Wheat distillers grains in feedlot cattle diets: feeding behavior, growth performance, carcass characteristics, and blood metabolites

Investigating the Effects of Distillers Grains on Heifer Feeding Behavior in the Finishing Phase

Simple Summary

Dried distillers grains (DDG), a corn by-product of the ethanol industry, are a common feedstuff in cattle diets. Distillers can be used in diets as an effective source of protein and can reduce risk of acidosis by reducing the highly fermentable carbohydrate of starch. However, the price and availability of distillers grains are variable based on droughts, energy prices, and other factors. When inclusion of distillers grains in diets becomes uneconomical or is not possible, diets may decrease in crude protein and increase in starch-altering rumen fermentation parameters and feeding behavior. The effect of distillers grains on cattle growth performance and carcass traits has been studied extensively, but little is known about how distillers inclusion affects feeding behavior. Therefore, the objective of this experiment was to determine the effect of low inclusion levels of DDG on feeding behavior in heifers consuming a high-moisture corn-based diet in the finishing phase. This study demonstrated that low inclusion levels of distillers grains has little effect on growth performance, but can alter feeding behavior and reduce variability in feeding behavior traits.

Abstract

The objective was to determine the effect of low inclusion levels of dried distillers grains (DDG) on feeding behavior in heifers consuming a high-moisture corn-based diet in the finishing phase. Simmental × Angus heifers (N = 90; 323 ± 50 kg) were fed for 180 d. Heifers were blocked by initial body weight (BW) into two groups, stratified by sire, and assigned to 15 pens with six heifers each. Pens were randomly assigned to one of three dietary treatments: 0% DDG inclusion (0DG), 7% DDG inclusion (7DG), or 14% DDG inclusion (14DG). Treatments did not affect (p > 0.59) BW, average daily gain, and gain:feed. Although there was a treatment × time effect (p = 0.05) for dry matter intake (DMI), with 0DG having greater DMI during the last 70 d, no differences in overall DMI were detected. Treatment affected (p < 0.01) bunk visit duration and head down duration, with 7DG and 14DG having less minutes per day. Bunk visit frequency (p = 0.02) was less variable for heifers fed 14DG and DMI tended (p = 0.08) to be less variable for both distillers treatments. While dietary inclusion of DDG has minimal effects on overall heifer performance, low levels of DDG inclusion can affect feeding behavior and intake variation.

Effects of brewers' spent grain protein hydrolysates on gas production, ruminal fermentation characteristics, microbial protein synthesis and microbial community in an artificial rumen fed a high grain diet

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 < 0.01) disappearances of dry matter (DM), organic matter (OM), CP and starch, without affecting fibre disappearances; while AlcH had no effect on nutrient disappearance. Neither AlcH nor FlaH affected gas production or VFA profiles, however they increased (P < 0.01) NH3-N and decreased (P < 0.01) H2 production. Supplementation of FlaH decreased (P < 0.01) the percentage of CH4 in total gas and dissolved-CH4 (dCH4) in dissolved gas. Addition of monensin reduced (P < 0.01) disappearance of nutrients, improved fermentation efficiency and reduced CH4 and H2 emissions. Total microbial nitrogen production was decreased (P < 0.05) but the proportion of feed particle associated (FPA) bacteria was increased with FlaH and monensin supplementation. Numbers of OTUs and Shannon diversity indices of FPA microbial community were unaffected by AlcH and FlaH; whereas both indices were reduced (P < 0.05) by monensin. Taxonomic analysis revealed no effect of AlcH and FlaH on the relative abundance (RA) of bacteria at phylum level, whereas monensin reduced (P < 0.05) the RA of Firmicutes and Bacteroidetes and enhanced Proteobacteria. Supplementation of FlaH enhanced (P < 0.05) the RA of genus Prevotella, reduced Selenomonas, Shuttleworthia, Bifidobacterium and Dialister as compared to control; monensin reduced (P < 0.05) RA of genus 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.

Effect of a pine enhanced biochar on growth performance, carcass quality, and feeding behavior of feedlot steers

