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Summary Production of the high‐value carotenoid astaxanthin, which is widely used in food and feed due to its strong antioxidant activity and colour, is less efficient in cereals than in model plants. Here, we report a new strategy for expressing β‐carotene ketolase and hydroxylase genes from algae, yeasts and flowering plants in the whole seed using a seed‐specific bidirectional promoter. Engineered maize events were backcrossed to inbred maize lines with yellow endosperm to generate progenies that accumulate astaxanthin from 47.76 to 111.82 mg/kg DW in seeds, and the maximum level is approximately sixfold higher than those in previous reports (16.2–16.8 mg/kg DW) in cereals. A feeding trial with laying hens indicated that they could take up astaxanthin from the maize and accumulate it in egg yolks (12.10–14.15 mg/kg) without affecting egg production and quality, as observed using astaxanthin from Haematococcus pluvialis. Storage stability evaluation analysis showed that the optimal conditions for long‐term storage of astaxanthin‐rich maize are at 4 °C in the dark. This study shows that co‐expressing of functional genes driven by seed‐specific bidirectional promoter could dramatically boost astaxanthin biosynthesis in every parts of kernel including embryo, aleurone layer and starch endosperm other than previous reports in the starch endosperm only. And the staple crop maize could serve as a cost‐effective plant factory for reliably producing astaxanthin.

This study evaluated different strategies of forage inclusion for finishing beef cattle and their impact on performance, carcass quality, and liver abscesses. Steers (n=360, 400±29 kg) were blocked by weight and randomly assigned to one of four treatments (15 steers/pen, 6 pens/treatment) in a complete randomized experiment. Treatments were: 1) positive control (+CON) fed a diet (7.5% forage on a diet DM basis) with tylosin (11 mg/kg); 2) negative control (–CON; control diet without tylosin); 3) a diet where forage concentration decreased (DECR) every 42 d and was static for the last 84 d (forage represented 15%, 9%, 3%, and 3% of DM, respectively) without tylosin; and 4) a diet where forage concentration increased (INCR), the inverse of the DECR without tylosin. There were no differences in initial BW, DMI, and G:F (P≥0.38). The INCR steers had lower ADG (1.63 vs. 1.74 kg, P=0.05), total BW gain (287 vs. 306 kg, P=0.05), and tended to have lower final BW and carcass weight (P=0.07) compared to +CON, with no differences from the other treatments. No differences were observed for carcass dressing percentage, ribeye area, marbling scores, and quality grades (P≥0.41). Backfat thickness and yield score were lower for INCR steers (14.2 mm and 3.42) compared to –CON (16.9 mm and 3.82, P=0.04), while other treatments did not differ. There was no difference for the percentage of steers with liver abscess or severe abscess (A+; P≥0.17). However, the percentage of steers with minor liver abscesses (A) was numerically less for +CON (51.8%) and DECR (51.8%) compared to –CON (62.2%) and INCR (64.3%, P=0.055). This suggests that higher dietary concentrations of forage in the beginning stages of finishing, with a subsequent decline thereafter has the potential to decrease the proportion of minor liver abscesses, similar to the inclusion of tylosin in a high-grain diet, without impacting growth performance or carcass quality.

Background The objectives of this study were to determine the effect of commercial slow-release urea (SRU) on in vitro fermentation characteristics, nutrient digestibility, gas production, microbial protein synthesis and bacterial community using a rumen simulation technique (RUSITEC). The experiment was a completely randomized design with four treatments and four replications of each treatment. Treatments were: control diet (no SRU addition), control diet plus 0.28% SRU (U28), or plus 0.56% SRU (U56), and control diet that was modified substituting a part of soybean meal equivalent to 0.35% SRU (MU35; dry matter [DM] basis). The experiment consisted of 8 d of adaptation and 7 d of data and sample collection. Rumen inoculum was obtained from three ruminally fistulated Angus cows fed the same diet to the substrate incubated. Results Digestibility of DM, organic matter (OM), crude protein (CP), fibre and starch was not affected, but daily production of gas (P P P P P P P P P P Rikenellaceae and Prevotellaceae in feed particle-associated bacteria, and the abundance of Roseburia in liquid associate bacteria was greater (P Conclusions Supplementation of a dairy cow diet with SRU showed potential of increase in ammonia N concentration and microbial protein production, and change fermentation pattern to more acetate production. Adding SRU in dairy cow diet also showed beneficial effect on improving digestibility of OM and fibre. The results suggest that SRU can partially substitute soybean meal in dairy cow diet to increase microbial protein production without impairing rumen fermentation.

Physically effective neutral detergent fiber (peNDF) content of dairy cow diets was modified by varying the theoretical chop length of alfalfa silage and forage:concentrate (F:C) ratio, and effects on nutrient intakes, ruminal fermentation, site and extent of digestion, microbial protein synthesis, and milk production were evaluated. Estimates of dietary peNDF contents were compared with recommendations, and predictions of ruminal pH from peNDF and the recently developed physically adjusted neutral detergent fiber (paNDF) system were compared with observed pH. The experiment was designed as a triple 4 × 4 Latin square using 12 mid-lactating dairy cows with 4 intact, 4 ruminally cannulated, and 4 ruminally and duodenally cannulated cows. Site and extent of digestion and microbial protein synthesis were measured in a single 4 × 4 Latin square. Treatments were a 2 × 2 factorial arrangement; 2 forage particle lengths (FPL) of alfalfa silage (short and long) were combined with low (35:65) and high (60:40) F:C ratios [dry matter (DM) basis]. The peNDF contents were determined by multiplying the proportion (DM basis) of total mixed ration retained on 2 (8 and 19 mm; peNDF8.0) or 3 (1.18, 8, and 19 mm; peNDF1.18) sieves of the Penn State Particle Separator by the neutral detergent fiber content of the diet. The dietary peNDF contents ranged from 10.7 to 17.5% for peNDF8.0 or from 23.1 to 28.2% for peNDF1.18. Interactions between F:C ratio and FPL content were few. Increasing peNDF content of diets by increasing F:C ratio decreased DM intake, milk yield, and milk protein yield, whereas apparent total-tract DM digestibility and milk efficiency improved. Increasing F:C ratio improved ruminal pH status but decreased total volatile fatty acid concentration and microbial protein synthesis. Increasing peNDF content of diets via dietary FPL increased mean ruminal pH, but did not affect DM intake, total-tract digestibility, or milk production. The results indicate that feeding dairy cows a low F:C diet helps increase DM intake, milk production, and microbial protein synthesis, but may adversely affect feed digestibility and milk efficiency due to increased risk of subacute ruminal acidosis. Increased FPL improved ruminal pH status, but had minimal effects on feed intake, ruminal fermentation, nutrient digestibility, and milk production. The results indicate a trade-off between reducing the risk of subacute ruminal acidosis and maximizing ruminal fermentation, feed digestibility, and milk production of dairy cows. The paNDF model showed improvement in the predictability of ruminal pH over the peNDF model, but the accuracy of predictions varied depending upon the diet and ruminal fermentation variables considered in the equations.

Red osier dogwood (ROD) is native shrub plant in Canada and rich in bioactive compounds. The objective of this study was to evaluate the effects of ROD extract supplementation in a high-forage (HF) diet on gas production (GP), dry matter (DM) disappearance (DMD) and fermentation characteristics in batch cultures with varying media pH. The study was a completely randomized design with 4 levels of ROD extract (0, 1, 3 and 5% of substrate) × 2 media pH (5.8 and 6.5) factorial arrangement. The study was conducted in three replicate experiments. Substrate contained 60% barley silage and 40% barley concentrate (DM basis). Inoculum was obtained from 2 ruminally fistulated beef heifers offered the HF diet. Substrate (0.5 g DM) ground (1 mm) was incubated for 48 h in a culture bottle. Data were analyzed using Mixed procedure of SAS with fixed effects of treatments and random effect of experiment. There was no interaction between media pH and level of ROD on GP, DMD and fermentation characteristics. Increased media pH (5.8 vs. 6.5) increased (P < 0.01) GP (averaged 164 vs. 275 ml/g substrate), DMD (50.6 vs. 60.6%), and total VFA production (63 vs. 71 mM). Increasing ROD extract levels did not affect GP but linearly (P = 0.05) decreased DMD from 62.1 to 58.9% at pH 6.5. Although total VFA production was not affected, increasing ROD extract linearly (P < 0.01) increased the proportion of acetate (47.9 to 49.7%) and propionate (20.5 to 22.3%) at pH 5.8; whereas at pH 6.5, acetate to propionate ratio quadratically (P = 0.04) changed to be lower with 3% ROD extract (2.08) than other treatments (2.21). These results indicated that supplementation of HF diet with ROD extract may improve fibre digestion at low media pH, and improve fermentation efficiency at high media pH.

