Investigating the effects of a novel rumen-protected folic acid supplement on feedlot performance and carcass characteristics of beef steers

Abstract Angus-crossbred steers (n = 180; 292 ± 18 kg) from a single ranch were used to investigate the effects of a novel rumen-protected folic acid (RPFA) supplement on feedlot performance and carcass characteristics. On d 0, steers were blocked by body weight to pens (5 steers/pen), and pens within a block were randomly assigned to dietary treatments (n = 6 pens/treatment): target intake of 0 (CON), 30 (RPFA-30), 60 (RPFA-60), 90 (RPFA-90), 120 (RPFA-120), or 150 (RPFA-150) mg RPFA·steer -1·d -1. Steers were weighed before feeding on d -1, 0, 55, 56, 86, 87, 181, and 182. Pen average daily gain (ADG), dry matter intake (DMI), and gain:feed (G:F) were calculated for growing (d 0 to 56), dietary transition (d 56 to 87), finishing (d 87 to 182), and overall (d 0 to 182). Liver and blood samples were collected from two steers/pen before trial initiation and at the end of growing and finishing. Steers were slaughtered on d 183, and carcass data were collected after a 48-h chill. Data were analyzed as a randomized complete block design using ProcMixed of SAS 9.4 (fixed effects of treatment and block; experimental unit of pen). Liver abscess scores were analyzed using the Genmod Procedure of SAS 9.4. Contrast statements assessed the polynomial effects of RPFA. Supplemental RPFA linearly increased plasma folate at the end of growing and finishing (P < 0.01), and linearly decreased plasma glucose at the end of growing (P = 0.01). There was a cubic effect of RPFA on liver folate at the end of growing (P = 0.01), driven by lesser concentrations for RPFA-30, RPFA-60, and RPFA-150. Growing period ADG and G:F were greatest for CON and RPFA-120 (cubic P ≤ 0.03). Transition period DMI was linearly increased due to RPFA (P = 0.05). There was a tendency for a cubic effect of RPFA on the percentage of livers with no abscesses (P = 0.06), driven by a greater percentage of non-abscessed livers in RPFA-30 and RPFA-60. Despite supplementing 1 mg Co/kg DM, and regardless of treatment, plasma vitamin B12 concentrations were low (< 200 pg/mL), which may have influenced the response to RPFA as vitamin B12 is essential for recycling of folate.

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287 Effects of a Novel Rumen-protected Folic Acid Supplement on Feedlot Performance and Carcass Characteristics of Beef Steers

Journal of Animal Science ◽

10.1093/jas/skab235.295 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 160-161

Author(s):

Erin L Deters ◽

Emma Niedermayer ◽

Olivia N Genther-Schroeder ◽

Christopher Blank ◽

Remy Carmichael ◽

...

Keyword(s):

Folic Acid ◽

Liver Abscess ◽

Fixed Effects ◽

Block Design ◽

Average Daily Gain ◽

Experimental Unit ◽

Beef Steers ◽

Feedlot Performance ◽

Growing Period ◽

Dietary Treatments

Abstract To assess effects of a novel rumen-protected folic acid (RPFA) supplement, 180 Angus-cross steers (292 ± 18 kg) were blocked by body weight to pens and randomly assigned to dietary treatments (n = 6 pens/treatment): target intake of 0 (CON), 30 (RPFA-30), 60 (RPFA-60), 90 (RPFA-90), 120 (RPFA-120), or 150 (RPFA-150) mg RPFA·steer-1·d-1. Steers were weighed on d -1, 0, 55, 56 (end of growing), 86, 87, 181, and 182. Liver and blood were collected (two steers/pen) before trial initiation and at the end of growing and finishing. Data were analyzed as a randomized complete block design using ProcMixed of SAS (fixed effects of treatment and block; experimental unit of pen). Liver abscess scores were analyzed using ProcGenmod of SAS. Contrast statements evaluated polynomial effects of RPFA and compared CON vs. RPFA-30. At end of growing, RPFA linearly increased plasma folic acid (P < 0.01) and linearly decreased plasma glucose (P = 0.01). Liver folic acid concentrations at end of growing were greatest for CON, RPFA-90, and RPFA-120 (cubic P = 0.01), and growing period (d 0 to 56) average daily gain and gain:feed were greatest for CON and RPFA-120 (cubic P ≤ 0.03). At end of finishing, RPFA linearly increased plasma folic acid concentrations (P < 0.01), and liver folic acid concentrations were lesser for CON vs. RPFA-30 (P = 0.04). Severe liver abscess percentage tended to be greater for CON vs. RPFA-30 (P = 0.09), while dressing percent was lesser for CON vs. RPFA-30 (P = 0.04). Overall (d 0 to 182) carcass-adjusted gain:feed tended to be greater for CON vs. RPFA-30 (P = 0.09). Although RPFA increased plasma folic acid concentrations throughout the study, feedlot performance was not improved, possibly due to low vitamin B12 status (plasma < 200 pg/mL) of steers, regardless of treatment.

