Short-season high-moisture shelled corn, snaplage, or corn silage as a partial replacement for dry-rolled barley grain or barley silage in western Canadian beef cattle finishing diets

Abstract The objective was to evaluate the replacement of barley-based ingredients with short-season high-moisture corn products on steer growth performance and carcass characteristics. Over 2 years, 320 beef steers (528�±�36.2�kg initial body weight) were assigned to 32 pens (4 pens/treatment/year). Treatments were finishing diets that contained dry-rolled barley grain and barley silage (BGBS; control), barley grain and corn silage (BGCS), high-moisture shelled corn and barley grain with barley silage (HCBS), or snaplage (included as a silage and grain source) with barley grain (SNAP). Steers were fed for 99 days and 72 days in years 1 and 2, respectively. Steers fed BGCS did not differ (P�≥�0.13) from BGBS for dry matter intake, average daily gain, gain:feed, or carcass characteristics. Steers fed HCBS had greater (P�≤�0.05) hot carcass weight and dressing percentage than BGBS. A lesser (P�=�0.02) proportion of steers fed SNAP had severe liver abscesses than BGBS. We concluded that corn silage can replace barley silage, 50% replacement of barley grain with high-moisture shelled corn may improve hot carcass weight, and replacement of barley silage and some barley grain with snaplage decreases the proportion of cattle with severe liver abscesses at slaughter.


Introduction
The development of low-heat unit corn varieties has created an opportunity to increase corn production for grain and silage in western Canada, with a 1.8 million metric ton increase in overall corn production and a 536 000 metric ton increase in grain production from 2012 to 2022 (Major et al. 2021;Statistics Canada n.d.).Whole-plant dry matter (DM) yield for short-season corn hybrids was shown to be greater than for whole-plant barley (Lardner et al. 2017), making corn a tempting option for silage production.Studies evaluating short-season corn silage production (Baron et al. 2006;Lardner et al. 2017;Guyader et al. 2018) as well as its use in the diets of feedlot cattle (Chibisa and Beauchemin 2018;Johnson et al. 2020) have been conducted.Johnson et al. (2020) observed increased hot carcass weight (HCW), dressing percentage (DP), and ribeye area in steers fed corn silage as a replacement for barley silage without influencing growth performance, likely due to a greater digestible energy supply for corn silage than barley silage.In contrast, other studies comparing barley silage and corn silage have re-ported no difference in dry matter intake (DMI), average daily gain (ADG), or carcass composition for finishing beef cattle (Walsh et al. 2008;Chibisa and Beauchemin 2018), suggesting that continued investigation into the replacement of barley silage with short-season corn silage in Canada is warranted.While short-season corn silage production has been investigated previously, there is little data from western Canada regarding other high-moisture corn products that are commonly utilized in more traditional corn growing areas, such as high-moisture shelled corn (HSC) or snaplage (Carey et al. 2023).
High-moisture shelled corn from short-season corn has been reported to have a greater starch concentration than dry-rolled barley grain with similar crude protein concentrations (Carey et al. 2023).While the vitreous protein matrix in corn limits starch digestion in ruminants (Owens et al. 1986), the reduction in pH during the ensiling of HSC increases starch availability (Hoffman et al. 2011) relative to dry corn.Moreover, in northern regions like Canada, corn maturity is often restricted by the length of the growing season, and the inability to reach full maturity may limit the development of the starch-protein matrix so that it is less of a barrier to starch digestion (Ahmed et al. 2014;Guyader et al. 2018).Accordingly, Carey et al. (2023) reported no difference in apparent ruminal, intestinal, or total tract starch digestibility when cattle were fed finishing diets containing HSC vs. dry-rolled barley grain.Corn grain also has a greater lipid concentration than barley grain, resulting in increased lipid intake and apparent total tract digestibility (Carey et al. 2023).Increases in dietary lipid may increase body weight (BW) gain in growing cattle and HCW through increased fat deposition and a greater energy density of the diet (Chilliard 1993).We are unaware of any studies evaluating the use of short-season HSC on feed intake, growth, and carcass characteristics of feedlot cattle in comparison to barley grain, the most commonly used cereal grain in western Canada.
Alternatively to HSC, corn may be used to produce snaplage.Snaplage consists of the grain, cob, husk, and shank, making it an energy-dense ingredient for finishing cattle (Nigon et al. 2016).Some researchers have concluded that snaplage from flint corn varieties can be used as the sole energy and roughage source in finishing diets in Brazil (Godoi et al. 2021).In a short-season corn variety, snaplage had a greater starch concentration than barley silage, while having less neutral detergent fiber (NDF) and crude protein (CP; Carey et al. 2023).Replacing barley silage and a portion of barley grain with snaplage increased ruminal starch digestibility in finishing diets equally balanced for NDF, CP, and starch concentrations (Carey et al. 2023).Increased ruminal starch digestion has been linked to improved gain:feed (G:F; Bengochea et al. 2005), but also increased risk of ruminal acidosis and liver abscesses (LAs; Nagaraja and Lechtenberg 2007).When severe, LA can decrease the value of the carcass through trim losses and condemnation of the liver (Herrick et al. 2022).
Therefore, we hypothesized that (1) completely replacing barley silage in finishing diets with short-season corn silage will have no impact on feedlot growth performance of steers but will increase carcass weight and DP; (2) replacing half of the dry-rolled barley grain (DM basis) in the diet with HSC will increase ADG of steers as well as increase HCW; and (3) the partial replacement of dry-rolled barley grain and complete replacement of barley silage with short-season snaplage will increase ADG, but HCW will decrease as more severe LA will be present at slaughter.The objectives of this study were to evaluate the complete replacement of barley silage with short-season corn silage, the partial replacement of dry-rolled barley grain with HSC, and both the partial replacement of dry-rolled barley grain and the complete replacement of barley silage with corn snaplage in finishing diets on steer performance and carcass characteristics.Fermented feed agronomics, processing, and storage Fermented feeds (barley silage, corn silage, HSC, and snaplage) were grown at the Livestock and Forage Centre of Excellence (LFCE; Clavet, SK, Canada) on non-irrigated fields with loamy, Orthic Dark Brown Chernozemic soil (Bradwell; SKSIS Working Group 2018).Barley silage and HSC were grown during the 2020 and 2021 growing seasons, while corn silage and snaplage were only grown in 2020 due to a drought in 2021.Ample corn silage and snaplage were produced in 2020 and stored in silage bags that were re-sealed at the end of the first year to be used in the second year.Information on seeding, fertilizer, herbicides, and fungicides, and harvest management for each feed by year is presented in Table 1.

