Barley Silage Research Articles

Intake, gain and carcass traits of Hereford and Charolais bulls offered diets based on triticale, barley and grass silages

Total mixed rations (TMR) based on grass silage (GS), triticale silage (TS), mixture of GS and TS, barley silage (BS) and mixture of GS and BS were fed to fifty Hereford (HF) and fifty Charolais (CH) bulls. The proportion (g kg-1 dry matter [DM]) of the silages in the TMRs were as follows: (1) GS (600); (2) TS (600); (3) GS (300) and TS (300); (4) BS (600); (5) GS (300) and BS (300). Concentrate proportion was 400 g kg-1 DM. According to feed analyses, the GS had 15 and 8% higher metabolizable energy (ME) concentration as well as 51 and 49% higher crude protein (CP) concentration compared to TS and BS, respectively. Average DM intake (DMI) on TS and BS containing diets was higher compared to GS as a sole forage (p=0.001). Compared to the TS based rations the use of BS rations increased daily DMI by 5% (p<0.05). In CH bulls, DMI decreased 0.8 kg d-1when GS partially replaced TS or BS while in HF bulls the use of silage mixtures slightly increased DMI (0.23 kg d-1). The live weight gain (LWG) and carcass gain of the CH bulls were 5 and 26% higher, respectively, compared to the HF bulls. Inclusion of GS in the diet increased LWG and carcass gain with TS but decreased them with BS (interaction p<0.01). The experiment demonstrated lower feeding value of TS compared to BS in the diet of the bulls. Whole crop silage based rations increased DMI compared to GS as a sole forage in the TMR. When GS partially replaced TS or BS, interactions in LWG and carcass gain results demonstrated higher feeding value for BS and lower for TS compared to GS. Feeding treatments had only minor effects on carcass traits of the bulls.

Optimum roughage proportion in barley-based feedlot cattle diets: growth performance, feeding behavior, and carcass traits.

High grain diets are fed to finishing beef cattle to maximize animal performance in a cost-effective manner. However, a small amount of roughage is incorporated in finishing diets to help prevent ruminal acidosis, although few studies have examined optimum roughage inclusion level in barley-based diets. The objective of the study was to evaluate the effects of roughage proportion in barley-based finishing diets on growth performance, feeding behavior, and carcass traits of feedlot cattle. Crossbred beef steers (n = 160; mean body weight ± SD, 349.7 ± 21.4 kg) were allocated to 20 pens that were assigned randomly to four dietary treatments (five pens of eight steers per treatment). The treatment diets contained barley silage at 0%, 4%, 8%, and 12% of dietary dry matter (DM). The remainder of the diets (DM basis) consisted of 80%, 76%, 72%, and 68% barley grain, respectively, 15% corn dried distiller's grains, 5% mineral and vitamin supplement, and 32 mg monensin/kg diet DM. The diets were fed as total mixed rations for ad libitum intake (minimum of 5% refusal) once per day. Cattle were weighed on 2 consecutive days at the start and end of the experiment and on 1 d every 3 wk throughout the experiment (124 d). Two pens for each treatment group were equipped with an electronic feeding system (GrowSafe Systems Ltd., Calgary, Alberta) to monitor feed intake and feeding behavior of individual cattle. The data for dry matter intake (DMI), average daily gain (ADG), gain:feed (G:F) ratio, and carcass traits were analyzed as a completely randomized design with fixed effect of barley silage proportion and pen replicate as experimental unit. Feeding behavior data were analyzed similarly, but with animal as experimental unit. Averaged over the study, DMI increased linearly (11.1, 11.3, 11.7, 11.8 kg/d; P = 0.001) as barley silage proportion increased from 0%, 4%, 8%, and 12% of DM, but ADG was not affected (carcass-adjusted,1.90, 1.85, 1.87, 1.89 kg/d; P ≥ 0.30). Consequently, G:F ratio decreased linearly (carcass-adjusted, 168.9, 163.8, 158.5, 160.6 g/kg DMI; P = 0.023). When averaged over the study, proportion of barley silage in the diet had no linear or quadratic effects (P > 0.10) on meal frequency, duration of meals, intermeal duration, or meal size, but eating rate decreased linearly with increasing silage proportion (P = 0.008). There was no diet effect on liver abscesses (P ≥ 0.92), and effects on carcass characteristics were minor or nonexistent. We conclude that increasing the proportion of barley silage in a feedlot finishing diet at the expense of barley grain to minimize the incidence of ruminal acidosis may decrease feed conversion efficiency.

