scholarly journals Effects of voluntary removal of ractopamine hydrochloride (Optaflexx) on live performance and carcass characteristics of beef steers

2021 ◽  
Author(s):  
P J Rincker ◽  
J B Allen ◽  
M Edmonds ◽  
M S Brown ◽  
J C Kube
Keyword(s):  
Dry Matter ◽  
Carcass Characteristics ◽  
Carcass Weight ◽  
Dry Matter Intake ◽  
Beef Steers ◽  
Live Performance ◽  
Meet Residue ◽  
Ractopamine Hydrochloride ◽  
The Impact ◽  
Linear Manner

Abstract There is a lack of consistency across the globe in how countries establish tissue ractopamine residue limits and which residue limits are applied to various tissues, particularly for edible noncarcass tissues. Therefore, some US beef slaughter organizations have recommended a 48-h voluntary removal of ractopamine before slaughter in order to meet residue requirements of specific export countries and maintain international trade. Our objective was to assess the impact of voluntary removal of ractopamine hydrochloride (Optaflexx®; Elanco, Greenfield, IN) up to 8 d before slaughter on growth performance and carcass characteristics. Crossbred beef steers (60 pens of 10 animals/pen) with an initial shrunk body weight (BW) of 611.8 ± 10 kg SEM were fed one of six treatments over 42 d. Treatments included a control that did not receive ractopamine, on-label use of ractopamine (0-d withdrawal), and 2, 4, 6, or 8 d of voluntary removal of ractopamine from feed before slaughter. The start of ractopamine feeding (30.1 mg/kg of diet dry matter for 32 d) was staggered so that blocks could be slaughtered on the same day. Dry matter intake was decreased by 0.5 kg/d when ractopamine was fed with a 0-d withdrawal (P = 0.04) compared to the control, but was not altered (P = 0.56) as the duration of ractopamine removal increased from 0 to 8 d. Final BW, total BW gain, and average daily BW gain were increased by feeding ractopamine with a 0-d withdrawal (P = 0.09) compared to the control, but these variables decreased in a linear manner (P = 0.10) as the duration of removal increased from 0 to 8 d. Gain efficiency was improved by 15% (P < 0.01) by feeding ractopamine with a 0-d withdrawal compared to the control, and gain efficiency decreased linearly (P = 0.06) as the duration of ractopamine removal increased. Approximately 2/3 of the increase in gain efficiency remained after 8 d of removal. Hot carcass weight was increased by 6 kg (P = 0.02) by feeding ractopamine with a 0-d withdrawal compared to the control. Measured carcass characteristics were not altered by ractopamine feeding or by removal before slaughter (P ≥ 0.24). The consequences of voluntary removal of ractopamine up to 8 d before slaughter were a linear decrease in live BW gain (0.64 kg/d), poorer gain efficiency, and numerically lighter carcass weight.

scholarly journals 227 Evaluation of reimplant timing with Revalor-200 on steer performance and carcass characteristics

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 127-128
Author(s):  
Caitlin A Coulson ◽  
Bradley M Boyd ◽  
Henry Hilscher ◽  
Brandon L Nuttelman ◽  
Grant I Crawford ◽  
...  
Keyword(s):  
Dry Matter ◽  
Block Design ◽  
Carcass Characteristics ◽  
The Other ◽  
Carcass Weight ◽  
Dry Matter Intake ◽  
Optimal Time ◽  
Trenbolone Acetate ◽  
First Derivative ◽  
Randomized Block Design