The objective of this study was to evaluate the effects of slow-release urea (SRU) on gas production, fermentation parameters, nutrient digestibility, and microbial protein synthesis using artificial rumen system. The experiment was a completely randomized design with four treatments and four replications of each treatment. The treatments were control diet (no SRU), control diet supplemented with 0.28% (U28), 0.56% SRU (U56) or control diet that was added by 1.5% more corn grain and substituted with 0.35% SRU for 1.85% soybean meal (U35-SBM). The diets were formulated to be isoenergetic (1.71 NEL Mcal/kg), but protein concentration was lower (15.48 vs. 16.24%) and starch concentration was higher (28.2 vs. 27.1%) with U35-SBM than other three treatments. Experimental period consisted of 8 d of adaptation and 7 d of sampling. Rumen inoculum was obtained from three ruminally fistulated Angus cows fed the same diet to the substrate incubated. Gas production (L/d) was lower (P = 0.02) with U35-SBM (1.51) than control (1.79) or U28 (1.92); however, methane production was not affected by treatments (average, 47 mg/d). Dry matter digestibility was greater (P < 0.01) with U35-SBM (78.5%) than other treatments (74.6%), which had no differences in DM digestibility. Total volatile fatty acid (VFA) production did not differ among treatments (average, 53.1 mmol/d), but increasing SRU supplementation linearly (P < 0.01) decreased molar proportion of propionate from 27.0 to 25.7% and linearly (P < 0.01) increased acetate to propionate ratio from 1.69 to 1.78. The ammonia nitrogen (N) linearly (P < 0.01) increased from 7.70 to 10.25 mmol/L with increasing SRU addition. Microbial protein synthesis was greater (P = 0.03) with SRU treatments (average, 83.9 mg N/d) than control (78.9 mg N/d). The present results demonstrated the benefits to add the SRU in dairy cow diet for improving ruminal digestibility and microbial protein synthesis.

The objectives of this study were to assess the effects of Saccharomyces cerevisiae fermentation products (SCFP; NaturSafe, SCFPns; and Original XPC, XPC; Diamond V) on growth performance, carcass traits, immune response, and antimicrobial resistance in beef steers fed high-grain diets. Ninety Angus steers (initial body weight [BW], 533 ± 9.8 kg) were assigned to a randomized complete design with 6 treatments (n = 15/treatment): 1) control, 2) low (12 g SCFPns·steer−1·d−1), 3) medium (15 g SCFPns·steer−1·d−1), 4) high SCFP (18 g SCFPns·steer−1·d−1), 5) encapsulated XPC (eXPC; 7 g XPC·steer−1·d−1 encapsulated with 9 g capsule material), and 6) antibiotics (ANT; 330 mg monensin + 110 mg tylosin·steer−1·d−1). Steers were fed ad libitum a diet containing 10% barley silage and 90% barley grain concentrate mix (dry matter basis) for 105 d. Increasing SCFPns tended (P < 0.09) to linearly increase feed efficiency. Average daily gain (ADG) tended (P < 0.10) to be greater in steers supplemented with eXPC than control. The SCFPns also tended (P < 0.10) to linearly increase marbling score. Proportion of severely abscessed livers tended (P < 0.10) to be lower in steers supplemented with medium and high SCFPns, eXPC, or ANT. A treatment × days on feed interaction were noticed (P < 0.01) for blood glucose, blood urea nitrogen (BUN), and acute phase proteins. The concentration of blood glucose responded quadratically (P < 0.05) on days 28 and 56, whereas BUN linearly (P < 0.01) increased on day 105 with increasing SCFPns dose. The SCFPns linearly increased haptoglobin (P < 0.03) and serum amyloid A (SAA;P < 0.05) concentrations on day 105, and lipopolysaccharide binding protein (LBP;P < 0.01) on days 56 and 105. The percentage of erythromycin-resistant and erythromycin + tetracycline-resistant enterococci was greater (P < 0.05) with ANT than control, SCFPns, and eXPC, whereas no difference was observed among control, SCFPns, and eXPC. No treatment effect was detected on the percentage of tetracycline-resistant enterococci. These results indicate that feeding SCFPns and eXPC was beneficial in improving ADG, feed efficiency and decreasing liver abscesses in a manner comparable to ANT. Unlike antibiotics, SCFPns or eXPC did not increase antimicrobial resistance. Both SCFPns and eXPC are potential alternatives to in-feed antibiotics.

A metabolism study was conducted using 8 ruminal cannulated beef heifers to investigate the effects of a recombinant fibrolytic enzyme (RFE; xylanase XYL10C) selected specifically for forage-fed ruminants on ruminal pH, fermentation, nitrogen balance, and total tract digestibility of heifers. The experiment was a cross-over design with 2 treatments and 2 periods. The 2 treatments were a basal diet containing 60% barley silage, 30% barley straw, and 10% supplement (DM basis) without (control) or with RFE. The enzyme was sprayed onto the barley straw at a rate of 6.6 × 104 IU·kg−1 DM 24 h before feeding. Each period comprised 2 wk of diet adaptation and 1 wk of sampling and data collection. Feed intake and total tract digestibility of DM, OM, NDF, and ADF were unaffected by RFE. Ruminal pH including mean, minimum, maximum, and duration pH

This study evaluated the effects of undigested neutral detergent fiber (uNDF) concentration and forage inclusion (FI) rate on dry matter (DM) intake, ruminal pH, reticular contractions, and gastrointestinal permeability for finishing beef cattle. Five ruminally cannulated Hereford′Simmental heifers (699±69.1 kg) were used in an incomplete 6×6 Latin square (26-d periods) with a 2×3 factorial treatment arrangement. Barley grain-based diets were formulated using barley silage or wheat straw to provide low or high uNDF (7.1 vs. 8.5% DM) with forage proportions of 5, 10, or 15% of dietary DM. Dry matter intake (P ≥ 0.10) and eating time (P ≥ 0.13) were not affected by uNDF, FI, or uNDF′FI. With low uNDF diets, increasing FI numerically (P = 0.02) increased rumination time (min/d); while, with high uNDF diets, rumination time increased with 5 to 10% FI, but not thereafter (P = 0.03). Mean ruminal pH was not affected by uNDF (6.17 vs. 6.19; P = 0.08), but increased with increasing FI (6.04b, 6.23a, and 6.28a; P = 0.02). Duration of ruminal pH < 5.5 was not affected by uNDF but tended (P = 0.07) to be reduced with increasing FI. High uNDF diet tended to increase the frequency of reticular contractions (1.43 vs. 1.51 contractions/min; P = 0.07) but decreased the contraction duration (13.2 vs. 14.1 sec; P = 0.04). Increasing FI increased contraction frequency (1.39b, 1.50a, and 1.53a contractions/min; P = 0.03) and tended to reduce contraction duration as forage increased from 5 to 10 and 15% (14.3, 13.1, and 13.6 sec; P = 0.07). Feeding high uNDF decreased (P = 0.05) permeability of the gastrointestinal tract based on the appearance of Cr-EDTA in urine following an intra-ruminal dose. Increasing FI tended to reduce gastrointestinal tract permeability (P = 0.06). Limited interactions indicate that uNDF and FI act independently suggesting that increasing dietary uNDF, without increasing FI rate, can stimulate frequency of reticulo-ruminal contractions and reduce gastrointestinal permeability for finishing cattle.

The uniqueness of wheat-based distiller grain (wDG) with high protein and digestible fibre gives great feeding opportunities for cattle as energy, protein or fiber source. This abstract summarizes recent research findings on the use of wDG in beef cattle diets. For growing beef cattle, steers fed diets (forage:concentrate, 55:45) with increasing replacement of barley grain with wDG from 0, 8, 16, 24 to 32% (DM basis) linearly (P < 0.01) increased average daily gain (ADG) from 1.09 to 1.28 kg/d and DM intake (DMI) from 7.26 to 7.94 kg/d without affecting gain:feed (0.158). By comparing protein source of canola meal and corn DG in diets containing 60% of silage and 40% of barley grain, steers fed wDG diet had similar ADG (1.46 kg/d) with corn DG (1.51 kg/d), and had no differences in gain:feed (0.178) with canola meal (0.183). For finishing beef cattle, with increasing wDG from 10, 20 to 40% in the place of barley grain of finishing diets, the DMI linearly (P < 0.01) increased from 10.2 to 10.9 kg/d, whereas, the gain:feed linearly (P < 0.01) decreased from 0.172 to 0.159 without altering the ADG (1.74 kg/d). The wDG was also suggested to be fed as fiber source to replace roughage in finishing diet. Entirely substitution of wDG for roughage of finishing diet decreased (P < 0.01) ruminal pH from 5.95 to 5.75 of beef heifers; however, the ADG and gain:feed of steers were not affected. The results suggested that although substitution of wDG for roughage in finishing diets may increase the incidence of ruminal acidosis, this outcome does not appear to adversely impact the performance of the cattle. The wDG can be successfully incorporated to substitute a portion of grain or roughage within growing and finishing diets with minimal or no adverse impact on cattle growth performance.