3-Nitrooxypropanol supplementation had little effect on fiber degradation and microbial colonization of forage particles when evaluated using the in situ ruminal incubation technique

3-Nitrooxypropanol (3-NOP) is an investigational compound that acts as an enzyme inhibitor to decrease ruminal methanogenesis. We hypothesized that when feeding 3-NOP to cattle fed a high-forage diet, H2 would accumulate in the rumen, which could suppress microbial colonization of feed particles and fiber degradation. Therefore, the study investigated the effects of supplementing a high-forage diet with 3-NOP on ruminal fiber degradability and microbial colonization of feed particles using the in situ technique. Eight ruminally cannulated beef cattle were allocated to 2 groups (4 cattle/group) in a crossover design with 2 periods and 2 dietary treatments. The treatments were control (basal diet) and 3-NOP (basal diet supplemented with 3-NOP, 150 mg/kg of dry matter). The basal diet consisted of 45% barley silage, 45% chopped grass hay, and 10% concentrate (dry matter basis). Samples of dried, ground barley silage and grass hay were incubated in the rumen of each animal for 0, 4, 12, 24, 36, 48, 96, 120, 216, and 288 h to determine neutral detergent fiber (NDF) degradation kinetics. An additional 2 bags were incubated for 4 and 48 h to evaluate the bacterial community attached to the incubated forages. Dietary supplementation of 3-NOP decreased (-53%) the dissolved methane concentration and increased (+780%) the dissolved H2 concentration in ruminal fluid, but did not substantially alter in situ NDF degradation. The addition of 3-NOP resulted in a decrease in the α-diversity of the microbial community with colonizing communities showing reduced numbers of amplicon sequence variants and phylogenetic diversity compared with control diets. Principal coordinate analysis plots indicated that forages incubated in animals fed 3-NOP resulted in highly specific changes to targeted microbes compared with control diets based on unweighted analysis (considering only absence and presence of taxa), but did not alter the overall composition of the colonizing community based on weighted UniFrac distances; unchanged relative abundances of major taxa included phyla Bacteroidetes, Firmicutes, and Fibrobacteres. The effect of 3-NOP on colonizing methanogenic microbes differed depending upon the forage incubated, as abundance of genus Methanobrevibacter was decreased for barley silage but not for grass hay. In conclusion, 3-NOP supplementation of a high-forage diet decreased ruminal methanogenesis and increased dissolved H2 concentration, but had no negative effects on ruminal fiber degradation and only minor effects on relative abundances of the major taxa of bacteria adhered to forage substrates incubated in the rumen.

Changes in the fatty acid composition of steer subcutaneous fat, including biohydrogenation products, are minimal when finished on combinations of corn and barley grains and silages

Corn production in Western Canada has increased with development of short-season varieties partially offsetting the use of barley as a silage and grain source. The current study evaluated effects of silage and cereal-grain source on subcutaneous fat (SCF) composition of finishing cattle. Steers (465 ± 28.0 kg) were assigned to 24 pens (12 steers per pen) in a 2 × 3 factorial design for an 89 d finishing study. Diets contained corn silage or barley silage at 8% [dry matter (DM)] combined either dry-rolled barley grain (BG; 86% of DM), corn grain (CG; 85% of DM), or an equal blend of BG and CG (85% of DM). Bone-in ribeyes were collected from four steers per pen, and subcutaneous fatty acids were analyzed by gas chromatography. Feeding dry-rolled CG increased dietary fat and 18:2n-6 concentrations, resulting in small increases in 18:2n-6, total n-6 fatty acids, and n-6/n-3 ratios in SCF (P < 0.05). There were no changes in proportions of major trans-18:1 isomers (t10-18:1 or t11-18:1), the main natural isomer of conjugated linoleic acid (cis9,t11–18:2), or n-3 fatty acids. Substitution of dry-rolled CG for BG in finisher diets can, therefore, be done without substantially altering the fatty acid composition of beef fat, including polyunsaturated fatty acid biohydrogenation products.

