Effect of Supplemental Calcium Levels on Feedlot Growth Performance and Dietary Net Energy Utilization during the Receiving Feeding Period of Calf-Fed Holstein Steers

Abstract Yearling beef steers (n = 238; initial BW=402 ± 31.2 kg) were used to evaluate a Bacillus subtilis probiotic on growth performance, dietary net energy (NE) utilization, carcass characteristics, and fecal and subiliac lymph node Salmonella prevalence during a 140-d finishing period. Steers were allotted to 24 pens (n = 9 to 10 steers/pen) and assigned to one of two treatments (12 pens/treatment): no probiotic (CON) or 0.50 g·steer-1·d-1 of a Bacillus subtilis PB6 probiotic (CLOSTAT® 500, Kemin Industries, Des Moines, IA; CLO). Steers were transitioned to a 90% concentrate diet (DM basis) over 14-d. Steers were fed once daily at 0700 h; bunks were managed according to a slick bunk management. Fecal samples were collected on d 1, 28, 56, 112, and 140 from each pen (n = 5 steers/pen) via rectal palpation and composited by pen for determination of Salmonella prevalence. Upon harvest, subiliac lymph nodes were obtained from 60 steers in CON and 57 steers in CLO. Data were analyzed as a randomized complete block design; pen was the experimental unit; α of 0.05 determined significance. No differences were detected (P ≥ 0.25) between treatments for live or carcass-adjusted average daily gain, dry matter intake, gain efficiency, dietary NE utilization, nor calculated dietary NE content based upon performance. No differences were detected between treatments for any carcass traits (P ≥ 0.15). Salmonella was not recovered in any fecal samples except on d 112, where steers from CLO had a numerically lower (P = 0.17; 8.3 vs. 25.0%) incidence of fecal Salmonella compared to CON and on d 140 fecal, where Salmonella incidence did not differ (P = 0.34; 0.0 vs. 8.3%) for CON and CLO, respectively. Salmonella was not recovered in any subiliac lymph nodes. These data indicate that CLO did not influence growth performance or Salmonella prevalence.

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PSX-B-5 Effect of replacement of dry-rolled corn with un-processed rye on growth performance, efficiency of dietary net energy utilization, and carcass traits of finishing heifers

Journal of Animal Science ◽

10.1093/jas/skab235.813 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 458-459

Author(s):

Keith M Buckhaus ◽

Warren C Rusche ◽

Zachary K Smith

Keyword(s):

Body Weight ◽

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Estradiol Benzoate ◽

Energy Utilization ◽

Net Energy ◽

Final Body Weight ◽

Trenbolone Acetate ◽

Finishing Diets

Abstract Continental × British beef heifers were used in a randomized complete block design experiment to evaluate the effects of replacing dry-rolled corn with unprocessed rye on growth performance, efficiency of dietary net energy (NE) utilization, and carcass trait responses in finishing heifers. Heifers (n = 56; 433 ± 34.0 kg) were transported 241 km from a regional sale barn to the Ruminant Nutrition Center in Brookings, SD. Heifers were blocked by weight grouping and then allotted to pens (n = 7 heifers/pen and 4 pens/treatment). Treatments included a finishing diet that contained 60% grain (DM basis) as dry-rolled corn (DRC) or unprocessed rye grain (RYE). On d 14, heifers were consuming the final diet and were implanted with 200 mg of trenbolone acetate and 28 mg of estradiol benzoate (Synovex-Plus, Zoetis, Parsippany, NJ). RYE heifers had decreased (P ≤ 0.01) final body weight, average daily gain, and gain efficiency; but tended (P = 0.08) to have a greater dry matter intake compared to DRC. RYE had decreased (P ≤ 0.01) observed dietary NE and decreased (P ≤ 0.01) observed-to-expected dietary NE ratio for maintenance and gain compared to DRC. Dressing percentage, 12th rib fat thickness, ribeye area, and the distribution of USDA yield and quality grades were not altered (P ≥ 0.12) by diet. Hot carcass weight, yield grade, estimated empty body fat (EBF), and body weight at 28% EBF decreased (P ≤ 0.02) and retail yield increased (P= 0.01) in RYE compared to DRC. These data indicate that unprocessed rye is a palatable feed ingredient for inclusion in finishing diets for beef cattle and that rye inclusion only minimally influences carcass quality. The feeding value of unprocessed rye is considerably less (21.4%) than that of dry-rolled corn using current standards and approximately 91% of the NE value of processed rye.

