishing diet of 90% concentrate and 10% silage (dry matter (DM) basis). The study was conducted over 3 consecutive 6-week periods (126 days). GrowSafe bunks measured individual animal DM intake (DMI) and rumen fluid was sampled orally each period. A GreenFeed system measured individual animal emissions for 2 weeks/period. Methane production was calculated by animal within period using visits that were ≥3 min with fluxes compiled into six 4-h blocks corresponding to time of day, and averaged over blocks to obtain an average daily emission for the period. Animals with &amp;lt;12 visits and &amp;lt;5 blocks were omitted for the period and animals with ≥2 periods of complete CH4 data were used in the final analysis (n=52). Animals were ranked based on CH4 yield (g/kg DMI) from low to high, and grouped as Very-low (≤10% of animals), Low (11-25%), Intermediate (26-74%), High (75-89%), and Very high (≥90%) emitters (mean ± SD, 12.6 ± 2.16). The CH4 yield was 16% less (P&amp;lt;0.05) for Very-low compared with Intermediate animals due to lower CH4 production (g/d, P&amp;lt;0.05), with no differences in DMI (P&amp;gt;0.05). However, the period × grouping interaction (P&amp;lt;0.001) for CH4 yield indicated that the ranking of animals changed over time, although there were no extreme changes in rankings. Total VFA concentration decreased as CH4 yield decreased, but molar proportions of VFA remained unchanged, suggesting lower extent of ruminal digestion rather than a shift in fermentation. There were no differences in feeding behavior or average daily gain among groupings (P&amp;gt;0.05). The between-animal coefficient of variation in CH4 yield of 17.3% enabled identification of low CH4-emmitting finishing beef cattle. However, accurate selection of low CH4-emitting animals should be based on repeated CH4 measurements over the production cycle.

An integrated leachate bed reactor – anaerobic membrane bioreactor system (LBR-AnMBR) for food waste stabilization and biogas recovery

This study developed an integrated LBR – AnMBR system for efficient stabilization and biogas recovery from food waste (FW) at room temperatures (21–22 °C). First, the leachate recirculation rate (4.4–13.2 L/h) was optimized to maximize hydrolysis and acidification yields. The maximum hydrolysis yield of 551 gSCOD/kg VSadded was achieved at recirculation rate of 13.2 L/h. The VFA concentrations in the FW leachate was as high as 12.5–16.0 g/L, resulting in a high acidification of 468 g CODVFA/kg VS. The solubilized FW was further stabilized by feeding the leachate to AnMBR. Different hydraulic (HRT) and solids retention times (SRT) were tested to achieve high COD removal and methane yields. High COD removal of 86 ± 3% was obtained in the AnMBR at HRT of 13 and SRT of 75 days. High biogas recovery of about 850 kWh per ton FWtreated was achieved along with high quality of AnMBR permeates containing low COD concentration but advantageously high concentration of nutrients (NH4+-N 317–403 mg/L, total phosphate 23–213 mg/L) without any particulates, which can be reused for landscape or liquid fertilizer.

Susceptibility of dairy cows to subacute ruminal acidosis is reflected in both prepartum and postpartum bacteria as well as odd- and branched-chain fatty acids in feces

BackgroundThe transition period is a challenging period for high-producing dairy cattle. Cows in early lactation are considered as a group at risk of subacute ruminal acidosis (SARA). Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH, dry matter content, volatile and odd- and branched-chain fatty acids (VFA and OBCFA, respectively), as well as fecal microbiota. This was investigated with 38 periparturient dairy cows, which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6. Furthermore, we investigated whether fecal differences were already obvious during a period prior to the SARA risk (prepartum).ResultsVariation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration. In the postpartum period, the copy number of fecal bacteria and methanogens of unsusceptible (UN) cows was higher than moderately susceptible (MS) or susceptible (SU) cows, while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows. Nevertheless, only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows, particularly iso-C15:0 and iso-C16:0, compared with UN cows. Consistent with the bacterial changes postpartum, the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows, whereas Lachnospiraceae_UCG-001 was increased. Nevertheless, no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups. Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70% of the SU cows belonging to cluster 1, in which they represented 60% of the animals.ConclusionsInter-animal variation in postpartum SARA susceptibility was reflected in post- and prepartum fecal bacterial communities. Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum. Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy.Graphical abstract

Effects of Sugar Beet Silage, High-Moisture Corn, and Corn Silage Feed Supplementation on the Performance of Dairy Cows with Restricted Daily Access to Pasture.

