Total Volatile Fatty Acids Research Articles

Integrating 16S rRNA Sequencing and LC-MS-Based Metabolomics to Evaluate the Effects of Dietary Crude Protein on Ruminal Morphology, Fermentation Parameter and Digestive Enzyme Activity in Tibetan Sheep.

The dietary crude protein level could affect ruminal fermentation parameters and the microflora of ruminants. The present study's aim was to investigate the effects of different protein level diets on ruminal morphology, fermentation parameters, digestive enzyme activity, microflora and metabolites of Tibetan sheep. Ninety weaned lambs (initial weight of 15.40 ± 0.81 kg, 2 months old) were selected and randomly divided into three groups (six pens/treatment, five rams/pen). Dietary treatments were formulated with 13.03% (high protein, HP), 11.58% (moderate protein, MP) and 10.20% (low protein, LP), respectively. Compared with LP, both papillae length and papillae width were significantly promoted in HP and MP (p < 0.05). The concentrations of ammonia nitrogen, total VFAs, propionic acids and butyric acids in HP were significantly increased compared to those in MP and LP (p < 0.05). The activities of protease and α-amylase in HP were significantly greater than those of LP (p < 0.05). For the ruminal microbial community, higher proportions of phylum Prevotella 1 and Succiniclasticum and genus Rikenellaceae RC9 gut group and Ruminococcus 1 were observed in HP (p < 0.05). A total of 60 differential metabolites (DMs) (28 up, 32 down) between HP and MP; 73 DMs (55 up, 18 down) between HP and LP; and 65 DMs (49 up, 16 down) between MP and LP were identified. Furthermore, four pathways of the biosynthesis of unsaturated fatty acids, tryptophan metabolism, bile secretion and ABC transporters were significantly different (p < 0.05). The abundance of phylum Prevotella 1 was negatively associated with stearic acid and palmitic acid but positively associated with the taurine. The abundance of genus Ruminococcus 1 was negatively associated with stearic acid, oleic acid, erucic acid, Indole-3-acetamide and palmitic acid but positively associated with 6-hydroxymelatonin. In conclusion, a 13.03% CP level improved ruminal morphology, fermentation parameters and digestive enzyme activities through modulating the microbial community and regulating metabolism in Tibetan sheep.

Effect of sodium lignosulfonate and propionic acid application rate on dry matter losses, nutritional composition, in vitro gas production, and fungal populations of high moisture alfalfa hay mini bales

This study evaluated the effects of application rate (AR) of sodium lignosulfonate (MBL) and propionic acid (PRP) on high moisture alfalfa hay spoilage during storage and its nutritive value. Treatments (TRT; MBL and PRP) were applied at four AR: 0 (CON), 2.5, 5 and 10 g/kg (fresh basis) to alfalfa hay at 68.5 % dry matter (DM), packed into mini bales and stored for 33 d. Data were analyzed as a randomized complete block design (5 blocks) with a 2 TRT × 4 AR factorial arrangement. At d 33, DM losses were decreased by PRP at 5 and 10 g/kg (x¯=0.9), vs. CON (6.92) and MBL (6.63 ± 1.13 %). Visual moldiness (0–10 ranking) and mold counts were also decreased by PRP at 5 (2.4 and 5.30) and 10 g/kg (0 and 2.7) relative to CON (6.0 and 7.13) and MBL (5.85 ± 0.67 and 7.21 ± 0.31 log cfu/fresh g, respectively). Both TRT kept aNDF and ADF concentrations low at 2.5 g/kg AR (464 and 319) and to a greater extent at 10 g/kg (442 and 307), relative to CON (494 ± 8.1 and 333 ± 4.71 g/kg DM, respectively; P<0.001). Both TRT increased apparent in vitro DM digestibility at all AR relative to CON (x¯=543 vs. 501 ± 12.0 g/kg of DM, respectively), but, compared to MBL, PRP also increased the asymptotic maximal gas produced (188.4 vs. 179.7 ± 4.82 mL/g of incubated DM), the rate of gas production (9.46 vs. 8.72 ± 0.45 %/h), and total volatile fatty acids (117.5 vs. 114.8 mM, respectively; P<0.035), due to its greater concentration of nutrients. In conclusion, MBL failed to prevent spoilage of high moisture alfalfa hay while PRP was effective at doses >5 g/kg. However, MBL prevented the increase of aNDF and improved in vitro DM digestibility to the same extent as PRP, possibly due to its strong surfactant properties.

