Concentrations Of Isobutyrate Research Articles

Use of different carbohydrate sources associated with urea and implications for in vitro fermentation and rumen microbial populations

Context Alternative feed sources have been investigated as replacements for green forages and cereal grains traditionally used in ruminant feed. We hypothesised that, when replacing sources of true protein with non-protein nitrogen (NPN) in the ruminant diet, the efficiency of utilisation of the NPN may be affected by the source of energy and that different energy resources used as alternatives to maize may improve efficiency and maximise ruminal fermentation characteristics. Aims The objective of this study was to evaluate the effects of diets containing different carbohydrate sources associated with urea on in vitro ruminal fermentation and rumen microbial profile. Methods Four diets based on Tifton 85 Bermuda grass hay (584 g/kg dry matter) were tested as substrates: cornmeal + soybean meal (C + SM, typical diet), cornmeal + urea (C + U), cassava scraping + urea (CS + U), and spineless cactus + urea (SC + U). The experimental design consisted of randomised blocks with four treatments and five blocks. Five adult Nellore cattle with permanent fistula in the rumen were used as inoculum donors. The semi-automatic in vitro gas production technique was used in two experiments. Quantitative real-time PCR was used to monitor the changes in the rumen microbial community. Key results The diets containing C + U and CS + U decreased (P < 0.05) concentrations of isobutyrate, isovalerate, and valerate after 24 h of incubation, and all diets containing urea decreased (P < 0.05) concentrations of isobutyrate, isovalerate and valerate after 96 h and increased (P < 0.05) acetate:propionate ratio. After 96 h of incubation, the diets containing CS + U and SC + U resulted in a lower (P < 0.05) population of Ruminococcus flavefaciens than the C + U diet, and a lower (P < 0.05) population of Streptococcus bovis than the C + SM diet. Conclusions From our results, a diet containing cassava scraping produces more methane per unit of degraded organic matter, which reduces fermentation efficiency. Diets that contain corn with either soybean meal or urea result in greater degradability with lower gas production rates than diets that contain either cassava scrapings or spineless cactus with urea. Diets containing urea as a total substitution for soybean meal alter the production of short-chain fatty acids and reduce the populations of S. bovis and R. flavefaciens. Implications Use of urea to replace soybean meal in the ruminant diet alters ruminal fermentation and rumen microbial population.

Dietary supplementation of a fiber-prebiotic and saccharin-eugenol blend in extruded diets fed to dogs.

Prebiotics and dietary fibers are nondigestible ingredients that may confer benefits to the host by selectively stimulating beneficial intestinal bacteria and microbial-derived metabolites that support gut and host health. This experiment evaluated the effects of a blend of prebiotics and dietary fibers on apparent total tract digestibility (ATTD) and fecal metabolites related to gastrointestinal health in adult dogs. Four diets containing either 5% cellulose (control; CT), 5% dietary fiber and prebiotic blend (FP), 0.02% saccharin and eugenol (SE), or 5% fiber blend plus 0.02% saccharin and eugenol (FSE) were formulated to meet or exceed the AAFCO (2017) nutritional requirements for adult dogs. Eight adult female beagles (mean age 4.2 ± 1.1 yr; mean BW = 10.8 ± 1.4 kg; mean BCS = 5.8 ± 0.6) were randomly assigned to 1 of the 4 dietary treatments using a replicated 4 × 4 Latin square design. Each experimental period consisted of 14 d (10 d of diet adaptation and 4 d of total and fresh fecal and total urine collection). All animals remained healthy throughout the study, with serum metabolites being within reference ranges for adult dogs. All diets were well accepted by the dogs, resulting in similar (P > 0.05) daily food intakes among treatments. Likewise, fecal output and scores did not differ (P > 0.05) among dietary treatments, with the latter being within the ideal range (2.5–2.9) in a 5-point scale. All diets were highly digestible and had similar (P > 0.05) ATTD of dry matter (81.6%–84.4%), organic matter (86.4%–87.3%), and crude protein (86.6%–87.3%). However, total dietary fiber (TDF) digestibility was greater for dogs fed the FSE diet (P < 0.05) in contrast with dogs fed the CT and SE diets, whereas dogs fed FP diets had intermediate TDF digestibility, but not different from all other treatments. Fecal acetate and propionate concentrations were greater (P < 0.05) for dogs fed FP and FSE diets. Fecal concentrations of isobutyrate and isovalerate were greater for dogs fed CT (P < 0.05) compared with dogs fed the other three treatments. No shifts in fecal microbial richness and diversity were observed among dietary treatments. Overall, the data suggest that dietary supplementation of fiber and prebiotic blend was well tolerated by dogs, did not cause detrimental effects on fecal quality or nutrient digestibility, and resulted in beneficial shifts in fecal metabolites that may support gut health.