This study evaluated the effects of silage source, physically effective neutral detergent fiber (peNDF), and undigested neutral detergent fiber (uNDF) concentrations on eating behavior, ruminal pH, and reticular contractions for finishing beef heifers. Six Hereford′Simmental heifers (579±51.2 kg) were used in a replicated 6×6 Latin square (21-d periods) balanced for carry-over effects with 2×2 + 2 factorial treatment arrangement. Barley grain-based diets included barley (BarS) or wheat silage (WhS) at 10% of dietary DM. Silages were harvested at two chop lengths to yield low (LpeNDF) vs. high peNDF (HpeNDF) silage. For both BarS and WhS, chopped wheat straw was included (5% of DM) by replacing an equal proportion of LpeNDF silages to evaluate low vs. high uNDF (7.3 vs. 8.2% dietary DM) concentrations. Heifers fed HpeNDF WhS had greater DMI (silage′peNDF; P < 0.01) than those fed HpeNDF BarS, but DMI did not differ for LpeNDF treatments. Ruminating and eating time increased for heifers fed HpeNDF WhS relative to LpeNDF WhS, but were not different for BarS (silage′peNDF; P ≤ 0.02). Increasing uNDF increased eating and ruminating times for heifers fed WhS, but not BarS (silage′uNDF; P ≤ 0.03). Mean ruminal pH averaged 5.97 and was not affected by silage, peNDF, uNDF, or the interactions (P ≥ 0.12). Feeding BarS increased the duration (384 vs. 256 min/d; P = 0.02) and area (84.5 vs. 43.8 pH×min/d; P = 0.02) that pH was < 5.5 relative to WhS. Increasing peNDF numerically reduced the frequency of reticular contractions when fed BarS but numerically increased them when fed WhS (silage′peNDF; P < 0.01). Reticular contractions were not affected by dietary uNDF concentration (P ≥ 0.13). These data highlight that at a constant inclusion rate, silage source and chop length interact to affect DMI, eating behavior, ruminal pH, and reticular motility indicating the need to account for silage type, peNDF, and uNDF in diet formulation for finishing cattle.

The objective of this study was to investigate the effects of processing index (PI) of barley grain and dietary undigested neutral detergent fiber (uNDF) concentration on dry matter (DM) intake, chewing activity, ruminal pH and fermentation characteristics, total tract digestibility, gastrointestinal barrier function, and blood metabolites of finishing beef heifers. The PI was measured as the density after processing expressed as a percentage of the density before processing, and a smaller PI equates to a more extensively processed. Six ruminally cannulated heifers (average body weight, 715 ± 29 kg) were used in a 6 × 6 Latin square design with three PI (65%, 75%, and 85%) × 2 uNDF concentration (low and high; 4.6% vs. 5.6% of DM) factorial arrangement. The heifers were fed ad libitum a total mixed ration consisting of 10% barley silage (low uNDF), or 5% silage and 5% straw (high uNDF), 87% dry-rolled barley grain, and 3% mineral and vitamin supplements. Interactions (P < 0.01) of PI × uNDF were observed for DM intake, ruminating and total chewing time, and DM digestibility in the total digestive tract. Intake of DM, organic matter (OM), starch, and crude protein (CP) did not differ (P > 0.14) between low and high uNDF diets, but intakes of NDF and acid detergent fiber were greater (P = 0.01) for high uNDF diets regardless of barley PI. Heifers fed high uNDF diets had longer (P = 0.05) eating times (min/d or min/kg DM) and tended (P = 0.10) to have longer total chewing times (min/kg DM) than those fed low uNDF diets. Additionally, heifers sorted (P = 0.01) against long particles (>19 mm) for high uNDF diets but not for low uNDF diets. Altering PI of barley grain did not affect (P > 0.12) total volatile fatty acid (VFA) concentration, molar percentages of individual VFA, or duration of ruminal pH < 5.8 and

The objective of this study was to investigate the effects of processing index (PI, weight after processing/weight before processing × 100) of barley grain and dietary undegradable fiber (uNDF, 240 h of incubation in rumen) concentration on DM intake (DMI), ruminal pH and fermentation characteristics of finishing beef cattle. Six ruminally cannulated beef heifers (BW, 715 ± 29 kg) were used in a 6 × 6 Latin square design with 3 PI (65, 75 and 85%; fine, medium, coarse, respectively) × 2 uNDF concentrations (low and high; 4.6 vs. 5.6% of DM) factorial arrangement. Heifers were fed ad libitum a diet consisting of 10% barley silage (low uNDF), or 5% silage and 5% straw (high uNDF), 87% dry-rolled barley, and 3% vitamin and mineral supplements. An interaction of PI × uNDF was observed (P < 0.01) for DMI, but not for mean or duration of rumen pH < 5.8 or < 5.6 over a 24-h period. The DMI (kg/d) was greater (P < 0.05) for high (12.7) versus low (12.1) uNDF diets with 85% PI, with no difference in DMI (average, 12.1) between low and high uNDF diets with 65 or 75% PI. The duration of pH < 5.8 (14.6 versus 13.3 h) and pH < 5.6 (10.8 versus 8.6 h) reduced (P < 0.05) for high versus low uNDF diets. The PI did not affect total volatile fatty acid (tVFA) concentration or molar proportions of individual VFA, but the tVFA was less (172 and 162 mM; P < 0.01) and acetate proportion was greater (46.0 and 48.2%; P < 0.01) with high versus low uNDF. These results indicate that increasing dietary uNDF concentration is an effective strategy to improve ruminal pH status in finishing cattle, regardless of extent of grain processing, whereas minimizing the extent of grain processing did not reduce the risk of rumen acidosis.

Red osier dogwood (ROD) is an abundant native shrub plant in Canada and rich in phenolic compounds with antimicrobial properties. The objective of this study was to evaluate the effects of ROD extract supplementation on gas production (GP), DM disappearance (DMD) and fermentation characteristics in batch cultures with varying media pH. The study was a completely randomized design with 4 inclusion levels of ROD extract (0, 1, 3 and 5% of substrate) × 2 media pH (5.8 and 6.5) in a factorial arrangement. Substrate was a high-grain diet (HG) containing 10% barley silage and 90% barley-based concentrate mix (DM basis). Inoculum was obtained from 2 ruminally fistulated beef heifers offered the HG diet. Substrate (0.5 g DM) ground through a 1-mm sieve was incubated for 24 h in 3 replications including each combination of treatments. There was no interaction between media pH and inclusion level of ROD on GP, DMD and fermentation variables. Increased media pH (5.8 vs 6.5) increased (P < 0.01) GP (averaged 198 vs. 389 ml/g substrate), DMD (averaged 51.3 vs. 64.6%), and total volatile fatty acid production (averaged 74 vs. 83 mM). Increasing addition of ROD extract did not affect GP, but linearly (P < 0.05) decreased DMD from 56 to 46% at pH 5.8 and from 69 to 61% at pH 6.5. Increasing ROD extract linearly (P < 0.01) increased the proportion of acetate from 43 to 47% and 47 to 50% at pH 5.8 and 6.5, respectively. Acetate to propionate ratio increased from 1.68 to 1.93 and from 1.90 to 2.10 at pH 5.8 and 6.5, respectively. These results indicated that the decreased DMD along with increased acetate to propionate ratio with addition of ROD extract suggests ROD extract may be beneficial to HG fed cattle for reducing risk of rumen acidosis without negatively impacting fibre digestion.

Background Brewers’ spent grain (BSG) typically contains 20% – 29% crude protein (CP) with high concentrations of glutamine, proline and hydrophobic and non-polar amino acid, making it an ideal material for producing value-added products like bioactive peptides which have antioxidant properties. For this study, protein was extracted from BSG, hydrolyzed with 1% alcalase and flavourzyme, with the generated protein hydrolysates (AlcH and FlaH) showing antioxidant activities. This study evaluated the effects of AlcH and FlaH on gas production, ruminal fermentation characteristics, nutrient disappearance, microbial protein synthesis and microbial community using an artificial rumen system (RUSITEC) fed a high-grain diet. Results As compared to the control of grain only, supplementation of FlaH decreased (P P 3-N and decreased (P 2 production. Supplementation of FlaH decreased (P 4 in total gas and dissolved-CH4 (dCH4) in dissolved gas. Addition of monensin reduced (P 4 and H2 emissions. Total microbial nitrogen production was decreased (P P P P Prevotella, reduced Selenomonas, Shuttleworthia, Bifidobacterium and Dialister as compared to control; monensin reduced (P Prevotella but enhaced Succinivibrio. Conclusions The supplementation of FlaH in high-grain diets may potentially protect CP and starch from ruminal degradation, without adversely affecting fibre degradation and VFA profiles. It also showed promising effects on reducing CH4 production by suppressing H2 production. Protein enzymatic hydrolysates from BSG using flavourzyme showed potential application to high value-added bio-products.