Digestion, nitrogen excretion and rumen microbial communities in beef cattle, and in vitro methane output, of fresh temperate grass with or without citrus pulp supplementation

The effects of supplementing grass with a high-energy, low-protein concentrate on intake, rumen fermentation, rumen microbial communities, apparent total tract digestibility and N-balance in beef cattle, and rumen fermentation and methane output in vitro, were studied. Sixteen Charolais steers (mean live weight (s.d.) 564 (24.3) kg)), were used in a completely randomised block design experiment, and offered either zero-grazed perennial ryegrass (Lolium perenne L.) ad libitum (GO), or the same grass with 2.25 kg citrus pulp dry matter (DM) daily (GCP). During the measurement phase, DM intake was restricted at 0.85 of their pre-determined intake. The same diets were incubated in an eight-vessel RUSITEC system. Supplementation decreased grass DM intake (6.59 vs. 7.54 kg/d) but increased total DM intake by 0.95 kg/d (P < 0.01). Rumen pH (P = 0.05) and NH3 concentration (P < 0.05) decreased, and total volatile fatty acid (VFA) concentrations (P < 0.01), molar proportions of propionate (P = 0.08) and butyrate (P < 0.05) increased for GCP compared to GO. Supplementation significantly altered the overall rumen microbial community structure compared to GO, driven principally by changes in relative abundance of Prevotella, Methoanobrevibacter and Lachnospiraceae genera. Plasma urea concentration was lower (P < 0.05) for GCP than GO. There was no effect (P > 0.10) of supplementation on apparent total tract digestibility of DM, OM and ADFom, but aNDFom digestibility tended to be lower (P = 0.07) and crude protein (N × 6.25) digestibility was lower (P < 0.01) for GCP compared to GO. Nitrogen intake (200 g/d) did not differ (P > 0.05) between treatments. Faeces N loss was 9 g/d greater (P < 0.01), and urine (P < 0.01) and total (P < 0.05) N losses were 22 and 13 g/d lower, respectively, for GCP compared to GO. In terms of N-balance (g/kg N intake), faecal N excretion was greater and urinary N excretion was lower (P < 0.01) resulting in a greater N use efficiency (P = 0.06) for GCP than GO. In vitro rumen NH3 concentrations were lower (P < 0.01) for GCP compared to GO, whereas in vitro rumen pH, lactic acid, VFA concentrations and molar proportions, and methane and total gas output did not differ (P > 0.05) between treatments. Supplementing grass with a low-protein, high-energy feed may be a strategy to reduce urinary and total N excretion in beef cattle grazing temperate grass pasture.

Influence of dietary mulberry (Morus alba L.) leaf supplementation on production performance, blood metabolites, rumen fermentation characteristics and ruminal bacteria community in lactating dairy cows

The purpose of this study was to determine the effect of mulberry (Morus alba L.) leaf (ML) supplementation on the productivity, blood metabolism, rumen fermentation characteristics and rumen microbial population in lactating dairy cows. Twelve healthy multiparous Holstein dairy cows (initial characteristics: body weight = 442.83 ± 86.87 kg; milk yield = 12.55 ± 1.91 kg/d; days in milk = 150.0 ± 47.0 d) were randomly allocated to two treatment groups of six cows each. The cows were fed two different diets: a control diet (basal diet without ML; CTRL group) and a ML-supplemented diet (basal diet + 300 g ML; ML group). The trial lasted for a total of 28 d after an adjustment period of 14 d. The total rumen volatile fatty acid (VFA) levels (p = .063) and the propionate level (p < .05) were increased in the ML group, whereas the ratio of acetate to propionate was significantly decreased (p < .05). A microbiome study demonstrated that the dietary treatments significantly influenced the composition of rumen bacteria. The ruminal populations of Paludibacter propionicigenes, Ruminococcus sp. JE7A12 and Prevotella oris were greater (p < .05) in ML group than in CTRL group, while Enterococcus faecalis numbers significantly decreased (p < .05) in the ML group. Supplementing a dairy cow diet with 300 g ML has the potential to alter the microbial community and fermentation in the rumen, leading to an increase in propionate synthesis.

Sargassum mcclurei Mitigating Methane Emissions and Affecting Rumen Microbial Community in In Vitro Rumen Fermentation.

Methane emissions from ruminants significantly contribute to greenhouse gases. This study explores the methane mitigation effect and mechanism of S. mcclurei through in vitro rumen fermentation, aiming to establish its potential as a feed additive. We investigated the effects of freeze-dried and dried S. mcclurei at supplementation levels of 2%, 5%, and 10% of dry matter on nutrient degradation, ruminal fermentation, methane inhibition, and microbial community structure in in vitro rumen fermentation. The freeze-dried S. mcclurei at 2% supplementation significantly reduced CH4 emissions by 18.85% and enhanced crude protein degradability. However, total VFA and acetate concentrations were lower in both treatments compared to the control. The microbial shifts included a decrease in Lachnospiraceae_NK3A20_group and Ruminococcus and an increase in Selenomonas, Succinivibrio, and Saccharofermentans, promoting propionate production. Additionally, a significant reduction in Methanomicrobium was observed, indicating direct methane mitigation. Freeze-dried S. mcclurei at a 2% supplementation level shows potential as an effective methane mitigation strategy with minimal impact on rumen fermentation, supported by detailed insights into microbial community changes.

