Jase J. Ball , PAS, Patrick C. Taube , John W. Hallberg , Lilian Franz , Jezaniah Kira Tena , Angela N. Nadrasik , Nicole L. Eberhart , Shelby L. Jones , Karmella D. Borchers , Jordan A. Scramlin , David T. Bechtol , Audie R. Waite , Matthew D. Edmonds , Ryan T. Herrick , PAS, Kelly F. Lechtenberg , Ty E. Lawrence , PAS
{"title":"Reimplant strategies improve rate of weight gain in growing beef steers and heifers fed in confinement for slaughter for at least 200 days","authors":"Jase J. Ball , PAS, Patrick C. Taube , John W. Hallberg , Lilian Franz , Jezaniah Kira Tena , Angela N. Nadrasik , Nicole L. Eberhart , Shelby L. Jones , Karmella D. Borchers , Jordan A. Scramlin , David T. Bechtol , Audie R. Waite , Matthew D. Edmonds , Ryan T. Herrick , PAS, Kelly F. Lechtenberg , Ty E. Lawrence , PAS","doi":"10.15232/aas.2023-02449","DOIUrl":null,"url":null,"abstract":"<div><h3>Objective</h3><p>Our objective was to evaluate growth performance of feedlot steers and heifers administered a sham terminal implant or Synovex Choice, Synovex Plus, or Synovex ONE Feedlot terminal implant 60 or 120 d after initial implantation with Synovex Choice.</p></div><div><h3>Materials and Methods</h3><p>Two studies (steer and heifer) were conducted across 4 locations using 2,400 crossbred steers (n = 1,200; BW = 300.5 ± 31.1 kg) and heifers (n = 1,200; BW = 296.5 ± 27.5 kg). Within sex, cattle were blocked by BW and pen and randomized to 1 of 4 treatments: (1) Choice-Sham, initial implant of Synovex Choice (Zoetis Inc., Parsippany, NJ; 100 mg of trenbolone acetate [TBA] and 14 mg of estradiol benzoate [EB]) fol- lowed by terminal reimplantation of an empty needle; (2) Choice-Choice, initial implant of Synovex Choice followed by terminal reimplantation with Synovex Choice; (3) Choice-Plus, initial implant of Synovex Choice followed by terminal reimplantation with Synovex Plus (Zoetis Inc.; 200 mg of TBA and 28 mg of EB); and (4) Choice-One, initial implant of Synovex Choice followed by terminal reimplantation with Synovex ONE Feedlot (Zoetis Inc.; 200 mg of TBA and 28 mg of EB). Within sex, each site was assigned randomly to reimplant on either d 60 or 120. Data were pooled across reimplant interval by sex. Within sex, animal was the experimental unit and treatments were commingled within pen (n = 3 or 4 pens per site per sex). Body weights were recorded on d 0 and 200.</p></div><div><h3>Results and Discussion</h3><p>Overall ADG from d 0 to 200 was greater for steers (<em>P</em> < 0.01) and heifers (<em>P</em> ≤ 0.02) in the Choice-Choice, Choice-Plus, and Choice-One treatments compared with Choice-Sham, with no differences (<em>P</em> ≥ 0.15) between reimplant treatments. Minimal differences were noted in implant site retention and reaction rates between treatments within sex. There were no differences (steers, <em>P</em> = 0.67; heifers, <em>P</em> = 0.51) between treatments for the percentage of deads and removals nor the incidence of bullers (<em>P</em> = 0.80).</p></div><div><h3>Implications and Applications</h3><p>Synovex Choice as an initial implant followed by terminal implantation with Synovex Choice, Synovex Plus, or Synovex ONE Feedlot 60 to 120 d later improves ADG in feedlot steers and heifers for at least 200 d.</p></div>","PeriodicalId":8519,"journal":{"name":"Applied Animal Science","volume":"39 6","pages":"Pages 472-483"},"PeriodicalIF":1.4000,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590286523000721/pdf?md5=4caf927c0d1684bfdccf1dfa006dc195&pid=1-s2.0-S2590286523000721-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Animal Science","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2590286523000721","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"AGRICULTURE, DAIRY & ANIMAL SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Objective
Our objective was to evaluate growth performance of feedlot steers and heifers administered a sham terminal implant or Synovex Choice, Synovex Plus, or Synovex ONE Feedlot terminal implant 60 or 120 d after initial implantation with Synovex Choice.
Materials and Methods
Two studies (steer and heifer) were conducted across 4 locations using 2,400 crossbred steers (n = 1,200; BW = 300.5 ± 31.1 kg) and heifers (n = 1,200; BW = 296.5 ± 27.5 kg). Within sex, cattle were blocked by BW and pen and randomized to 1 of 4 treatments: (1) Choice-Sham, initial implant of Synovex Choice (Zoetis Inc., Parsippany, NJ; 100 mg of trenbolone acetate [TBA] and 14 mg of estradiol benzoate [EB]) fol- lowed by terminal reimplantation of an empty needle; (2) Choice-Choice, initial implant of Synovex Choice followed by terminal reimplantation with Synovex Choice; (3) Choice-Plus, initial implant of Synovex Choice followed by terminal reimplantation with Synovex Plus (Zoetis Inc.; 200 mg of TBA and 28 mg of EB); and (4) Choice-One, initial implant of Synovex Choice followed by terminal reimplantation with Synovex ONE Feedlot (Zoetis Inc.; 200 mg of TBA and 28 mg of EB). Within sex, each site was assigned randomly to reimplant on either d 60 or 120. Data were pooled across reimplant interval by sex. Within sex, animal was the experimental unit and treatments were commingled within pen (n = 3 or 4 pens per site per sex). Body weights were recorded on d 0 and 200.
Results and Discussion
Overall ADG from d 0 to 200 was greater for steers (P < 0.01) and heifers (P ≤ 0.02) in the Choice-Choice, Choice-Plus, and Choice-One treatments compared with Choice-Sham, with no differences (P ≥ 0.15) between reimplant treatments. Minimal differences were noted in implant site retention and reaction rates between treatments within sex. There were no differences (steers, P = 0.67; heifers, P = 0.51) between treatments for the percentage of deads and removals nor the incidence of bullers (P = 0.80).
Implications and Applications
Synovex Choice as an initial implant followed by terminal implantation with Synovex Choice, Synovex Plus, or Synovex ONE Feedlot 60 to 120 d later improves ADG in feedlot steers and heifers for at least 200 d.