Effect of dietary corn gluten inclusion on rumen fermentation, microbiota and methane emissions in goats

The study was to evaluate replacing corn meal (CM) by corn gluten (CG) on intake, digestibility, ruminal fermentation, CH4 emissions and microbial abundance in goats. The experiment was performed using randomized block design with 2 dietary treatments (CM and CG with 400 g/kg DM each). Replacing CM with CG increased NDF and CP intake and decreased starch intake. Goats fed CG diet had lower ruminal dissolved hydrogen (dH2) (-43%, P = 0.009) and dissolved methane (dCH4) (-30%, P = 0.001) concentrations than those fed with CM diet. An interaction between treatment and time (P = 0.03) was observed for dH2S with an increase (P < 0.001) in dH2S concentration (CG versus CM, +63%, P < 0.001) happened at 2.5 h after morning feeding. Goats fed with CG diet had lower (P = 0.004) butyrate molar percentage, and greater (P < 0.01) ammonia concentration and molar percentage of valerate and isobutyrate than those fed with the CM diet. Goats fed with CG diet decreased (P = 0.01) CH4 emission expressed as g/d and g/kg DMI. Goats fed with CG diet decreased 16S rRNA gene copies of R. amylophilus (P = 0.003), and increased 18S rRNA gene copies of fungi (P = 0.05) and 16S rRNA gene copies of F. succinogenes (P = 0.03). In summary, replacing CM with CG decreases starch and increases fiber intake, and growth of fibrolytic fungi and F. succinogenes, and inhibits growth of R. amylophilus. An increase in sulfur content after replacing CM with CG provides additional H2 sink, which causes an increase in ruminal dH2S and reduction in CH4 emissions. Corn gluten could be an alternative feed to decrease the enteric CH4 emission in ruminant production.

Short communication: Comparison of pH, volatile fatty acids, and ammonia in preweaning and postweaning ruminal fluid samples obtained via rumenocentesis and stomach tube from dairy calves

This research was undertaken with an aim to compare the pH, volatile fatty acid (VFA) profile, and ammonia concentration of ruminal fluid samples from pre- and postweaning dairy calves that were obtained through rumenocentesis (RC) and an oral stomach tube (ST) as well as to monitor the health-related complications of sampling techniques. During the first 84 days of life, 40 Polish Holstein–Friesian calves were grouped by dam parity (equal numbers of calves born to primiparous and multiparous cows) and assigned randomly to two treatment diets: concentrate, which comprised starter feed without oat hay (C; n = 20), and concentrate with forage, which comprised starter feed with 10% oat hay (CF; n = 20). The higher value of ruminal fluid pH was noted in the ST compared to the RC method. The average difference in pH between methods was 0.33 in the whole experimental period, and that difference was not affected by the treatment diet. We noted higher concentrations of ruminal ammonia; total VFAs; and molar concentrations of acetate, propionate, n-butyrate, isobutyrate, n-valerate, and isovalerate for the RC, compared with the ST method. Minor complications were recorded after ruminal fluid sampling via RC in three 8-week-old calves. Differences in ruminal fluid pH and fermentation parameters suggested that a comparison of rumen parameters sampled with different methods might be unreliable and should be avoided. Moreover, given its minimal impact on animal health, RC can be recommended for ruminal fluid sampling from dairy calves.

Effects of dietary supplementation of inulin on rumen fermentation and bacterial microbiota, inflammatory response and growth performance in finishing beef steers fed high or low-concentrate diet

The objective of this study was to evaluate the effects of dietary inulin supplementation on rumen fermentation and bacterial microbiota, inflammatory response, and growth performance in finishing beef steers fed high or low-concentrate diet. Twenty-four Simmental × Luxi crossbred steers were used under a 2 × 2 treatment with 2 diet types and 2 inulin levels. The 2 diet types consisted of a low-concentrate diet (LCD; concentrate:roughage = 40:60) and a high-concentrate diet (HCD; concentrate:roughage = 60:40) and inulin was supplemented into the diets at 0 or 2% (wt/wt). The trial lasted for 42 days. Rumen fluid and plasma samples were collected at the end of the animal trial. Rumen fluid samples were analyzed for pH, short-chain fatty acids, endotoxin (lipopolysaccharide, LPS), and bacterial microbiota. Illumina Miseq sequencing of the 16S rRNA gene was applied to investigate ruminal bacterial microbiota. Plasma samples were analyzed for concentrations of pro-inflammatory cytokines including interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor alpha as well as acute phase proteins including LPS-binding protein, haptoglobin, serum amyloid A, and C-reactive protein. Results showed that the high dietary concentrate level shifted the ruminal fermentation pattern from acetate towards propionate, butyrate and valerate, and improved growth performance. However, the high dietary concentrate level promoted ruminal pH reduction and LPS release, decreased bacterial diversity and richness, modified bacterial composition, and increased systemic inflammatory response. Inulin supplementation into the LCD increased ruminal concentrations of propionate, butyrate and iso-butyrate, and improved growth performance. Inulin supplementation into the HCD increased bacterial alpha indices (1628 vs. 1364, 1574 vs. 1329, and 0.985 vs. 0.975 for ACE, Chao1, and Simpson indices, respectively) and operational taxonomic units (1243 vs. 1080), increased Bacteroidetes to Firmicutes ratio (0.84 vs. 0.59), and enhanced final body weight and feed utilization. In conclusion, dietary supplementation with inulin, regardless of the dietary concentrate levels, improved growth performance of finishing beef steers probably through either altering the fermentation pattern or improving ruminal bacterial microbiota, depending on the diet type. Nonetheless, inulin supplementation did not suppress inflammatory response resulting from feeding high-concentrate diet in beef steers.