The objective of this study was to evaluate the effect of enhanced biochar (EB) on growth performance, carcass quality, and feeding behavior of feedlot steers fed high-forage and high-grain diets. A total of 160 crossbred steers (initial 286 ± 26 kg body weight [BW]) were blocked by BW and randomly assigned to 16 pens (10 steers per pen), 8 of which were equipped with the GrowSafe system for monitoring feeding behavior. Treatments were EB included in the diet at 0% (control), 0.5%, 1.0%, or 2.0% (dry matter [DM] basis) with four pens per treatment. The backgrounding phase (84 d) was divided into four 21-d periods, and the finishing phase (112 d) was divided into four 28-d periods, with a 28-d transition period for dietary adaptation. Pen was the experimental unit for all parameters except for feeding behavior, where steer was considered the experimental unit. Treatment was included as a fixed effect, and period was considered a repeated measure. Total weight gain and overall average daily gain (ADG) tended to decrease (P = 0.06) with 2.0% EB. There was no effect (P ≥ 0.13) of EB on dry matter intake (DMI), gain-to-feed ratio (G:F), net energy for gain, ADG, or final BW for the backgrounding or finishing phases. There was a treatment × period effect (P < 0.05) of EB on DMI, ADG, and G:F for both backgrounding and finishing phases. Hot carcass weight, dressing %, back fat, rib-eye area, and meat yield were not affected (P ≥ 0.26) by EB. Lean meat yield was increased (P = 0.03) by 2.0% EB compared to all other treatments. Compared to the control, 2.0% EB increased (P = 0.02) the number of carcasses that achieved Canada 1 grade. More (P = 0.05) carcasses from control steers were graded as Canada 3 as compared to those fed 0.5% or 2.0% EB. Quality grade and incidences of liver abscesses were not affected (P ≥ 0.44) by EB. Enhanced biochar had no effect (P ≥ 0.11) on feeding behavior during backgrounding or finishing phases. In conclusion, EB did not result in changes in growth rate, feed efficiency, or feeding behavior in feedlot cattle, but 2.0% EB increased lean carcass yield grade.

Effects of an increased concentrate diet on rumen pH and the bacterial community in Japanese Black beef cattle at different fattening stages

This study evaluated the effects of increasing the proportion of concentrate in the diet on the rumen pH and bacterial community in Japanese Black beef cattle at different fattening stages. Six rumen-cannulated beef cattle were studied in the middle (Mid group, n=3, age 21–22 months) and late (Late group, n=3, age 31 months) fattening stages. The cattle were fed rice straw with control (CON period) or high-concentrate (HC period) diets for 14 consecutive days in each period. Rumen pH was measured continuously and the rumen fluids were collected on the last day of each period. The 24-hr mean and minimum rumen pH in the Mid group were significantly (P<0.05) lower during the HC period compared with the CON period, whereas those in the Late group were continuously low during both periods. In the Late group, the ruminal volatile fatty acid and lactic acid concentrations were significantly (P<0.05) higher during the HC period. During the HC period, the proportions of Prevotella and Caloramator were significantly (P<0.05) higher and lower, respectively, in the Mid group. From these findings, significant changes in the rumen pH and bacterial community induced by dietary changes were mainly observed in the Mid group. Therefore, the ruminal fermentative function in response to a higher concentrate diet might adapt differently in Japanese Black beef cattle at the two different fattening stages.

The combined effects of supplementing monensin and 3-nitrooxypropanol on methane emissions, growth rate, and feed conversion efficiency in beef cattle fed high-forage and high-grain diets

The study objective was to evaluate the combined effects of supplementing monensin (MON) and the methane (CH4) inhibitor 3-nitrooxypropanol (NOP) on enteric CH4 emissions, growth rate, and feed conversion efficiency of backgrounding and finishing beef cattle. Two hundred and forty crossbred steers were used in a 238-d feeding study and fed a backgrounding diet for the first 105 d (backgrounding phase), transition diets for 28 d, followed by a finishing diet for 105 d (finishing phase). Treatments were as follows: 1) control (no additive); 2) MON (monensin supplemented at 33 mg/kg DM; 3) NOP (3-nitrooxypropanol supplemented at 200 mg/kg DM for backgrounding or 125 mg/kg DM for finishing phase); and 4) MONOP (33 mg/kg DM MON supplemented with either 200 mg/kg DM or 125 mg/kg DM NOP). The experiment was a randomized complete block (weight: heavy and light) design with 2 (NOP) × 2 (MON) factorial arrangement of treatments using 24 pens (8 cattle/pen; 6 pens/treatment) at the main feedlot and 8 pens (6 cattle/pen; 2 pens/treatment) at the controlled environment building (CEB) feedlot. Five animals per treatment were moved to chambers for CH4 measurements during both phases. Data were analyzed using a Mixed procedure of SAS with pen as experimental unit (except CH4). Location (Main vs. CEB) had no significant effect and was thus omitted from the final model. Overall, there were few interactions between MON and NOP indicating that the effects of the 2 compounds were independent. When cattle were fed the backgrounding diet, pen DMI was decreased by 7%, whereas gain-to-feed ratio (G:F) was improved by 5% with NOP supplementation (P < 0.01). Similarly, MON improved G:F ratio by 4% (P < 0.01), but without affecting DMI. During the finishing phase, DMI tended (P = 0.06) to decrease by 5% with both MON (5%) and NOP (5%), whereas ADG tended (P = 0.08) to decrease by 3% with MON. Gain-to-feed ratio for finishing cattle was improved with NOP by 3% (P < 0.01); however, no effects were observed with MON. 3-Nitrooxypropanol decreased CH4 yield (g/kg DMI) by 42% and 37% with backgrounding and finishing diets (P ≤ 0.01), respectively, whereas MON did not lower CH4 yield. Overall, these results demonstrate efficacy of NOP in reducing enteric CH4 emissions and subsequently improving feed conversion efficiency in cattle fed high-forage and high-grain diets. Furthermore, effects of NOP did not depend on whether MON was included in the diet.