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Effects of various ractopamine hydrochloride withdrawal periods on performance, health, and carcass characteristics in yearling steers

Translational Animal Science ◽

10.1093/tas/txz148 ◽

2019 ◽

Vol 4 (1) ◽

pp. 67-74

Author(s):

Tony C Bryant ◽

Josh I Szasz ◽

Lois F G Pringle ◽

Eddie Crispe ◽

K Shawn Blood ◽

...

Keyword(s):

Feed Efficiency ◽

Dry Matter ◽

Block Design ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Average Dose ◽

Withdrawal Period ◽

Feedlot Performance ◽

Dressing Percentage ◽

Ractopamine Hydrochloride

Abstract Ractopamine hydrochloride (RAC) is a β-adrenergic agonist approved for feeding during the last 28 to 42 d prior to cattle slaughter to improve feedlot performance and carcass characteristics. Three thousand crossbred yearling steers (527 ± 2.4 kg; AVG ± SD) were used in two periods to evaluate the effects of various RAC withdrawal times on feedlot performance, health, and carcass characteristics. In Period 1, 6 blocks of 30 pens totaling 1,500 steers were utilized, which was repeated for Period 2. In a randomized complete block design, cattle were assigned to 1 of 5 treatments consisting of 1) No RAC fed (CON), 2) 12-h RAC withdrawal (12-hRAC), 3) 2-d RAC withdrawal (2-dRAC), 4) 4-d RAC withdrawal (4-dRAC), and 5) 7-d RAC withdrawal (7-dRAC). Cattle were fed for a total of 62 d, and applicable treatments were supplemented with 30.0 ppm (dry matter basis) of RAC (average dose = 322 mg per steer per day) for 33 d at the end of the feeding period, corresponding to their respective withdrawal times. Initial body weight (BW) displayed a quadratic curve, with 2-dRAC and 4-dRAC withdrawal periods having the greatest BW. Accordingly, dry matter intake (DMI) responded quadratically (P = 0.034), with 2-dRAC and 4-dRAC treatments demonstrating the greatest DMI. No significant treatment differences (P ≥ 0.641) were observed in final live BW, average daily gain (ADG), or feed efficiency. Alternatively, when using a common dressing percentage to calculate live BW, cattle on RAC treatments exhibited 7.6 kg additional live BW (P < 0.001) compared to CON cattle. Furthermore, carcass-adjusted ADG and feed efficiency did not differ (P > 0.10) between RAC treatments but were improved compared to the CON treatment (P ≤ 0.002). Hot carcass weight (HCW) was on average 4.9 kg greater (P < 0.001) for RAC treatments vs. CON, and no differences were detected (P > 0.10) among RAC treatments. Within RAC treatments, carcass cutability responded quadratically (P ≤ 0.005) to withdrawal period, with the 2-dRAC and 4-dRAC treatments containing more Yield Grade 4 and 5 and fewer Yield Grade 1 and 2 carcasses than the other RAC treatments. On the basis of the results of this experiment, feeding RAC improves dressing percentage, HCW, and carcass-adjusted BW, ADG, and feed efficiency. Furthermore, extending the RAC withdrawal period to 7 d does not have a significant impact on cattle performance or health and has minimal effects on carcass characteristics.