Abstract The objective of this study was to evaluate the optimal time to reimplant following an initial implant on performance and carcass characteristics when steers were fed for 180 d. Crossbred steers (n = 800; initial BW = 330 ± 25 kg) were utilized in a generalized randomized block design and assigned randomly to pen, and pen assigned randomly to one of five treatments. Treatments included 5 different days on terminal (DOT) implant (160, 120, 100, 80 or 40 DOT). All steers were given an initial implant (80 mg trenbolone acetate (TBA) + 16 mg estradiol; Revalor-IS) on d 1. Terminal implant consisted of 200 mg TBA + 20 mg estradiol (Revalor-200). Dry matter intake was the least for 40 DOT (P ≤ 0.04), with no differences between the other treatments (P ≥ 0.11). Carcass-adjusted final BW responded quadratically (P = 0.03) with 100 DOT having the greatest final BW but was not different from 120 DOT (P = 0.82). Carcass-adjusted ADG and G:F responded quadratically (P = 0.02 and P < 0.01, respectively). When solved for the first derivative, carcass-adjusted ADG and G:F were maximized at 99 and 87 DOT, respectively. However, there was less than a 2% difference in carcass-adjusted ADG and G:F between 80 and 120 DOT. Hot carcass weight responded quadratically (P = 0.03), with the greatest HCW at 100 DOT. Solving for the first derivative, HCW was optimized at 104 DOT. There were no differences in back fat, marbling, or yield grade (P ≥ 0.27). Overall, administering an initial implant followed by a terminal implant 85 to 105 d prior to harvest increased gain, efficiency, and HCW in steers when fed for 180 d. Minimal changes in performance and carcass characteristics when steers are reimplanted 80 to 120 d prior to harvest suggests flexibility in reimplanting windows.

scholarly journals Impact of feeding cover crop forage containing brassicas to steers during backgrounding on live animal performance, carcass characteristics, and meat color

2021 ◽  
Author(s):  
C E Bakker ◽  
L M Hite ◽  
C L Wright ◽  
D W Brake ◽  
A J Smart ◽  
...  
Keyword(s):  
Cover Crops ◽  
Cover Crop ◽  
Dry Matter ◽  
Carcass Characteristics ◽  
Ground Beef ◽  
Dry Matter Intake ◽  
Feed Ratio ◽  
Animal Performance ◽  
Live Animal ◽  
The Impact

Abstract Brassica cover crops are an option for producers to incorporate into their cropping system to improve soil health and also provide a feed resource for cattle. While brassica cover crops have been widely used for grazing cows, their use as a backgrounding feedstuff is relatively unknown. The objective of this study was to determine the impact of feeding a brassica cover crop mixture during backgrounding on live animal performance and carcass characteristics. Thirty Angus-based steers were assigned to one of two dietary treatments during backgrounding 1) ad libitum access to a diet containing freshly cut brassica cover crop forage (CC) containing radish, turnip, rapeseed, rye grass and a liquid supplement or 2) common Midwestern dry lot growing diet containing silage, soybean meal, grass hay, and a liquid supplement (CON). Steers were assigned to electronic feed bunks (Insentec RIC, Hokofarm Group; Marknesse, Netherlands) for collection of individual feed intake. Diets were formulated to be nutritionally similar on a dry matter basis. Steers were paired by weight across treatments and pair fed. Dry matter intake was calculated daily for steers in the CC treatment and the following day CON steers were allowed access to an equal amount of dry matter using the Insentec RIC system. Steers were weighed weekly and backgrounded for 44 days before transitioning to a common finishing diet and weighed every 28 days. Steers were harvested at an estimated average backfat thickness of 1 cm. Standard carcass data were measured and strip loins and shoulder clods were collected. Instrumental and subjective color was measured on ground beef for 8 days and instrumental color was measured on strip steaks for 11 days. Treatment did not influence carcass characteristics, average daily gain, dry matter intake (P &gt; 0.17). However, CON steers exhibited increased gain to feed ratio (P = 0.02). Additionally, a treatment by d interaction was observed for ground beef discoloration as the CC treatment displayed increased discoloration on day 4, 6, and 7 of case life (P &lt; 0.01). These data indicate that brassicas may be utilized in a backgrounding diet without negatively impacting carcass characteristics but may decrease case life of ground beef.

scholarly journals PSII-19 Effect of zinc and chromium supplementation on performance and carcass characteristics in feedlot steers