Effects of encapsulated nitrate on growth performance, carcass characteristics, nitrate residues in tissues, and enteric methane emissions in beef steers: Finishing phase

A finishing feedlot study was conducted with beef steers to determine effects of encapsulated nitrate (EN) on growth performance, carcass characteristics, methane production, and nitrate (NO) residues in tissues. The 132 crossbred steers were backgrounded in a feedlot for 91 d and transitioned for 28 days to the high-concentrate diets evaluated in the present study, maintaining the treatment and pen assignments designated at the start of the backgrounding period. The steers were initially assigned to 22 pens (6 animals per pen) in a randomized complete block design with BW (18 pens) and animals designated for methane measurement (4 pens) as blocking factors. Five animals in each pen designated for methane measurement (total of 20 animals) were monitored for methane emissions in respiratory chambers twice during the experiment. Pens received 3 dietary treatments (7 pens each): Control, a finishing diet supplemented with urea; 1.25% EN, control diet supplemented with 1.25% encapsulated NO in dietary DM that partially replaced urea; and 2.5% EN, control diet supplemented with 2.5% EN (DM basis) fully replacing urea. The final pen designated only for methane measurement received a fourth dietary treatment, 2.3% UEN, the control diet supplemented with unencapsulated NO (UEN) fully replacing urea. The cattle weighed 449 ± SD 32 kg at the start of the 150-d finishing period. The 2.5% EN diet decreased ( < 0.01) DMI compared with Control and 1.25% EN diets. Feeding EN tended to increase ( = 0.092) ADG compared with Control, and G:F was improved ( < 0.01) for EN compared with Control. No differences in methane production (g/d) and yield (g/kg DMI) were observed among treatments. Inclusion of EN in the diets increased ( ≤ 0.03) sorting in favor of large and medium particles and against small and fine particles. Plasma NO and NO concentrations were elevated ( < 0.01) with EN in a dose-response manner, but total blood methemoglobin levels for all treatments were low, below the detection limit. Feeding EN increased ( < 0.01) NO concentrations of samples from muscle, fat, liver, and kidney; NO concentrations of these tissues were similar between 1.25% EN and 2.3% UEN. In conclusion, inclusion of 2.5% EN in a finishing diet (DM basis; about 2% NO) did not cause NO toxicity or any health problems in the long term. In comparison with supplemental urea, feeding EN improved feed efficiency despite increases in sorting against dietary EN.

Effects of Leymus chinensis replacement with whole-crop wheat hay on blood parameters, fatty acid composition, and microbiomes of Holstein bulls

This study investigated the replacement of Leymus chinensis (LC) with whole-crop wheat hay (WCWH) in the diets of Holstein bulls in the fattening stage and examined the potential effects on blood parameters, fatty acids in rumen fluid and serum, and the rumen microbiomes. In this study, 12 Holstein bulls in the fattening period (body weight = 485.0 ± 40.8 kg) were assigned to 1 of 4 dietary treatments using a 4 × 4 Latin square design. Each experimental period consisted of a 17-d adaptation period and a 5-d collection period. The dietary treatments consisted of 4 proportions of WCWH (0, 33, 67, and 100%) as a substitute for LC (designated as WCWH0, WCWH33, WCWH67, and WCWH100, respectively). On d 18 and 22 of each experiment period, blood and rumen content samples were collected for analysis, respectively. Real-time quantitative PCR was used to analyze the rumen microbiomes. The results from this study revealed no differences in the saturated, monounsaturated, and polyunsaturated long-chain fatty acid proportions of rumen liquid among the treatments. It was observed in the present trial that rumen microbiotal flora were not significantly different in the bulls fed LC compared with the bulls fed WCWH. Additionally, blood sample analysis demonstrated that the concentration of urea nitrogen in the WCWH100 group was higher than that observed in the other groups. Meanwhile, no differences were detected for other serum parameters. There were no differences in the proportions of serum saturated, monounsaturated, and polyunsaturated long-chain fatty acids among the treatments. In conclusion, our data revealed that LC can be replaced with WCWH in the diet of Holstein bulls in the fattening stage with no negative effects on the blood indicators, fatty acids, and microbiomes.