Our previous study suggested that supplementation of high-grain diets with ruminally protected and non-protected active dried yeast (ADY) may potentially reduce manure pathogen excretion by feedlot cattle. We hypothesized that feeding ruminally protected ADY might change the fecal bacterial community of finishing cattle. The objective of this study was to investigate the effects of feeding ruminally protected and non-protected ADY to finishing beef steers on their fecal bacterial community. Fresh fecal samples were collected on day 56 from 50 steers fed one of five treatments: 1) control (no monensin, tylosin, or ADY), 2) antibiotics (ANT, 330 mg monensin + 110 mg tylosin·steer−1d−1), 3) ADY (1.5 g·steer−1d−1), 4) encapsulated ADY (EDY; 3 g·steer−1d−1), and 5) a mixture of ADY and EDY (MDY; 1.5 g ADY + 3 g EDY·steer−1d−1). Bacterial DNA was extracted from fecal samples and sequenced using a MiSeq high-throughput sequencing platform. A total number of 2,128,772 high-quality V4 16S rRNA sequences from 50 fecal samples were analyzed, and 1,424 operational taxonomic units (OTU) were detected based on 97% nucleotide sequence identity among reads, with 769 OTU shared across the five treatments. Alpha diversity indices, including species observed, Chao estimate, abundance-based coverage estimator, Shannon, Simpson, and coverage, did not differ among treatments, and principal coordinate analysis revealed a high similarity among treatments without independent distribution. Bacteroidetes and Firmicutes were dominant phyla in the fecal bacterial community for all treatments, with a tendency (P < 0.10) for greater relative abundance of Bacteroidetes but lesser Firmicutes with ANT, EDY, and MDY compared with control steers. Prevotella was the dominant genus in all treatments and steers supplemented with ANT, EDY, and MDY had greater (P < 0.05) relative abundance of Prevotella than control steers, but lesser (P < 0.03) relative abundance of Oscillospira. No differences between ADY and control were observed for the aforementioned variables. Fecal starch contents were not different among treatments, but the relative abundance of Bacteroidetes, as well as Prevotella at genera level, tended (P < 0.06) to be positively correlated to fecal starch content. We conclude that supplementing ruminally protected or non-protected ADY or ANT had no effect on diversity and richness of fecal bacteria of finishing beef cattle, whereas feeding protected ADY or ANT to finishing beef steers altered the dominant fecal bacteria at phylum and genus levels. Therefore, supplementation of ruminally protected ADY may potentially improve intestinal health by stimulating the relative abundance of Prevotella.

The objective of this study was to determine the effects of live yeast (LY) or yeast derivatives (YD) on gas production (GP), dry matter (DM) disappearance (DMD), fermentation characteristics, and microbial profiles in batch culture. The study was a completely randomized design with a factorial arrangement: 2 media pH × 5 yeasts × 4 dosages. An additional treatment of monensin (Mon) was added as a positive control for each pH level. Media pH was low (5.8) and high (6.5); the yeasts were three LY (LY1-3) and two YD (YD4-5); and doses were 0, 4 × 106, 8 × 106, and 1.6 × 107 cfu mL−1 for LY and 0, 15, 30, and 60 mg bottle−1 for YD. Substrate consisted of 10% silage and 90% concentrate (DM basis) and samples were incubated for 24 h. Media pH of 6.5 vs. 5.8, increased (P 3-N concentration and copy numbers of Ruminococcus albus, Ruminococcus flavefaciens, and Selenomonas ruminantium. Increasing dose of LY2 linearly (P

The objective of this study was to screening peptides for the effects on in vitro rumen dry matter (DM) digestibility (DMD) of feeds in batch culture. Three brewers spent grain (BSG) samples from different batches were obtained from a local brewery. Peptides were developed with BSG protein varying protease (alcalase, everlase, flavourzyme) and protease dosages (protease:BSG protein; 1:100, 5:100, 10:100, 15:100) under optimum pH and temperature conditions. In total, 36 peptides were produced and screened. A series of batch cultures were conducted and substrates were barley silage and barley grain. The experiment was a complete randomized design with a factorial arrangement; 3 proteases × 4 protease doses + 4 doses of each peptide (0, 0.5, 1.0, 1.5% of substrate DM) with 3 replications of each treatment combination. Rumen inoculum was from three rumen fistulated beef heifers fed a diet consisting of 10% silage and 90% concentrate (DM basis). The incubation was conducted at 39°C for 24 h. Interactions among protease, protease dose and peptide dose were not significant. For barley grain, DMD differed (P < 0.01) among proteases (85.2, 72.3, 65.2%, respectively, for alcalase, flavourzise, everlase). Increasing peptide doses from 0, 0.5, 1.0 to 1.5% linearly (P < 0.01) decreased the DMD from 88 to 78% (alcalase), 69 to 59% (everlase) and 78 to 67% (flavourzyme); whereas protease dose did not affect the DMD. With barley silage, the DMD was higher (P < 0.05) with flavourzyme (65.3%) than alcalase (59.2%) or everlase (61.2%); in contrast, the DMD was affected neither by protease dose nor by the peptide dose, except that increasing supplementation of peptide derived from everlase linearly (P < 0.05) decreased the DMD (65.1 to 58.9%). These results indicated that the peptides derived from BSG decreased in vitro rumen feed digestibility, which varied with proteases, peptide dose or feeds.

The objective of this study was to evaluate the effects of supplementing ruminally protected and non-protected active dried yeast (ADY; AB Vista, UK) on fecal bacterial diversity of finishing beef steers. Seventy-five Angus steers (initial BW 448 kg) were randomly assigned to one of five treatments: control, antibiotics (ANT, 330 mg monensin + 110 mg tylosin/d), ADY (1.5 g/d), encapsulated ADY (EDY; 3 g/d), and mixture of ADY and EDY (MDY). The ADY (1.7×1010 cfu/g) was encapsulated with equal amount of ADY and capsule material. Steers were fed a diet containing 10% barley silage and 90% barley concentrate (DM basis), ANT, ADY, EDY and MDY were top-dressed at feeding. Fecal samples were rectally collected from 10 steers of each treatment on d 56 to determine fecal bacterial diversity using high throughput MiSeq sequencing. Alpha diversity indices were not different among treatments. Principal coordinate analysis revealed that samples were not clustered by treatments. Bacteroidetes and Firmicutes were dominant phyla in the fecal bacterial community for all treatments, with a tendency (P < 0.10) of ANT, EDY and MDY to have greater relative abundance of Bacteroidetes (averaged 51.3 vs 46.8%) but lesser Firmicutes (averaged 39.5 vs 47.9%) than control steers. About 50 to 61% of sequences remained unclassified and identified 32 genus, with Prevotella ranging from 15.8 to 25.5% as the dominant genus in all treatments. Notably, steers with ANT, EDY, MDY vs. control had greater (P < 0.05) relative abundance of Prevotella (averaged 23.5 vs 16.8%) but lesser (P < 0.03) Oscillospira (averaged 1.7 vs 2.8%). No differences between ADY and control were observed for aforementioned variables. The results indicate that supplementing ruminally protected or non-protected ADY have limited effect on diversity of fecal bacteria, whereas feeding protected ADY and ANT to finishing beef steers altered dominant fecal bacteria at phylum and genus level.

The objectives of this study were to assess the effects of Saccharomyces cerevisiae fermentation products (SCFP; NaturSafe® and Original XPC™, Diamond V) on growth performance and antimicrobial resistance in beef steers. Ninety Angus steers (initial BW=533±9.8 kg) were assigned to a randomized complete design with 6 treatments: 1) control (10% barley silage and 90% barley concentrate, DM basis), 2–4) control diet with 12, 15 and 18 g/d NaturSafe, 5) control diet with 8 g/d encapsulated XPC (eXPC), and 6) control diet with antibiotics (ANT; 330 mg/d monensin and 110 mg/d tylosin). Data were analyzed using the MIXED procedure of SAS with the fixed effect of treatment and random effect of steers. Though the final BW (715 kg) and DMI (12.0 kg/d) were not affected by treatments, average daily gain tended (P < 0.10) to be greater in steers supplemented with eXPC compared with control (1.80 vs. 1.62 kg/d) with a trend (P < 0.09) for a linear increase in gain: feed with increasing NaturSafe. The proportion of total abscessed liver did not differ among treatments (58.9%), but the proportion of severely abscessed liver tended (P < 0.10) to be lower in cattle supplemented with 15 and 18 g NaturSafe/d, eXPC and antibiotics (20.0, 20.0, 20.0 and 6.7 vs. 53.3%). The percentage of erythromycin resistant and erythromycin + tetracycline resistant Enterococci increased (P < 0.05) in steers receiving antibiotics compared with control and SCFP group (34.57 vs. 4.28 and 6.88%), while no difference was observed between control and SCFP groups. These results indicate that NaturSafe and eXPC were beneficial in improving the growth performance by increasing average daily gain and feed efficiency. Both NaturSafe and eXPC could potentially act as alternatives to growth promoting antibiotics.