Materials and methods
Barley silage was harvested at 42.3% DM in year 1 and 41.0% DM in year 2. Corn silage and snaplage were harvested at 27.0% and 69.7% DM, respectively.Silages and snaplage were chopped with a forage harvester with a theoretical chop length of 20 mm.The forage harvester was equipped with a kernel processor with a 2 mm gap.During the snaplage harvest, a snapper head was fitted to the harvester.In 2021, a silage inoculant (SiloSolve AS; Chr.Hansen Inc., Milwaukee, WI, USA) containing Enterococcus faecium DSM22502, Lactobacillus plantarum CH6072, and L. buchneri DSM22501 was applied to all chopped forages at 60,000 cfu/g of ensiled forage.Due to management needs, in 2022, the barley silage was treated with a silage inoculant containing E. faecium and L. plantarum (Sila-Bac brand 1174; Pioneer brand Seeds, Corveta Agriscience, Saskatoon, SK, Canada) at a rate of 100,000 cfu/g of ensiled forage (N.Rasmussen (personal communication, 2023)).Barley silage was packed in a horizontal concrete bunker covered with silage plastic weighted with tires.Corn silage and snaplage were packed into silage bags.Highmoisture shelled corn was harvested with a combine and ground to a processing index (PI) of 65% based on the original volume weight.The ground HSC was packed into a silage bag in year 1 and a horizontal concrete bunker covered with silage plastic and tires in year 2, as no commercial bagger was available in 2021.The targeted feed-out rate for all ensiled products was 22.9 cm/day and they were stored for at least 60 days before use.Corn silage, HSC, and snaplage were defaced using the edge of a front-end loader, and barley silage was defaced using a silage defacer (DFS121; Caterpillar Inc., Deerfield, IL, USA).