Effects of replacing Leymus chinensis with whole-crop wheat hay on Holstein bull apparent digestibility, plasma parameters, rumen fermentation, and microbiota

Twelve Holstein bulls were used in a 4 × 4 Latin square design to investigate the effects of using whole-crop wheat hay (WCWH) as a substitute for Leymus chinensis (LC) on apparent digestibility, plasma parameters, ruminal fermentation, and microbial communities. Experimental treatments were four proportions of WCWH, 0, 33, 67, and 100%, as a substitute for LC (WCWH0, WCWH33, WCWH67, and WCWH100, respectively). The WCWH100 group showed a higher nutritional intake of crude protein (CP) and higher apparent digestibility of organic matter (OM), CP, and ether extract (EE) than the WCWH0 group (P < 0.05). Urea N, NH3-N, isobutyrate and isovalerate levels were higher (P < 0.05) in the WCWH100 group than in the WCWH0 group. 16S rRNA high-throughput sequencing analysis revealed similarities in the community composition, species diversity and relative abundance of dominant bacteria at the phylum and genus levels among the four groups. Collectively, our data indicated that WCWH can be used to replace LC in the diet of finishing dairy bulls without having a negative impact on apparent digestibility, plasma parameters, and ruminal bacteria composition. These results offer the first deep insight into the effects of replacing LC with WCWH on the performance parameters and rumen microbiota in Holstein bulls, and may aid in ruminant farming.

Effect of diastatic power and processing index on the feed value of barley grain for finishing feedlot cattle

The objective of this study was to assess the nutritional value of barley grain differing in diastatic power (DP; high vs. low; a malt trait) and processing index (PI; 75 vs. 85). One hundred sixty Angus × Hereford crossbred yearling steers (467 ± 38 kg; 144 intact and 16 rumen cannulated) were used in a complete randomized 2 × 2 factorial experiment. Steers were assigned to 16 pens, 8 of which were equipped with the GrowSafe system to measure individual feed intake. Cannulated steers (2 per pen) were randomly assigned to the 8 GrowSafe pens. Diets consisted of high- or low-DP barley grain (80.0% of diet DM) processed to an index of either 75 or 85% (PI-75 and PI-85, respectively). Ruminal pH in cannulated steers was measured over four 5-d periods using indwelling electrodes. Fecal samples were collected every 28 d from the rectum of each steer to assess digestibility using AIA as a marker. No differences ( > 0.10) in rumen pH were observed among cattle as measured by the indwelling pH meters. However, lower ( < 0.05) rumen pH was observed for steers fed low- as opposed to high-DP barley in rumen samples collected just prior to feeding and measured in the laboratory. Intake of DM and OM were not affected ( ≥ 0.24) by DP but were lower ( < 0.01) with more severe processing (PI-75 vs. PI-85). Low-DP barley tended to exhibit higher ( = 0.09) total tract DM digestibility than high-DP barley. Steers fed PI-75 barley also had higher ( = 0.06) G:F and NEg. Digestibility of DM, OM, CP, NDF, and starch was higher ( < 0.05) for PI-75 barley than for PI-85 barley. Low-DP barley increased ( < 0.05) carcass dressing percentage by 0.5% compared with high-DP barley, with a lower PI tending to increase ( = 0.06) rib eye area. Compared with steers fed high-DP diets, steers fed low-DP diets had more ( = 0.01) total (41.7 vs. 19.4%) and severe liver abscesses (22.2 vs. 9.7%). Results suggest that although low-DP barley increased liver abscesses, differences in DP did not alter digestion or growth performance but low-DP barley did improve dressing percentage. Barley with different DP responded similarly to processing, with more intensive processing (PI-75) of barley improving starch digestion, feed efficiency, and NEg without negatively affecting rumen pH.

Effects of a limited period of iron supplementation on the growth performance and meat colour of dairy bull calves for veal production

The effects of restricting iron intake for the final 60 days of a 180-day growth trial on growth performance, nutrient digestibility, slaughter performance and meat quality of dairy bull calves used in veal production were evaluated in this study. Twenty-four newborn Holstein bull calves with an average weight of 41.0 ± 1.62 kg were randomly assigned to two groups of n = 12 calves/group. Calves in the Control group were fed a basal diet that included a milk replacer and pellet feed for 180 days. The iron level in the basal diet was 50 mg/kg. Calves in the Treatment group received the basal diet supplemented with 70 mg/kg iron for the first 120 days, then received the basal diet for the remaining 60 days. Five calves from each group were slaughtered at the end of the trial, and samples of the M. longissimus dorsi and rumen fluid were collected. No differences were found in dry matter intake, growth performance or digestibility and metabolism of nutrients between the two groups (P > 0.05). The dietary iron regimen did not affect the concentrations of blood urea nitrogen, total protein, albumin, or glucose (P > 0.05); however, the haemoglobin content increased with the supplementation of iron in the diet (P < 0.05). Compared with the Control group, increasing dietary iron increased the meat percentage (P < 0.05) rather than the meat nutritional composition or quality of veal.