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 400-401
Author(s):  
Harrison D Hallmark ◽  
Joanis T Zervoudakis ◽  
Juliana Akamine Torrecilhas ◽  
Luciana K Hatamoto-Zervoudakis ◽  
Henrique Toller ◽  
...  
Keyword(s):  
Dry Matter ◽  
Carcass Characteristics ◽  
Dietary Treatment ◽  
Feedlot Cattle ◽  
The Other ◽  
Carcass Weight ◽  
Dry Matter Intake ◽  
Marbling Score ◽  
Feedlot Steers ◽  
Supplemental Zinc

Abstract One hundred and sixty-five crossbred steers were used in this experiment to investigate the influence of supplemental zinc (Zn) and chromium (Cr) on performance and carcass characteristics of feedlot steers fed steam-flaked corn-based finishing diet. Steers were blocked by initial BW (518.9 ± 8.4 kg) within cattle source (2 sources) and housed in pens containing 6–7 steers per pen. Pens within blocks were randomly assigned to treatments in a 2 x 2 factorial arrangement, with factors being: 30 or 90 mg of Zn/kg DM and 0.0 or 0.25 mg Cr/kg DM. Treatments consisted of: 1) 30 mg Zn/kg DM; 2) 90 mg Zn/kg DM; 3) 30 mg Zn + 0.25 mg Cr/kg DM; and 4) 90 mg Zn/kg + 0.25 mg Cr/kg DM. Zinc was supplemented as ZnSO4 and Cr supplemented as Cr propionate. Steers were individually weighted on 2 consecutive days prior to initiating dietary treatment and on 2 consecutive days at the end of the experiment. Dietary treatment were initiated 64 days prior to slaughter (total days on feed = 240). All cattle were transported to a commercial abattoir on the same day and slaughtered. Steers receiving supplemental Cr had greater final BW (P &lt; 0.02) and ADG (P &lt; 0.03) when compared to non-Cr supplemented steers. Additionally, hot carcass weight (P &lt; 0.005) and marbling score (P &lt; 0.03) were greater (P &lt; 0.005) for steers receiving 30 mg Zn/kg DM + 0.25 mg Cr/kg DM when compared with all other treatments. Dry matter intake, morbidity and mortality, and all the other carcass measurements were similar across treatments. These data indicate that under the conditions of this experiment, Zn and Cr supplementation may influence feedlot cattle growth and carcass characteristics.

scholarly journals Influence of Feeding Peanut Skins on Performance of Gulf Coast Ewe Lambs

2017 ◽  
Vol 1 (2) ◽  
pp. 20-24 ◽  
Author(s):  
Gamal M. Abdelrahim ◽  
J. Khatiwada ◽  
D. Rankins ◽  
N. Gurung ◽  
A. Gueye
Keyword(s):  
Dry Matter ◽  
Gulf Coast ◽  
Carcass Characteristics ◽  
Carcass Weight ◽  
Dry Matter Intake ◽  
Experimental Unit ◽  
Feeding Trial ◽  
Ewe Lambs ◽  
Peanut Skins ◽  
Dietary Treatments

The effects of varying levels of dietary peanut skins (PS) inclusion on dry matter intake (DMI), growth, and carcass characteristics of lambs was assessed in 135-d feeding trial. We hypothesized that supplementing lambs’ diet with increasing levels of PS would increase DMI, enhance body growth, and impact carcass characteristics. Thus, the overall objective of the study was to gain a thorough understanding of the feeding value of PS to lambs. Twelve Gulf Coast ewe lambs (27.75 ± 0.93 kg initial body weight (BW) and 7 to 8 months of age) were blocked by BW and were randomly assigned within block to 1 of the 3 dietary treatments. Lambs were grouped in 2 pens per treatment (2 lambs/pen; n = 4/dietary treatment) with pen serving as the experimental unit. Lambs were fed dietary treatments containing 0 (control), 20, or 40% PS (DM basis) as a replacement for corn and SBM. Control diet contained dry-rolled corn, SBM, and fescue/Bermuda grass hay at forage to concentrate ratio of 63:37. All diets were formulated to meet or exceed the NRC requirements of the finishing lambs. At the end of the feeding trial, lambs were slaughtered, and carcass data were collected after a 48-h chill. Dry matter intake and final BW were not different among treatments (P >0.05). Also, no differences were observed in hot carcass weight (HCW; P = 0.57), cold carcass weight (CCW; P = 0.24), body wall fat (P = 0.06), 12th rib fat (P = 0.10), and kidney and pelvic fat (K&P fat; P = 0.65) among treatments. However, rib eye area (REA) was greater (P < 0.01) in lambs fed 0% and 20% PS than in lambs fed 40% PS. These results suggest that PS can replace a portion of corn and SBM commonly fed to lambs without any adverse effects on carcass characteristics or lambs performance. Thus, PS needs to be seriously considered as a potential low-cost feedstuff for ruminants.

