PSIV-9 Effective ruminal degradability of steam-flaked corn is influenced by flake density and starch retrogradation

The objective of this study was to evaluate in situ ruminal digestion characteristics of steam-flaked corn with large differences in starch availability (SA) using two different models: 1) increasing flake density and 2) exposure to 55°C temperatures to induce starch retrogradation. Five ruminally-cannulated steers (body weight = 390 ± 7.86 kg) were pen-fed a starter diet. In Exp. 1, sifted flakes with flake densities of 257, 296, 335, 373, and 412 g/L (SA: 87%, 76%, 66%, 43%, and 49%, respectively) were evaluated. In Exp. 2, three steam-flaked corn fractions were evaluated: flakes + fines (not sifted), sifted flakes (>4-mm), and sifted fines (< 4-mm). Feed fractions were stored for 3-d at either 23°C or 55°C (average SA across steam-flaked corn fractions: 53.3% and 25.5% respectively). Treatments of Exp. 2 were arranged with a 3 × 2 factorial. Both experiments were duplicated and analyzed as randomized complete block designs. In Exp. 1, the fractional rate of degradation linearly decreased (P < 0.001) and effective ruminal dry matter degradability (ERD) linearly decreased (P < 0.001) from 80.8% to 60.3% as flake density increased from 257 to 412 g/L. In Exp. 2, storage of steam-flaked corn samples at 55ºC for 3-d decreased (P < 0.001) the fractional rate of degradation and ERD by 38.6% and 21.7% across all feed fractions, respectively. Using data from Exp. 1 and 2, SA of sifted flakes was positively correlated (Pearson = 0.8435; R2 = 0.71; P < 0.001) to ERD. The results of the current study demonstrate that decreased SA resulting from starch retrogradation or increased flake density is associated with decreased ERD. Decreases in SA and ERD may indicate that increasing flake density or starch retrogradation could potentially alter the site of digestion in cattle, by increasing postruminal starch flows.

Effect of Alfalfa Hay Substitution by Raw Garlic Leaves on In vitro Gas Methane Production and Ruminal Fermentation

Background: The aim of present research was to evaluate under in vitro conditions, the effect of alfalfa hay substitution by raw garlic leaves on ruminal fermentation patterns and methane production in diets ruminants. Methods: Four treatments were evaluated: (T1) alfalfa hay (50%); (T2) alfalfa hay (33%) + raw garlic leaves (17%); (T3) alfalfa hay (17%) + raw garlic leaves (33%) and (T4) raw garlic leaves (50%). Result: The highest values of fractional rate of gas production (kd), ammonia-nitrogen (NH3-N), propionate and microbial biomass synthesis (MBS) was recorded in T4 and the lowest in T1 (P less than 0.05). In contrast, the highest methane production was recorded in T1 and the lowest in T4 (P less than 0.05). It was concluded that the substitution of alfalfa hay by raw garlic leaves in diet with 50% roughages and 50% concentrate result in an improvement in vitro rumen fermentation pattern and decreases the methane production.

Photodissociation branching ratios of 12C16O from 110 500 to 113 045 cm−1: first observation of the C(1S) channel

Carbon monoxide (CO) is one of the most abundant molecular species in comets. Its photodissociation by the solar radiation in the vacuum ultraviolet (VUV) region produces excited atomic fragments C(1D), C(1S), and O(1D), which radiate at characteristic wavelengths when they decay to lower states. The fractional rate constants for generating these fragments from CO photodissociation under the entire range of the solar radiation field are key input values in modelling the observed atomic emission intensities from comets. In this study, the branching ratios of the four lowest dissociation channels C(3P)+O(3P), C(1D)+O(3P), C(3P)+O(1D), and C(1S)+O(3P) of the 12C16O photodissociation are measured in the VUV energy range between the threshold of producing the C(1S)+O(3P) channel (~110 500 cm−1) and the ionisation energy (IE) of 12C16O (~113 045 cm−1). We measured these ratios using the VUV time-slice velocity-map ion imaging apparatus. We observe a number of high Rydberg states in the aforementioned energy range, with most of them mainly producing ground C(3P) and O(3P) atomic fragments, and only a few of them producing a significant amount of excited C(1D) or O(1D) fragments. We also observe the excited C(1S) fragment from CO photodissociation and measured its branching ratio for the first time. Based on the photodissociation branching ratios measured in the current and previous studies, we are able to estimate the relative percentages of the excited atomic fragments C(1D), C(1S), and O(1D) from the solar photolysis of 12C16O below its IE. We discuss the implications for the photochemical modelling of the CO-dominated comet C/2016 R2 (Pan-STARRS).