Effect of including high-lipid by-product pellets in substitution for barley grain and canola meal in finishing diets for beef cattle on ruminal fermentation and nutrient digestibility

The objective was to determine the effect of replacing barley grain and canola meal with high-lipid by-product pellets (HLBP; 14.6% CP, 29.8% NDF, 9.0% fat, and 5.52 MJ NE/kg in DM) on DMI, ruminal fermentation, nutrient flow at the omasal canal, and nutrient digestibility. Four ruminally cannulated and ovariectomized Hereford × Gelbvieh heifers (initial BW of 631.9 ± 23.3 kg; mean ± SD) were used in a 4 × 4 Latin square design. Periods consisted of 28 d, including 10 d for diet transition, 11 d for dietary adaptation, and 7 d for measurements. Heifers were fed a typical finishing diet consisting of 89% of concentrate (barley grain and canola meal; CONT), 6% of barley silage, and 5% of mineral and vitamin supplement (on DM basis). Dietary treatments consisted of a CONT or diets where 30% (HLBP30), 60% (HLBP60), and 90% (HLBP90) of the barley grain and canola meal were replaced with HLBP. Dry matter intake was not affected by treatment ( > 0.10). Total short-chain fatty acid concentration and molar proportions of acetate, propionate, and butyrate ( > 0.10) among treatments and ruminal ammonia did not differ ( > 0.10) among treatments, and ruminal ammonia increased ( = 0.03) linearly with increasing HLBP inclusion rate in the diet. Mean and maximum pH increased, whereas the duration and area that pH was below 5.8, 5.5, and 5.2, thresholds used for mild, severe, and acute ruminal acidosis, respectively, decreased linearly ( ≤ 0.05) with increasing rates of inclusion of HLBP. Organic matter flow at the omasal canal increased linearly ( = 0.03) with increasing HLBP inclusion rate in the diet. However, OM digestibility coefficients and apparent ruminal NDF and ADF digestibility yielded negative values for some animals, especially those fed HLBP90, indicating that ruminal digestibility was underestimated. Total tract OM digestibility decreased linearly ( < 0.01) with increasing inclusion rates of HLBP. This study showed that HLBP inclusion in substitution for barley grain and canola meal linearly decreases the severity of ruminal acidosis in cattle fed a typical grain-based finishing diet. However, total tract nutrient digestibility was negatively affected.

Evaluation of a phase-feeding strategy utilizing high-lipid high-fibre byproduct pellets in diets for feedlot steers

Two studies were conducted to evaluate the provision of high-lipid high-fibre byproduct pellets when used as a partial replacement (60% in Study 1 and 30% in Study 2; HLP) for barley grain and canola meal in finishing diets (BAR). The HLP was fed for the last 49, 98, or 147 d (HLP49, HLP98, and HLP147, respectively) in Study 1, and for the last 60 or 120 d in Study 2 (HLP60 and HLP120, respectively) or the last 60 d with additional canola oil (HLP60CO). The statistical model included the fixed effects of diet, period, and the interaction. Steers fed BAR147 had the greatest average daily gain (ADG) (P < 0.01) and G:F (P = 0.01). The HLP147 had the greatest dry matter intake (DMI) during the first 49 d but least during the last 49 d of the finishing phase (treatment × period; P < 0.01). Hot carcass weight for BAR147 and HLP49 were the heaviest (P = 0.04). In Study 2, DMI and ADG were not affected (P > 0.05), but hot carcass weight was greater for BAR120 and HLP60 than HLP120 and HLP60CO. Inclusion of high-fibre high-lipid byproduct pellets in the latter part of the finishing period may improve carcass yield grade without affecting ADG and G:F.

The bio refinery; producing feed and fuel from grain

It is both possible and practicable to produce feed and fuel from grain. Using the value of grain to produce renewable energy for transport, while using the remaining protein content of the grain as a valuable protein source for livestock and for fish, can be seen as a complimentary and optimal use of all the grain constituents. Consideration must be given to maximise the value of the yeast components, as substantial yeast is generated during the fermentation of the grain starch to produce ethanol. Yeast is a nutritionally rich feed ingredient, with potential for use both as feed protein and as a feed supplement with possible immunity and gut health enhancing properties. Bioprocessing, with the consequent economies of scale, is a process whereby the value of grain can be optimised in a way that is traditional, natural and sustainable for primarily producing protein and oil for feed with a co-product ethanol as a renewable fuel.

Effect of wheat dried distillers grains and enzyme supplementation on growth rates, feed conversion ratio and beef fatty acid profile in feedlot steers