Experimental design, feedlot management, and dietary treatments
In year 1, steers received a diet containing 40% barley grain, 40% barley silage, 15% oat hulls, 3.5% canola meal, 1.2% limestone, and 0.3% mineral and vitamin supplements on a DM basis upon arrival and until the start of the study.In year 2, steers were provided a diet consisting of 49% barley grain, 22% corn silage, 16% oat thins, 7% oat hulls, 4.5% canola meal, 1.2% limestone, and 0.3% mineral and vitamin supplements on a DM basis from arrival until the start of the study.Prior to the beginning of each finishing experiment, cattle were tran- sitioned over 28 days with five dietary steps from the initial diet to a common finishing diet consisting of dry-rolled barley and barley silage (Table 2).In both years, steers were implanted with 36 mg of zeranol (Ralgro; Merck Animal Health, Rahway, NJ, USA) on arrival (69 days before trial in year 1 and 169 days before trial in year 2) and vaccinated against bovine respiratory disease (Bovashield Gold/One Shot; Zoetis, Parsippany, NJ) and clostridial diseases (Ultrabac 7/Somnubac; Zoetis, Parsippany, NJ).Steers also received a herd management tag and were treated for parasites (Solmectin Pouron; Solvet, Calgary, Alberta, Canada).In the second year, cattle received a second implant containing 100 mg of trenbolone acetate, 10 mg of estradiol, and 29 mg of tylosin (Component TE-100 with Tylan; Elanco Canada Ltd., Mississauga, ON, Canada) 99 days before the start of the finishing experiment.
At the beginning of the study in each year, all steers (n = 160; 497 ± 17.7 and 558 ± 20.1 kg BW in years 1 and   2, respectively) were given a terminal implant containing 200 mg of trenbolone acetate and 28 mg of estradiol benzoate (Synovex Plus; Zoetis Canada, Kirkland, QC, Canada) and weighed individually on two consecutive days.Steers were then blocked by BW (4 blocks; 40 steers per block) and randomized into one of 16 soil-surfaced pens (4 pens per treatment; 10 steers per pen).The average weight from the two consecutive days was considered the initial BW.Pens were equipped with a 3.3 m high, 20 cm/m porosity windbreak along the north fence, a concrete feeding bunk, and an automatic, float-activated water trough shared between two pens.Straw bedding was provided equally to all pens in the backgrounding phase but was not provided in the finishing phase.Bedding packs were removed in June, when pens were cleaned.Steers were assessed daily for clinical signs of illness by trained staff, and, when appropriate, veterinary intervention was applied as per the standard operating procedures of the feedyard.In year 1, three steers were found dead in  ) with water as a carrier.Water weight was used in DM calculations, and DM inclusion of urea, salt, and supplements was considered consistent with the formulated diet.
c Dietary DM and nutrient composition were mathematically reconstituted from the formulated ingredient inclusion and the ingredient composition shown in Table 3. Limestone, salt, urea, and supplements were not analyzed for nutrient composition.Limestone, salt, urea, and supplements DM were estimated at 99%.Limestone was estimated to contain 34.00% Ca, and urea was estimated to contain 281.0%CP.Dried ingredient samples were composited by ingredient in the first year (n = 1) and over 3 or 4 weeks to yield three samples per ingredient in the second year (n = 3).d Roughage physically effective fiber (peNDF) was calculated as the concentration of neutral detergent fiber in the roughage multiplied by the proportion of material greater than 4 mm (Gentry et al. 2016) and was only measured in year 2. e Calculations for net energy of maintenance (NE m ) and gain (NE g ) are described by NRC (2001).
the pen (two on SNAP by strangulation and one on BGBS by bloat), and one steer on HCBS was removed from the study after three treatments for bloat.There were no deaths or removals in 2022.