Dietary Supplementation With Leucine or in Combination With Arginine Decreases Body Fat Weight and Alters Gut Microbiota Composition in Finishing Pigs.

Obesity was associated with change in gut microbiota composition and their metabolites. We investigated the effects of dietary supplementation with leucine (Leu) in combination with arginine (Arg) or glutamic acid (Glu) on body fat weight, composition of gut microbiota, and short-chain fatty acids (SCFAs) concentration in the colon. Forty-eight Duroc × Large White × Landrace pigs with an initial body weight of 77.08 ± 1.29 kg were randomly assigned to one of the four groups (12 pigs per group). The pigs in the control group were fed a basal diet supplemented with 2.05% alanine (isonitrogenous control, BD group), and those in the three experimental groups were fed a basal diet supplemented with 1.00% Leu + 1.37% alanine (Leu group), 1.00% Leu + 1.00% Arg (Leu_Arg group), or 1.00% Leu + 1.00% Glu (Leu_Glu group). We found that dietary supplementation with Leu alone or in combination with Arg decreased (p < 0.05) body fat weight, and increased (p < 0.05) colonic propionate and butyrate concentrations compared to the BD group. The mRNA expression levels of genes related to lipolysis increased (p < 0.05) in the Leu or Leu_Arg group compared to the BD group. Negative relationships (p < 0.05) were observed between body fat weight, colonic propionate, and butyrate concentrations. Compared to the BD group, the abundance of Actinobacteria was higher (p < 0.05) in the Leu group, and that of Clostridium_sensu_stricto_1, Terrisporobacter, and Escherichia-Shigella were higher in the Leu_Arg group. The abundance of Deinococcus-Thermus was negatively correlated (p < 0.05) with body fat weight, and was positively correlated (p < 0.05) with butyrate, isovalerate, propionate, and isobutyrate concentrations, and that of Cyanobacteria was positively correlated (p < 0.05) with butyrate, propionate, and isobutyrate concentrations. In conclusion, these findings suggest that decreased body fat weight in pigs can be induced by Leu supplementation alone or in combination with Arg and is associated with increased colonic butyrate and propionate concentrations. This provides new insights for potential therapy for obesity.

PSI-2 Impact of an extended-release dewormer on rumen VFAs and blood metabolites

Abstract The ratio of glucogenic to lipogenic acids in ruminal VFAs can have a direct impact on nutrient utilization. The objective of this study was to compare the effects of an extended-release injectable dewormer [LongRange® (eprinomectin)] to a traditional shorter-acting injectable dewormer [Ivomec® (doramectin)] on rumen VFA profiles and blood metabolites. Ruminally cannulated lactating cows (2yr of age) were randomly allotted to one of the two dewormers (n = 5/treatment) at the time of being moved to spring grazing (day of AI). Blood samples, rumen pH, and rumen fluid were collected prior to treatment on d 0, d 15, and approximately every 30d thereafter until d 137 and analyzed by analysis of repeated measures. Fecal samples were collected at the start, middle, and end of the study to determine parasite fecal egg count. At the initiation of the study only 3 animals had any detectable parasites by fecal egg count and at the middle of the study all animals treated with the traditional dewormer had detectable parasites. Animals treated with the extended-release dewormer had no detectable parasite load throughout the study. There was no effect of treatment or treatment by time on rumen pH (P = 0.64, 0.55) or circulating NEFA concentrations (P = 0.60, 0.65) but both changed over time (P ≤ 0.01). Circulating glucose concentrations were not affected by treatment (P = 0.71) or time (P = 0.15), but there was a treatment by time interaction (P = 0.03) with glucose concentrations increased on day 32 in the extended-release dewormer. Concentrations of rumen ammonia, total VFAs, acetate, propionate, isobutyrate, butyrate, isovalerate, and valerate were not impacted by treatment (P &gt; 0.20), but there was an effect of time (P = 0.10). In summary, controlling parasite load during a 5mo grazing season can improve nutrient utilization in cattle.