The objectives of this study were to determine: (1) the effect of wheat dried distillers grain with solubles (DDGS) inclusion, and (2) dietary feed enzyme (FE; Econase XT) supplementation in a finishing diet containing wheat DDGS on fatty acid profile of the pars costalis diaphragmatis muscle of beef cattle. A total of 160 crossbred yearling steers with initial BW of 495 ± 38 kg were blocked by BW and randomized into 16 pens (10 head/pen). The pens were randomly assigned to one of the four treatments: (1) control (CON; 10% barley silage and 90% barley grain-based concentrate, dry matter (DM) basis); (2) diet containing 30% wheat DDGS in place of barley grain without FE (WDG); (3) WDG diet supplemented with low FE (WDGL; 1 ml FE/kg DM); and (4) WDG diet supplemented with high FE (2 ml FE/kg DM). The pars costalis diaphragmatis muscle samples were collected from cattle at slaughter at the end of the finishing period (120 days) with a targeted live weight of 650 kg. No differences in organic matter intake, final BW and average daily gain were observed among treatments. However, steers fed WDG had greater (P<0.01) feed conversion ratio than those fed CON, and increasing FE application in wheat DDGS-based diets tended (P<0.10) to linearly decrease feed conversion ratio. In assessing the effects of including WDG diets without FE, concentration of total polyunsaturated fatty acids (PUFA) in muscle tended to be greater (P<0.10) for steers fed WDG than steers fed CON. In addition, inclusion of wheat DDGS into the diet increased (P<0.05) concentration of CLA and vaccenic acid (VA) in muscle and also resulted in a higher (P<0.05) ratio of n-6/n-3 PUFA compared with that from steers fed CON diet. Increasing FE application in wheat DDGS-based diets did not modify the concentrations of individual or total fatty acids. These results suggest that inclusion of wheat DDGS in finishing diets may improve fatty acid profile of beef muscle which could benefit human health.

Effect of calcium oxide inclusion in beef feedlot diets containing 60% dried distillers grains with solubles on ruminal fermentation, diet digestibility, performance, and carcass characteristics

Two experiments were conducted to determine the effect of increasing dietary CaO on ruminal fermentation, diet digestibility, performance, and carcass characteristics of feedlot steers fed 60% dried distillers grains with solubles ( DDGS: ). In Exp. 1, 120 steers were allotted by weight (355 ± 7.9 kg) to 1 of 4 treatments containing 60% DDGS, 20% corn silage, 13.5 to 14.4% ground corn, 4% supplement, and 0 to 2.5% limestone on DM basis to determine the effects of CaO on performance and carcass characteristics. Treatments consisted of 0, 0.8, 1.6, or 2.4% CaO inclusion in the diet (DM basis), with CaO replacing limestone. Steers were slaughtered at a target BW of approximately 641 kg. In Exp. 2, 4 steers (initial BW = 288 ± 3 kg) were randomly allotted to the same diets in a 4 × 4 Latin square design (14-d periods) to determine the effects of CaO on ruminal pH, VFA, and nutrient digestibility. Statistical analyses were conducted using the MIXED procedure of SAS. Inclusion of CaO at 0.8, 1.6, and 2.4% increased ADG by 5.0, 3.9, and 0%, respectively, compared to 0% CaO (quadratic; P = 0.03). Intake was linearly decreased (P = 0.04) and G:F was linearly increased (P = 0.02) by CaO inclusion. Dressing percentage increased as CaO increased from 0 to 1.6% and then decreased for 2.4% CaO (quadratic; P < 0.01). In Exp. 2, steers fed 0% CaO had the greatest prefeeding ruminal pH, steers fed 0 and 0.8% CaO exhibited the most rapid postfeeding decline in ruminal pH, and steers fed 2.4% CaO exhibited a relatively stable ruminal pH throughout the 24-h period (treatment × time; P ≤ 0.01). Acetate, butyrate, and total VFA concentrations increased linearly (P ≤ 0.05) at 0, 3, 6, and 12 h postfeeding with increasing CaO. Propionate at 3 h postfeeding increased from 0 to 1.6% CaO and decreased from 1.6 to 2.4% CaO (quadratic; P = 0.10). Urine pH increased linearly (P ≤ 0.01) while urine output and urine ammonia decreased linearly (P ≤ 0.05) as CaO inclusion increased. Apparent NDF digestibility tended to increase (P = 0.07) and ADF digestibility did (P = 0.01) increase linearly with increasing concentrations of CaO. In conclusion, CaO improved ruminal pH variation, increased fiber digestibility, and decreased metabolic acid load in cattle fed 60% DDGS-based diets. Inclusion of CaO up to 1.6% was effective in improving performance of feedlot cattle.

Using a fibrolytic enzyme in barley-based diets containing wheat dried distillers grains with solubles: ruminal fermentation, digestibility, and growth performance of feedlot steers

Two experiments were conducted to evaluate the effects of adding an exogenous fibrolytic enzyme (FE) on ruminal pH and fermentation, digestibility, and growth performance of feedlot beef cattle fed a finishing diet containing wheat dried distillers grains with solubles (DDGS). In Exp. 1, 4 ruminally cannulated Angus heifers (average BW of 807 ± 93.9 kg) were used in a replicated 4 × 4 Latin square design. Treatments were 1) control (CON; 10% barley silage and 90% barley grain-based concentrate), 2) CON diet substituting 30% wheat DDGS for barley grain (WDG), 3) WDG diet supplemented with low FE (WDGL), and 4) WDG diet supplemented with high FE (WDGH). Heifers fed WDG had less (P = 0.01) total tract DM digestibility than heifers fed CON. Increasing FE linearly (P < 0.05) increased starch digestibility without affecting digestibility of other nutrients. Addition of FE also reduced (P = 0.03) ruminal ammonia-N (NH3-N) concentration but did not affect VFA concentration. Moreover, application of FE to wheat DDGS linearly increased in situ ruminal DM (P < 0.01) and NDF (P = 0.02) disappearance after 48 h of incubation. In Exp. 2, 160 yearling steers (initial BW = 495 ± 37.9 kg) were fed the same diets as in Exp. 1. No differences in DMI, final BW, ADG, dietary NEg, or carcass characteristics were observed among diets. However, the steers fed WDG had less (P < 0.05) G:F and greater number of (P < 0.01) abscessed livers than steers fed CON. Increasing FE application in wheat DDGS diets did not affect DMI, final BW, or ADG but tended (P < 0.09) to linearly improve feed efficiency and decreased (P = 0.03) the incidence of abscessed livers. These results demonstrated adverse effects of including wheat DDGS in finishing diets on feed digestion, feed efficiency, and animal health. Application of FE in wheat DDGS-based diets potentially improved starch digestion, protein metabolism in the rumen, feed efficiency, and animal health.