Effect of Guanidinoacetic Acid on Production Performance, Serum Biochemistry, Meat Quality and Rumen Fermentation in Hu Sheep.

Guanidinoacetic acid (GAA) can effectively improve the metabolism of energy and proteins by stimulating creatine biosynthesis. We present a study exploring the impact of GAA on production performance, serum biochemistry, meat quality and rumen fermentation in Hu sheep. A total of 144 weaned male Hu sheep (body weight 16.91 ± 3.1 kg) were randomly assigned to four groups with three replicates of twelve sheep in each group. The diets were supplemented with 0 (CON), 500 (GAA-1), 750 (GAA-2) and 1000 mg/kg (GAA-3) of GAA (weight of feed), respectively. After a comprehensive 90-day experimental period, we discovered that the supplementation of GAA had a remarkable impact on various muscle parameters. Specifically, it significantly enhanced the average daily growth (ADG) of the animals and improved the shear force and fiber diameter of the muscle, while also reducing the drip loss and muscle fiber density. Furthermore, the addition of GAA to the feed notably elevated the serum concentrations of high-density lipoprotein cholesterol (HDL-C), total protein (TP) and globulin (GLB), as well as the enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Concurrently, there was a decrease in the levels of triglycerides (TG) and malondialdehyde (MDA) in the serum. In addition, GAA decreased the pH and the acetate-to-propionate ratio and increased the total volatile fatty acids (TVFA) and ammoniacal nitrogen (NH3-N) levels of rumen fluid. Additionally, GAA upregulated acetyl-CoA carboxylase (ACC) gene expression in the Hu sheep's muscles. In conclusion, our findings suggest that GAA supplementation not only enhances muscle quality but also positively affects serum biochemistry and ruminal metabolism, making it a potential candidate for improving the overall health and performance of Hu sheep.

The Impact of Three White-Rot Fungi on Nutrient Availability, Greenhouse Gas Emissions, and Volatile Fatty Acid Production in Myceliated Sorghum.

Our study employed Pleurotus ostreatus, P. djamor, and Trametes versicolor (white rot fungi = WRF) in the process of solid-state fermentation (SSF) to convert sorghum grains into myceliated sorghum (MS). The MS was then used for in vitro studies to assess changes in nutrient content compared to untreated sorghum (control). The results demonstrated a significant (p < 0.001) increase in dry matter (DM), crude protein (CP), ash, neutral detergent fiber (NDF), and acid detergent fiber (ADF) contents of MS. Specifically, CP and ash values saw a remarkable increase from 68 to 330% and 40 to 190% in MS, respectively. Additionally, NDF and ADF degradability values increased significantly (p < 0.001) by 81.5% and 56.2% in P. djamor-treated MS at 24 h post-incubation. The treatment × time interaction was also significant (p < 0.001) for greenhouse gas (GHG) emissions. T. versicolor MS exhibited the highest total volatile fatty acid (TVFA) and propionate production. The use of WRF in the SSF process led to a significant improvement in the nutritional value of sorghum. Despite the varying effects of different WRF on the nutritional parameters in MS, they show potential for enhancing the feed value of sorghum in animal feed.

Integrated multi-omics reveals the relationship between growth performance, rumen microbes and metabolic status of Hu sheep with different residual feed intakes

Residual feed intake (RFI) is a metric that provides a more accurate measure of feed efficiency. The lower the RFI, the higher the feed efficiency. The changes in the host microbiome and metabolome contribute to the greater feed efficiency of low RFI (LRFI) animals. The aim of this study was to explore the differences in rumen microorganisms, rumen metabolites and plasma metabolites of Hu sheep with differing RFI through the microbiome and metabolome. A total of 80 Hu sheep were used. The experiment consisted of a 15-d pretrial period and a 128-d experimental period. The RFI in the experimental period was calculated for all sheep, and the sheep were screened into high RFI (HRFI, n = 8) and LRFI (n = 8) groups. The HRFI and LRFI sheep did not differ in their initial and final body weights, average daily gain and body measurements, but the dry matter intake of LRFI sheep was significantly decreased (28.4%, P < 0.001). The sheep with LRFI had higher digestibility of crude protein (P = 0.010) and ether extract (P = 0.010) compared to HRFI group. The concentrations of acetate (P = 0.036), propionate (P = 0.010), valerate (P = 0.027) and total volatile fatty acids (P = 0.048) in rumen of LRFI group were higher compared to HRFI group. The results of 16S rDNA sequencing indicated that the sheep with LRFI had higher proportions of Prevotella genus in rumen liquid (P = 0.031). The rumen metabolome and plasma metabolome results showed that the citrate cycle, pyruvate metabolism and alanine, aspartate and glutamate metabolism processes were more active for sheep in LRFI group, which provided more energy substrate such as malic acid, oxoglutaric acid and citric acid. In conclusion, sheep with LRFI can utilize feed more efficiently, and the more active energy metabolism pathway and the production of energy substances may account for the higher feed efficiency.