scholarly journals 401 Effect of zinc source and ractopamine hydrochloride on the growth performance and carcass characteristics of steers fed in confinement to harvest

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 160-160
Author(s):  
John Wagner ◽  
William T Nelson ◽  
Terry Engle ◽  
Jerry Spears ◽  
Jeff Heldt ◽  
...  
Keyword(s):  
Feed Efficiency ◽  
Average Daily Gain ◽  
Carcass Characteristics ◽  
Feedlot Cattle ◽  
Beef Steers ◽  
Live Animal ◽  
Zinc Source ◽  
Dressing Percentage ◽  
Ractopamine Hydrochloride ◽  
Daily Gain

Abstract Four hundred and thirty-two beef steers (346.3 ± 63.7 kg BW) were used to determine the effects of Zn source on feedlot cattle fed ractopamine hydrochloride. Cattle were blocked in groups of 54 by BW and housed in 48 pens containing 9 steers per pen. Pens within a weight block were randomly assigned to treatments in a 2 x 3 factorial arrangement, with factors being: 1) 0 or 30.1 mg of ractopamine HCl/kg DM fed during the final 29 days on feed; and 2) Zn source: 90 mg of supplemental Zn/kg DM from ZnSO4; Zn sulfate (67%) + Zn methionine (33%); and Zn from Zn hydroxychloride, fed through the entire feeding period. Cattle were fed a high concentrate finishing diet for 154 d and slaughtered at a commercial abattoir. Average daily gain, DMI, feed efficiency and carcass characteristics were determined after slaughter. Zinc source had no impact on live animal performance. Cattle fed ractopamine HCl had greater (P &lt; 0.01) final BW, greater (P &lt; 0.001) ADG, improved (P &lt; 0.001) G:F, heavier (P &lt; 0.01) HCW, and larger (P &lt; 0.05) longissimus muscle compared to non-ractopamine supplemented steers. There was a Zn source by ractopamine interaction (P &lt; 0.01) for dressing percentage. Cattle receiving ractopamine HCl with Zn hydroxychloride had a greater dressing percentage (P &lt; 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Cattle receiving ractopamine HCl with Zn sulfate had a lesser dressing percentage (P &lt; 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Additional Zn source by ractopamine HCl interactions were not significant. These data indicate that Zn source has minimal impacts on feedlot steer performance and carcass characteristics when supplemented to cattle receiving 0.0 or 30.1 mg of ractopamine HCl/kg DM.

UTILIZATION OF GRASS SILAGE BY CATTLE: EFFECT OF BARLEY AND FISHMEAL SUPPLEMENTS

1985 ◽  
Vol 65 (4) ◽  
pp. 897-903 ◽  
Author(s):  
D. M. VEIRA ◽  
M. IVAN ◽  
G. BUTLER ◽  
J. G. PROULX
Keyword(s):  
Formic Acid ◽  
Nitrogen Content ◽  
Dry Matter ◽  
Dry Matter Intake ◽  
Beef Steers ◽  
Large Reduction ◽  
High Nitrogen Content ◽  
High Nitrogen ◽  
Grass Silage ◽  
Ad Libitum

