Comparative effects of zilpaterol hydrochloride and ractopamine hydrochloride on live performance and carcass characteristics of calf-fed Holstein steers12

Brown, Tanya M.; Sexten, Andrea K.; Lawrence, T.E.; Miller, M. F.; Thomas, C. L.; Yates, David A.; Hutcheson, J. P.; Hodgen, J. M.; Brooks, J. C.

doi:10.2527/jas.2014-7754

Cited by 9 publications

(7 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar β receptor populations were found in human muscle biopsies [40, 41]. The present findings also help explain greater muscle growth efficiency in food animals supplemented with dietary β2 agonist compared to β1 agonist [42–44]. …”

Section: Discussionsupporting

confidence: 79%

Acute exposure of primary rat soleus muscle to zilpaterol HCl (β2 adrenergic agonist), TNFα, or IL-6 in culture increases glucose oxidation rates independent of the impact on insulin signaling or glucose uptake

et al. 2017

View full text Add to dashboard Cite

Recent studies show that adrenergic agonists and inflammatory cytokines can stimulate skeletal muscle glucose uptake, but it is unclear if glucose oxidation is similarly increased. Thus, the objective of this study was to determine the effects of ractopamine HCl (β1 agonist), zilpaterol HCl (β2 agonist), TNFα, and IL-6 on glucose uptake and oxidation rates in unstimulated and insulin-stimulated soleus muscle strips from adult Sprague-Dawley rats. Effects on phosphorylation of Akt (phospho-Akt), p38 MAPK (phospho-p38), and p44/42 MAPK (phospho-p44/42) was also determined. Incubation with insulin increased (P < 0.05) glucose uptake by ~47%, glucose oxidation by ~32%, and phospho-Akt by ~238%. Insulin also increased (P < 0.05) phospho-p38, but only after 2 hours in incubation. Muscle incubated with β2 agonist alone exhibited ~20% less (P < 0.05) glucose uptake but ~32% greater (P < 0.05) glucose oxidation than unstimulated muscle. Moreover, co-incubation with insulin + β2 agonist increased (P < 0.05) glucose oxidation and phospho-Akt compared to insulin alone. Conversely, β1 agonist did not appear to affect basal or insulin-stimulated glucose metabolism, and neither β agonist affected phospho-p44/42. TNFα and IL-6 increased (P < 0.05) glucose oxidation by ~23% and ~33%, respectively, in the absence of insulin. This coincided with increased (P < 0.05) phospho-p38 and phospho-p44/42 but not phospho-Akt. Furthermore, co-incubation of muscle with insulin + either cytokine yielded glucose oxidation rates that were similar to insulin alone, despite lower (P < 0.05) phospho-Akt. Importantly, cytokine-mediated increases in glucose oxidation rates were not concomitant with greater glucose uptake. These results show that acute β2 adrenergic stimulation, but not β1 stimulation, directly increases fractional glucose oxidation in the absence of insulin and synergistically increases glucose oxidation when combined with insulin. The cytokines, TNFα and IL-6, likewise directly increased glucose oxidation in the absence of insulin, but were not additive in combination with insulin and in fact appeared to disrupt Akt-mediated insulin signaling. Rather, cytokines appear to be acting through MAPKs to elicit effects on glucose oxidation. Regardless, stimulation of glucose oxidation by these key stress factors did not rely upon greater glucose uptake, which may promote metabolic efficiency during acute stress by increasing fractional glucose oxidation without increasing total glucose consumption by muscle.

show abstract

Section: Discussionsupporting

confidence: 79%

Acute exposure of primary rat soleus muscle to zilpaterol HCl (β2 adrenergic agonist), TNFα, or IL-6 in culture increases glucose oxidation rates independent of the impact on insulin signaling or glucose uptake

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Ractopamine hydrochloride has been well established for its impact on HCW; studies have shown consistent improvements when fed at 200 to 300 mg/ (animal • d). Scramlin et al (2010) reported HCW that were 5.3 kg greater in steers supplemented with 200 mg/ (animal • d) compared to controls, and similar improvements were reported by Brown et al (2014), who realized an 8.2-kg increase in steers fed 300 mg/(animal • d).…”

Section: Discussionsupporting

confidence: 63%

Ionophore strategy affects growth performance and carcass characteristics in feedlot steers1