146 Effects of feeding soluble fiber (dextrin) to pigs pre- and post-weaning on growth performance and volatile fatty acid (VFA) production

Abstract Thirty-two barrows were used in a 35-d experiment with the objective of evaluating effects of supplemental soluble fiber (dextrin) pre- and post-weaning on growth performance and VFA production. Pigs were blocked by genetics and BW, and randomly allotted to treatments in a 2x2 factorial design with or without fiber pre-weaning and with or without fiber post-weaning. Fiber was suspended in chocolate milk and administered orally through a syringe from 14 d prior to weaning until 4 d post-weaning, after which it was included in the diet at 1%. At weaning, pigs were group housed by treatment and allowed ad libitum access to a common starter diet. On d 4 post-weaning, pigs were moved to individual pens and fed diets with or without 1% fiber. Weights and feed intake were recorded 14 and 3 d prior to weaning and on d 0, 4, 11, and 21 post-weaning. On d 21 post-weaning, pigs were euthanized, and large intestine contents were collected for VFA analysis. Data were analyzed using the GLM procedure of SAS with pig as the experimental unit. Growth performance was not affected (P &gt; 0.10) by treatment. A trend for an interaction of pre- and post-weaning fiber supplementation was observed for acetate (P = 0.052) and butyrate (P = 0.087) concentrations in large intestine contents. Pigs fed fiber only in the nursery had the highest acetate concentration, while pigs never receiving fiber had the lowest concentration. Pre-weaning fiber supplementation followed by no fiber in the nursery resulted in the highest butyrate concentrations with all other treatments being similar. Fiber supplementation pre-weaning tended (P = 0.053) to reduce isobutyrate concentrations. Pigs not receiving fiber post-weaning had increased valerate concentrations (P = 0.0245). There were no changes observed in propionate or isovalerate concentrations (P &gt; 0.10). Fiber supplementation caused alterations in VFA concentrations when fed during pre- and post-weaning, indicating possible shifts in the microbiome, immune status and barrier function of the intestinal tract.

The production of short chain fatty acid and colonic development in weaning piglets.

Weaning process widely affects the small intestinal structure and function in piglets, while the responses of large intestine to weaning stress are still obscure. The purpose of this study was to determine the developmental changes (i.e., short chain fatty acids (SCFAs) concentrations, growth parameters, crypt-related indices and antioxidant capacity) in colon of piglet during weaning. Forty piglets were weaned at day 21 and euthanized to collect colonic tissues and digesta samples on day 0, 1, 3, 7 and 14 post-weaning (n=8). Piglet growth performance was improved (p<.001) on day 7 and 14 post-weaning. The concentrations of acetate, propionate, butyrate, valerate, isobutyrate, isovalerate and total SCFAs were higher (p<.001) during the late post-weaning period. The mRNA abundances of SCFAs transporters were greater (p<.001) on day 7 and 14. The absolute and relative weights, absolute length and perimeter of colon were greater (p<.001) on day 7 and 14. Similarly, post-weaning increases (p<.001) in colonic crypt depth and Ki67 positive cells numbers per crypt were observed during the same period. Colonic crypt fission indices decreased (p<.01), while total crypt numbers increased (p<.001) on day 14 after weaning. Moreover, total SCFAs concentration was significantly associated with colonic growth parameters and Ki67 cells/crypt (p<.001). In addition, catalase content was decreased on day 3, 7, and 14, whereas, the concentrations of total superoxide dismutase (T-SOD) and manganese-containing superoxide dismutase (MnSOD) were higher (p<.05) on day 1 and 3 post-weaning. These results showed that weaning process has a significant effect on colonic growth and development, which might be associated with the change of SCFAs concentrations in colon.

Evaluation of a single-flow continuous culture fermenter system for determination of ruminal fermentation and enteric methane production.