The study objective was to investigate the effects of site of delivering Saccharomyces cerevisiae fermentation product (SCFP) on ruminal pH and fermentation characteristics, and the site and extent of feed digestion in the digestive tract of beef heifers fed high-grain diets. Examining the ruminal and postruminal effects of SCFP is important for understanding the potential use of SCFP as an alternative for current industry-standard antibiotics used in beef cattle rations. Five beef heifers (initial BW = 561 ± 11.7 kg) equipped with ruminal and duodenal cannulas were used in a 5 × 5 Latin square design with 28-d periods, including 21 d for adaption and 7 d for data collection. Five treatments were as follows: 1) control diet that contained 10% barley silage and 90% barley concentrate mix (DM basis); 2) control diet supplemented with antibiotics (ANT; 330-mg monensin/d and 110-mg tylosin/d per head); 3) ruminal (top dress) delivery of SCFP (rSCFP; NaturSafe, Diamond V, 18-g SCFP/d); 4) duodenal delivery of SCFP (dSCFP; 18-g SCFP/d, via duodenal cannula); and 5) a combination of rSCFP and dSCFP (rdSCFP; 18-g rSCFP and 18-g dSCFP). Intake of DM tended (P 0.19), whereas the amount of truly fermented OM was greater (P < 0.03) with rdSCFP than the other treatments. Ruminal OM digestibility was highest with rSCFP and rdSCFP, intermediate with dSCFP and ANT, and lowest with control (P < 0.03). Intestinal digestibility was similar among treatments. As a result, total tract digestibility of OM (P < 0.07) and NDF (P < 0.01) was greater with rSCFP and rdSCFP than control and ANT. Fecal IgA concentration was highest with ANT, intermediate with dSCFP and rdSCFP, and lowest with control and rSCFP (P < 0.03). These results demonstrate that feeding SCFP improved stability of ruminal pH and digestibility of OM and NDF. Delivery of SCFP to the duodenum appeared to have little effect on nutrient digestibility but improved intestinal immune response. Feeding SCFP performed better or at least equal to antibiotics currently used in beef cattle rations and could be a natural alternative for beef cattle production.

Red osier dogwood (ROD) is a native shrub plant rich in phenolic compounds with antimicrobial properties. The objective of this study was to evaluate the effects of substituting barley silage with either raw ROD or ROD extract (RODE) in high-grain (HG) diet under a low media pH (5.8) on gas production (GP), dry matter (DM) disappearance (DMD) and fermentation characteristics in batch cultures. The study was a completely randomized design with 4 treatments: 1) control diet (10% barley silage and 90% barley concentrate, DM basis), control diet supplemented with 2) monensin (30 mg/kg diet DM; positive control), 3) substitution of 3% ROD or 4) 3% RODE for an equal portion of silage. Inoculum was obtained from 2 ruminally fistulated beef heifers offered the HG diet. Substrate ground (1 mm) was incubated for 24 h and the experiment repeated twice. The GP did not differ among treatments (147 ml/g DM), but the DMD differed (P < 0.02) at highest for control (69.4%), lowest for ROD (58.4%) and intermediate for other treatments (64.1%). Total volatile fatty acid (VFA) concentration (mM) tended (P< 0.08) to be lower with ROD (80.5) and monensin (80.1) than control (83.9). Acetate proportion was greater (P = 0.02) with ROD (46.2%) and RODE (46.9%) than control (42.4%) and monensin (42.3%). However, the propionate proportion was greater (P = 0.05) with monensin (32.1%) than other treatments (averaged 30.1%). Consequently, acetate to propionate ratio (A:P) of ROD (1.52) and RODE (1.56) was higher than monensin (1.32; P < 0.01) and control (1.44; P < 0.08). Differences in variables measured between ROD and RODE were minimal. These results indicated that the decreased DMD along with increased A:P with addition of ROD or RODE suggests that both ROD and RODE may be beneficial to HG fed cattle for reducing risk of rumen acidosis without negatively impacting fibre digestion.

Fatty acid (FA) composition in beef is related to beef quality and human health. It was recently reported that feeding active dried yeast (ADY) in finishing bull altered some FA of longissimus muscle. The objective was to evaluate the effects of adding ruminally protected versus non-protected ADY on FA profiles of the pars costalis diaphragmatis (PCD) muscle of beef cattle. Seventy-five Angus steers (initial BW 448 kg) were assigned to a randomized complete block design with five treatments: control (no additives), antibiotics (ANT, 330 mg monensin + 110 mg tylosin/d), ADY (1.5 g/d), encapsulated ADY (EDY, 3 g/d) and combination of ADY and EDY (MDY). The encapsulated ADY consisted of 1.5 g ADY and 2 g capsule. Antibiotics, ADY and EDY were top-dressed to a diet containing 10% barley silage and 90% barley concentrate (DM basis). The PCD samples were collected from cattle at slaughter. Intakes (g/d) of total FA (144), saturated FA (SFA; 41), monounsaturated FA (MUFA, 16) and polyunsaturated FA (PUFA, 87) were not different among treatments. Proportion of SFA (49.0%) and MUFA (48.2%) in PCD did not differ among treatments, whereas the proportion of PUFA was greater (P < 0.05) with EDY (3.0%) and MDY (3.0%) than control (2.4%). The proportion of n-3 FA also tended (P < 0.06) to be greater with EDY (0.49%) and MDY (0.50%) than control (0.41%) and ADY (0.41%). Steers fed EDY and MDY enhanced (P < 0.05) the proportion of linoleic acid (LA n-6) and decosapentaenoic acid (DPA n-3) compared with control. These results indicated that feeding EDY and MDY increased amounts of PUFA, FA n-3, LA n-6 and DPA n-3. Inclusion of encapsulated yeasts to diet might increase the amount of bioactive yeasts reached intestines and result in better utilization of PUFA from the digesta and increase the accumulation in the intramuscular fat.

BACKGROUND: Yeast products showed beneficial effects with respect to stabilizing ruminal pH, stimulating ruminal fermentation and improving production efficiency. Batch cultures were conducted to evaluate the effects of yeast products on gas production (GP), dry matter disappearance (DMD) and fermentation characteristics of high‐forage substrate. The study was a two media pH (5.8 and 6.5) × five yeasts (three live yeasts, LY: LY1, LY2, LY3; two yeast derivatives, YD: YD4, YD5) × four dosages factorial arrangement, with monensin (Mon) assigned as a positive control. RESULTS: Greater (P

Background This study was conducted to evaluate the feed nutritional value of brewers’ spent grain (BSG) residue resulting from protease aided protein removal. The nutritional value was measured as nutrient content, gas production, nutrient digestibility and fermentation characteristics in batch culture. Results Protein extraction process decreased content of crude protein but concentrated the neutral detergent fibre (NDF) and ferulic acid in BSG residue. The changes in the chemical composition of BSG residue varied with enzyme and enzyme dosage. Digestibility of dry matter (DMD) and NDF of residue differed among proteases. Increasing alcalase dosage linearly decreased DMD, whereas, the DMD linearly increased as everlase or flavourzyme dosage increased. Compared with BSG, the DMD, gas production and fermentation acid concentration of BSG residues were lower, whereas NDF digestibility was higher. Conclusions The substantially increased NDF content and improved in vitro NDF digestibility due to protease hydrolysis suggest that BSG residue can be potentially exploited as a viable fibre source for ruminant feeding.

Bioavailability of calcium in food is not high. Calcium ions can react with the organic acids such as oxalic acid and phytic acid in the food to form insoluble salt. Calcium phosphorylated inulin (CaPInu) was developed as a new potential functional food. Inulin was chemically modified by importing charged group using esterification with phosphate mixture in order to chelate calcium. Two equivalence points of the introduced phosphate groups were estimated to be around 3.85 and 8.76 by potentiometric titration. The structural characterization indicated that C6-OH in the chemical structure of phosphorylated inulin was located in the outside of the sugar ring and its steric hindrance was relatively small and esterification was performed with phosphate easily. CaPInu could stimulate the growth of Bifidobacteria and decrase pH in vitro fermentation. Low pH in colon is benefit to the dissolution of calcium. Mice fed CaPInu diet had a higher serum calcium and femur weight compared with the control diet.