Use of barley silage or corn silage with dry-rolled barley, corn, or a blend of barley and corn on predicted nutrient total tract digestibility and growth performance of backgrounding steers

The objective of this study was to determine the effects of feeding barley silage (BS) or corn silage (CS) with dry-rolled barley (BG), dry-rolled corn (CG), or a blend of barley and corn grain (BCG), on growth performance and nutrient digestibility, the latter predicted using near-infrared spectroscopy for backgrounding cattle. Steers (n = 288) were stratified by body weight (BW) into 24 pens and pens were randomly assigned to one of six treatments (n = 4) in a 2 × 3 factorial design. Main factors included BS or CS in combination with BG, CG, or BCG. There were no silage × grain interactions. Dry matter intake (DMI; P = 0.018) and final BW (P = 0.004) were greater for steers fed CS than BS, but average daily gain (1.01 kg d−1) and gain-to-feed ratio (0.10 kg kg−1) were not affected by silage or grain source. Steers fed CS also had greater dry matter, organic matter, crude protein (CP), acid detergent fiber (ADF), starch, and gross energy digestibility values (P < 0.01) than BS. Feeding BG increased starch, neutral detergent fiber, ADF, and CP digestibility values (P ≤ 0.01) over CG and BCG. Relative to BS, feeding CS increased DMI, final BW, and nutrient digestibility, whereas dry-rolled BG improved nutrient digestibility when compared with CG and BCG in backgrounding diets.

Using molecular microbial ecology to define differential responses to the inoculation of barley silage

Previously, we investigated the impact of a mixed Lactobacillus buchneri, Lactobacillus plantarum, and Lactobacillus casei inoculant on fermentation and aerobic stability of barley silage over two years in 2009 and 2010. In 2009, a classical response to inoculation was obtained with an increase in acetic acid concentration of silage ensiled in both mini- and bag silos. In 2010, this classical response was not observed in mini-silos but was observed in bag silos. The objective of this study was to determine if molecular microbial ecology could explain the differential responses to the inoculation of barley silage between the two years. The Illumina MiSeq sequencing results showed that inoculation increased Lactobacillus and lowered Pediococcus, Weissella, and Leuconostoc in both types of silos in 2009. However, a similar trend was not observed in mini-silos, but was instead observed in bag silos in 2010. Inoculation did not alter the core fungal community in either silo type in either year. Cladosporium, Leptosphaeria, and Cryptococcus were abundant in fresh forage, but were superseded by Pichia and Kazachstania after ensiling. Our results suggest that changes in silage chemistry corresponded to differences observed in microbial ecology. Inoculation may have less impact when using more mature crops with shorter ensiling times.

Optimum roughage proportion in barley-based feedlot cattle diets: total tract nutrient digestibility, rumination, ruminal acidosis, short-chain fatty absorption, and gastrointestinal tract barrier function.