PSIX-17 Investigation of rumen starch and protein degradation kinetics in relation to corn processed by super-conditioned pelleting, extruding and puffing

The objective of this study was to investigate the rumen dry matter (DM), starch and protein degradation kinetics of an Iranian corn grain (single crass 702) processed using different thermal processing methods including 1) grinding (G, 2mm), 2) super-conditioned pelleting (SCP; moisture 20%, retention time 6 min and conditioning temperature 95°C), 3) puffing (PUF; puffing temperature 200°C, hot air velocity 25 m/s, feed rate 100 g/m) and 4) extruding (EX; moisture 20%, temperature of melting zone 75°C and die zone 125°C and time 150s). Three lactating Holstein cows fitted with a ruminal cannula were used. Samples were incubated into the rumen for 2, 4, 8, 12, 24, and 48 h. Rumen degradation kinetics were fitted based on equations. Data were analyzed by GLM procedure of SAS (P < 0.05) using a completely randomized design with 6 replications for every treatment. Rapidly soluble fraction (a) and fractional rate constant (c) of DM were higher (P < 0.01) in PUF and EX corns than SCP. The lowest (P < 0.05) slowly degradable fraction (b) of DM was found in SCP. The highest (P < 0.01) effective rumen degradability of DM (ERDM), starch (ERDS) and protein (ERDP) were observed in the EX, followed by PUF, SCP and G corns. Fraction a of starch and protein was significantly greater (P < 0.01) in EX, PUF and SCP than G. The rate of degradability (c) of starch, DM and protein in EX and PUF were similar and higher (P < 0.01) than SCP and G, but c for starch in EX was greater (P < 0.01) than PUF and fallowed by SCP and G corns. In conclusion, the super-conditioning of corn as a new method of corn processing increased rapidly soluble fraction starch similar to PUF and EX corns and effective rumen degradability of starch was significantly increased in SCP corn.

Possibilities of modern drug correction of metabolic syndrome: the role of bile acids

After the discovery of the method of synthesis of ursodeoxycholic acid (UDCA) and the publication of evidence confirming its ability to reduce the lithogenic properties of bile, active clinical use of UDCA began around the world. This drug, in addition to the proven choleretic, cytoprotective, litholytic, anti-apoptotic effects, has a signaling activity that allows UDCA to influence metabolic syndrome components such as hyperglycemia, hypercholesterolemia. Under the influence of UDCA, FXR is activated in the liver, which leads to an increase in the activity of glycogen synthase and decrease in the level of glycaemia. Another mechanism by which UDCA affects glycaemia is mediated by the activation of the TGR5 membrane receptor under the influence of this bile acid, as well as the release of insulin from pancreatic β-cells and decrease in postprandial glycaemia. When taking UDCA, the concentration of glycosylated hemoglobin, insulin in the blood plasma decreases the effects of insulin resistance decrease. UDCA has a beneficial effect on the vascular wall, reducing the severity of atherosclerotic lesions and normalizing the average thickness of the intima-media complex. UDCA improves lipid metabolism by regulating the activity of the AKT/ mTOR-signaling pathway, reduces the synthesis of cholesterol, and decreases the fractional rate of cholesterol synthesis and the fractional rate of triglyceride synthesis. It is proved that UDCA administration is accompanied by a drop in the level of total cholesterol and cholesterol of low-density lipoproteins. Normalization of the metabolism of glucose, triglycerides, cholesterol and the insulin-signaling pathway under the influence of bile acids is the basis for the use of UDCA for the correction of metabolic syndrome, as well as its hepatological manifestations - NAFLD.

PSVIII-7 In vitro fermentation of different dietary fibers selectively changed sow gut microbiota composition

In vitro fermentation experiments with modified starch 1 (MS1), modified starch 2 (MS2), guar gum (GG), xanthan gum (XG), konjac flour (KF), wheat brain (WB), and inulin (I) were conducted for 48 h to investigate the effects on gilt gut microbiota. Fecal examples were obtained from three gilts; the fermentation kinetics parameters were analysed in Logistic-Exponential (LE) model such as the final asymptotic gas volume (Vf, ml/g), initial fractional rate of degradation at t-value=0 (FDR0, h-1), fractional rate of gas production at particular time (k, h-1) and half-time to asymptote (T1/2, h). Samples were collected after fermentation for short chain fatty acids (SCFAs) and 16S rDNA microbial analysis. MS1, MS2, and I had the highest Vf (P < 0.01). The k of GG and I were significant higher (P < 0.01). FDR0 of MS2, GG, and I were the lowest following KF, MS1, WB, and XG, successively (P < 0.01). T1/2 of MS1, KF, WB, and GG were lower (P < 0.01). MS1, MS2, and GG produced more acetate (P < 0.05) and total SCFAs (P < 0.01), and butyrate produced by MS2 was significant higher (P < 0.01). The microbiota composition changed dramatically after fermentation, decreasing bacteria abundance and alpha-diversity (P < 0.01). The relative abundance of phyla Firmicutes and Bacteroidetes decreased, while phyla Spirochaetes, Proteobacteria, Kiritimatiellaeota, and Fusobacteria were selectively promoted by DF. The LEfSe analysis showed Proteobacteria, Gammaproteobacteria, and Aeromonadales were enriched in MS1 treatment; Clostridiales, Clostridia, and Anaerosporobacter were enriched in MS2 treatment; Bacteroidales, Bacteroidia, and Bacteroidetes were enriched in GG treatment; Ruminococcaceae and Ruminococcaceae_UCG_013 were enriched in XG treatment; Lachnospiraceae, Lachnospiraceae_NK4A136_group, and Ruminiclostridium were enriched in KF treatment; Enterobacteriales, Enterobacteriaceae, and Lactobacillales, were enriched in I treatment. In conclusion, different type of DFs may play a specific role in gilt gut microbiota changing and composition.