Effect of low-oil corn dried distillers’ grains with solubles on growth performance, carcass traits and beef fatty acid profile of feedlot cattle

He, M. L., Xu, L., Yang, W. Z., Gibb, D. and McAllister, T. A. 2014. Effect of low-oil corn dried distillers’ grains with solubles on growth performance, carcass traits and beef fatty acid profile of feedlot cattle. Can. J. Anim. Sci. 94: 343–347. The objective of this study was to investigate the effects of dietary inclusion of low-oil corn dried distillers’ grains with solubles (LO-DDGS) on growth, carcass traits and beef fatty acids profiles of finishing feedlot cattle. One hundred and eighty British crossbred steers (450±28.5 kg; six pens/treatment) were offered barley grain-barley silage as the control diet with LO-DDGS replacing barley grain at 200 and 300 g kg−1 dry matter basis in treatment diets. Compared with control, LO-DDGS at 200 g kg−1 did not affect growth performance or carcass traits, whereas at 300 g kg−1 it decreased (P<0.05) gain:feed, but increased (P<0.05) levels of desirable fatty acids in beef. LO-DDGS can replace 200 g kg−1 barley grain in finishing feedlot diets without undesirable impacts on growth performance or carcass traits.

Effect of ensiled mulberry leaves and sun-dried mulberry fruit pomace on finishing steer growth performance, blood biochemical parameters, and carcass characteristics

Fifty-one Simmental crossbred steers (357.0±16.5 kg) were used to compare a standard total mix ration (TMR) with variants on animal performance, ruminal fermentation, blood biochemical parameters, and carcass characteristics. Corn grain and cotton seed meal were partially replaced by ensiled mulberry leaves (EML) or sun-dried mulberry fruit pomace (SMFP). Experimental diets had similar amounts of crude protein (CP), acid detergent fiber (ADF), and metabolizable energy (ME). Animals were divided into three groups: control group (CONT), 8% EML group, and 6.3% SMFP group. Performance, including average daily weight gain (ADG), and dry matter intake (DMI), was measured. Blood and rumen samples were collected at the end of the experiment (16 weeks). There were no differences in final body weight (P = 0.743), ADG (P = 0.425), DMI (P = 0.642), or ADG/DMI (P = 0.236) between the groups. There were no differences (P = 0.2024) in rumen pH values; ammonia N was lower (P = 0.0076) in SMFP than in the EML and CONT groups. There were differences in the concentrations of total and individual volatile fatty acids, while no differences were determined in blood biochemical parameters (i.e., plasma glucose, urea concentrations, triglycerides, total protein, insulin, IgG, alanine transaminase, and aspartate aminotransferase, P ≥ 0.098). No differences were observed in carcass characteristics (P ≥ 0.513), tenderness (P = 0.844), adipose and lean color values (P ≥ 0.149), and chemical composition (P ≥ 0.400); however, intramuscular fat was lower in the EML and SMFP groups compared to the CONT animals (P = 0.034). In conclusion, diets supplemented with these two mulberry products in an isocaloric and isonitrogenous manner have similar effects to corn grain and cotton seed meals on steer performance, blood biochemical parameters and carcass characteristics, with the exception of ruminal VFA concentrations and lower intramuscular fat content.

Short Communication: Use of high-lipid by-product pellets as a partial replacement for barley grain and canola meal in finishing diets for beef steers

Górka, P., McKinnon, J. J. and Penner, G. B. 2013. Short Communication: Use of high-lipid by-product pellets as a partial replacement for barley grain and canola meal in finishing diets for beef steers. Can. J. Anim. Sci. 93: 523–528. The objectives were to determine the effect of the inclusion rate (0%, CON; 30%, HLP30; 60%, HLP60) of high-lipid by-product pellets (HLP) as a partial replacement for barley grain and canola meal on feed intake and growth performance of steers (n=264). Dry matter intake and gain:feed ratio were greater (P<0.01) for HLP30 and HLP60 relative to CON. This study indicates that up to 60% of the barley grain and canola meal in finishing diets for steers can be replaced with HLP, although feed efficiency may be compromised.