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Effect of corn processing on growth performance, carcass characteristics, and plasma glucose-dependent insulinotropic polypeptide and metabolite concentrations in feedlot cattle1

Translational Animal Science ◽

10.1093/tas/txaa009 ◽

2020 ◽

Vol 4 (2) ◽

pp. 822-830 ◽

Cited By ~ 1

Author(s):

Tiago B Freitas ◽

Tara L Felix ◽

Wayne Shriver ◽

Francis L Fluharty ◽

Alejandro E Relling

Keyword(s):

Growth Performance ◽

Random Effects ◽

Plasma Glucose ◽

Fixed Effects ◽

Block Design ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Fat Deposition ◽

Metabolite Concentrations ◽

Corn Processing

Abstract The objectives of this trial were to evaluate the association between corn processing, glucose-dependent insulinotropic polypeptide (GIP) concentration, and intramuscular (IM) fat deposition. We hypothesized that steers fed whole shelled corn (WSC) would have a greater IM fat deposition than steers fed cracked corn (CC) due to an increase in plasma GIP concentration. Backgrounded, Angus-cross cattle (initial body weight [BW] = 279 ± 9.8 kg) were used in a randomized complete block design in a feedlot setting for an average of 230 d. Cattle were allotted in 12 pens (6 pens per treatment with 8 animals per pen). There were three blocks: heifers (n = 32, initial BW = 265 ± 1.3 kg), small steers (n = 32, initial BW = 262 ± 1.3 kg), and large steers (n = 32, initial BW = 310 ± 1.4 kg). Two pens within each block were randomly assigned to one of the following treatments: 1) CC or 2) WSC. Animal growth performance, carcass characteristics, and plasma hormone and metabolite concentrations were analyzed using the MIXED procedure of SAS, including the fixed effects of treatment, or treatment, time, and their interaction. Pen and block were included as random effects. Carcass yield and quality grade distributions were compared using the GLIMMIX procedure of SAS. including the fixed effects of treatment and time with pen and block as random effects. Linear regression was used to evaluate the association of plasma GIP concentration and IM fat content. Average daily gain (P = 0.57) and final BW (P = 0.34) were similar, regardless of treatment. Cattle fed CC had reduced (P < 0.01) dry matter intake (DMI) when compared with those fed WSC. This lesser DMI resulted in improved gain:feed ratio (P < 0.01) for cattle fed CC compared with cattle fed WSC. There was no effect (P ≤ 0.33) of corn processing on plasma glucose, plasma GIP concentrations, hot carcass weight, dressing percentage, or marbling score. There was a positive linear relationship (P = 0.03) between IM fat concentration and plasma GIP concentration. In conclusion, feeding CC increased gain:feed ratio compared with WSC, but there was no difference in plasma GIP concentration, whereas plasma GIP concentration appears to be related to IM fat deposition.

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160 Injectable Vitamin C Prior to Transit and Transit Duration Effects on Feedlot Performance, Inflammation, and Muscle Fatigue of Beef Steers

Journal of Animal Science ◽

10.1093/jas/skab054.200 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 121-121

Author(s):

Aubree M Beenken ◽

Erin L Deters ◽

Stephanie L Hansen

Keyword(s):