Cattle need physically effective fiber to promote rumination and maintain rumen health, but economics favor the use of low-roughage feedlot diets. The study investigated the optimum barley silage proportion in barley-based finishing diets. Apparent total-tract digestibility (4-d total fecal collection), chewing behavior (6-d video recording), ruminal pH (6-d indwelling pH recording), and fermentation (1 day, sampling 0, 3, 6, 12, and 18 h postfeeding), short-chain fatty acid (SCFA) absorption (washed reticulo-rumen technique), gastrointestinal tract barrier function (marker infusion), and blood variables (catheters) were measured. Eight ruminally fistulated crossbred beef heifers (653 ± 44.2 kg; mean starting body weight [BW] ± SD) were used in a replicated 4 × 4 Latin square design with 28-d periods. Dietary treatments were 0%, 4%, 8%, and 12% of dietary dry matter (DM) as barley silage, with diets containing 80%, 76%, 72%, and 68% barley grain, respectively. Increasing silage proportion decreased dietary starch content from 49.0% to 43.1% DM, while neutral detergent content increased from 22.7% to 25.1% DM. Silage proportion had no effect on DM intake, but apparent DM digestibility decreased quadratically (86.0%, 82.1%, 81.1%, 79.5% for the four diets, respectively; P < 0.001). Although, silage proportion had no effect on eating activity, rumination time increased quadratically (246, 289, 302, 316 min/d; P = 0.04). Increased silage proportion increased minimum (5.07, 5.27, 5.29, 5.41; quadratic, P = 0.011) and mean (5.61, 5.87, 5.93, 5.95; quadratic, P = 0.007) ruminal pH, and there was a quadratic (P ≤ 0.047) decrease in duration and area under the pH acidosis threshold curves of 5.8, 5.5, and 5.2. Although increasing silage proportion decreased ruminal acidosis, it was not completely eliminated even with a diet containing 12% silage DM. SCFA concentration in ruminal fluid was not affected by diet, but silage proportion quadratically (P ≤ 0.088) increased ruminal acetate:propionate. There was no effect of diet on absolute or fractional rates of absorption of acetate, propionate, butyrate or total SCFA, and no effect on gastrointestinal barrier function or blood measurements. In conclusion, responses to roughage level were mostly quadratic with greatest improvements in acidosis variables between 0% and 4% barley silage, with incremental improvements with further increases in silage levels. The study showed a trade-off between maximizing digestibility and energy intake to promote animal performance and minimizing the risk of acidosis.

Nutritive value for high-yielding lactating cows of barley silage and hay as a substitute for wheat silage and hay in low-roughage diets

We assessed the effects of replacing wheat silage and hay with barley silage and hay in total mixed rations (TMRs) on: eating behavior, digestibility, and performance of individually fed high-yielding lactating cows. The barley cultivar Ma’anit and the wheat cultivar Omer were grown by dryland farming (210 mm precipitation) in a commercial field with sandy loam soil. The two cultivars were harvested simultaneously for silage or hay at a similar dry matter (DM) content (35.6%). Barley yields exceeded wheat yields by 19% (5.68 vs. 4.79 t DM/ha, P = 0.01). Two-thirds of each crop's DM yield was chopped and transferred for direct ensiling in polyethylene-wrapped bales, and one-third was wilted in the field for 2 weeks and then pressed into hay bales. The chemical composition and in-vitro DM digestibility of the wheat and barley silages and hays were similar. The two experimental TMRs contained either barley silage (280 g/kg DM) and hay (60 g/kg DM) or similar contents of wheat silage and hay, as the sole source of roughage. High-yielding multiparous Israeli Holstein cows were paired into two experimental groups of 21 cows each and fed either wheat- or barley-based TMR ad libitum for 28 days. DM intake of cows fed the wheat TMR was higher than that of the barley TMR-fed cows (28.0 vs. 27.5 kg/day) due to a faster eating rate (137.9 vs. 132.9 g DM/min) and larger meal size. Energy corrected milk production was similar in the two groups (42.4 and 42.8 kg/day), while milk fat yield was higher in barley-fed cows than wheat-fed cows (1.62 vs. 1.57 kg/day). Daily rumination time of the barley-fed cows was longer (577 vs. 537 min/day) and their rumen pH higher during the day and night (P < 0.01) compared to wheat-fed cows. Consequently, in-vivo DM digestibility and neutral detergent fiber digestibility were higher in the barley-fed cows. Our results thus show the benefit of barley as an alternative forage crop to wheat in semiarid regions, and its advantage as a substitute for wheat as silage and hay for high-yielding lactating cows’ TMR.

Association of leptin genotype with growth performance, adipocyte cellularity, meat quality, and fatty acid profile in beef steers fed flaxseed or high-oleate sunflower seed diets with or without triticale dried distiller's grains.