A 4-unit, single-flow continuous culture fermenter system was developed to assess in vitro nutrient digestibility, volatile fatty acid (VFA) concentration and daily enteric methane (CH4 ) production of ruminant diets. The objective was to develop a closed-vessel system that maintained protozoal populations and provided accurate predictions of total CH4 production. A diet of 50% orchardgrass (Dactylis glomerata L.) and 50% alfalfa (Medicago sativa L.) was fed during 4, 10-day periods (7-day adaptation and 3-day collection). Fermenters were fed 82g of dry matter (DM)/day in four equal feedings. pH and temperature were taken every 2min, and CH4 concentration was measured every 10min. Samples for DM and protozoal counts were taken daily, and daily effluent samples were collected for determination of DM, VFA and NH3 -N concentrations. There was no effect (p>0.17) of adaptation versus collection days on vessel and effluent DM, temperature or pH. Initial protozoal counts decreased (p<0.01), but recovered to initial counts by the collection period. Total VFA, acetate, propionate and isobutyrate concentrations did not differ (p≥0.13) among periods or days of the collection period. There was no difference (p≥0.37) among days or periods in total daily CH4 production and CH4 production per g of OM, NDF, digestible OM or digestible NDF fed. Data collected throughout 4 experimental periods demonstrated that the system was able to reach a steady state in fermentation well within the 7-day adaptation period and even typically variable data (i.e., CH4 production) were stable within and across periods. While further research is needed to determine the relationship between this system and in vivo data, this continuous culture fermenter system provides a valid comparison of in vitro ruminal fermentation and enteric CH4 production of ruminant diets that can then be further validated with in vivo studies.

Hermetia illucens larvae as a potential dietary protein source altered the microbiota and modulated mucosal immune status in the colon of finishing pigs

BackgroundInsects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred (Duroc × Landrace × Large White) female pigs (initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet (Control group) and two diets corresponding to 4% (H1 group) and 8% (H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens (replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment (n = 8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.ResultsThe results showed that the H1 diet significantly increased the abundance of Lactobacillus, Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group (P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group (P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group (P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group (P < 0.05); the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower (P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group (P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole (P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines (IFN-γ) compared with pigs in the control group (P < 0.05), and up-regulated anti-inflammatory cytokine (IL-10) and intestinal barrier genes (ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group (P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.ConclusionsCollectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.

Rumen parameters of yaks (Bos grunniens) and indigenous cattle (Bos taurus) grazing on the Qinghai-Tibetan Plateau.

Yaks and indigenous Qaidam cattle and cattle-yak crosses (C×Y) graze on the Qinghai-Tibetan Plateau (QTP) throughout the year, but yaks are raised at higher elevations than cattle. Yaks do not receive supplementary feed whereas cattle require supplementary feed during harsh winter. We hypothesized that yaks would cope with the severe conditions of the QTP better than cattle and utilize the pasture more efficiently. We also hypothesized that differences between species would be pronounced in winter, when conditions are particularly harsh. To test these hypotheses, seasonal rumen fluid parameters of yaks, C×Y and cattle (n=3 for each) were examined. Rumen fluid was collected in summer and winter from each genotype 2, 5 and 12hr after a day of grazing. Concentrations of total volatile fatty acid (VFA), acetate, propionate, isobutyrate and isovalerate were greater in yaks than in cattle in summer (p<0.05), while propionate concentration was lower in yaks than in cattle in winter (p<0.05). Concentrations of ammonia and urea were greater (p<0.001) in yaks than in cattle (p<0.001) in summer, whereas, concentrations of free amino acids (AA) were greater in cattle than in yaks in summer and winter (p<0.001). Concentrations of total VFA, acetate, propionate and butyrate decreased linearly (p<0.05), whereas concentrations of isobutyrate and isovalerate increased linearly for yak and C×Y with sampling time (p<0.05) in summer. In summer, concentrations of isobutyrate and isovalerate were greater in yaks than in cattle (p<0.05). In conclusion, rumen fermentation characteristics of yaks showed that they coped better than cattle or C×Y in the harsh climate as we hypothesized. However, in contrast to our hypothesis, this emerged only in summer, when pasture was plentiful and not in winter, when pasture was scarce.

Lactation performance and rumen fermentation in dairy cows fed a diet with alfalfa hay replaced by corn stover and supplemented with molasses.

ObjectiveThe objective of current study was to investigate the lactation performance and rumen fermentation characteristics of dairy cows fed a diet with alfalfa hay replaced by corn stover but supplemented with molasses.MethodsSixteen Holstein cows in mid-lactation were randomly assigned to 1 of 2 dietary treatments: i) alfalfa based diet (AH), and ii) corn stover based diet supplemented with molasses (CSM). The experiment was conducted according to a 2×2 crossover design with 22-d each period, consisting of 17 d for adaptation and 5 d for data and samples collection.ResultsDry matter intake and milk yield were higher for cows fed AH than CSM (p<0.01). Milk protein content and nitrogen conversion were higher (p<0.05), while milk urea nitrogen was lower (p<0.01) for cows fed AH than CSM-fed cows. Contents of milk total solids, fat and lactose were not different between two groups (p>0.10). Total rumen volatile fatty acid concentration tended to be higher (p = 0.06) for cows fed AH than CSM-fed cows. Molar proportion of acetate was lower (p = 0.04), but valerate was higher (p = 0.02) in cows fed AH than CSM-fed cows. Rumen concentration of propionate, and isobutyrate, and ratio of acetate to propionate tended to be different (p<0.10) between two groups. The feed cost per kilogram of milk was lower in CSM than AH (p<0.01). No differences were found in feed efficiency and most plasma parameters tested (p>0.10).ConclusionIn comparison with AH diet, CSM diet could be fed to dairy cows without negative effect on feed efficiency, ruminal fermentation, but economically beneficial, indicating that CSM could be an alternative choice for dairy farms instead of AH to feed mid-lactation dairy cows.