The objective was to investigate the effects of processing index (PI, weight after processing/weight before processing × 100) of barley grain and dietary undegradable fiber (uNDF, 240 h of incubation in rumen) concentration on chewing behavior (3 days, video recording) and feed sorting of finishing beef cattle. Six ruminally cannulated beef heifers (BW=715 kg) were used in a 6 × 6 Latin square design with 3 PI (65, 75 and 85%; fine, medium, coarse, respectively) × 2 uNDF concentrations (low and high; 4.6 vs. 5.6% of DM) factorial arrangement. Heifers were fed ad libitum a TMR consisting of 10% barley silage (low uNDF) or 5% silage and 5% chopped straw (high uNDF), 87% dry-rolled barley grain, and 3% vitamin and mineral supplement. An interaction of PI with uNDF occurred (P < 0.01) for DM intake, ruminating and total chewing time. Intake of DM (kg/d) did not differ (12.1) between low and high uNDF diets with 65 or 75% PI, whereas it was greater (P < 0.05) for high (12.7) than low (12.1) uNDF diets with 85% PI. Eating time (min/d) was not affected by PI but eating time (106 vs. 95 min/d; P = 0.03) and eating index (9.3 vs. 8.0 min/kg DM; P = 0.02) were greater with high than low uNDF diets. Ruminating (305 vs. 258 min/d) and total chewing (406 vs. 357 min/d) times were greater (P < 0.05) with high than low uNDF at 65% PI, with no effect of uNDF at 75 and 85% PI. Moreover, no interaction between PI and uNDF and no effect of PI on sorting index was observed. Heifers fed high vs. low uNDF diets sorted (P < 0.01) against long particles (>19 mm). These results suggest that when cattle are fed finely processed barley, increasing uNDF concentration of the diet may promote chewing and benefit rumen health.

The objective of this study was to investigate the effects of barley type (two-row versus six-row) and processing method (grinding, dry-rolling and temper-rolling) on processing quality, dry matter (DM) disappearance (DMD), and fermentation characteristics in batch culture. The study was a completely randomized design with 2 barley types × 3 processing methods in a factorial arrangement. Thirty barley cultivars/lines were selected from a set of 85 cultivars/lines that were previously screened for in vitro DMD. The mean DMD values (g/kg) were 328 (low), 520 (medium), and 688 (high) after 48 of incubation. Ten representative samples of each DMD group (low, medium and high) of two- and six-row barley were selected. Barley samples were ground (1-mm screen), and dry- or temper-rolled to a processing index (PI) of 0.80. Particle size distribution (PSD) of rolled barley across 4.00-, 3.35-, 2.36-, 1.18-, 0.85-mm sieves, gas production (GP) kinetics, DMD and fermentation traits at 6, 24 and 48 h of incubation were measured. Two-row had higher kernel weight, test weight, plumpness, starch and ether extract content, and lower fibre content than six-row barley (P

The objective of this study was to evaluate the effects of supplementing the diet of finishing beef steers with active dried yeast (ADY) in ruminally protected and nonprotected forms on growth performance, carcass traits, and immune response. Seventy-five individually-fed Angus steers (initial body weight (BW) ± SD, 448 ± 8.4 kg) were assigned to a randomized complete design with 5 treatments: 1) control (no monensin, tylosin, or ADY), 2) antibiotics (ANT, 330 mg monensin + 110 mg tylosin·steer(−1)d(−1)), 3) ADY (1.5 g·steer(−1)d(−1)), 4) encapsulated ADY (EDY; 3 g·steer(−1)d(−1)), and 5) a mixture of ADY and EDY (MDY; 1.5 g ADY + 3 g EDY·steer(−1)d(−1)). Active dried yeast with 1.7 × 10(10) cfu/g was encapsulated in equal amounts of ADY and capsule materials (stearic acid and palm oil). Steers were fed a total mixed ration containing 10% barley silage and 90% barley-based concentrate mix (dry matter [DM] basis). The ANT, ADY, and EDY were top-dressed daily to the diet at feeding. Intake of DM, final BW, averaged daily gain (ADG), and gain-to-feed ratio (G:F) were unaffected by ADY or EDY. Carcass traits including hot carcass weight (HCW), dressing percentage, marbling score and quality grade did not differ among treatments, although fewer severely abscessed livers were observed (P < 0.05) with ADY and MDY compared with the other treatments. Plasma urea N tended (P < 0.10) to be greater in steers fed ANT, ADY, or EDY on day 56 and 112, while glucose remained stable in all treatments except greater (P < 0.02) plasma glucose occurred in steers fed MDY on day 112. Serum nonestrified fatty acid (NEFA) was unaffected by ADY or EDY, but it was greater (P < 0.03) in steers fed ANT compared with control. Plasma haptoglobin (Hp) and serum amyloid A (SAA) were affected by yeast supplementation on day 112, with greater (P < 0. 01) Hp in steers fed ADY, EDY, or MDY and lesser (P < 0.01) SAA in steers fed EDY and MDY than control. Lipopolysaccharide binding protein concentrations were greater (P < 0.01) in steers fed EDY and MDY on day 56. Supplementing with ADY (protected or nonprotected) or ANT had no effect on fecal IgA contents on day 56 and 112. Steers fed yeast (EDY or MDY) tended (P < 0.10) to have fewer fecal Escherichia coli counts than the control and ANT on day 56 and 112. These results indicate that feeding ADY to feedlot cattle may exhibit antipathogenic activity that conferred health and food safety beneficial effects including reduced liver abscess and potentially pathogen excretion, thus yeast may be an alternative to in-feed antibiotics in natural beef cattle production systems.

The purpose of this study was to evaluate the effect of a phytogenic feed additive (Digestarom® (DA), Biomin, Getzersdorf, Austria) on growth performance, feed intake, carcass traits, and liver abscesses of finishing beef steers. One hundred and twenty Angus × Charolais crossbred steers (initial BW 488 ± 26.5 kg) were used in a 110-d feeding experiment. Steers were blocked by weight and randomly assigned to 12 pens with 10 steers per pen. Each pen was allocated to 1 of 3 diets. Each diet contained 86.5% barley, 10.0% barley silage and 3.5% vitamin and mineral supplement on a dry matter basis. Digestarom® replaced barley grain in the vitamin and mineral supplement at 1.41 and 2.82 g/kg, to achieve average daily intakes of DA of 0 (Control), 0.5 (LowDA) and 1.0 g (HighDA) per steer. Diets were prepared once daily and offered ad libitum intake. Two pens per treatment were equipped to record individual feed intake ehavior. Steers were weighed every 28 d and carcass traits and liver scores were recorded at slaughter. Dry matter intake (average 9.34 kg/d) and final BW (average 669 kg) did not differ among treatments. Average daily gain (ADG) tended (P < 0.09) to increase in response to DA supplementation (control, 1.82; LowDA, 1.87; and HighDA, 1.95 kg/d), but gain:feed ratio was not affected. Supplementation of DA affected rib-eye area quadratically (P < 0.05) with the largest area observed for LowDA. Total abscessed livers were not affected, whereas proportion of severe liver abscesses was numerically lower (P < 0.15) with DA (31 and 43% for LowDA and HighDA, respectively) compared to the control (50%). The positive effect of DA on ADG and percentage of severely abscessed livers should be validated in larger scale feedlot studies.

The objectives were to investigate the effect of supplementing brewers’ spent grain (BSG) protein hydrolysates on rumen fermentation, nutrient digestibility, gas production and microbial protein synthesis in Rusitec. The experiment was a completely randomized design with four treatments assigned to sixteen fermenters in two Rusitec apparatuses. Protein hydrolysates from BSG were prepared using two proteases (Alclase and Flavourzyme) at 1% protease of BSG protein under optimum pH and temperature conditions. The treatments were control diet consisting of 10% barley silage and 90% barley concentrate (DM basis), control diet supplemented with alcalase hydrolysates (AlcH) or flavourzyme hydrolysates (FlaH) at 10 g/kg of diet DM, or antibiotics (Ant; 33 mg monensin + 11 mg tylosin/kg diet DM). The study consisted of 8 d for adaptation and 7 d for sampling. It was highest (P < 0.01) with control and AlcH, intermediate with FlaH and lowest with Ant for digestibility of DM (76.5, 76.1, 75.3, 72.7%), CP (75.1, 75.4, 73.4, 69.7%) and starch (90.7, 90.8, 89.5, 87.8%). Digestibility of NDF did not differ among control, AlcH and FlaH (average 39.3%), but higher (P < 0.01) than Ant (31.8%). Production of NH3-N (mmol/d) was greater (P < 0.01) in the order of AlcH and FlaH (average 4.1) > control (3.7) > Ant (2.6). The VFA production (average 54.3 mmol/d) and acetate/propionate ratio (average 0.79) were not different among control, AlcH and FlaH, but greater (P < 0.01) than Ant (48.9 mmol/d, and 0.69). Total gas production were not affected by treatments, but CH4 production (mg/g digested DM) was lower (P < 0.01) for FlaH (3.5) and Ant (2.2) than control (3.8). Microbial protein production (mg/d) was lesser (P < 0.05) for FlaH (476) and Ant (459) than control (502). These results indicate that adding FlaH in high-grain diet effectively reduced rumen CH4 production and CP degradability without affecting fibre digestion.