Short Communication: Effects of supplemental canola meal and various types of distillers’ grains on growth performance of backgrounded steers

Yang, W. Z., Xu, L., Li, C. and Beauchemin, K. A. 2012. Short Communication: Effects of supplemental canola meal and various types of distillers’ grains on growth performance of backgrounded steers. Can. J. Anim. Sci. 93: 281–286. A growth study was conducted to investigate the effects of protein source on growth performance of backgrounded steers. Partly replacing barley grain with canola meal (CM), corn dried distillers’ grains with solubles (cDDGS) or fractionated corn dried distillers grains with solubles (fDDGS) increased averaged daily gain and feed conversion efficiency of backgrounded steers. Steers fed corn DDGS (cDDGS, fDDGS) improved feed conversion efficiency compared with steers fed wheat dried distillers’ grain with solubles (wDDGS). These results indicate that inclusion of protein ingredients in barley-based diets is necessary to improve growth performance of growing cattle. To maximize profits, the choice of protein source in cattle rations will depend upon availability and cost of ingredients.

Effect of high dietary levels of canola meal on growth performance, carcass quality and meat fatty acid profiles of feedlot cattle

He, M. L., Gibb, D., McKinnon, J. J. and McAllister, T. A. 2013. Effect of high dietary levels of canola meal on growth performance, carcass quality and meat fatty acid profiles of feedlot cattle. Can. J. Anim. Sci. 93: 269–280. This study investigated the effect of substituting canola meal (CM) for barley grain on growth performance, carcass quality and meat fatty acid (FA) profiles of feedlot cattle. Cross bred calves (n=140; 285±27 kg) were individually fed diets comprised of a barley grain based concentrate (including 5% supplement) and barley silage at ratios of 45:55 and 92:8 (DM basis) during growing and finishing periods, respectively. Pressed CM from Brassica napus, containing 11.4% residual oil and solvent-extracted CM derived from B. napus or Brassica juncea canola seed were compared. Canola meal was substituted for 0 (control), 15, or 30% barley grain (DM basis) in both growing and finishing diets. Regardless of diet, cattle did not differ (P>0.05) in average daily gain in either the growing or finishing period. For the overall feeding period, inclusion of 30% CM increased (P<0.01) DMI of cattle compared with 15% CM groups, but reduced (P<0.05) gain: feed (G:F) as compared with control and 15% B. juncea and 15% pressed CM. Gain: feed of cattle fed CM was also reduced (P<0.05) during the finishing period as compared with the control diet with this reduction being more notable at the 30% level. Carcass quality and incidence of liver abscesses were not affected (P>0.05) by inclusion of CM. Inclusion of 30% pressed CM resulted in higher (P<0.05)%FAME of total polyunsaturated fatty acid, n-3, alpha-linolenic acid and conjugated linoleic acid (CLA), and a decrease (P<0.05) in n-6/n-3 ratio in the pars costalis diaphragmatis muscle as compared with the control diet. In conclusion, inclusion of CM did not alter the growth performance or G:F of beef cattle during the growing period, but did lower G:F during the finishing period. The inclusion of 15 or 30% solvent-extracted CM did not alter carcass quality, whereas 30% pressed CM increased the levels of desirable fatty acids (i.e., n-3 and CLA) in beef.

Triticale dried distillers' grain increases alpha-linolenic acid in subcutaneous fat of beef cattle fed oilseeds

This study investigated the effect of triticale dried distillers' grain with solubles (DDGS), flax (FS) and sunflower (SS) seed on growth and the fatty acid profile of subcutaneous (SQ) fat in individually housed steers (n = 15 per diet) fed ad libitum (DM basis); (1) control (CON) 90% barley grain + 10% barley silage; or substitution of barley grain for: (2) 30% DDGS; (3) 10% FS; (4) 30% DDGS + 8.5% FS; (5) 10% SS and (6) 30% DDGS + 8.5% SS. Oilseeds in the combination diets were reduced to maintain diet lipid levels below 9% DM and to determine if favorable changes in the fatty acid profile could be maintained or enhanced at reduced levels of oilseed. Plasma and SQ fat biopsies were collected at 0, 6, and 12 weeks. Inclusion of DDGS decreased (P < 0.05) average daily gain, feed conversion and backfat thickness. Feeding FS increased (P < 0.05) plasma ALA compared to CON and SS and consistently increased (P < 0.01) ALA and non-conjugated and non-methylene interrupted dienes (NCD), whereas SS tended to decrease ALA in fat. Inclusion of DDGS with FS further increased (P < 0.02) ALA and decreased (P < 0.05) NCD and 18:1-t10 in fat. The fact that the levels of n-3 fatty acids in SQ fat from steers fed DDGS + FS were higher than those obtained with FS alone, has obvious benefits to the practical cost of favorably manipulating fatty acid profiles in beef.