Lentinan modulates intestinal microbiota and enhances barrier integrity in a piglet model challenged with lipopolysaccharide.

The intestinal microbiota plays a vital role in metabolism, pathogen resistance, and immune development in host cells, and is modifiable by dietary change. Lentinan (LNT), a type of mushroom polysaccharide, is known to ameliorate intestinal inflammation with the potential of therapeutic effect on digestive diseases. We hypothesized that LNT could alleviate Escherichia coli lipopolysaccharide (LPS)-induced intestinal injury via regulating the composition and metabolites of intestinal microbiota in a piglet model. Twenty-four weaned piglets were used in a 2 × 2 factorial design, and the main factors included a dietary treatment (basal or LNT diet) and immunological challenge (LPS or saline). After feeding basal or LNT diet for 21 days, pigs were injected with LPS or saline. At 4 h post-injection, pigs were killed and jejunum, ileum and cecal digesta were collected. LNT improved intestinal morphology and barrier function. LNT also inhibited inflammatory signaling pathways (toll-like receptor 4 and nucleotide binding oligomerization domain protein) and pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β and interleukin-6) expression, as well as up-regulated the heat shock protein 70 expression in small intestine. In addition, LNT enhanced the concentrations of propionate, butyrate, isobutyrate and isovalerate in cecal digesta, resulting in a significant increase in histone acetylation without affecting the protein level of G protein-coupled receptor 41 (GPR41), a short chain fatty acid receptor. Bacterial 16S rRNA gene pyrosequencing showed that LNT had a great impact on gut microbiota composition at different taxonomic levels. Moreover, the correlation analysis revealed some potential relationships between cecal metabolites and certain intestinal microbiota. These results indicate that LNT promotes intestinal health, in part, through altering intestinal microbiota composition and increasing the short chain fatty acid synthesis, which subsequently lead to a reduction in inflammation and hyper-acetylation of histones.

Crushed crambe from biodiesel production as replacement for soybean meal in the supplement of steers grazing

To evaluate the substitution of soybean meal by crushed crambe as a source of protein, five crossbred steers rumen cannulated weighting 426 ± 25 kg BW were distributed in a 5 × 5 Latin square design. The steers were allocated in different levels of crushed crambe groups (0, 25, 50, 100 and 150 g/kg in concentrate supplement). Dry matter intake (DMI), rumen fluid pH, nitrogen (N) urinary excretion, propionate and isovalerate ruminal concentrations increased linearly (p < .05) with the replacement of soybean meal by crushed crambe. Crude protein (CP) intake, butyrate and valerate concentrations, and N retention and balance (g/d) showed linear decreases by the inclusion of crushed crambe. There was a quadratic decrease (p < .05) for neutral detergent fibre (NDF) intake and valerate concentration. Total short-chain fatty acids (SCFAs) increased quadratically (p < .05) with the inclusion of crushed crambe. The supplement and total DMI, digestibility of DM, CP and NDF, N–NH3, acetate, isobutyrate concentrations and intake, excretion faecal and total of N, microbial protein synthesis, urinary excretion and blood concentration of urea and creatinine were not affected (p > .05) by the crushed crambe inclusion in the diet. It is recommended that 100 g/kg of the crushed crambe inclusion replacing soybean meal supplements to grazing steers because improved supplement DMI and total SCFAs, reducing ruminal fermentation and nitrogen excretion, without affecting digestibility and microbial protein synthesis.HighlightsDM intake and digestibility were not affected in steers fed crushed crambe.Urinary N excretion increased with crushed crambe replacing soybean meal.