Simple SummarySeasonal variations in herbage growth rate and nutrient composition result in low herbage intake which is insufficient to meet the nutritional requirements of cows and limits milk production. The main opportunities for increasing milk production per cow and per ha are a careful pasture management to ensure adequate herbage high-quality and strategic low-cost and high-energy feed supplementation. Supplementation strategies include different combinations of level, type, and processing of supplemental feeds. This study evaluates the effect of supplementation with sugar beet silage, corn silage, or high-moisture corn (HMC) on dairy performance, rumen, and plasma metabolites in dairy cows under conditions of restricted grazing in spring. We found that the supplementation with sugar beet silage allowed milk production, live weight, and fat concentration similar to corn silage and HMC, but with a lower concentration of milk protein than HMC. Results suggest that sugar beet silage can be used as an alternative supplement for high-producing dairy cows under conditions of restricted grazing in the current experiment.A study was undertaken to assess the effect of supplementation with sugar beet silage, corn silage, or high-moisture corn on dairy performance, rumen, and plasma metabolites in dairy cows under conditions of restricted grazing in spring. Eighteen multiparous Holstein Friesian cows, stratified for milk yield (39.4 kg/day ± 3.00), days of lactation (67.0 days ± 22.5), live weight (584 kg ± 38.0), and number of calves (5.0 ± 1.5), were allocated in a replicated 3 × 3 Latin square design. Treatments were as follows: SBS (10 kg DM of permanent pasture, 7 kg DM of sugar beet silage, 4 kg DM of concentrate, 0.3 kg DM of pasture silage, 0.21 kg of mineral supplement); corn silage (10 kg DM of permanent pasture, 7 kg DM of corn silage, 4 kg DM of concentrate, 0.3 kg DM of pasture silage, 0.21 kg of mineral supplement), and HMC (10 kg DM of permanent pasture, 5 kg DM of high-moisture corn, 4.5 kg DM of concentrate, 1.2 kg DM of pasture silage, 0.21 kg of mineral supplement). Pasture was offered rotationally from 9 a.m. to 4 p.m. Between afternoon and morning milking, the cows were housed receiving a partial mixed ration and water ad libitum. The effect of treatments on milk production, milk composition, body weight, rumen function, and blood parameters were analyzed using a linear–mixed model. Pasture dry matter intake (DMI) was lower in SBS than CS (p < 0.05) and similar to HMC, but total DMI was higher in HMC than SBS (p < 0.05) and similar to CS. Milk production for treatments (32.6, 31.7, and 33.4 kg/cow/day for SBS, CS, and HMC, respectively), live weight, and fat concentration were not modified by treatments, but milk protein concentration was lower for SBS compared with HMC (p < 0.05) and similar to CS. B-hydroxybutyrate, cholesterol, and albumin were not different among treatments (p > 0.05), while urea was higher in SBS, medium in CS silage, and lower in HMC (p < 0.001). Ruminal pH and the total VFA concentrations were not modified by treatments (p > 0.05), which averaged 6.45 and 102.03 mmol/L, respectively. However, an interaction was observed for total VFA concentration between treatment and sampling time (p < 0.05), showing that HMC produced more VFA at 10:00 p.m. compared with the other treatments. To conclude, the supplementation with sugar beet silage allowed a milk response and composition similar to corn silage and HMC, but with a lower concentration of milk protein than HMC. In addition, sugar beet silage can be used as an alternative supplement for high-producing dairy cows with restricted access to grazing during spring.