133 Porcine in vitro degradation and fermentation characteristics of heat-pretreated and multi-enzyme-supplemented soybean hulls

A study was conducted to determine effects of pretreating and supplementing soybean hulls with multi-enzyme on porcine in vitro digestion and fermentation characteristics. Treatments were untreated and heat-pretreated (160 °C and 70 psi for 20 min) soybean hulls without or with multi-enzyme in a 2 × 2 factorial arrangement. The multi-enzyme supplied 2,800 U of cellulase, 1,800 U of pectinase, 400 U of mannanase, 1,000 U of xylanase, 600 U of glucanase, and 200 U of protease/kilogram of feedstuff. Feedstuffs were subjected to in vitro digestion with porcine pepsin and pancreatin, followed by in vitro fermentation for 72 h. Accumulated gas production was recorded and modeled to estimate kinetics of gas production. On DM basis, untreated and pretreated soybean hulls contained 10.4 and 10.6% CP, and 63.2 and 49.5% ADF, respectively. Pretreatment and multi-enzyme supplementation did not interact on in vitro digestibility of DM (IVDDM). Untreated and pretreated soybean hulls did not differ in IVDDM (24.8 vs. 25.7%). Multi-enzyme increased (P < 0.05) IVDDM of soybean hulls by a mean of 45.5%. Pretreatment and multi-enzyme unaffected total gas production. Pretreatment and multi-enzyme interacted (P < 0.05) on fractional rate of degradation such that the fractional rate of degradation for pretreated soybean hulls was greater (P < 0.05) than that of untreated soybean hulls when soybean hulls were supplemented with multi-enzyme (0.045 vs. 0.062 h-1), but not when soybean hulls were unsupplemented with multi-enzyme (0.053 vs. 0.059 h-1). In conclusion, multi-enzyme supplementation increased IVDDM, implying that the multi-enzyme used in the study can be used to enhance utilization of soybean hulls. Heat pretreatment increased the rate of fermentation of multi-enzyme-supplemented soybean hulls, implying that the rate of fermentation of soybean hulls in the hindgut of pigs can be enhanced by a combination of heat pretreatment and multi-enzyme supplementation.

Effects of Gas Production Recording System and Pig Fecal Inoculum Volume on Kinetics and Variation of In Vitro Fermentation using Corn Distiller’s Dried Grains with Solubles and Soybean Hulls

An experiment was conducted to investigate the effect of inoculum volume (IV), substrate quantity, and the use of a manual or automated gas production (GP) recording system for in vitro determinations of fermentation of corn distillers dried grains with solubles (cDDGS) and soybean hulls (SBH). A 2 × 2 × 2 factorial arrangement of treatments was used and included the factors of (1) ingredients (cDDGS or SBH), (2) inoculum volume and substrate quantity (IV30 = 0.2 g substrate + 30 mL inoculum or IV75 = 0.5 g substrate + 75 mL inoculum), and (3) GP recording system (MRS = manual recording system or ARS = automated recording system). Feed ingredient samples were pre-treated with pepsin and pancreatin, and the hydrolyzed residues were subsequently incubated with fresh pig feces in a buffered mineral solution. The GP recording was monitored for 72 h, and the kinetics were estimated by fitting data using an exponential model. Compared with SBH, cDDGS yielded less (p < 0.01) maximal gas production (Gf), required more time (p < 0.02) to achieve half gas accumulation (T/2), and had less (p < 0.01) fractional rate of degradation (µ) and in vitro fermentability of dry matter (IVDMF). Using the ARS resulted in less IVDMF (p < 0.01) compared with MRS (79.0% vs. 81.2%, respectively). Interactions were observed between GP recording system and inoculum volume and substrate quantity for Gf (p < 0.04), µ (p < 0.01), and T/2 (p < 0.04) which implies that increasing inoculum volume and substrate quantity resulted in decreased Gf (332 mL/g from IV30 vs. 256 mL/g from IV75), µ (0.05 from IV30 vs. 0.04 from IV75), and T/2 (34 h for IV30 vs. 25 h for IV75) when recorded with ARS but not MRS. However, the recorded cumulative GP at 72 h was not influenced by the inoculum volume nor recording system. The precision of Gf (as measured by the coefficient of variation of Gf) tended to increase for IV30 compared with IV75 (p < 0.10), indicating that using larger inoculum volume and substrate quantity (IV75) reduced within batch variation in GP kinetics. Consequently, both systems showed comparable results in GP kinetics, but considering convenience and achievement of consistency, 75 mL of inoculum volume with 0.5 g substrate is recommended for ARS.