Vitamin C ◽

Muscle Fatigue ◽

Repeated Measures ◽

Fixed Effects ◽

Average Daily Gain ◽

Blood Parameters ◽

Serum Lactate ◽

Sodium Ascorbate ◽

Experimental Unit ◽

Feedlot Performance

Abstract This study examined the effects of injectable vitamin C (VC) before transport and duration of transit on feedlot performance, inflammation, and muscle fatigue in cattle. One hundred thirty-one, Angus-cross steers (409 ± 4 kg) were stratified by bodyweight (BW) to a 2 × 2 factorial of intramuscular injection (INJ; 20 mL/steer): VC (250 mg sodium ascorbate/mL) or saline (SAL) and road transit duration (DUR): 18 (18; 1,770 km) or 8 h (8; 727 km). On d 0, steers were weighed and received INJ of SAL or VC immediately before transport. Upon return (d 1), BW and blood were collected before steers returned to pens with GrowSafe bunks. Steers were weighed on d 0, 1, 7, 15, 30, 31, 54, and 55. Data were analyzed via ProcMixed of SAS (experimental unit = steer; 32–34 steers/treatment) with fixed effects of INJ, DUR, and the interaction. Blood was collected on d -5, 1, 2, and 3 (9 steers/treatment); blood parameters were analyzed as repeated measures. Average daily gain (ADG) and BW were greater on d 7 and 15 for SAL-18 compared to all other treatments (INJ × DUR, P < 0.01). Final BW, overall ADG, and gain:feed were greater for 18 than 8 (P < 0.01). Injection did not affect BW (P > 0.13) but VC decreased overall dry matter intake compared to SAL (P = 0.03). Steers transported for 18 h had greater serum lactate, haptoglobin, and non-esterified fatty acid concentrations on d 1 compared to steers transported for 8 h (DUR × DAY, P < 0.01). Day 1 plasma ascorbate concentrations were greater for VC and returned to baseline concentrations by d 2 (INJ × DAY, P < 0.01). In contrast to previous work, VC did not improve post-transit performance; however, longer transit duration increased indicators of muscle fatigue and inflammation.

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PSVI-30 Feedlot performance and carcass characteristics of beef steers under intensive management with or without an added nutritional packet

Journal of Animal Science ◽

10.1093/jas/skab235.795 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 446-446

Author(s):

Andrea M Osorio ◽

Kaue Tonelli Nardi ◽

Igor Gomes Fávero ◽

Kaliu G Scaranto Silva ◽

Kymberly D Coello ◽

...

Keyword(s):

Block Design ◽

Random Effect ◽

Vitamin B1 ◽

Carcass Characteristics ◽

Quality Data ◽

Experimental Unit ◽

Beef Steers ◽

Intensive Management ◽

Feedlot Performance ◽

Yeast Saccharomyces Cerevisiae

Abstract The effects of a nutritional packet on performance and carcass characteristics of feedlot beef steers were evaluated. Thirty Angus-crossbred steers (BW = 542 ± 8.4 kg) were used in a randomized complete block design and allocated into pens with SmartFeed (C-Lock; 15 steers/treatment). Steers were consuming a steam-flaked corn-based finishing-diet, ad libitum, for the last 65-d on feed prior to slaughter, in which treatments were: 1) control and 2) a nutritional-packet [0.29% DM basis; live yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g); Vitamin C (5.4 g/kg); Vitamin B1 (13.33 g/kg); NaCl (80 g/kg); KCl (80 g/kg)]. Individual BW was recorded every 14 d and carcass quality data was collected at slaughter. Steer was considered the experimental unit. The MIXED procedure of SAS was used with the fixed effect of treatment and the random effect of block. Total DMI was unaffected (P = 0.610) by treatment from d 0–65; however, control steers had greater (P = 0.030) DMI from d 54–65. The G:F was unaffected (P = 0.830) by treatment from d 0–35; however, it was greater (P ≤ 0.001) for steers fed the nutritional packet from d 0–50, and 0–65. Treatment did not affect (P = 0.920) ADG from d 0–35, however it increased (P ≤ 0.001) ADG from d 0–50 and tended (P = 0.060) to increase ADG from d 0–65. Carcass adjusted final BW tended (P = 0.060) to increase by 28% for treated cattle, whereas the Longissimus dorsi area tended to decrease (P = 0.090). No differences (P = 0.240) were observed for fat thickness, while yield-grade (P = 0.03) increased for treated cattle. The nutritional packet appears to improve performance in the final days of feeding steers under intensive management, and energy partitioning may be altered to fat deposition.

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Growth, performance, and carcass characteristics of feedlot Holstein steers fed ractopamine hydrochloride1

Translational Animal Science ◽

10.1093/tas/txz157 ◽

2019 ◽

Vol 4 (1) ◽

pp. 102-117

Author(s):

Cathy L Lockard ◽

Chris J Richards ◽

Caleb G Lockard ◽

Maggie Youngers ◽

Mariah A Woolsoncroft ◽

...