Treatment of corn with lactic acid or hydrochloric acid modulates the rumen and plasma metabolic profiles as well as inflammatory responses in beef steers

BackgroundHigh-grain diets that meet the energy requirements of high-producing ruminants are associated with a high risk of rumen disorders. Mild acid treatment with lactic acid (LA) has been used to modify the degradable characteristics of grains to improve the negative effects of high-grain diets. However, the related studies mainly focused on dairy cows and explored the effects on rumen fermentation, production performance, ruminal pH and so forth. And up to date, no studies have reported the hydrochloric acid (HA) treatment of grains for ruminant animals. Therefore, based on metabolomics analysis, the aim of this study was to evaluate the effects of treatment of corn by steeping in 1% LA or 1% HA for 48 h on the rumen and plasma metabolic profiles in beef steers fed a high corn (48.76%) diet with a 60:40 ratio of concentrate to roughage. The inflammatory responses of beef cattle fed LA- and HA-treated corn were also investigated.ResultsBased on ultra-high-performance liquid tandem chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS) metabolomics and multivariate analyses, this study showed that steeping corn in 1% LA or 1% HA modulated the metabolic profiles of the rumen. Feeding beef steers corn steeped in 1% LA or 1% HA was associated with lower relative abundance of carbohydrate metabolites, amino acid metabolites, xanthine, uracil and DL-lactate in the rumen; with higher ruminal pH; with lower concentrations of acetate, iso-butyrate and iso-valerate; and with a tendency for lower ruminal lipopolysaccharide (LPS) concentrations. Moreover, the data showed lower concentrations of plasma C-reactive protein, serum amyloid A, haptoglobin, interleukin (IL)-1β and IL-8 in beef steers fed 1% LA- or HA-treated corn. The 1% LA treatment decreased the concentrations of plasma LPS, LPS-binding protein and tumour necrosis factor-alpha and the relative abundance of L-phenylalanine, DL-3-phenyllactic acid and tyramine in plasma. The 1% HA treatment decreased the relative abundance of urea in plasma and increased the relative abundance of all amino acids in the plasma.ConclusionsThese findings indicated that LA or HA treatment of corn modulated the degradation characteristics of starch, which contributed to improving the rumen and plasma metabolic profiles and to decreasing inflammatory responses in beef steers fed a high-concentrate diet.

Effects of inulin supplementation to piglets in the suckling period on growth performance, postileal microbial and immunological traits in the suckling period and three weeks after weaning

ABSTRACTThe aim of this study was to investigate the effect of inulin (IN) supplementation to suckling piglets at and 3 weeks post-weaning. A total of 72 newborn piglets were used. Twenty-four piglets per group received different amounts of IN during the suckling period: (a) CON: no IN; (b) IN-0.5: 0.5 g IN/d on the 1st week, 1 g IN/d on the 2nd week, 1.5 g IN/d on the 3rd week and 2 g IN/d on the 4th week, or (c) IN-0.75: 0.75 g IN/d on the 1st week, 1.5 g IN/d on the 2nd week, 2.25 g IN/d on the 3rd week and 3 g IN/d on the 4th week. Starting at 28 d of age, piglets were weaned and received a post-weaning diet without inulin during the following 3 weeks. At both 28 d and 49 d of age, piglets were euthanised for sampling. Piglets of group IN-0.5 had the highest body weight starting from the 3rd week (p < 0.05), concomitant with the highest villus height and the ratio of villus height/crypt depth in the jejunum and ileum on both sampling days (p < 0.05). At 28 d of age, an increased concentration of propionate, iso-butyrate or total short chain fatty acids was observed between treatment IN-0.5 and the other groups in the caecum or colon (p < 0.05). Moreover, the relative abundance of Escherichia coli (p = 0.05) and Enterobacteriaceae (p = 0.01) in colonic digesta were reduced in IN-0.5-treated piglets, and in both IN-supplemented groups, colonic interleukin-8, tumor necrosis factor-α and toll-like receptor-4 mRNA abundance were decreased compared to the CON group (p < 0.05). However, at 49 d of age, most of these differences disappeared. In conclusion, treatment IN-0.5 improved during the suckling period of piglets development of intestine, but these beneficial effects were not lasting after weaning, when IN supplementation was terminated. Treatment IN-0.75, however, did not display a prebiotic effect.

Alpha-Ketoglutarate in Low-Protein Diets for Growing Pigs: Effects on Cecal Microbial Communities and Parameters of Microbial Metabolism.