Effects of Centella asiatica Extracts on Rumen In Vitro Fermentation Characteristics and Digestibility.

Two in vitro experiments were conducted to evaluate the effects of Centella asiatica extract (CAE) supplementation on the rumen's in vitro fermentation characteristics. In the first experiment, CAE with five concentrations (C: 0%; T1: 3.05%; T2: 6.1%; T3: 12.2%; and T4: 24.4% CAE in diet) was supplemented in the rumen fluid and incubated for 6, 24, and 48 h to determine the optimal dosage. The total gas and methane production increased in all incubation times, and the total volatile fatty acids increased at 6 and 48 h. Ammonia nitrogen, branched chain volatile fatty acids, acetate, and butyrate were increased by CAE supplementation. T1 was chosen as the optimal dosage based on the total volatile fatty acids, branched chain volatile fatty acids, and ammonia nitrogen production. The CAE with the identified optimal dosage (T1) was incubated to identify its effect on the rumen's in vitro degradability in the second experiment. The CAE supplementation did not influence the in vitro dry matter, crude protein, or neutral detergent fiber degradability. In conclusion, CAE has no CH4 abatement or digestion promotion effects. However, CAE could be utilized as a feed additive to increase the rumen's total volatile fatty acid production without an adverse effect on the in vitro dry matter, crude protein, or neutral detergent fiber degradability.

Hematological profile, rumen fermentation, antioxidant state, and immune response of Egyptian Nubian goats fed on Astragalus membranaceus root extract supplemented ration

Background In recent years, Astragalus membranaceus extract has been widely used in animals due to their antimicrobial activities, ability to enhance immunity, and antioxidant functions. Objective We aimed to determine the antioxidant and inhibitory activities of A. membranaceus root powder (AMP) and its cytotoxicity and effects on hematological profile, rumen fermentation, antioxidant status, and immune response in Egyptian Nubian goats. Materials and methods Twenty-five goats are used in this study were received 20 g/animal/day of AMP mixed with their basic diet for 28 days. The study involved measuring the antioxidant activity of AMP using the 2-diphenyl-1-picrylhydrazyl radical scavenging assay and determining the viability and cytotoxicity percentage using the methyl-thiazolyl tetrazolium protocol. Results After 14 and 28 days of the daily feeding with 20 g of AMP, there was a significant increase in hematological profile, leukocyte count, total volatile fatty acid, and rumen ammonium concentrations with an enhancement in protozoal activity. Also, there was an increase in catalase and total antioxidant capacities along with promoting immunoglobulin (A, M, and G) contents with no significant effect on the insulin level compared with 0 days. Malondialdehyde contents decreased significantly. For all examined concentrations, A. membranaceus showed antioxidant and anti-inflammatory activities. It also showed a high cytotoxicity percentage in cancer cells. Discussion and conclusions A. membranaceus root extract supplementation significantly increases hematology parameters and rumen fermentation, and improves immune status and antioxidant activity both in-vitro and in live animals. It also exhibits potent cytotoxicity on cancer cells.

Early-life supplementation with mannan-rich fraction to regulate rumen microbiota, gut health, immunity, and growth performance in dairy goat kids

Enhancing gastrointestinal health, immunity, and digestion are key factors to support dairy goat kid performance. Several additives have been studied in relation to these actions. This study investigated the impact of mannan-rich fraction (MRF) inclusion in goat milk on the growth performance, gut health, rumen fermentation, and microbial profiles of Xinong Saanen dairy goat kids. A total of 80 kids aged 14 d and 4.72 ± 0.33 kg BW were randomly assigned into 2 groups: control and MRF (1 g/d MRF mixed into milk). Each group consisted of 40 kids with 10 kids per pen. All kids were given milk individually and fed a starter diet by pen, with the trial lasting 10 wk. Body weight and blood samples were collected on the seventh day at 2, 6, 10 and 12 wk of age, and feed intake was determined daily. From the first to seventh day at 12 wk of age, fecal samples were collected from 4 kids in each group to analyze nutrient digestibility. On the seventh day of 12 wk of age, 4 kids from each group were slaughtered for evaluation of rumen fermentation, rumen microbiota, and gut morphology. The results indicated that MRF supplementation led to greater overall BW, overall starter DMI, and overall ADG, along with a lower overall diarrhea rate. However, no difference in overall feed efficiency and apparent digestibility of nutrients was observed. Furthermore, MRF supplementation resulted in increased ileal villus height; higher RNA expression of claudin-1 and occludin in the duodenum; higher expression of ZO-1, JAM-2, and occludin in the jejunum; and higher expression of claudin-1, JAM-2, and occludin in the ileum. Additionally, the concentrations of overall IgA, overall IgM, and overall IgG were higher in the MRF group. The concentrations of ruminal acetate and total volatile fatty acid were higher with MRF supplementation (P < 0.05). Meanwhile, supplementation with MRF resulted in higher abundance of Bacteroidetes and Succinivibrio and lower abundance of Firmicutes and Succiniclasticum in the rumen. Overall, the growth performance, gut health, immunity, and ruminal microbial structure of dairy goat kids benefited from MRF supplementation.