Leptin genotypes can be identified as homozygous normal (CC), homozygous mutant (TT), and heterozygous (CT) based on a single-nucleotide polymorphism in exon 2 of the leptin gene, which has been associated with feed intake and fat deposition in cattle. The experiment was designed as 2 × 2 × 2 factorial with three main factors: (1) genotype (CT or TT) and diets fed 2) with or without triticale dried distiller's grains with solubles (DDG), and 3) with either flaxseed (FS) or high-oleate sunflower seed (SS). Evaluations included growth performance, subcutaneous fat deposition, adipocyte cellularity, meat quality, and fatty acid (FA) profile of various depots. Beef steers (n = 40, 459 ± 31 kg) of either CT or TT genotypes were housed in individual pens with ad libitum access to one of the four diets: 75% steam-rolled barley + 10% barley silage with 10% FS or SS (non-DDG diets, NDG) and 46.5% barley + 10% barley silage + 30% DDG, with 8.5% FS or SS, all on a dry matter basis. Growth performance, ultrasound subcutaneous fat thickness, rib eye area (REA), and plasma FA were measured prior to and during the finishing period. At slaughter, samples of subcutaneous fat, perirenal fat, and Longissimus thoracis (LT) muscle were collected for FA analysis and carcass and meat quality were measured. Compared with CT cattle, TT tended to have less (P = 0.06) C18:2-c9,t11 (rumenic acid) in plasma and subcutaneous fat and a greater proportion (P < 0.05) of C18:0 in subcutaneous, perirenal, and LT fat. Cattle with TT genotype also tended (P < 0.1) to have more total saturated and less unsaturated (USFA) and monounsaturated fats (MUFA) and had less (P = 0.04) linoleic acid in LT. Ultrasound fat thickness, REA, and average diameter of adipocytes in subcutaneous fat at 12 wk were not affected (P > 0.39) by genotype. Generally, carcass and meat quality were similar (P > 0.1) among diets, although adding FS tended to increase (P = 0.06) total USFA of subcutaneous fat including omega-3 FA (P < 0.001). For the high-fat diets evaluated, CT cattle would have more potential to produce beef with enhanced health benefits than would TT cattle.

Impact of molasses and microbial inoculants on fermentation quality, aerobic stability, and bacterial and fungal microbiomes of barley silage

This study aimed to investigate the effects of microbial inoculants (L) and molasses (M) on the bacterial and fungal microbiomes of barley silage after the aerobic stage. The addition of molasses and microbial inoculants improved the aerobic stability of barley silage. The ML silage, which had a low pH value and high lactic and acetic acid contents, remained aerobically stable for more than 216 h. The ML silage exhibited low bacterial and high fungal diversities. Microbial inoculants and molasses enriched the abundance of Lactobacillus in silage after aerobic exposure. The enrichment of L. buchneri was significant in ML silage at days 5 and 7 during the aerobic stage. The abundance of harmful microorganisms, such as aerobic bacterial including Acinetobacter, Providencia, Bacillus, and yeasts including Issatchenkia, Candida, and Kazachstania, were suppressed in ML silage. M and L had an impact on bacterial and fungal microbes, resulting in the improvement of fermentation quality and reduction of aerobic spoilage in barley silage.

Effects of Heterofermentative Lactic Acid Bacteria on the Ruminal Fermentation of Italian Ryegrass and Whole Crop Barley Silage

Effects of Heterofermentative Lactic Acid Bacteria on the Ruminal Fermentation of Italian Ryegrass and Whole Crop Barley Silage

Effects of Microbial and Organic Additives on Fermentation Quality and Aerobic Stability of Barley Silage