Alpha-ketoglutarate (AKG), a critical molecule in the tricarboxylic acid cycle, is beneficial to intestinal functions. However, its influence on intestinal microbiota and metabolism is not fully understood. We investigated the effects of a low-protein (LP) diet supplemented with AKG on cecal microbial communities and the parameters of microbial metabolism in growing pigs. Twenty-seven young pigs (Large White × Landrace) with an average initial body weight of 11.96 ± 0.18 kg were randomly allotted into three groups (n = 9): a normal protein (NP) diet containing 20% crude protein (CP); LP diet formulated with 17% CP (LP diet); or LP diet supplemented with 10 g kg-1 of AKG (ALP diet). After a 35-day trial period, the digesta of the cecum were collected to analyze the concentrations of ammonia and short-chain fatty acids (SCFAs). We also performed a microbial analysis. Although no significant differences were found in performance among the diet groups, pigs fed the ALP diet had greater average daily gain (ADG) when compared with those in the LP group. Experimental diet did not affect cecal bacterial richness or diversity, as determined by Chao1 and ACE species richness measures and Shannon and Simpson indices, respectively. The predominant phyla Firmicutes, Bacteroidetes, and Proteobacteria increased in relative abundances in the cecum of pigs fed ALP diet. At the genus level, compared to the LP diet, the ALP diet significantly increased the abundances of Lachnospiraceae UCG-005, Lachnospiraceae NK4A136 group, Phascolarctobacterium and Parabacteroides, while decreased Vibrio and Maritalea. Pigs fed the ALP diet increased Oribacterium and Lachnoclostridium when compared with the NP diet. Non-metric multidimensional scaling analysis revealed that the distribution of microbiota at each group was distinctly clustered separately along principal coordinate. In addition, quantitative PCR revealed that the ALP diet was also associated with increases in the amounts of Bacteroides, Bifidobacterium, and Lactobacillus, but a decrease in the level of Escherichia coli. Compared with the NP diet, the ALP diet enhanced the concentrations of valerate and propionate. This ALP diet also increased the concentrations of valerate and isobutyrate when compared with the LP diet. Moreover, the ALP diet was linked with a significant decline in the concentration of ammonia in the cecum. These results indicate that a LP diet supplemented with AKG can alter the balance in microbial communities, increasing the population of SCFA-producing bacteria and the amounts of Bacteroides and Bifidobacterium, while reducing the counts of Escherichia coli and the amount of ammonia in the cecum.

Marked Response in Microbial Community and Metabolism in the Ileum and Cecum of Suckling Piglets After Early Antibiotics Exposure.

In modern swine husbandry systems, antibiotics have been used as growth promoters for piglets during suckling or weaning period. However, while early colonization of intestinal microbiota has been regarded crucial for the host’s later life performance and well-being, little is known about the impact of antibiotics on intestinal microbiota in suckling piglets. The present study aimed to investigate the effects of early antibiotics exposure on gut microbiota and microbial metabolism of suckling piglets. Sixteen litters of suckling piglets were fed a creep feed diet with (Antibiotic) or without (Control) antibiotics from postnatal days 7–23 (n = 8). The ileal and cecal digesta were obtained for microbial composition and microbial metabolites analysis. The results showed that the antibiotics significantly altered the bacterial community composition by decreasing (P < 0.05) the diversity and richness in the ileum. The antibiotics significantly reduced the abundance of Lactobacillus in both the ileum and cecum, increased the abundance of Streptococcus, unclassified Enterococcaceae, unclassified Fusobacteriales, and Corynebacterium in the ileum, and the abundance of unclassified Ruminococcaceae and unclassified Erysipelotrichaceae in the cecum. The antibiotics decreased (P < 0.05) ileal lactate concentration and cecal concentration of total short-chain fatty acids (SCFAs). But the antibiotics enhanced protein fermentation (P < 0.05) in the ileum and cecum, as ileal concentrations of putrescine and cadaverine, and cecal concentrations of isobutyrate, isovalerate, putrescine, cadaverine, spermine, and spermidine were significantly increased (P < 0.05). These results indicated that early antibiotics exposure significantly altered the microbial composition of suckling piglets toward a vulnerable and unhealthy gut environment. The findings provide a new insight on the antibiotics impact on neonates and may provide new framework for designing alternatives to the antibiotics toward a healthy practice for suckling piglets.

Conversion of organic waste into volatile fatty acids – The influence of process operating parameters

The objectives of this study were to investigate the effect of hydraulic retention time (HRT) and organic loading rate (OLR) on the volatile fatty acids (VFAs) production from cheese whey and sludge, and to find the relation between total volatile fatty acids (TVFAs) accumulation at different HRT and OLR and the corresponding bacterial community. The highest concentrations of butyrate (5.0 g COD/L), valerate (3.8 g COD/L), caproate (4.2 g COD/L) and heptate (0.8 g COD/L) were obtained from whey fermentation, where proportion of acetate increased with HRT shortening (from 8.3% to 83.5% for HRT of 20 to 1 day, respectively). The highest concentrations of acetate (1.6 g COD/L), propionate (2.9 g COD/L), iso-butyrate (0.8 g COD/L) and iso-valerate (1.8 g COD/L) were obtained from sludge fermentation, where proportion of acids was independent of HRT. Bacterial communities consisted mostly of the phyla Firmicutes, Cloacimonetes, Proteobacteria and uncultured bacterium clones. The bacterial community originating from the substrate was able to adapt to the applied bioreactor conditions and it had an immense impact on the process performance.