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Evaluation of hybrid rye on growth performance, carcass traits, and efficiency of net energy utilization in finishing steers

Translational Animal Science ◽

10.1093/tas/txaa173 ◽

2020 ◽

Vol 4 (3) ◽

Author(s):

Warren C Rusche ◽

Julie Ann Walker ◽

Peter Sexton ◽

Rebecca S Brattain ◽

Zachary K Smith

Keyword(s):

Growth Performance ◽

Average Daily Gain ◽

Carcass Traits ◽

Energy Utilization ◽

Carcass Weight ◽

Experimental Unit ◽

Net Energy ◽

Complete Replacement ◽

Finishing Steers ◽

Hybrid Rye

Abstract Crossbred beef steers with a high percentage of Angus ancestry [n = 240, initial shrunk body weight (BW), 404 ± 18.5 kg] were used in a 117-d feedlot experiment to evaluate the effect of hybrid rye (Rye; KWS Cereals USA, LLC, Champaign, IL) as a replacement for dry-rolled corn (DRC) on growth performance, carcass traits, and comparative net energy (NE) value in diets fed to finishing steers. Rye from a single hybrid (KWS Bono) with an ergot alkaloid concentration of 392 ppb was processed with a roller mill to a processing index (PI) of 78.8 ± 2.29. Four treatments were used in a completely randomized design (n = 6 pens/treatment; 10 steers/pen), where DRC (PI = 86.9 ± 4.19) was replaced by varying proportions of Rye [DRC:Rye, dry matter (DM) basis (60:0), (40:20), (20:40), and (0:60)]. Liver abscess scores and carcass characteristics were collected at the abattoir. Carcass-adjusted performance was calculated from hot carcass weight (HCW)/0.625. Performance-adjusted NE was calculated using carcass-adjusted average daily gain (ADG), DM intake (DMI), and mean equivalent shrunk BW with the comparative NE values for rye calculated using the replacement technique. Data were analyzed using the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC) with pen as the experimental unit. Treatment effects were tested using linear and quadratic contrasts, as well as between diets with and without Rye. Replacing DRC with Rye linearly decreased (P ≤ 0.01) carcass-adjusted final BW, ADG, DMI, and gain:feed (G:F). Feeding rye linearly decreased HCW and longissimus muscle area (P ≤ 0.04). Distributions of liver scores and USDA grades for quality and yield were unaffected by treatment (P ≥ 0.09). Estimated replacement NE for maintenance (NEm) and gain (NEg) values for rye, when included at 60% of diet DM, were 1.90 and 1.25 Mcal/kg, respectively. Rye can be a suitable feed ingredient in finishing diets for feedlot steers. Estimated replacement values of Rye when fed at 60% of diet DM closely agreed with current tabular standards but, when included at 20% of diet DM, estimated NEm and NEg values of Rye were increased 9.5% and 12.8%, respectively. Net energy value of Rye for gain is approximately 84% compared to DRC; thus, the complete replacement of DRC with Rye depressed DMI, ADG, G:F, and carcass weight.

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Evaluation of an active live yeast (Levucell Saccharomyces cerevisiae, CNCM l-1077) on receiving and backgrounding period growth performance and efficiency of dietary net energy utilization in low health risk beef steers1

Translational Animal Science ◽

10.1093/tas/txaa127 ◽

2020 ◽

Vol 4 (3) ◽

Author(s):

Zachary K Smith ◽

Kip Karges ◽

Angel Aguilar

Keyword(s):