In both years, all diets were formulated to meet or exceed the protein, mineral, and vitamin requirements of finishing steers with an initial BW of 435 kg, a a final BW of 650 kg, an ADG of 1.90 kg, and targeting 27% of empty body fat (NASEM 2016).Diets included limestone, which was top-dressed by hand to the forage component of the diet, and urea, which was added using the Micro Weigh System (Micro Technologies Feedlot Solutions, United Farmers of Alberta Co-operative Ltd., Calgary, AB, Canada).Salt, microminerals (Shelter Valley Beef Micro Premix; ADM Animal Nutrition, Lethbridge, AB, Canada), vitamins A, D, and E, and monensin (final concentration of 33 mg/kg of DM; Rumensin Premix, Elanco Animal Health) were also added to each diet by the Micro Weigh Sys-tem.Ractopamine hydrochloride (30 mg/kg of DM; Optaflexx 100 Premix, Elanco Animal Health) was included in the diet during the last 28 days before slaughter.In addition to the common ingredients listed above, the control (BGBS) consisted of dry-rolled barley grain (88.0% of DM) processed to a 65% PI and barley silage (9.7% of DM in year 1 and 10.1% of DM in year 2).For the corn silage treatment (BGCS), corn silage replaced barley silage.High-moisture shelled corn replaced 50% (DM basis) of the barley grain from BGBS (HCBS).Low HSC yields in the 2020 crop limited further replacement of barley grain with HSC.For the snaplage treatment (SNAP), snaplage replaced all the barley silage and a portion of the barley grain (11.9% of the barley grain in year 1 and 12.5% in year 2) relative to the BGBS treatment.Differences in snaplage inclusion from year to year were a result of balancing diets for NDF and starch concentrations.The original snaplage inclusion was based on the complete replacement of barley silage and balancing the BGBS and SNAP for starch concentration.Steers were fed once daily in the morning.Amounts offered were determined by feedlot staff after observing feed bunks at approximately 08:00 daily with the goal of minimizing refusals but avoid animal behavior indicative of hunger at feeding (slick bunk management).
Fermented feeds were sampled twice weekly, and barley grain was sampled once weekly.Samples were analyzed for DM by drying in a forced-air oven at 55 • C for 72 h.As-fed ingredient inclusions were adjusted when the 3-week running average of an ingredient differed by 1.0% from the value entered in the feeding software.A portion of the dried samples were ground to pass through a 1 mm sieve (Retsch ZM 200 grinder, Hann, Germany), composited by ingredient in the first year (n = 1), and over 3 or 4 weeks to yield three samples per ingredient in the second year (n = 3).Composited samples were analyzed for CP, ether extract (EE), NDF, acid detergent fiber, Ca, and P as described by Rosser et al. (2013) at Cumberland Valley Analytical Services (CVAS, Waynesboro, PA, USA; Table 2).Samples were also analyzed for starch with correction for free glucose (Hall 2009) and for ash (AOAC 2000), with the latter using 1.5 g of initial sample weight, combusted for 4 h at 550 • C, and residues were weighed before cooling by CVAS.Organic matter (OM) was considered to be 100% ash (% of DM).Net energy for maintenance (NE m ) and gain (NE g ) were calculated using NRC equations ( 2001).
In the second year, fresh samples of silages and snaplage were also analyzed twice weekly for particle size using the Penn State Particle Separator using 19, 8, and 4 mm screens above the pan (Gentry et al. 2016;Heinrichs and Jones 2016).The proportion of material left on the screens multiplied by the NDF concentration of the silage or snaplage was considered as the physically effective fiber (peNDF).Barley grain and HSC were not used in the peNDF calculations as the particle sizes of these ingredients were generally less than 4 mm (Heinrichs and Jones 2016).Therefore, peNDF reported in the diets only considers the forage in the diet.Daily diet ingredient inclusions were measured on an as-fed basis based on the weights loaded into a horizontal mixer (Knight RC 260 V feed mixer; Kuhn North America, Inc., Brodhead, WI, USA) mounted on a 2017 Frieghtliner 114SD truck (Daimler Truck North America, LLC, Portland, OR, USA) using batch tracking and bunk management software (Read-N-Feed; Micro Technologies Feedlot Solutions, United Farmers of Alberta Co-operative Ltd., Calgary, AB, Canada).Amounts of feed delivered were converted to a DM basis using the weekly DM concentration of the ingredients.To obtain the nutrient concentrations of the diets, the daily percentage of the ingredient in the diet (DM basis) was multiplied by the nutrient concentration, and the nutrient contributions from the ingredients were summed (daily batch nutrient concentration).The average and standard deviation for the chemical composition of the feed ingredients used over the 2 years are reported in Table 3.