Enhancing the nutritional quality and digestibility of citronella waste (Cymbopogon nardus) for ruminant feed through ammoniation and fermentation techniques.

Citronella grass (Cymbopogon nardus) waste, produced by distilling citronella to produce essential oil, has a high potential for use as animal feed. However, the presence of high lignin content could limit its digestibility, prompting the need for treatment to improve its quality. This study aimed to improve the nutritional value and in vitro digestibility of ammoniated and fermented citronella waste (CW). The treatments of CW included CW without treatment as a control (T0), ammoniation of CW with urea (T1), fermentation of CW with Trichoderma harzianum (T2), and a combination of ammoniation and fermentation (amofer) of CW (T3). This study employed a randomized block design with five replicates for each of the four treatments. If there was a significant effect (p < 0.05), a post hoc Duncan's multiple range test was performed to analyze the variance of the data. The process of ammoniation and fermentation led to a notable increase in crude protein (2%-6%) while decreasing crude fiber (2%-6%), neutral detergent fiber (NDF) (5%-14%), acid detergent fiber (ADF) (5%-9%), lignin (4%-9%), and cellulose (2%-10%). The treatments enhanced the digestibility of dry matter, organic matter (OM), NH3, and total volatile fatty acid by 4%-12%, 6%-19%, 0.9-10 mM, and 35-142 mM, respectively. The decrease in NDF, ADF, acid detergent lignin (ADL), and cellulose fractions was accompanied by an improvement in dry matter and OM digestibility in CW. Ammoniated-fermented (amofer) CW, followed by fermentation with T. harzianum and ammoniated urea treatment, significantly enhanced the nutritional content and in vitro digestibility. The decrease in NDF, ADF, ADL, and cellulose fractions led to an improvement in dry matter and OM digestibility in CW. The application of amofer treatment with T. harzianum maximizes CW's nutritional value and digestibility, making it the most efficient preservation method. Research is needed to explore the potential use of Aspergillus spp. and Pleurotus spp. for fermenting CW as ruminant fodder.

Impact of ginger powder (Zingiber officinale) supplementation on the performance, biochemical parameters, antioxidant status, and rumen fermentation in Ossimi rams.

Ginger (Zingiber officinale) has great potential as a growth promoter and immunostimulant in ruminant nutrition. This study assessed the impact of ginger powder supplementation on Ossimi rams' rumen fermentation, biochemical parameters, and antioxidant levels. Fifteen Ossimi rams, aged 10 ± 1.3 months and weighing 30 ± 1.5 kg. Rams were randomly divided into three experimental groups: The control group (G1) received standard feed, while ginger powder (5 g and 7 g/kg body weight [BW] for G2 and G3, respectively) mixed in water was administered to groups G2 and G3 before their standard feed. The control group recorded higher dry matter (DM) intake values (p < 0.05) than the ginger-treated groups. The ginger-treated groups showed superiority (p < 0.05) in weight gain and feed conversion compared to the control group. The digestion coefficients of DM, crude protein, and crude fiber were significantly (p < 0.05) increased by a high dose (7 g/Kg BW) of ginger supplementation, whereas organic matter, ether extract, and nitrogen-free extract digestibility remained unchanged. Compared to the control group, the rams given 5 g of ginger had significantly less (p < 0.05) total protein and globulin in their serum, but the rams given 7 g of ginger had significantly more (p < 0.05) of these proteins. In the ginger groups, these levels were significantly (p < 0.01) lower than those in the control group for serum creatinine, uric acid, urea, total lipids, triglycerides, total cholesterol, glucose, serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase. Rams given ginger had significant growth hormone, insulin-like growth factor-1, total superoxide dismutase, GSH-Px, TAC, immunoglobulin (Ig) A, and IgG enhancement (p < 0.01), and a decrease (p < 0.01) in malondialdehyde concentration compared to the control group. Significant increases in total short-chain volatile fatty acids, acetic, propionic, and isovaleric acids (p < 0.05), and significant decreases in NH3N and protozoa (p < 0.01). Ginger powder (5 g and 7 g) can improve growth, immune responses, antioxidant status, and ruminal parameters in rams. Further study is needed to evaluate the effect of ginger on different types of animals (cow, buffalo, and goat) to develop new feed additives.