Health Risk ◽

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Energy Utilization ◽

Feed Ratio ◽

Experimental Unit ◽

Net Energy ◽

Respiratory Pathogens ◽

Live Yeast

Abstract The objective of this experiment was to evaluate the influence of an active live yeast direct-fed microbial (DFM) product on receiving and backgrounding period growth performance and efficiency of dietary net energy (NE) utilization in low health risk beef steers. Maine-Anjou × Angus steers (n = 199; body weight [BW] = 252 ± 32.1 kg) were received from two sources at the Ruminant Nutrition Center in Brookings, SD, in November 2019 and used in a 77-d feedlot receiving and backgrounding experiment. Steers were provided access to long-stem hay and ad libitum water upon arrival. Steers were weighed, vaccinated for respiratory pathogens (source 2 only): infectious bovine rhinotracheitis, bovine viral diarrhea types 1 and 2, parainfluenza-3 virus, and bovine respiratory syncytial virus (Bovi-Shield Gold 5, Zoetis, Parsippany, NJ) vaccinated for clostridial species (Ultrabac 7/Somubac, Zoetis) and pour-on moxidectin (Cydectin, Bayer, Shawnee Mission, KS). Steers (n = 176 steers; initial unshrunk BW = 235 ± 27.6 kg) were allotted to pens (n = 20 pens; 10 pens per treatment; eight or nine steers per pen). Diets were based upon corn silage, dry-rolled corn, and dried distillers grains; dietary treatments were 1) no DFM (CON) and 2) DFM (Levucell SC, Advantage Titan, CNCM l-1077), fed at 10 g/steer/d providing 8 × 109 CFU of active live yeast to each steer daily (DFM). Initial BW was the average of day −1 and day 1 BW (n = 176 steers; initial BW = 253 ± 27.6 kg). On day 21, steers received a 200-mg progesterone and 20-mg estradiol benzoate implant. Data were analyzed from day 1 to 47 (receiving period), day 48 to 77, and from day 1 to 77 as a randomized complete block design; pen served as the experimental unit for all analyses. On day 47 of the experiment, DFM had greater BW (P = 0.01) by 0.9% and average daily gain (ADG; P = 0.01) by 4.2% and gain-to-feed ratio (G:F) tended (P = 0.13) to be 2.8% greater. Day 77 BW did not differ (P = 0.60), cumulative (days 1–77): ADG (P = 0.47), dry matter intake (P = 0.66), and G:F (P = 0.56) were similar. Yeast inclusion had no appreciable influence on performance-based dietary NE utilization or the ratio of observed/expected dietary NE (P ≥ 0.59). In low health risk steers, DFM improved performance during the feedlot receiving period. However, no improvements for DFM were detected for cumulative performance from day 1 to 77. The confirmation of yeast counts indicated the CFU to be above the expected level at the start of the trial but was found below expected level at the end of the trial. This may explain differences during the initial 47 d compared to cumulative growth performance results.

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PSX-36 Effect of forage neutral digestion fiber level for feedlot lambs: growth performance

Journal of Animal Science ◽

10.1093/jas/skz258.888 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 451-451

Author(s):

Josue Godinez ◽

Alejandro Plascencia ◽

Francisco Castrejón-Pineda ◽

Juan Carlos Ramírez-Orejel ◽

Luis Corona

Keyword(s):

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Neutral Detergent Fiber ◽

Energy Utilization ◽

Net Energy ◽

Finishing Diets ◽

Feedlot Lambs ◽

Sheep Production ◽

Daily Gain

Abstract The main objective of sheep production in Mexico is the production of meat. The greater demand of sheep meat in relation to the offer generated an attractive market that favored the intensification of the fattening, to take advantage of the growth of lambs in its different stages, and reduce the days of fattening. Thirty-two lambs (28.50± 2.67 kg initial shrunk weight) were used in a 63-day feeding trial (4 pens per treatment, randomized complete block design) to evaluate neutral detergent fiber level (4, 8, 12, and 16% diet DM) on finishing-phase growth performance, dietary energetics and carcass traits. Dietary treatments consisted of a cracked corn-based diet in which the NDF concentration of diet was manipulated by replacing cracked corn grain by corn stubble. Dietary NDF level showed a quadratic response on average daily gain and gain efficiency, being those maximal at 8% NDF level. Lambs fed 8% NDF level tended (P = 0.07) to shown greater dry matter intake than others treatments. The ratio of observed-to-expected dietary net energy was 3% lower (0.97) for lambs fed 4% NDF, while the ratio of observed-to-expected dietary net energy for lambs that were fed with 8, 16 and 16% NDF were closely to 1.00. Hot carcass weight (HCW) and dressing percentage (DP) were maximal for the lambs fed 8% NDF level (quadratic effect, P ≤ 0.03); beyond this level, HCW and DP percentage decreased as NDF level increased. Using corn stubble as source of NDF in growing-finishing diets for lambs, the optimal NDF level was 8%. Fiber level below 8% decreases net energy utilization, and this may be cause by digestive disorders. Fiber levels upper 8% did not affect energy utilization; however, affect negatively average daily gain, feed efficiency and carcass characteristics by effect of high levels of fiber on energy dilution of diet.