Performance characteristics
Daily feed delivery to each bunk was recorded using the feeding management software.Bunks were manually emptied weekly, with refusals, if any, weighed and sampled for measurement of DM concentration.The average difference in weight between the total DM offered weekly and the amount refused after 7 days was used to determine pen DMI.Steers were weighed every 28 days after the start of the trial to monitor growth.Before slaughter, cattle were weighed on two consecutive days, and the average of the two BW values was considered the individual final BW.A 4.0% shrink was applied to the final BW to determine the final shrunk BW (NASEM 2016).The ADG was determined by subtracting the initial BW from the final shrunk BW and dividing by the number of days on trial.The G:F was calculated as ADG divided by DMI.Carcass-adjusted final BW was determined by dividing HCW at slaughter by the average DP of all steers (59.3%; de Melo et al. 2019).Carcass-adjusted ADG and G:F were calculated in the same manner described above, substituting final shrunk BW for carcass-adjusted final BW.All individual data from the three deceased steers as well as the one removed steer described above were excluded from analysis, and pen-level data were adjusted for the number of days the steers were in each pen.

Fecal starch concentrations
As an indicator of starch utilization, fresh fecal samples were collected from each pen on day 28 of the study in both years, 15 days before slaughter in year 1, and 10 days before slaughter in year 2 for starch concentration analysis.Four subsamples (minimum 150 g each) were collected within 4 h of feeding from the floor of each pen according to the methods of Jancewicz et al. (2017).Feces were immediately composited by pen on an equal weight basis, dried in a forcedair oven at 55 • C for 120 h, and ground through a 1 mm screen (Retsch ZM 200 grinder).Fecal samples were analyzed for starch concentration by CVAS using the same method as starch analysis for feed ingredient samples.

Carcass characteristics
After 99 days (year 1) or 72 days (year 2) on trial, steers were transported 660 km to a commercial abattoir (Cargill Meat Solutions, High River, AB, Canada) and held overnight in common pens with access to water but not fed prior to slaughter the next morning.At slaughter, trained personnel from the University of Saskatchewan (Saskatoon, SK, Canada) were present to monitor the sequence of slaughter and evaluate livers for abscess abnormalities modified from the methods of Brown and Lawrence (2010).Briefly, livers were considered "normal" if no scars or LA were present, "A−" if one or two small LA (≤1.8 cm) or inactive scars were present, "A" if two to four small LA were present, and "A+" (severe) if there were more than four small LA or one or more large (>1.8 cm) active LA present.The data are presented as total LA and severe LA percentages.The abattoir provided individual HCW (kidney, pelvic, and heart fat removed), which was used to calculate DP by dividing HCW by the final shrunk BW.After 24 h of cooling, carcasses were assessed for yield and quality by a certified grader (Canadian Beef Grading Agency, Calgary, AB, Canada), and backfat thickness, ribeye area, and marbling scores between the 12th and 13th ribs were measured by a computer vision grading system (VBG 2000 e + v Technology Table 3. Analyzed dry matter (DM) and nutrient concentrations of barley grain, barley silage, short-season corn silage, shortseason high-moisture shelled corn, and short-season snaplage included in diets fed to finishing steers.a Corn silage and snaplage were the same crop used over 2 years.Barley silage, corn silage, and snaplage were inoculated with a silage inoculant in year 1 (SiloSolve AS; Chr.Hansen Inc., Milwaukee, WI, USA) after chopping with a forage harvester equipped with a kernel processor with a 2 mm gap.Barley silage was inoculated with Sila-Bac brand 1174 (Pioneer brand Seeds; Corveta Agriscience, Saskatoon, SK, Canada) in year 2. High-moisture shelled corn was harvested with a combine and ground to a 65% processing index.Corn silage, snaplage, and high-moisture shelled corn were packed in silage bags.Barley silage was packed in a horizontal concrete bunker covered with silage plastic and weighted with tires.
b Dry matter was calculated on a weekly basis and contributes to the average and standard deviation.c Roughage physically effective fiber (peNDF) was calculated on a weekly basis as the concentration of neutral detergent fiber in the roughage multiplied by the percentage of roughage material greater than 4 mm (Gentry et al. 2016) and only measured in year 2. d Calculations for net energy for maintenance (NE m ) and gain (NE g ) are described by NRC ( 2001).