Keyword(s):

Block Design ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Carcass Weight ◽

Feed Ratio ◽

Negative Effects ◽

Feedlot Performance ◽

Randomized Complete Block Design ◽

Growth Promoting ◽

Daily Gain

Abstract Growth-promoting technologies such as implants, ionophores, and β-agonists improve feedlot performance, efficiency, and carcass characteristics of cattle. The objective of this experiment was to determine the effects of dose and duration of ractopamine hydrochloride (RH) on feedlot performance and carcass characteristics when fed to Holstein steers. A randomized complete block design was used with a 3 × 3 factorial arrangement of treatments with 3 RH doses (0, 300, or 400 mg∙steer−1∙d−1) fed for 3 durations (28, 35, or 42 d). Holstein steers (n = 855; initial body weight [BW] = 448 ± 37 kg) were blocked by BW and randomly allocated to 1 of 9 pens (15 blocks; 9 dose × duration treatment combinations) approximately 72 d before harvest. Weekly pen weights, chute temperament scores, and animal mobility were determined during the RH feeding period. At harvest, carcass data were collected on all steers, and tenderness was measured on steaks from 3 or 4 randomly selected steers from each pen and slice shear force (SSF) was determined on one steak selected from each side of the carcass after aging for 14 or 21 d. For feedlot performance, carcass characteristics, and SSF, no dose × duration interactions were observed (P ≥ 0.11). With increasing RH dose, average daily gain (ADG) and gain-to-feed ratio (G:F) increased linearly (P ≤ 0.01), whereas BW gain increased linearly with RH dose and duration (P ≤ 0.01). Hot carcass weight (P = 0.02) and longissimus muscle (LM) area (P ≤ 0.01) increased linearly with increasing RH dose. The percentage of carcasses in the USDA Yield Grade 2 category increased linearly (P ≤ 0.01) and percentage of carcasses in the USDA Yield Grade 4 category tended (P = 0.08) to decrease linearly as RH dose increased. In the 14-d aged steaks, the percentage of steaks with SSF ≤ 15.3 kg decreased linearly (P ≤ 0.01), whereas the percentage of steaks with ≥20.0 kg SSF increased linearly (P ≤ 0.01) with increasing RH dose. After 21-d aging, there was a tendency (P = 0.06) for a greater percentage of steaks from steers fed RH to have SSF ≥ 20.0 kg (2% of total steaks), but no difference (P ≥ 0.12) in the percentage of steaks with SSF ≤ 19.9 kg. Final chute temperament (P ≥ 0.45) and animal mobility (P ≥ 0.67) scores were not affected by feeding RH. Increasing the dose of RH (300 or 400 mg∙steer−1∙d−1) fed for 28 to 42 d before harvest increased ADG, G:F, hot carcass weight, and LM area when fed to Holstein steers with no negative effects on behavior or mobility. The percentage of steaks classified as not tender improved when steaks were aged for 21 d from steers treated with RH.

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PSIV-15 Determining the effects of increasing levels of xylanase in nutrient adequate diets on growth performance, carcass characteristics of growing-finishing pigs

Journal of Animal Science ◽

10.1093/jas/skaa054.313 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 176-177

Author(s):

Hayden R Kerkaert ◽

Joel M DeRouchey ◽

Steve S Dritz ◽

Robert D Goodband ◽

Mike D Tokach ◽

...

Keyword(s):