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Increasing hay inclusion in silage-based receiving diets and its effects on performance and energy utilization in newly weaned beef steers

Translational Animal Science ◽

10.1093/tas/txaa026 ◽

2020 ◽

Vol 4 (2) ◽

pp. 848-853

Author(s):

Dathan T Smerchek ◽

Elizabeth M Buckhaus ◽

Katie D Miller ◽

Zachary K Smith

Keyword(s):

Growth Performance ◽

Block Design ◽

Corn Silage ◽

Energy Utilization ◽

Experimental Unit ◽

Net Energy ◽

Beef Steers ◽

Linear Effect ◽

Randomized Complete Block Design ◽

Red Angus

Abstract The influence of grass hay (GH) inclusion in replacement of corn silage in receiving diets on growth performance and dietary net energy (NE) utilization was evaluated in newly weaned beef steers (n = 162 Charolais-Red Angus cross steers; initial body weight [BW] = 278 ± 13.4 kg). Treatments were (DM basis): 1) 0% GH, 2) 10% GH, or 3) 20% GH inclusion in replacement of corn silage in receiving diets fed to newly weaned beef steers for 56 d. The study was conducted from October to December of 2019. Data were analyzed as randomized complete block design with pen serving as the experimental unit for all analyses. Increasing dietary inclusion of hay had no influence (P ≥ 0.11) on final BW, ADG, gain:feed or observed/expected dietary NEM and NEG, observed/expected dry matter intake (DMI), or observed/expected ADG. GH inclusion increased (linear effect, P = 0.01) DMI. Observed DMI for all treatments was approximately 15% to 17% less than anticipated based upon steer growth performance and tabular NE values. Evaluation of observed/expected ADG was 31% to 37% greater than expected for the steers in the present study. Particles less than 4 mm increased (linear effect, P = 0.01) and greater than 4 mm decreased (linear effect, P = 0.01) as GH replaced corn silage in the receiving diet. As the proportion of particles greater than 4 mm increased, cumulative ADG was decreased. These data indicate that GH should be considered in corn silage-based receiving diets to improve DMI. In high-risk calves, improved DMI could result in a lesser incidence of morbidity, although no morbidity was observed in any steers from the present study.

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116 Effect of Coated and Non-coated Steroidal Implants on Growth Performance, Dietary Net Energy Utilization and Carcass Traits of Feedlot Finishing Steers

Journal of Animal Science ◽

10.1093/jas/skab054.064 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 36-37

Author(s):

Elizabeth M Buckhaus ◽

Zachary K Smith

Keyword(s):

Growth Performance ◽

Carcass Traits ◽

Estradiol Benzoate ◽

Corn Silage ◽

Energy Utilization ◽

Carcass Weight ◽

Net Energy ◽

Trenbolone Acetate ◽

Coated Implant ◽

Dietary Treatments

Abstract Maine-Anjou x Angus steers (n = 156, initial BW 366 ± 37.2 kg) were used in a 132-d finishing experiment at the Ruminant Nutrition Center in Brookings, SD. Steers were weighed on two consecutive days and assigned into 5 weight blocks. Within each weight block steers were randomly assigned to two implant types (equal steroidal hormone dose; both from Zoetis, Parsippany, NJ) and two dietary treatments in a 2 × 2 factorial arrangement. Implant treatments consisted of 1) Coated implant, 200 mg trenbolone acetate (TBA), 28 mg estradiol benzoate (EB) (Synovex ONE Feedlot, ONE) or 2) Non-coated implant, 200 mg TBA, 28 mg EB (Synovex PLUS; PLUS), placed in the left ear. Dietary treatments were 1) 15% or 2) 30% corn silage (DM basis). No interaction between implant and corn silage inclusion was observed for carcass-adjusted (hot carcass weight / 0.63) growth performance, dietary net energy (NE) utilization or carcass traits (P ≥ 0.16). Bunks were managed using a slick bunk approach and all diets contained (DM basis) 33 mg/kg monensin sodium. Implant status was checked on d 28 by a single trained evaluator; steers with missing implants were immediately re-implanted. There was no difference in carcass-adjusted growth performance between implants (P ≥ 0.85). There were no differences in observed NE or the observed-to-expected ratio of NE for either growth or maintenance (P ≥ 0.90). No differences were observed for dressing percent, hot carcass weight, ribeye area, or rib fat (P ≥ 0.22). Marbling differed between implant treatments (433 to 466 ± 8.7; P = 0.01) for PLUS and ONE respectively. Implanting cattle with a coated implant had no detrimental effect on growth performance or carcass traits, but it did increase marbling scores.