The goal of this study was to evaluate effects of various microbial and organic additives on chemical compositions, fermentation indices, and aerobic stability of barley silage. Youngyang barley harvested at 31.5% dry matter (DM), and ensiled into 20 L bucket silo for 0, 1, 3, 7, 48, and 100 d in quadruplicates with four additives following: sterile destilled water at 1% of fresh forage (CON); Lactobacillus plantarum at 1.2 x 105 cfu/g of fresh forage (CL); Lactobacillus buchneri at rate of 1.2 x 105 cfu/g fresh forage (LB); Fermented Persimmon Extract at 1% of fresh forage (FPE); and Essential Oil at 1% of fresh forage (EO). On 100 d of ensiling, CL and FPE silages had lower (p<0.05) DM than CON silage. Additionally, FPE silage had higher (p<0.05) crude protein than CON silage. All silages with additives, except EO, had higher (p<0.05) neutral detergent fiber (NDF) than CON silage. Silage treated with CL, LB, and FPE had lower in vitro DM digestibility than CON silage, and silages treated with LB and FPE had higher in vitro NDF digestibility (IVNDFD) on 100 d of ensiling. The PFE silage produced the highest (p<0.05) lactate during ensiling period, while LB silage produced the highest (p<0.05) acetate. All inoculated silages had higher (p<0.05) LAB count than control silage. Only CL silage had higher (p<0.05) yeast count than control silage, while the other silages were not differ compared to CON silage. The aerobic stability was higher (p<0.05) in LB and FPE silages than in CON silage. In conclusion, FPE could be an alternative additive to increase IVNDFD, fermentation indices, and aerobic stability of barley silage.

Effect of feeding barley or corn silage with dry-rolled barley, corn, or a blend of barley and corn grain on rumen fermentation, total tract digestibility, and nitrogen balance for finishing beef heifers.

Five ruminally cannulated heifers were used in an incomplete 6 × 6 Latin square design to determine the effects of cereal silage (barley vs. corn), cereal grain (barley vs. corn vs. a 50:50 blend of barley and corn), and their interaction (S × G) on dry matter intake, ruminal fermentation, total tract digestibility, nitrogen balance, and in situ degradation. Corn silage (CS) or barley silage (BS) was included at 8% of dietary dry matter (DM). Within each silage source, diets contained (DM basis) either dry-rolled barley (BG; 86%), dry-rolled corn (CG; 85%), or an equal blend of barley and corn (BLEND; 85%). Periods were 25 d, with 5 d of dietary transition, 13 d of dietary adaptation, and 7 d of data and sample collection. Samples collected included feed and refusals, total urine and feces, and ruminal fluid. All data were analyzed using the Mixed model of SAS with the fixed effects of silage, grain, and the S × G. Dry matter intake (P ≥ 0.19) and mean ruminal pH (P ≥ 0.096) were not affected by the silage, grain, or S × G. Total short-chain fatty acid concentrations were greater for BLEND than BG or CG (grain, P = 0.003) and for CS (silage, P = 0.009) relative to BS. The molar proportion of acetate was greater for BS-BG and BS-CG (S × G, P < 0.001), while molar proportion of propionate was greater for CS-BG (S × G, P < 0.001) relative to other silage and grain source combinations. Rumen ammonia-N concentration was greater for CG than BG, or BLEND (grain, P < 0.001), and greater for CS compared to BS (silage, P = 0.023). Apparent total tract digestibility of DM, organic matter, neutral detergent fiber, starch, and gross energy were greatest for BG (grain, P ≤ 0.035). Digestible energy content (Mcal/kg) was greater for BG (grain, P = 0.029) than CG and BLEND. Total nitrogen retention (g/d and % of intake) was greatest for CS-BG (S × G, P ≤ 0.033) relative to all other treatments. In situ degradation rates of DM, crude protein, and starch were greater for BG than CG (P ≤ 0.004). The potentially degradable fraction of DM, crude protein, and starch was greater for CG (P ≤ 0.031), while the undegradable fraction was greater for BG (P ≤ 0.046). For silage sources, CS had greater 24 h in situ DM digestibility (P = 0.009) and starch digestibility (24, 48, and 72 h incubations, P ≤ 0.034) relative to BS. Results suggest that while feeding a combination of CS and BG promotes propionate production and greater N retention; few other additive effects were observed.