This study used a high-throughput in vitro microassay, in vitro batch culture, and the Rumen Simulation Technique (RUSITEC) to screen recombinant fibrolytic enzymes for their ability to increase the ruminal fiber degradability of barley straw. Eleven different recombinant enzymes in combination with a crude mixture of rumen enzymes (50% recombinant enzyme:50% crude mixture of rumen enzymes) were compared with the crude mixture of rumen enzymes alone. In the microassay, all treatments were applied at 15 mg of protein load per gram barley straw glucan. Based on the microassay results, 1 recombinant endoglucanase [EGL7A, from the glycoside hydrolase (GH) family 7], 2 recombinant xylanases (XYL10A and XYL10C, from GH10), and a recombinant enzyme mixture were selected and compared with a crude mixture of fibrolytic enzymes from Aspergillus aculeatus for their ability to hydrolyze barley straw. For batch culture, enzymes were applied to barley straw at 2 dosages (100 and 500 µg of protein/g of substrate DM). All enzymes increased (P < 0.05) DM disappearance and total VFA production, but the mixture of recombinant enzymes was not superior to the use of a single recombinant enzyme. Based on positive results (P < 0.05) for total DM disappearance and VFA production in batch culture, 3 enzymes (EGL7A, XYL10A, and XYL10C) were selected and applied to barley straw at 500 µg of protein per gram for further assessment in RUSITECs fed a concentrate:barley straw diet (300:700 g/kg DM). In RUSITECs, the recombinant enzyme XYL10A increased (P < 0.05) barley straw DM, NDF, and ADF disappearance, whereas EGL7A and XYL10C had no effect. The enzymes selected based on the high-throughput in vitro microassay consistently increased barley straw degradation in ruminal batch culture, but not in the semicontinuous culture RUSITEC system.

The objectives of this study were to evaluate the effects of pretreating dairy cow rations with a fibrolytic enzyme derived from Trichoderma reesei (FETR; mixture of xylanase and cellulase; AB Vista, Wiltshire, UK) on lactation performance, digestibility, and feeding behavior in response to feeding a barley silage-based diet. Before starting the dairy trial, in vitro incubations were conducted to determine whether the addition of FETR would have an effect on these animal performance characteristics when applied to a barley silage-based diet for dairy cows. The dairy trial was performed using 8 Holstein dairy cows. The cows were blocked by parity and assigned randomly to 1 of 4 treatments: 0, 0.5, 0.75, and 1 mL of FETR/kg of dry matter (DM) diet in a replicated Latin square design. The pretreatment was applied to the complete diet during the mixing process. The experimental period continued for 22 d, with each experimental period consisting of a 16-d adaptation period and a 6-d sampling period. The daily feed intake of each individual cow was monitored using Insentec feed bins (RIC system, Insentec, Marknesse, the Netherlands). Feeding behavior characteristics were measured during the entire sampling period using the feed bin attendance data. Milk samples were collected in the last 3 d of each experimental period. The addition of FETR linearly increased the in vitro DM digestibility and tended to improve the in vitro digestibility of barley silage. There was a cubic effect of the enzyme levels on the total-tract DM and neutral detergent fiber digestibility. Maximal digestibility was reached at 0.75 mL of FETR/kg of TMR. The milk fat yield, fat-corrected milk, and energy-corrected milk quadratically responded to the incremental levels of FETR. The milk protein percentage linearly improved in response to FETR. Increasing FETR levels resulted in a quadratic effect on feed efficiency. There was no effect of FETR level on feeding behavior. In conclusion, pretreating dairy cow barley silage-based diet with 0.75 mL of FETR/kg of TMR increased the milk production efficiency of dairy cows fed diet containing 34% barley silage (DM basis). The positive effect of adding FETR could benefit the dairy industry in western Canada, where barley silage-based diets are common.

The objectives of this study were to assess the magnitude of differences among barley silages with different in vitro neutral detergent fiber digestibility (ivNDFD) in comparison with corn silage i...

Low digestibility of crop residues limits their use as animal feeds. The study examined the potential of Ammonia Fibre Expansion (AFEX) technology and dietary supplementation of a preselected recombinant xylanase to improve the in situ degradability of four crop residues for ruminants. AFEX pretreatment uses anhydrous ammonia, moisture, moderate temperature, and a short period of high pressure and results in partial lignin solubilization and hemicellulose hydrolysis, and increased surface area of substrate for microbial attachment. In situ neutral detergent fibre degradabilities of untreated (control) and AFEX pretreated crop residues (barley straw, corn stover, rice straw, and wheat straw) were determined in 8 heifers using a 2-period cross-over design with two dietary treatments (without and with XYL10C; 1,4-β-xylanase; recombinant enzyme from glycoside hydrolase family 10 produced by Aspergillus niger). The enzyme was diluted in water and applied to the barley straw (6.6 × 104 IU enzyme/kg straw dry matter) component of the basal diet (30 g/100 g diet dry matter) and to the control and AFEX crop residues incubated in situ. There were no interactions between enzyme and crop residues for A, B, or A + B fractions, indicating no enzyme × substrate specificity. Averaged across crop residues, enzyme slightly decreased the A fraction (P

Corn and wheat grains are two starch sources with considerably different ruminal digestion rates, which may lead to differing lipopolysaccharide (LPS) release in both rumen and hindgut affecting animal production. The objectives of this study were to (1) investigate the effects of different ruminal and faecal LPS concentrations induced by starch source (corn vs wheat) and starch concentrations (low vs high) on DMI, ruminal pH, ruminal fermentation patterns, milk production, and inflammatory responses; and (2) evaluate the possible translocation site of LPS in dairy goats. Eight lactating dairy goats with ruminal cannulas were used in a replicated 4 × 4 Latin square design with 2 × 2 factorial arrangement of treatments. Each experimental period consisted of 24 days long including 21 days for adaption and 3 days for data and sample collection. The four treatment diets were: corn and wheat grain combined with low (LS) and high grain starch (HS). Goats were fed equal amounts of a total mixed ration twice daily at 0700 hours and 1900 hours. Replacing corn with wheat in goat diet led to longer (P < 0.02) duration of ruminal pH

Wheat dried distillers grains with solubles (DDGS) is widely used as a partial replacement for forages or concentrates in ruminant diets. We hypothesised that using exogenous enzymes (ENZ) would increase neutral detergent fibre (NDF) degradability of DDGS. The aims of the study were to (i) evaluate the effects of ENZ and their doses on in vitro gas production (GP) and degradability of wheat DDGS; and (ii) explore possible relationships between the major added enzymic activities and degradation, especially NDF degradation. Three commercially produced ENZ products that provided a range of xylanase, endoglucanase, exoglucanase and protease activities were used. Enzyme activities were assayed under normal rumen conditions with pH 6.0 and temperature 39°C. All three ENZ had a xylanase:endoglucanase ratio of 5:1 to 4:1, but ENZ3 had lower activity per millilitre. ENZ2 had relatively higher exoglucanase activity compared with the other products, with a ratio of xylanase:exoglucanase of 4:1 for ENZ2 compared with 23:1 for ENZ1 and 9:1 for ENZ3. Variable effects of the three ENZ products were observed on GP variables. Degradabilities of dry matter (DM), NDF, acid detergent fibre (ADF) and crude protein (CP) linearly (p

This study evaluated the composition, digestibility [dry matter digestibility (DMD)], CH4 abatement potential, and fatty acid biohydrogenation of six species of microalgae. Lipid content ranged from 115 g kg−1 dry matter (DM) (Scenedesmus sp. AMDD) to 361 g kg−1 DM (Tetracystis sp.), while Scenedesmus sp. AMDD had the highest carbohydrate (364 g kg−1 DM) and fibre content (277 g kg−1 DM). Gas production was highest (P −1 for Scenedesmus sp. AMDD to 797 g kg−1 for Nannochloris bacillaris. Total CH4 differed (P −1 DM for Tetracystis sp. to 4.07 mL g−1 DM for M. reisseri. Nannochloropsis granulata (marine) had higher myristic, palmitoleic, and eicosapentaenoic acid levels than freshwater microalgae. Levels of α-linolenic acid were higher in Scenedesmus sp. AMDD than all other microalgae. CH4 production negatively correlated (P 4 reductions with Scenedesmus sp. AMDD were comparable to Tetracystis sp. and N. bacillaris. Reductions in CH4 with Tetracystis sp. and N. bacillaris occurred without a decline in DMD, suggesting that overall microbial activity was not inhibited.