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Evaluation of Bacillus subtilis PB6 on feedlot phase growth performance, efficiency of dietary net energy utilization, and fecal and subiliac lymph node Salmonella prevalence in spring placement yearling beef steers fed in southeastern South Dakota1,2,3

Translational Animal Science ◽

10.1093/tas/txab002 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Zachary K Smith ◽

Paul Rand Broadway ◽

Keith R Underwood ◽

Warren C Rusche ◽

Julie A Walker ◽

...

Keyword(s):

Bacillus Subtilis ◽

Lymph Node ◽

Lymph Nodes ◽

Growth Performance ◽

Energy Utilization ◽

Management Approach ◽

Net Energy ◽

Beef Steers ◽

Phase Growth ◽

Fecal Samples

Abstract Yearling crossbred beef steers [N = 238; initial shrunk body weight (BW) = 402 ± 31.2 kg] were used to investigate the influence of a Bacillus subtilis probiotic on animal growth performance, efficiency of dietary net energy (NE) utilization, carcass characteristics, and fecal and subiliac lymph node Salmonella prevalence during a 140-d finishing period at the Southeast Research Farm in Beresford, SD. Steers were allotted to 1 of 24 pens (N = 9–10 steers/pen) and assigned to 1 of 2 dietary treatments (12 pens/treatment): no probiotic (CON) or 0.5 g/steer/d of a B. subtilis PB6 probiotic (CLOSTAT500, Kemin Industries, Des Moines, IA; CLO). Bunks were managed according to a slick bunk management approach. Fecal samples were collected on study days 1, 28, 56, 112, and 140 from a subsample of steers from each pen (N = 5 steers/pen) via rectal palpation and composited by pen for the determination of Salmonella prevalence using selective enrichment and culture media. Upon harvest, subiliac lymph nodes were obtained from an equal number of steers from each treatment (collected from every other steer) following evisceration and hide removal. Data were analyzed as a randomized complete block design and pen served as the experimental unit; an α of 0.05 determined significance. Live-basis final BW and average daily gain tended (P ≤ 0.06) to be reduced for CLO. No differences were detected (P ≥ 0.11) between treatments for dry matter intake or gain efficiency. Treatment neither altered the efficiency of dietary NE utilization nor calculated dietary NE content based upon observed performance (P ≥ 0.46). No differences were detected between treatments for any carcass traits (P ≥ 0.15). No Salmonella was recovered in any fecal samples collected on study days 1, 28, or 56. On day 112, steers from CLO had a numerically lower (P = 0.17; 25.0 vs. 8.3%) incidence of fecal Salmonella compared to CON. On study day 140, fecal Salmonella incidence did not differ between treatments (P = 0.34; 0.0 vs. 8.3%) for CON and CLO, respectively. Upon harvest, no Salmonella was recovered in any subiliac lymph nodes. These data indicate that B. subtilis PB6 did not influence feedlot phase growth performance or fecal Salmonella prevalence. Additionally, Salmonella was not observed in the subiliac lymph nodes of any steers upon harvest.

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21 Effect of Corn Silage Inclusion Rate on Live Growth Performance, Carcass Characteristics, Net Energy Utilization and Beef Production Per Hectare in Feedlot Finishing Steers

Journal of Animal Science ◽

10.1093/jas/skab054.045 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 25-26

Author(s):

Elizabeth M Buckhaus ◽

Zachary K Smith

Keyword(s):