86 Evaluation of ensiled triticale varieties (‘Taza’ and ‘Bunker’ Triticosecale) and barley (Hordeum vulgare) on performance of backgrounding beef steers

Abstract A 3-year study compared two triticale (Triticosecale) varieties, Bunker and Taza, with a conventional barley (Hordeum vulgare) fed as silage to backgrounding beef steers on the basis of crop dry matter (DM) yield, nutritive value, steer performance, and total daily feeding costs. Each year, 240 fall weaned beef steers were stratified by BW (308 ± 4.9 kg) and allocated to 1 of 3 replicated (n = 4) dietary treatments containing Bunker triticale, Taza triticale, or barley silage. Steers were fed a total mixed ration (TMR) consisting of silage (55–68%), barley grain (20–34%), supplement (5%), and (0.4–6%) canola meal (DM basis). Diets were formulated to be isonitrogenous and isocaloric to meet or exceed NRC (2001) requirements for TDN and CP. Crop DM yield of Taza (6750 kg DM ha-1) and Bunker triticale (6592 kg DM ha-1) was similar (P &amp;gt; 0.05), and both were greater (P = 0.01) than barley (6008 kg DM ha-1). Over 2 years, steer ADG, DMI, G:F, and the calculated NEm, and NEg did not differ (P &amp;gt; 0.05) among treatments. Cost per head per day was lowest for Taza fed steers at $1.26 hd-1 d-1, followed by Bunker silage at $1.33 hd-1 d-1, and Barley silage at $1.34 hd-1 d-1. Total cost of gain for Taza, Bunker, and barley fed steers was $0.84, $0.91, and $0.93, per kg of gain, respectively. Study results suggest that Taza and Bunker triticale silage can be used as an alternative to barley silage when fed to backgrounding beef steers.

PSIX-12 Screening of peptides for their impact of protease, protease dose and peptide dose on in vitro rumen dry matter digestibility

Abstract 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 &amp;lt; 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 &amp;lt; 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 &amp;lt; 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 &amp;lt; 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.

PSIX-11 Impact of a phytogenic feed additive on growth performance, feed intake and carcass traits of finishing steers

Abstract 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 &amp;lt; 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 &amp;lt; 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 &amp;lt; 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.

98 Effect of engineered biocarbon on rumen fermentation, nutrient digestibility, methane emissions, and rumen microbiota in beef heifers

Abstract The objective of this study was to examine the effect of engineered biocarbon (EB) on rumen fermentation, apparent total tract digestibility, methane (CH4) emissions and the rumen and fecal microbiome of Angus × Hereford heifers fed a barley silage-based diet. The experiment was a replicated 4 × 4 Latin square using 8 ruminally cannulated heifers (565 ± 35 kg initial BW). The basal diet contained 60% barley silage, 35% barley grain and 5% mineral supplement with EB added at 0% (control), 0.5%, 1.0%, or 2.0% (DM basis). Each period was 28-d consisting of 14-d adaptation and 14-d of measurements. Samples for profiling of the microbiome in rumen liquid, solids and feces were collected on d-15 before feeding. Rumen samples for fermentation characterization were taken at 0, 3, 6, and 12-h post feeding. Total collection of urine and feces was conducted from d-18 to 22. Heifers were housed in open-circuit respiratory chambers on d-26 to 28 to estimate CH4 emissions. Ruminal pH was recorded at 1-min intervals during CH4 measurements using indwelling pH loggers. Data were analyzed with the fixed effects of dietary treatment and random effects of square, heifer within square and period. Dry matter intake was similar across treatments (P = 0.21). NH3-N concentration and protozoa counts responded quadratically (P = 0.01) to EB. Minimum pH was increased (P = 0.04), and variation of pH was decreased (P = 0.03) by 2.0% EB. Total tract digestibility, N balance and CH4 production were not affected (P ≥ 0.17) by EB. EB affected the relative abundance of Fibrobacter (P = 0.05), Spirochaetaes (P = 0.01), Verrucomicrobia (P = 0.02), Tenericutes (P = 0.01), and Elusimicrobia (P = 0.02). Results suggest that at the examined concentrations, EB was ineffective at decreasing enteric CH4 emissions, however it altered the rumen microbiome.