Statistical analysis
All statistical analyses were conducted using SAS (SAS version 9.4; SAS Institute, Cary, NC, USA).Normally distributed, continuous data (BW, ADG, fecal starch concentrations, HCW, DP, ribeye area, and back-fat thickness) were analyzed using the MIXED procedure of SAS.The experiment was treated as a randomized complete block design, where the pen was considered the experimental unit (n = 8/treatment, 4/treatment/year).For growth performance and fecal starch concentration data, pen means were calculated before analysis, and the model included the fixed effect of treatment with year and BW block as random effects.For individual carcass data, pen, year, and BW block were considered random effects in the model.Treatment means for these variables and the standard error of the means (SEM) were determined using the LSMEANS option.Normality was confirmed using the Shapiro-Wilk test.The GLIMMIX procedure of SAS was used to analyze DMI, G:F, and marbling scores as they did not meet the normal distribution criterion of the MIXED procedure.Categorical data (quality grades, yield grades, and LA) were analyzed as a series of binomial distributions using the GLIMMIX procedure of SAS.Treatment means and SEM were calculated using the ILINK option.Denominator degrees of freedom for all variables were calculated using the Satterthwaite approximation.Contrasts were used to compare SNAP, HCBS, and BGCS to the BGBS treatment for all vari- a Treatment diets consisted of finishing diets with dry-rolled barley grain and barley silage (BGBS), dry-rolled barley grain and corn silage (BGCS), dry-rolled barley grain, high-moisture shelled corn, and barley silage (HCBS), and dry-rolled barley grain and snaplage (SNAP).The BGBS diet contained dry-rolled barley grain (88.0% in both years), barley silage (9.7% and 10.1% in years 1 and 2), limestone (1.5% in both years), urea (0.59% and 0.20% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The BGCS diet contained dry-rolled barley grain (88% in both years), corn silage (9.6% and 9.8% in years 1 and 2), limestone (1.5% in both years), urea (0.73% and 0.45% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The HCBS diet contained dry-rolled barley grain (44.0% in both years), barley silage (9.8 and 10.0% in years 1 and 2), high-moisture shelled corn (44.0% in both years), limestone (1.5% in both years), urea (0.46% and 0.27% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The SNAP diet contained dry-rolled barley grain (77.5% and 77.0% in years 1 and 2), snaplage (20.0% and 20.7% in years 1 and 2), limestone (1.5% in both years), urea (0.79 and 0.55% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).b Probability that the BGBS is not different from BGCS, HCBS, or SNAP using the CONTRAST option in SAS (version 9.4).c A 4.0% shrink (NASEM 2016) was applied to the final BW and used to calculate shrunk live ADG and G:F.d Hot carcass weight was divided by the study average dressing percentage of 59.3% and used as the final BW to calculate ADG and G:F. e Fresh fecal samples were collected from the pen floor on day 28 of the trial in both years, then 15 days before slaughter in year 1 and 10 days before slaughter in year 2.
ables and were presented along with treatment means and the largest SEM.Differences between means were considered significant when P ≤ 0.05, and tendencies were considered when 0.05 < P ≤ 0.10.

Results
DMI for steers consuming diets that contained corn was not different (P ≥ 0.21; Table 4) than those consuming BGBS.By study design, the initial BW of steers receiving BGCS, HCBS, or SNAP did not differ (P ≥ 0.51) from that of those receiving BGBS.Shrunk final BW, ADG, and G:F did not differ (P ≥ 0.21) between BGCS, HCBS, or SNAP and BGBS.Steers fed BGCS did not differ (P ≥ 0.23) from BGBS in carcass-adjusted final BW or ADG.Carcass-adjusted final BW and ADG were greater (P ≤ 0.02) for steers fed HCBS than BGBS.Steers fed SNAP tended to have greater (P = 0.06) carcass-adjusted final BW and ADG relative to BGBS.Carcass-adjusted G:F was not different (P ≥ 0.17) for BGCS, HCBS, or SNAP compared to BGBS.Fecal starch concentrations were greater (P = 0.02) for HCBS than BGBS, but BGCS and SNAP did not differ (P ≥ 0.77) from BGBS.
HCW and DP were greater (P ≤ 0.05, Table 5) for steers consuming HCBS over BGBS, but those consuming BGCS and SNAP did not differ (P ≥ 0.16) from BGBS.Yield grades, quality grades, marbling scores, ribeye area, and backfat thickness were not affected (P ≥ 0.13) by diet.While total LAs did not differ (P ≥ 0.45), cattle fed SNAP had fewer (P = 0.02) severe LAs than those consuming BGBS.