Growth Performance ◽

Corn Silage ◽

Energy Utilization ◽

Net Energy ◽

Beef Steers ◽

Beef Production ◽

Finishing Cattle ◽

Finishing Steers ◽

Inclusion Rate ◽

Dietary Treatments

Abstract Maine-Anjou × Angus beef steers (n = 156; initial BW 366 ± 37.2 kg) were used in a finishing experiment at the Ruminant Nutrition Center in Brookings, SD. Steers were weighed on 2 consecutive days and assigned into 5 weight blocks (replicate pens). Treatments were arranged in a 2 × 2 factorial, 2 types of implants and 2 dietary treatments. Dietary treatments consisted (DM basis) of 1) 15% (CS15) or 2) 30% corn silage (CS30). Other ingredients consisted of DRC, HMC, liquid supplement and a dry supplement. The NEm, NEg and CP of CS15 was 94.8 Mcal/45.4 kg, 64.0 Mcal/45.4 kg and 12.7% and 91.2 Mcal/45.4 kg, 61.1 Mcal/45.4 kg, and 12.5% respectively (DM basis) for CS30. Bunks were managed using a slick bunk approach and all diets contained (DM basis) 33 mg/kg monensin sodium. Corn silage yield was assumed to be 45.7 Mg/ha and corn grain yield was calculated to be 10.2 Mg/ha. Beef production per hectare was calculated as (carcass adjusted final BW – initial BW)/hectare. No interaction between diet and implant (P ≥ 0.16) was detected for any variables. Final BW, ADG, and G:F were increased (P ≤ 0.02) by 2.2%, 6.5% and 7.2% respectively for CS15. Observed NE and the ratio of observed-to-expected NE for maintenance and gain was not influenced (P ≥ 0.15) by treatment. Dressing percent (64.52 vs. 63.47 ± 0.250; P = 0.01) and HCW (379 vs. 371 ± 13.1 kg; P = 0.02) were greater in CS15. Beef production per hectare was not impacted (P = 0.76) by feeding greater levels of corn silage. Feeding CS15 resulted in greater carcass-adjusted growth performance and HCW. No differences in beef produced per hectare of crop land means producers can feed greater inclusions of corn silage to finishing cattle without impacting carcass quality or beef production.

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189 Evaluation of Hybrid Rye on Growth Performance, Carcass Traits, and Efficiency of Net Energy Utilization in Finishing Steers

Journal of Animal Science ◽

10.1093/jas/skaa278.293 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 160-160

Author(s):

Warren C Rusche ◽

Julie Walker ◽

Rebecca S Brattain ◽

Zachary K Smith

Keyword(s):

Growth Performance ◽

Carcass Traits ◽

Energy Utilization ◽

Experimental Unit ◽

Net Energy ◽

Complete Replacement ◽

Finishing Diets ◽

Randomized Design ◽

Finishing Steers ◽

Hybrid Rye

Abstract Predominately Angus steers (n = 240, initial shrunk BW 404 ± 18.5 kg) were used in a 117d feedlot experiment to evaluate the effect of hybrid rye (KWS Cereals USA, LLC, Champaign, IL; Rye) as a replacement for dry-rolled corn (DRC) on growth performance, carcass traits, and comparative net energy value in diets fed to finishing steers. Rye from a single hybrid (KWS Bono) with an ergot alkaloid concentration of 392 ppb was processed with a roller mill to a processing index (PI) of 78.8 ± 2.29. Four treatments were used in a completely randomized design (n = 6 pens/treatment, 10 steers/pen) where DRC (PI = 86.9 ± 4.19) was replaced by varying proportions of Rye [DRC:Rye, DM Basis (60:0), (40:20), (20:40), and (0:60)]. Liver abscess scores and carcass characteristics were collected at the harvest facility. Carcass-adjusted performance was calculated from HCW/0.625. Performance-adjusted NE was calculated using carcass-adjusted ADG, DMI, and mean equivalent shrunk BW with the comparative NE values for Rye calculated using the replacement technique. Data were analyzed using the GLIMMIX procedure with pen as the experimental unit. Means were separated using linear and quadratic contrasts. Replacing DRC with Rye linearly decreased (P ≤ 0.01) carcass-adjusted final BW, ADG, DMI and G:F. Feeding Rye linearly decreased HCW and LM area (P ≤ 0.04). Distributions of liver scores and USDA grades for quality and yield were unaffected by treatment (P ≥ 0.09). Using observed performance from d 19 to d 117 (period when steers were on final diet), the estimated replacement NEm and NEg values for Rye were 1.93 and 1.26 Mcal/kg, respectively. Rye can be a suitable feed ingredient in finishing diets for feedlot steers with the optimal inclusion in this experiment at 20% of DM. Complete replacement of DRC with Rye depressed DMI, ADG, and G:F.

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