PSXII-23 Effects of a recombinant fibrolytic enzyme on fiber digestion, ruminal fermentation, nitrogen balance and total tract digestibility of heifers fed a high forage diet

Abstract The objective of this study was to investigate the effects of a recombinant fibrolytic enzyme (RFE; xylanase XYL10C) on ruminal pH and fermentation characteristics, total tract digestibility and nitrogen balance in beef heifers. The experiment was a cross-over design with two treatments and two periods, using eight ruminal cannulated beef heifers. The treatments were a basal diet containing 60% barley silage, 30% barley straw and 10% supplement (DM basis) without (control) or with RFE. The RFE XYL10C was selected specifically for ruminants using a high throughput in vitro micro assay and was sprayed onto the barley straw at a rate of 6.6 × 104 IU/kg DM 24 h before feeding. The diet was prepared daily using a data ranger. Each period was 21 d, with a 14-d adaptation and 7-d sample collection period. The digestibility and nitrogen balance were measured by total fecal and urine collection. Data were analyzed using the PROC MIXED procedure of SAS with fixed effects of treatment, and random effects of period and heifer. Feed intake (8.9 kg/d) and total tract digestibility of DM (65.5%), NDF (57.2%) and ADF (51.2%) were not affected by RFE. Ruminal pH including mean (6.52), minimum (5.79), maximum (7.05), and duration of pH &amp;lt; 5.8 (0.64, h/d) did not differ between treatments. No treatment effects were observed for total VFA concentration (106 mM), molar proportion of acetate (68.2%) and propionate (17.5%) and acetate to propionate ratio (3.94). However, adding RFE vs. control tended (P &amp;lt; 0.08) to increase ruminal NH3-N concentration (5.75 vs. 5.23 mM) and endoglucanase activity (44.3 vs. 40.7 µmol glucose/min/mL wet rumen contents). There were no differences in nitrogen utilization and rumen microbial protein synthesis (90.7 g/d) between treatments. The results indicate that RFE XYL10C did not improve fiber digestion in heifers fed a high forage diet.

403 Using ruminally protected and unprotected Saccharomyces cerevisiae fermentation products as alternatives to antibiotics in finishing beef steers: growth performance and antimicrobial resistance

Abstract 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 &amp;lt; 0.10) to be greater in steers supplemented with eXPC compared with control (1.80 vs. 1.62 kg/d) with a trend (P &amp;lt; 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 &amp;lt; 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 &amp;lt; 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.

93 Feeding behavior as predictive traits of fertility and lifetime productivity in replacement beef heifers

Abstract Fertility and longevity traits in beef cows are difficult and expensive to measure. The use of other traits to predict fertility and longevity traits in beef cows will enable selection for efficient reproduction earlier in an animal’s life. The objective of this study is to identify feeding behaviours with predictive relationships to fertility, longevity, and lifetime productivity in beef cows. This study used 421 Bos taurus commercial replacement heifers born from 2004 to 2014 and followed over 1050 mating opportunities, 11 production cycles and 5 parities. Heifers were weaned at 6–7 mo of age and developed on a 90% barley silage, 10% rolled barley diet in pens equipped with 16 electronic feed bunks to monitor feed intake and feeding behaviors. Feed intake (FI), feeding frequency (FREQ), duration (DUR), head-down time (HD) and time-to-bunk (TTB) were collected over the course of the feeding trial. Phenotypic correlations indicate that as FI increased during the heifer development stage, so did subsequent cow pre-breeding and pre-calving body condition score (BCS; r = 0.43, 0.36 respectively) and total lifetime productivity (r = 0.40). As FREQ increased, pre-breeding and pre-calving BCS decreased (r = -0.16 and -0.20, respectively), as did calf birth weight (r = -0.15). As DUR increased, weak positive correlations were observed with days in herd (r = 0.10), age at first calving (r = 0.17) and calf birth weight (0.13). Increased HD would lead to increased pre-breeding and pre-calving BCS (r = 0.16, 0.23 respectively), and greater lifetime productivity (r = 0.16). Time-to-bunk was positively correlated with days in the herd (r = 0.15), and with decreased calf birth weight (r = -0.23) and pre-calving cow weight (r = -0.33). These feeding behaviour traits, collected early in life, are worthy of further investigation into multi trait regression, genetic correlations and genomic selection.