Performance of dairy cows offered silages produced from grass swards harvested on either three or five occasions during the growing season

The nutritive value of grass silage can be improved by harvesting herbage at a less mature growth stage, which in practice usually involves more frequent harvests. This study examined the performance of dairy cows offered grass silages produced from perennial ryegrass (Lolium perenne) based swards harvested at 2 different frequencies during the growing season (3-harvest (3H) vs. 5-harvest (5H)). Thirty-four mid-lactation (av. 147 d in milk) dairy cows (30 multiparous, 4 primiparous) were offered either 3H or 5H silages in a continuous design (21 wk) experiment. Within each treatment cows were offered silage from each harvest (in harvest number order) for a pre-determined number of days in proportion to herbage DM yield at each harvest. Silages were offered ad libitum while a common concentrate was offered to all cows at 12.0 kg per cow/d over the first 15 wk of the study, 8.0 kg per cow/d during wk 16 -19 and 6.0 kg cow/d during wk 20 - 21. Total yield of herbage harvested over the season from within 3H and 5H were 12.6 and 11.2 t DM/ha, respectively. Across all harvests the mean ME and CP concentration of silages were 10.9 MJ/kg DM and 131 g/kg DM for 3H, and 11.5 MJ/kg DM and 152 g/kg DM for 5H. Silage DMI was greater for cows offered 5H silages compared with 3H silages (14.1 vs. 11.7 kg/d, respectively). Cows offered 5H silages had a greater daily milk yield (33.5 vs. 31.9 kg) and ECM yield (37.4 vs. 35.6 kg) compared with cows offered 3H silages. Treatment had no effect on milk fat or protein concentration. Cows offered 5H silages produced milk with greater concentrations of CLA and n-3 fatty acids. Treatment had no effect on mean BW or BCS, or on efficiency metrics such as milk yield or ECM yield per kg of DMI. Molar proportions of VFA in ruminal fluid differed between the treatments, with cows offered 3H silages having higher proportion of total butyrate (15.9 vs. 14.4% of total VFA) and lower total valerate (3.2 vs. 3.7% of total VFA) compared with those offered 5H. The acetate: propionate and acetate plus butyrate: propionate ratios were unaffected by treatment. In conclusion, increasing herbage harvesting frequency from 3 to 5 times per year improved the nutritional value of the resulting silages, and this led to higher silage DMI, milk yield and ECM yield. However, overall production efficiency (ECM/DMI) was unaffected by treatment.

Pilot-scale evaluation of cascade anaerobic digestion of mixed municipal wastewater treatment sludges.

This work assessed the performance of a pilot-scale cascade anaerobic digestion (AD) system when treating mixed municipal wastewater treatment sludges. The cascade system was compared with a conventional continuous stirred tank reactor (CSTR) digester (control) in terms of process performance, stability, and digestate quality. The results showed that the cascade system achieved higher volatile solids removal (VSR) efficiencies (28-48%) than that of the reference (25-41%) when operated at the same solids residence time (SRT) in the range of 11-15 days. When the SRT of the cascade system was reduced to 8days the VSR (32-36%) was only slightly less than that of the reference digester that was operated at a 15-day SRT (39-43%). Specific hydrolysis rates in the first stage of the cascade system were 66-152% higher than those of the reference. Additionally, the cascade system exhibited relatively stable effluent concentrations of volatile fatty acids (VFAs: 100-120 mg/l), while the corresponding concentrations in the control effluent demonstrated greater fluctuations (100-160 mg/l). The cascade system's effluent pH and VFA/alkalinity ratios were consistently maintained within the optimal range. During a dynamic test when the feed total solids concentration was doubled, total VFA concentrations (85-120 mg/l) in the cascade system were noticeably less than those (100-170 mg/l) of the control, while the pH and VFA/alkalinity levels remained in a stable range. The cascade system achieved higher total solids (TS) content in the dewatered digestate (19.4-26.8%) than the control (17.4-22.1%), and E. coli log reductions (2.0-4.1 log MPN/g TS) were considerably higher (p < 0.05) than those in the control (1.3-2.9 log MPN/g TS). Overall, operating multiple CSTRs in cascade mode at typical SRTs and mixed sludge ratios enhanced the performance, stability digesters, and digestate quality of AD. PRACTITIONER POINTS: Enhanced digestion of mixed sludge digestion with cascade system. Increased hydrolysis rates in the cascade system compared to a reference CSTR. More stable conditions for methanogen growth at both steady and dynamic states. Improved dewaterability and E. coli reduction of digestate from the cascade system.