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Experimental Unit ◽

Finishing Pigs ◽

Carcass Yield ◽

Distillers Grains With Solubles ◽

Treatment Data ◽

Unit Body Weight

Abstract A total of 1,944 mixed sex growing-finishing pigs (PIC; 337×1050; initial BW of 22.5±0.53 kg) were used in a 131-d growth trial to determine the effects of increasing levels of xylanase in adequate diets on grow-finish pig growth performance and carcass characteristics. The 6 dietary treatments consisted of corn, soybean meal, and dried distillers grains with solubles with added xylanase (Belfeed B 1100 MP; Jefo Nutrition Inc., Saint-Hyacinthe, Quebec) formulated to: 0, 5, 10, 20, 40, and 75 of enzymatic activity for xylanase (IU/kg) with 27 pigs per pen and 12 replicates per treatment. Data were analyzed as a randomized complete block design using lmer function in lme4 package in R with pen considered as the experimental unit, body weight as blocking factor, and treatment as a fixed effect. From d 0 to 70, there was a tendency (quadratic, R=0.068) for average daily gain (ADG) to decrease and then increase with increasing added xylanase, but there was no evidence (R >0.10) of differences for average daily feed intake (ADFI) and feed efficiency (G/F). From d 70 to 131 and overall, there was no evidence of difference (R >0.10) observed for ADG, ADFI, and F/G. There was no evidence for difference (R >0.10) between treatments for number of pigs receiving injectable treatments or mortalities. For carcass traits, increasing xylanase increased then decreased (quadratic, R=0.010) percentage carcass yield. Also, as xylanase increased, percentage lean decreased (linear, R=0.038) and backfat marginally increased (linear, R=0.066). In conclusion, adding increasing levels of xylanase in nutrient adequate diets did not influence growth performance or mortality but did improve carcass yield when intermediate levels were fed.

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250 Effects of Bunk Management and Bulk Density of Steam-flaked Corn on Growth Performance, Carcass Characteristics, and Liver Score of Finishing Beef Cattle Fed Diets Without Tylosin Phosphate

Journal of Animal Science ◽

10.1093/jas/skab054.213 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 127-128

Author(s):

Taylor M Smock ◽

Dale Woerner ◽

Kristin E Hales

Keyword(s):

Growth Performance ◽

Bulk Density ◽

Fixed Effects ◽

Management Strategy ◽

Block Design ◽

Average Daily Gain ◽

Random Effect ◽

Carcass Characteristics ◽

Liver Abscesses ◽

Randomized Complete Block Design

Abstract One hundred ninety-two beef steers (BW = 332 ± 8.2 kg) were used in a randomized complete block design to evaluate the effects of differing bunk management and bulk density of steam-flaked corn (SFC) in a randomized complete block design. A factorial arrangement of treatments was used with: 1) slick bunk management (SBM) + 335 g/L SFC; 2) modified ad libitum bunk management (MAL) + 335 g/L SFC; 3) SBM + 425 g/L SFC; 4) MAL+ 425 g/L SFC. Steers were randomly assigned to treatment within BW block, with 12 pen replications per treatment. Data were analyzed using a mixed model with fixed effects of bunk management, SFC bulk density, and their interaction. Block was included as a random effect. Bunk management strategy did not affect growth performance, carcass characteristics, or liver abscess score (P > 0.10). The average daily gain (ADG) of steers fed 425 g/L SFC was greater (P = 0.05) from days 35 to 105 than those fed 335 g/L SFC; however, overall ADG did not differ (P = 0.36). The DMI of steers fed 425 g/L SFC was greater (P ≤ 0.05) than those fed 335 g/L SFC. Gain-to-feed of steers fed 425 g/L SFC tended (P = 0.10) to be lesser from days 0 to 35 but did not differ overall (P ≥ 0.12). Steers fed 425 g/L SFC tended to have greater backfat and calculated empty body fat (P ≤ 0.07) than those fed 335 g/L SFC and had a greater calculated yield grade (P = 0.05). Steers fed 425 g/L SFC had 43.51% fewer (P = 0.04) liver abscesses. Bunk management strategy did not impact growth performance or carcass characteristics; whereas, SFC processed to 425 g/L increased DMI, fat thickness, and yield grade while resulting in a decreased proportion of liver abscesses.

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202 Determining the effects of increasing dietary standardized ileal digestible lysine levels on growth performance and carcass characteristics of growing-finishing pigs from 29- to 129-kg

Journal of Animal Science ◽

10.1093/jas/skaa054.129 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 72-73

Author(s):

Steve J Kitt ◽

Wayne Cast ◽

Mark Hover ◽

Carine Vier ◽

Chris Sievers ◽

...