Discussion
Short-season high-moisture corn products used in this study had greater CP and NDF concentrations and less starch concentration than those grown in the USA and eastern Canada (NASEM 2016).Short-season corn hybrids grown in western Canada are mostly flint varieties as opposed to the dent varieties commonly grown in eastern Canada and the USA (Kereliuk and Sosulski 1996).Grain from flint varieties has a larger germ and thicker bran layer than dent varieties, which may account for greater CP and NDF concentrations (Kereliuk and Sosulski 1996) and, therefore, decreased starch concentration.Additionally, the shorter growing season in western Canada may limit starch deposition, also contributing to decreased starch concentration compared to eastern Canada and the USA (Environment and Climate Change Canada 2022).The short-season products in this study were also grown without the aid of irrigation.This would be typical in western Canada, as irrigated fields only accounted for 1.5% of all seeded land in 2021 (Statistics Canada 2021, n.d.).As a result, the HSC from year 2 was grown under severe drought conditions when precipitation was 47.4 mm less than the 2014-2019 historical average (Environment and Climate Change Canada 2022).When corn is drought-stressed, smaller ears are produced with less grain fill, resulting in decreased starch content (Weisany et al. 2021).The drought conditions experienced in this study may help explain the lesser starch concentration found in the HSC used in year 2 compared with other short-season, high-moisture corn products a Treatment diets consisted of finishing diets with dry-rolled barley grain and barley silage (BGBS), dry-rolled barley grain and corn silage (BGCS), dry-rolled barley grain, high-moisture shelled corn, and barley silage (HCBS), and dry-rolled barley grain and snaplage (SNAP).The BGBS diet contained dry-rolled barley grain (88.0% in both years), barley silage (9.7% and 10.1% in years 1 and 2), limestone (1.5% in both years), urea (0.59% and 0.20% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The BGCS diet contained dry-rolled barley grain (88% in both years), corn silage (9.6 and 9.8% in years 1 and 2), limestone (1.5% in both years), urea (0.73% and 0.45% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The HCBS diet contained dry-rolled barley grain (44.0% in both years), barley silage (9.8% and 10.0% in years 1 and 2), high-moisture shelled corn (44.0% in both years), limestone (1.5% in both years), urea (0.46% and 0.27% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).The SNAP diet contained dry-rolled barley grain (77.5% and 77.0% in years 1 and 2), snaplage (20.0% and 20.7% in years 1 and 2), limestone (1.5% in both years), urea (0.79% and 0.55% in years 1 and 2), salt (0.2% in both years), and a mineral and vitamin supplement (0.025% in both years).b Probability that the BGBS is not different from BGCS, HCBS, or SNAP using the CONTRAST option in SAS (version 9.4).c CBGA yield grade 5 was not assigned to any carcass.d Canadian Beef Grading Agency (CBGA) quality grade A was not assigned to any carcass.Other includes carcasses with CBGA grades B1 (backfat thickness less than 2 mm) and B4 (dark cutter).e United States Department of Agriculture marbling scores: 100 = practically devoid, 200 = traces, 300 = slight, 400 = small, 500 = modest, 600 = moderate, 700 = slightly abundant, 800 = moderately abundant, and 900 = abundant.f Severe = one or more large (>1.8 cm) or more than four small (≤1.8 cm) abscesses (Brown and Lawrence 2010).

Replacing barley silage with corn silage
Results from this study confirmed our hypothesis that replacing barley silage with corn silage would not impact the growth performance or carcass characteristics of finishing feedlot cattle.The use of corn silage instead of barley silage has produced mixed results concerning HCW and DP (Walsh et al. 2008;Chibisa and Beauchemin 2018;Johnson et al. 2020) and may reflect differences in the composition of the barley and corn silage used in these studies.For example, Walsh et al. (2008) used corn silage that was similar in starch concentration to barley silage and found no differences in carcass traits, while Johnson et al. (2020) replaced barley silage with corn silage that was approximately 7.5% higher in starch concentration.The higher level of starch most likely contributed to the increased HCW and DP for cattle fed corn silage in their study, while the similar calculated starch intake as well as measured fecal starch concentration between corn silage and barley silage in our study did not produce differences in HCW or DP.Regardless, the current data support the notion that complete replacement of barley silage with short-season corn silage (DM basis) in finishing rations is not detrimental to cattle performance (Chibisa and Beauchemin 2018;Johnson et al. 2020).