Augmenting the Quality and Shelf Life of Ras Cheese by Adding Microencapsulated Allspice Berry Extract Nanoemulsion

AbstractThe current study was achieved to increase phenolic compounds and antioxidant content in Ras cheese by microencapsulation of the nanoemulsion of extract from the berries of allspice. The microencapsulation of the extract nanoemulsion from the berries of allspice using maltodextrin, whey protein concentrate, and guar gum was prepared by a freeze-drying process. The extract was cured, and nanoemulsion forms were prepared and evaluated for the antimicrobial effect and phenolic compound content. The morphology of microcapsules was studied by transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FT-IR) analysis. The prepared microcapsules were added to Ras cheese using ratios (1, 2, and 3% (w/w)) and then stored for 120 days for ripening and examined chemically, microbiologically, and organoleptically. The results indicated that the allspice extract in both forms has shown an inhibitory effect on all microorganisms. Moreover, the major phenol compound in allspice berry extract was gallic acid with quantities of 15,991 µg/g. Furthermore, the microcapsule efficiency was recorded at 80.97% and spherical with a diameter of 380 µm, while the nanoemulsion of extract as the core has a size of around 320 nm. The total lactic acid bacteria counts in all samples gradually declined during the ripening period. The mold and yeast count was not detected in fresh cheeses and appeared for cheese control more than in cheese with the extract. Cheese control and treatments contained lower titratable acidity, total nitrogen, soluble nitrogen, and ash ratio than the other cheese with extract treatments. The total volatile fatty acids (TVFAs) were increased through the storage period in all cheese treatments. Correspondingly, Ras cheese acceptability for sensory evaluation increased during the ripening periods in all treatments, whereas cheese supplemented with 1% microcapsules ranked the highest score for flavor and body and texture during storage gaining a high accepted point of 93.62.

Changes in the rumen development, rumen fermentation, and rumen microbiota community in weaned calves during steviol glycosides treatment.

Early weaning leads to weaning stress in calves, which hinders healthy growth and development. As an excellent sweetener applied in food, steviol glycosides (STE) has also been shown to exhibit positive biological activity in monogastric animals. Therefore, this study aimed to evaluate the impact of incorporating STE as a dietary supplement on rumen development, fermentation, and microbiota of rumen in weaned calves. This study selected 24 healthy Holstein bull calves and randomly allocated them into two groups (CON and STE). The results indicated that supplementation STE group improved rumen development in weaned calves, as demonstrated by a marked increase in the weight of the rumen, as well as the length and surface area of the rumen papilla. Compared with the CON group, the concentrations of total volatile fatty acids (TVFA), propionate, butyrate, and valerate were higher in the STE group. Moreover, STE treatment increased the relative abundance of Firmicutes and Actinobacteria at the phylum level. At the genus level, the STE group showed a significantly increased relative abundance of Succiniclasticum, Lachnospiraceae_NK3A20_group, and Olsenella, and a decreased relative abundance of Acinetobacter compared to the CON group. Pusillimonas, Lachnospiraceae_NK3A20_group, Olsenella, and Succiniclasticum were significantly enriched in rumen chyme after supplementation with STE, as demonstrated by LEfSe analysis. Overall, our findings revealed that rumen bacterial communities altered in response to the dietary supplementation with STE, and some bacterial taxa in these communities may have positive effects on rumen development during this period.

In vitro fermentation end-products and rumen microbiome as influenced by microencapsulated phytonutrient pellets (LEDRAGON) supplementation

The objective of this study was to investigate the effect of microencapsulated bioactive compounds from lemongrass mixed dragon fruit peel pellet (MiEn-LEDRAGON) supplementation on fermentation characteristics, nutrient degradability, methane production, and the microbial diversity using in vitro gas production technique. The study was carried out using a completely randomized design (CRD) with five levels of MiEn-LEDRAGON supplementation at 0, 1, 2, 3, and 4% of the total dry matter (DM) substrate. Supplementation of MiEn-LEDRAGON in the diet at levels of 3 or 4% DM resulted in increased (p < 0.05) cumulative gas production at 96 hours (h) of incubation time, reaching up to 84.842 ml/ 0.5 g DM. Furthermore, supplementation with 3% MiEn-LEDRAGON resulted in higher in vitro nutrient degradability and ammonia–nitrogen concentration at 24 h of the incubation time when compared to the control group (without supplementation) by 5.401% and 11.268%, respectively (p < 0.05). Additionally, supplementation with MiEn-LEDRAGON in the diet led to an increase in the population of Fibrobacter succinogenes at 24 h and Butyrivibrio fibrisolvens at 12 h, while decreasing the population of Ruminococcus albus, Ruminococcus flavefaciens, and Methanobacteriales (p < 0.05). Moreover, supplementation of MiEn-LEDRAGON in the diet at levels of 2 to 4% DM resulted in a higher total volatile fatty acids (VFA) at 24 h, reaching up to 73.021 mmol/L (p < 0.05). Additionally, there was an increased proportion of propionic acid (C3) and butyric acid (C4) at 12 h (p < 0.05). Simultaneously, there was a decrease in the proportion of acetic acid (C2) and the ratio of acetic acid to propionic acid (C2:C3), along with a reduction of methane (CH4) production by 11.694% when comparing to the 0% and 3% MiEn-LEDRAGON supplementation (p < 0.05). In conclusion, this study suggests that supplementing MiEn-LEDRAGON at 3% of total DM substrate could be used as a feed additive rich in phytonutrients for ruminants.