Keyword(s):

Mortality Rate ◽

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Experimental Unit ◽

Finishing Pigs ◽

Distillers Grains With Solubles ◽

Dried Distillers Grains ◽

The Difference

Abstract Our objective was to determine the effects of increasing standardized ileal digestible (SID) lysine (Lys) levels on growth performance and carcass characteristics of growing-finishing pigs. A total of 1,013 barrows and gilts (PIC337×Camborough, initially 29.2±0.21 kg) were used in a 112-d growth trial with 25 or 26 pigs per pen and 13 pens per treatment in a randomized complete block design. Diets were corn-soybean meal (SBM)-dried distillers grains with solubles-based, and treatments were achieved through the inclusion of SBM at the expense of corn. Diets were fed in 6 phases and formulated to be iso-caloric within each phase. Treatments consisted of: 1) Low Lys: overall dietary SID Lys levels as 87% of PIC2016 Lys requirement; 2) Medium Lys: overall dietary SID Lys levels as 97% of PIC2016 Lys requirement; 3) High Lys: overall dietary SID Lys levels as 106% of PIC2016 Lys requirement. Experimental data were analyzed using generalized linear mixed models with pen as the experimental unit. Pigs fed High or Medium Lys had greater (P< 0.01) average daily gain compared to pigs fed Low Lys. There was no evidence (P >0.10) for the difference between treatments for average daily feed intake. Pigs fed High Lys had the greatest (P< 0.01) feed efficiency (G:F) followed by Medium Lys, with pigs fed Low Lys with the lowest G:F. Pigs fed High or Medium Lys had greater (P< 0.01) hot carcass weight, loin depth, and lean percentage compared to pigs fed Low Lys. There was no evidence (P >0.10) for treatment effect on carcass yield and backfat. Pigs fed Low Lys had greater removal and mortality rate than those fed High or Medium Lys (P< 0.01). In conclusion, increasing SID Lys over PIC2016 recommendations through increasing SBM levels resulted in increased growth performance and carcass characteristics, and reduced removal and mortality rate of 29- to- 129 kg pigs.

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310 Growth Performance and Carcass Characteristics of Beef Steers Consuming Finishing Diets with an Added Nutritional Packet

Journal of Animal Science ◽

10.1093/jas/skab235.311 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 169-169

Author(s):

Kaue T Tonelli Nardi ◽

Jhones O Onorino Sarturi ◽

Darren D Henry ◽

Francine M Ciriaco ◽

Nelson O Huerta-Leidenz ◽

...

Keyword(s):

Growth Performance ◽

Block Design ◽

Average Daily Gain ◽

Vitamin B1 ◽

Carcass Characteristics ◽

Fat Deposition ◽

Experimental Unit ◽

Thiamine Hydrochloride ◽

Beef Steers ◽

Finishing Diets

Abstract The effects of a nutritional packet fed to beef steers during the final 64 d of the feedlot finishing phase on growth performance and carcass characteristics were evaluated. Crossbred-Angus steers (n = 120; initial BW = 544 ± 52 kg) were assigned to 30 pens (4 steers/pen; 15 pens/treatment) in a randomized complete block design where pen represented the experimental unit. A steam-flaked corn-based finishing diet was fed ad libitum, and treatments were applied as follows: 1) control and 2) 30 g/steer-daily (DM-basis) of the nutritional packet (containing live yeast [8.7 Log CFU of Saccharomyces cerevisiae], vitamin C [5.4 g/kg of Ascorbic acid], vitamin B1 [13.33 g/kg of Thiamine hydrochloride], sodium chloride [80 g/kg] and potassium chloride [80 g/kg]). The nutritional packet used ground corn as a carrier and was included at 1 % of diet DM. Orts were quantified daily (if any) and subtracted from the total dietary DM offered to calculate DM intake. Unshrunk BW were collected on d 0, 21, 42 and 64 before daily feeding at 0630 h. Data were analyzed using the GLIMMIX procedure of SAS. Average daily gain (P = 0.89), dry matter intake (P = 0.57) and, gain:feed (P = 0.66) were not affected by the inclusion of the nutritional packet. The 12th rib fat deposition was increased (P ≤ 0.02) for cattle fed the nutritional packet compared with control (15.70 vs. 13.36 mm, respectively). Consequently, calculated yield grade was also increased (P ≤ 0.03) for cattle consuming the nutritional packet (3.32 vs. 3.02). An improved carcass fat-deposition without any deleterious effects on growth performance potentially warrant less days on feed when cattle receive such nutritional packet.

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