BACKGROUND Cinnamaldehyde (CIN) is the main active component of cinnamon (Cinnamomum cassia) oil and has been tested as alternative feed additive in cattle production. Little information was available on the effect of dietary CIN in comparison to monensin (MO) on beef fatty acid (FA) profile. This study analyzed FA profiles of liver, subcutaneous fat and pars costalis diaphragmatis (PCD) muscle obtained from steers (n = 70) finished on diets: control, a barley grain–silage feedlot diet; 330 mg/head.day MO; and 400, 800 or 1600 mg/head.day CIN treatments. RESULTS Inclusion of MO or CIN did not affect total saturated, unsaturated, polyunsaturated FA and individual FA in the various tissues with exceptions that proportion of palmitic acid in PCD muscle was increased by 800 mg/steer.day CIN (P < 0.05). There were positive correlations (P < 0.05) on oleic, linoleic, conjugated linoleic acid (CLA)-c9,t11 and 18:1-t10 between the subcutaneous fat and PCD muscle, and on α-linolenic acid, CLA-c9,t11 and 18:1-t10 between PCD muscle and liver, whereas correlations on the FA between the subcutaneous fat and liver were not significant except for 18:1-t10 (P < 0.01). CONCLUSION The results indicate that the supplementation of CIN and MO to feedlot diet has limited effect on beef FA profiles. © 2014 Her Majesty the Queen in Right of Canada Journal of the Science of Food and Agriculture © 2014 Society of Chemical Industry

Twenty multiparous lactating Holstein cows in early lactation were used to investigate effects of exogenous fibrolytic enzyme supplementation on dry matter intake, milk production, and digestibility. Cows were blocked according to parity, expected calving date, and milk yield in the previous lactation, and then randomly assigned after calving to two treatments: control or enzyme. The enzyme mixture, which contained mainly xylanase and cellulase activities (Pro-Mote, Biovance Technol. Inc., Omaha, NE), was added to the concentrate to supply 1.3 g/kg of total mixed ration (dry matter basis). The total mixed rations contained 24% corn silage, 15% alfalfa hay, and 61% barley concentrate (dry matter basis) and were offered for ad libitum intake. Enzyme addition did not affect dry matter intake. However, total digestibility of nutrients, determined using Cr2O3, was dramatically increased by enzyme treatment (dry matter, 61.7 vs. 69.1%; neutral detergent fiber, 42.5 vs. 51.0%; acid detergent fiber, 31.7 vs. 41.9%; crude protein, 61.7 vs. 69.8%). Consequently, milk yield tended to increase (35.9 vs. 39.5 kg/d). Percentage of milk fat was lower, and percentages of milk protein tended to be lower for cows fed a diet supplemented with enzymes, such that component yields were similar for cows fed either diet. Energy deficiency was numerically lower for cows fed a diet supplemented with enzymes than for cows fed the control diet (-3.62 vs. -3.33 Mcal/d). Supplementing dairy cow diets with a fibrolytic enzyme mixture has the potential to enhance milk yield and nutrient digestibility of cows in early lactation without changing feed intake.

A study was conducted using lactating Holstein cows with ruminal and duodenal cannulas in a 4 x 4 Latin square design to investigate fibrolytic enzyme supplementation on site and extent of nutrient digestion. The four diets consisted of 45% concentrate, 10% barley silage, and 45% cubed alfalfa hay (dry matter basis) and differed in enzyme supplementation: 1) control cubes, 2) cubes treated with 1 g of enzyme mixture/kg of cubes, 3) cubes treated with 2 g of enzyme mixture/kg of cubes, and 4) both concentrate and cubes treated with 1 g of enzyme mixture/kg of dry matter. The enzyme supplement contained primarily cellulase and xylanase activities. Digestion of organic matter and neutral detergent fiber in the total tract was higher for cows fed the high dosage of enzyme than for cows fed the control cubes. Ruminal digestibility of crude protein was higher, but that of organic matter and neutral detergent fiber was only numerically higher, for cows fed the high dosage of enzyme compared with that of cows fed the control cubes. Higher ruminal digestibility associated with the high dosage of enzyme resulted in more microbial protein synthesis. Milk production increased for cows fed the high dosage of enzyme compared with cows fed the control cubes and effects of the addition of enzyme on milk composition were minimal. The results demonstrated the benefits of using a fibrolytic enzyme additive to enhance feed digestion and milk production by dairy cows. The response to enzyme supplementation was affected more by amount of enzyme than by whether the enzyme was added to forage or concentrate.

Six lactating, cannulated Holstein cows were used in a double 3 x 3 Latin square design to compare the effects of hull-less barley with barley and corn on ruminal fermentation, rate of passage, flow of nutrients to the duodenum, and milk production. Diets consisted of 60% concentrate, 30% barley silage, and 10% alfalfa hay (dry matter basis). Concentrates contained steam-rolled grains: hull-less barley, barley, or corn. Dry matter intake was unaffected by grain source, but starch intake tended to be greatest when hull-less barley or corn was fed. The barley diet was more degradable in the rumen than was the hull-less barley or corn diet, and, therefore, flow of microbial organic matter to the duodenum was greatest for cows fed the barley diet. Flow of microbial N to the duodenum was greater (50 g/d) for cows fed the barley diet than for cows fed the other diets, and the flow of ruminally undegradable N was greater (43 and 28 g/d) for cows fed the hull-less barley and corn diets, respectively, than for cows fed the barley diet. As a result, flow of nonammonia N to the duodenum was unaffected by grain source. Total tract apparent digestibility was highest for cows fed the barley and corn diets. Despite its low digestibility, cows fed the hull-less barley diet produced a similar amount of milk as did cows fed the barley and corn diets. Further studies are needed to evaluate the effects of processing hull-less barley on its utilization by dairy cows.

Corn seed is a major ingredient of animal feed worldwide. However, it contains phytate, a major phosphate storage form that is unavailable to monogastric animals like pigs and poultry. We report a transgenic corn with bioavailable phosphate, achieved by seed-specific overexpression of Aspergillus niger phytase, an enzyme catalyzing the release of phosphate from phytate. We obtained maximal phytase activity of 125 FTU/g kernels, 1000-fold above that of the wild type, with 1000 g of kernels containing up to 67 times the feed industry requirement. Enzymatic characterization of Zea mays recombinant phytase (ZmrPhy) showed it to be equivalent to yeast (Pichia pastoris) recombinant phytase (PprPhy), a commercially available phytase product. An animal feeding trial demonstrated that ZmrPhy had similar nutritional effects on broiler chickens to PprPhy in terms of reducing inorganic phosphorus addition to feed and phosphate excretion in animal manure. These results suggest that transgenic phytase corn can be used directly in the feed industry. Experiments were conducted to assess the food safety of the corn; the results demonstrated no difference versus regular corn. This is the first genetically modified corn officially issued with a biosafety certificate in China and has great potential in the animal feed industry.

This study was conducted to evaluate the effect of wheat dried distillers' grains with solubles (DDGS) and cinnamaldehyde (CIN) on in vitro fermentation and microbial profiles using the rumen simulation technique. The control substrate (10% barley silage, 85% barley grain and 5% supplement, on dry matter basis) and the wheat DDGS substrate (30% wheat DDGS replaced an equal portion of barley grain) were combined with 0 and 300 mg CIN/l of culture fluid. The inclusion of DDGS increased (p0.05) the concentration of volatile fatty acids (VFA) and the molar proportion of acetate and propionate. Dry matter disappearance (p = 0.03) and production of bacterial protein (p0.01) were greater, whereas the disappearances of crude protein (CP) and neutral detergent fibre were less (p0.01) for the DDGS than for the control substrate. With addition of CIN, concentration of total VFA decreased and fermentation pattern changed to greater acetate and less propionate proportions (p0.01). The CIN reduced (p0.01) methane production and CP degradability. The copy numbers of Fibrobacter, Prevotella and Archaea were not affected by DDGS but were reduced (p0.05) by CIN. The results indicate that replacing barley grain by DDGS increased nutrient fermentability and potentially increase protein flows to the intestine. Supplementation of high-grain substrates with CIN reduced methane production and potentially increased the true protein reaching the small intestine; however, overall reduction of feed fermentation may lower the feeding value of a high-grain diet.

Four lactating, cannulated Holstein cows were used in a 4 × 4 Latin square design to investigate the effects of grain source and fibrolytic enzyme supplementation on ruminal fermentation, nutrient digestion in the rumen and in the intestine, and milk production. A 2 × 2 factorial arrangement was used; two grains (barley and hull-less barley) were combined with and without enzyme. The enzyme supplement (Pro-Mote®; Biovance Technologies Inc., Omaha, NE) contained primarily cellulase and xylanase activities and was applied daily to the total mixed diet. Dry matter intake was not affected by diet, but starch intake was greatest when hull-less barley was fed. Starch from hull-less barley was more digestible in the rumen and in the total tract than was starch from barley, but opposite results occurred for fiber digestion, indicating that hull-less barley depressed fiber digestion. As a result, cows fed the hull-less barley diets tended to produce more milk with a higher milk lactose content than did cows fed the barley diets. Enzyme supplementation had minimal effects on ruminal digestion but increased nutrient digestibility in the total tract and the proportion of microbial N in nonammonia N. Consequently, cows fed diets supplemented with enzyme had a higher milk protein content and tended to produce more 4% fat-corrected milk than did control cows. These results indicate that the use of hull-less barley rather than barley increased the digestible energy intake of dairy cows, resulting in higher milk production. The use of a fibrolytic enzyme mixture enhanced feed digestibility and milk production.