Impact of aging of primary and secondary polystyrene nanoplastics on the transmission of antibiotic resistance genes in anaerobic digestion

Sewage sludge is a significant reservoir of nano/microplastics (NPs/MPs) and antibiotic resistance genes (ARGs). Research has revealed that NPs/MPs may exert an inhibitory effect on anaerobic digestion (AD) of sludge. Moreover, NPs/MPs can influence microbial community diversity and composition, potentially increasing ARGs dissemination. The morphological changes to NPs/MPs surface due to aging contribute to modifying hydrophobic properties. To date, there is limited comprehension regarding how various surface properties of NPs influence ARGs dissemination during AD. This study investigated the impact of primary aged/non-aged and secondary aged/non-aged polystyrene nanoplastics (PSNPs) on ARGs and mobile genetic elements (MGEs) propagation during AD. The findings indicated that the UV-aging process resulted in surface oxidation and distinct morphological characteristics in both primary and secondary PSNPs, while the surface oxidation effect was more pronounced in the secondary aged PSNPs. High concentrations (150 μg/L) of primary and secondary PSNPs inhibited methane production, with secondary PSNPs causing greater inhibition by 16 to 20 % compared to control. In contrast, low concentration (25 μg/L) had negligible or slightly positive effects on methane production. PSNPs at 150 μg/L reduced total VFA concentration, indicating an inhibitory effect on the fermentation step in the AD process. Primary and secondary PSNPs exhibited changes in EPS characteristics. ARGs abundance was enriched in reactors amended with PSNPs, with the highest abundance of 8.54 × 105 copies/g sludge observed in the secondary aged PSNPs (150 μg/L) reactor. Reactors exposed to aged PSNPs exhibited a relatively higher abundance of ARGs compared to reactors exposed to non-aged PSNPs. Exposure to PSNPs increased the microbial community diversity within the digesters and triggered the enrichment of Comamonadaceae and Syntrophaceae, belonging to Proteobacteria phylum. On the other hand, archaeal communities tended to shift towards hydrogenotrophic methanogens in PSNPs reactors. The correlation analysis showed that Comamonadaceae were positively correlated with the majority of ARGs and intl1. A positive correlation was observed between MGEs and most ARGs, suggesting that the increased proliferation of ARGs under PSNPs exposure may be linked to the abundance of MGEs, which in turn promotes the growth of hosts carrying ARGs. These findings suggest that aged and non-aged NPs could substantially impact the spread of ARGs and MGEs, which also led to notable alterations in the composition of the microbial community. Overall, this study provides valuable insights into the multifaceted impacts of PSNPs with various characteristics on AD processes, microbial communities, and ARGs proliferation, highlighting the urgent need for comprehensive assessments of NPs pollutants in the environment.

Effects of sodium chloride intake on urea-N recycling and renal urea-N kinetics in lactating Holstein cows

The effects of high (2.5% of DM) versus normal dietary sodium chloride (NaCl) intake on renal urea-N kinetics and urea-N metabolism were investigated in 9 rumen-cannulated and multi-catheterized lactating dairy cows in a crossover design with 21-d periods. It was hypothesized that urinary urea-N excretion would be greater, and blood urea-N concentration lower in response to greater diuresis induced by high NaCl intake. Also, urea-N transport across ruminal and portal drained viscera (PDV) tissues was hypothesized to be affected by dietary sodium intake. A second experiment was conducted using 8 lactating cows in a crossover design with 14-d periods to test high NaCl (2.5% of DM) versus high KCl (3.2% of DM) intake on milk yield and milk urea-N concentrations. Experiment 1 showed that despite greater diuresis there was no effect of high NaCl intake on urinary urea-N excretion or blood urea-N concentration. The high NaCl intake did not affect rumen ammonia concentrations, total rumen VFA concentrations, ruminal venous - arterial concentration differences for ammonia, or ammonia absorption indicating that high NaCl did not adversely affect ruminal fermentation and microbial protein synthesis. High NaCl intake did not affect the total amount of urea-N transport from blood to gut, but ruminal venous - arterial concentration differences for urea-N were lower with high NaCl and ruminal extraction of arterial urea-N was numerically smaller, indicating that the ruminal epithelial urea-N transport was lower with high NaCl. Energy corrected milk yield was greater with high NaCl (3.2 ± 1.5 kg/d); however, milk urea-N concentrations were not affected by treatment. In experiment 2, ECM was greater with NaCl (1.4 ± 0.31 kg/d) compared with KCl (30.2 and 28.8 ± 0.91 kg ECM / d, respectively). Milk urea-N concentration was lower with KCl, suggesting a urea-N lowering effect in milk not evident with high NaCl intake. In conclusion, the present data show that dietary Na intake of 12-13 g/kg DM was followed by greater diuresis but did not impact urea-N excretion or blood urea-N concentration. High NaCl intake did not affect the total amount of urea-N transfer across PDV tissues. Energy corrected milk yield was greater with high NaCl compared with both control and feeding KCl, however, with KCl milk urea-N decreased.