Following weaning at 6–7 mo of age, 36 beef steers were used to determine production responses when grass silage was supplemented with barley or fishmeal. The silage was made from direct-cut, formic- acid-treated grass harvested from a mixed sward and had a high nitrogen content but poor fermentation characteristics. The silage was fed ad libitum for 98 days either alone or supplemented with 500 g fishmeal or 500 g barley per day. Both fishmeal and barley increased total dry matter intake (P < 0.01) by an amount equivalent to the quantity of supplement offered but had no effect on silage intake (P > 0.05). Steers fed the fishmeal grew substantially faster than either the barley (0.53 kg/day) or unsupplemented (0.54 kg/day) groups (P < 0.01). Fishmeal supplementation resulted in a large reduction (35%) in the amount of feed required per kilogram of gain. Key words: Cattle, grass silage, fishmeal, growth

scholarly journals Effects of the association between whole cottonseed and calcium salts of fatty acids on nutrient intake, feedlot performance, and carcass characteristics of Bos indicus animals offered a high-concentrate diet

2021 ◽  
Author(s):  
Leonardo R. Müller ◽  
Daniel I C. G. Gouvêa ◽  
André F. Francischinelli ◽  
Guiherme D. A. Alvarenga ◽  
Pablo C Castagnino ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Soybean Oil ◽  
Feed Efficiency ◽  
Dry Matter ◽  
Bos Indicus ◽  
Carcass Characteristics ◽  
Dry Matter Intake ◽  
Feedlot Performance ◽  
Calcium Salts ◽  
Whole Cottonseed

Abstract This experiment evaluated the effects of feeding whole cottonseed (WC) and/or calcium salts of fatty acids (CSFA) on dry matter intake (DMI), performance, and carcass characteristics of Bos indicus animals receiving a high-concentrate diet during the finishing phase. On day 0, 96 Nellore bulls were blocked according to initial shrunk body weight (BW; 302 ± 26.7 kg) into group pens (4 animals/pen) and, within blocks, pens were randomly assigned to receive: 1) 15% of WC and 2% of CSFA [dry matter (DM) basis] of palm, cottonseed, and soybean oil (15WC; n = 6), 2) 10% of WC and 3% of CSFA (DM basis) of palm, cottonseed, and soybean oil (10WC; n = 6), 3) 5% of WC and 4% of CSFA (DM basis) of palm, cottonseed, and soybean oil (5WC; n = 6), and 4) 0% of WC and 5% of CSFA (DM basis) of palm, cottonseed, and soybean oil (0WC; n = 6). Diets were formulated to be isocaloric, isonitrogenous, and isolipidic. Experimental period lasted 108 days, whereas dry matter intake (DMI) was evaluated daily and blood samples and carcass measurements were obtained on days 0, 55, and 108 of the study. Upon slaughter on day 109, steaks were collected for determination of the chemical and fatty acid (FA) profile of the meat. No treatment effects (P ≥ 0.35) were observed on DMI, performance, average daily gain (ADG), carcass ultrasound measurements, and chemical variables of the steak. Nonetheless, including WC into the diets increased C12:0, C16:0, C16:1 trans-9, C17:0, C18:0, C18:1 cis-9, C18:2 cis-9,cis-12, C18:3 cis-9,cis-12,cis-15, saturated, and unsaturated FA intake (P &lt; 0.01). Moreover, adding WC increased DMI fluctuation and feed efficiency (P = 0.03), but decreased marbling (P ≤ 0.03). A treatment × day interaction was observed (P &lt; 0.01) for serum leptin concentration, as 10WC animals had greater leptin concentration on d 103 vs. other treatments (P &lt; 0.01). Regarding steak FA profile, WC addition into the diet increased C18:2 cis-7,trans-9 and C18:3 cis-9,cis-12,cis-15 (P &lt; 0.001), whereas saturated FA was quadratically affected (P = 0.02) and unsaturated FA was reduced for 15WC (P &lt; 0.04). In summary, increasing levels of CSFA into isolipidic finishing diets containing WC did not negatively impact feedlot performance, but reduced feed efficiency and increased marbling scores of Bos indicus bulls, demonstrating its feasibility as a technology to improve carcass traits of low-marbling animals.

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

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 &lt; 0.001) compared to CON cattle. Furthermore, carcass-adjusted ADG and feed efficiency did not differ (P &gt; 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 &lt; 0.001) for RAC treatments vs. CON, and no differences were detected (P &gt; 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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