Replacing barley grain with high-moisture shelled corn
While the use of HSC did not affect shrunk live ADG when it replaced half of the dry-rolled barley grain in HBCS diets, steers fed HBCS did have greater HCW and DP when compared to BGBS.As such, the improvements in DP led to an increased carcass-adjusted final BW.As differences in DMI were not apparent in the current study, but NE m and NE g concentrations were numerically greater for HCBS than BGBS, greater energy intake with a greater starch concentration in HSC relative to barley grain for HBCS-fed steers is most likely the cause of the greater HCW and DP as stated above (NASEM 2016).
In a recent study comparing barley grain to HSC in finishing diets, Carey et al. (2023) reported similar total tract starch digestibility, but in the current study, steers fed HCBS had greater fecal starch concentrations than those fed BGBS.Fermentation of HSC during storage encourages the degradation of linkages in the zein-starch matrix (Hoffman et al. 2011;Duvnjak et al. 2022).When opening the storage bag in year 1, HSC pH was 5.04, and when opening the bunker in 2022, HSC pH was 4.72.This is greater than the recommended pH of 4.0-4.5 for HSC, indicating that conditions during ensiling may have been inadequate (Seglar and Shaver 2014).Therefore, storage conditions and ruminal starch degradation rates of HSC could be an area of future study.In addition, future research is needed to evaluate optimal replacement rates of barley grain by HSC in feedlot diets when replacing barley grain.The current study indicates that 50% replacement of dry-rolled barley grain with HSC does not impact the live performance of finishing steers but may increase HCW and DP.
Replacing barley silage and barley grain with snaplage Partial replacement of barley grain and the complete replacement of barley silage with snaplage did not increase shrunk live ADG and the proportion of steers with severe LA or decreased HCW as hypothesized.In fact, the proportion of steers with severe LA decreased with no effect on HCW or live performance for cattle fed SNAP over BGBS.The hypothesis developed for this study was based on lower minimal ruminal pH and increased ruminal starch digestibility reported with similar experimental diets (Carey et al. 2023).The snaplage used by Carey et al. (2023) contained approximately 10%-15% less DM, and the starch concentration was about 12%-15% greater than the snaplage used in this study.The differences in chemical composition between that in Carey et al. (2023) and the present study highlight variability in snaplage composition, even from the same hybrid variety grown in the same area but in different years and environmental conditions (Guyader et al. 2018).Second, the lesser starch concentration (Bryant and Jennings 2022) in the snaplage used in this study may have limited the risk of ruminal acidosis (Bengochea et al. 2005) and therefore the risk of severe LA.
Another potential reason for the reduced severity of LA in this study may be due to a greater peNDF concentration for SNAP than BGBS-fed steers, although this was only measured in the second year of the study.Researchers have suggested that roughage level is an important factor in deterring LA in feedlot cattle (Reinhardt and Hubbert 2015), and more recent studies have suggested that both the particle size of the forage (Llonch et al. 2020;Lockard et al. 2021;Pereira et al. 2023) and the indigestibility of the forage may contribute to the regulation of ruminal fermentation (Pereira et al. 2023).Research conducted investigating high and low levels of peNDF in barley-based diets concluded that increasing peNDF results in greater DP, marbling scores, and AAA quality grades and tends to reduce severe LA rates without affecting live performance (Pereira et al. 2021).In another study, it was reported that increasing peNDF in barley-based diets increased meal frequency, slowed eating rates, stimulated ruminal motility, increased mean pH, reduced permeability of the gastrointestinal tract, and were indicators of systemic inflammation (Pereira et al. 2023).While not the focus, the current study supports the concept that increasing peNDF in finishing diets may help reduce the severity of LA.
Carcass-adjusted final BW and ADG tended to be increased when snaplage substituted barley silage and a portion of the barley grain in the finishing diets, most likely because steers fed snaplage had a numerically greater HCW and DP than the study average of 59.3%.Therefore, the additive effect of numerically greater HCW and DP likely led to tendencies for carcass-adjusted final BW and ADG.These results demonstrate that snaplage can replace barley silage and some barley grain in western Canadian beef finishing diets with tendencies toward greater carcass-adjusted final BW and ADG, but nutritional evaluation of snaplage for starch concentration and peNDF is advised.
As indicated in the comparisons of snaplage and HSC in this study and Carey et al. (2023), growing conditions have a major impact on the composition and value of high-moisture corn products as well as their associated outcomes when fed to cattle.Under the conditions of the present study, there were no adverse effects of replacing barley silage with corn silage, replacing 50% of the barley grain with high-moisture shelled corn, or replacing barley silage and part of the barley grain with snaplage.

Table 2 .
Diet composition and nutrient concentrations of formulated treatment diets fed to finishing steers a .
All experimental procedures followed the Canadian Council of Animal Care (2009) guidelines and were approved by the University of Saskatchewan Animal Research Ethics Board (protocol No. 20200085).

Table 1 .
Agronomics of fermented feeds fed to finishing steers over two consecutive years.

Table 4 .
Performance parameters and fecal starch concentrations of steers fed finishing diets in which barley products were substituted with high-moisture corn products.
Note: SEM, standard error of the means.

Table 5 .
Carcass characteristics of steers fed finishing diets in which barley products were substituted with high-moisture corn products.
Note: SEM, standard error of the means.