Thompson

Smith

Corbin

et al. 2016

Journal of Animal Science

View full text Add to dashboard Cite

One hundred ninety-two steers (BW = 354 ± 23.5 kg) were used in a randomized block design to evaluate the effects of ionophore and ractopamine hydrochloride (RH) supplementation strategies on performance and carcass characteristics. Twelve pens of 4 steers were assigned to each of the following treatments: unsupplemented control (CON), laidlomycin propionate (12.1 mg/kg DM) with or without RH (LPRH and LP, respectively), and monensin sodium (36.4 mg/kg DM) with RH (MSRH). Steers were fed for 151 d, of which respective treatments received RH (Actogain; Zoetis, Florham Park, NJ) at a rate of 300 mg/(animal · d) for the final 32 d. Laidlomycin was removed from the LPRH treatment during this period, as no combination feeding has been approved. Upon harvest, carcass data were collected by trained personnel, and subsequent analysis of the LM was conducted to estimate tenderness using Warner-Bratzler shear force (WBSF). Prior to RH supplementation, both LP and LPRH had greater ADG ( ≤ 0.02) and G:F ( < 0.01) than CON, whereas MSRH was intermediate. During the final 32 d, MSRH improved G:F ( ≤ 0.02) compared to all other treatments and tended to increase ADG over unsupplemented controls ( = 0.05). Cattle receiving LP without RH had significantly greater BW at d 151 than CON ( = 0.02), whereas both RH treatments tended to improve final BW ( ≤ 0.09). Ionophores improved ADG ( ≤ 0.03) and G:F ( < 0.01) for the entire feeding period, and although LP-supplemented cattle had greater DMI for the final 32 d than both RH treatments ( ≤ 0.01), intakes for the 151-d trial were similar among treatments. Carcass weights were greater ( = 0.04) in cattle fed LP with no RH than CON, where cattle yielded an average of 12 kg more HCW. Ractopamine increased LM area in MSRH-supplemented cattle ( = 0.03) and tended to increase LM area for steers receiving LPRH ( = 0.07). Longissimus steaks of MSRH-supplemented cattle had greater WBSF values than CON ( = 0.04) after 7 d of postmortem aging and greater WBSF values than LPRH steaks after 28 d ( = 0.03). All other carcass and WBSF measurements were similar among treatments. The results of this study indicate that LP supplementation without RH may yield a performance similar to and carcass responses associated with the administration of a β-agonist. These results also suggest that performance and carcass characteristics for cattle fed LP are similar to those of cattle fed monensin throughout the feeding period.

show abstract

“…In spite of the muddy conditions, animal performance data from the present experiment are consistent with results from previous experiments ( Bass et al, 2009 ; Vogel et al, 2009 ; Brown et al, 2014 ) when RH was fed to Holstein steers during the final 28 to 38 d of the feeding period. Previous studies have reported greater BW gain (4.3 to 8.0 kg), increased ADG (0.05 to 0.28 kg/d), and an improvement in G:F (14.2% to 16.6%) in calf-fed or yearling Holstein steers fed 200 to 300 mg·steer −1 ·d −1 of RH compared with steers not fed RH ( Bass et al, 2009 ; Vogel et al, 2009 ; Brown et al, 2014 ). In the present experiment, BW was improved by 6.3 and 7.2 kg, ADG by 0.20 and 0.22 kg/d, and G:F was increased 20.8% and 21.7%, when steers were fed 300 and 400 mg·steer −1 ·d −1 of RH, respectively.…”

Section: Discussionsupporting

confidence: 91%

“…Previous research has shown the addition of RH to the diet of beef or Holstein steers prior to harvest resulted in improvement in average daily gain (ADG), gain-to-feed ratio (G:F), hot carcass weight (HCW), and carcass leanness ( Arp et al, 2014 ; Brown et al, 2014 ; Bittner et al, 2017 ). However, research determining the effects of feeding RH at varying doses and durations in Holstein steers is limited.…”

Section: Introductionmentioning

confidence: 99%

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

Lockard

Richards

Youngers

et al. 2019

Translational Animal Science

View full text Add to dashboard Cite

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.

show abstract

Comparative effects of zilpaterol hydrochloride and ractopamine hydrochloride on live performance and carcass characteristics of calf-fed Holstein steers12

Cited by 9 publications

References 10 publications

Acute exposure of primary rat soleus muscle to zilpaterol HCl (β2 adrenergic agonist), TNFα, or IL-6 in culture increases glucose oxidation rates independent of the impact on insulin signaling or glucose uptake

Acute exposure of primary rat soleus muscle to zilpaterol HCl (β2 adrenergic agonist), TNFα, or IL-6 in culture increases glucose oxidation rates independent of the impact on insulin signaling or glucose uptake

Ionophore strategy affects growth performance and carcass characteristics in feedlot steers1

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

Contact Info

Product

Resources

About