A commercial feedlot trial examined effects of two implant strategies (Revalor- IH on d 1 and re- implanted with Revalor- 200 on d 101 or Revalor- XH on d 1) on growth performance and carcass characteristics of heifers fed 183 days. Th ere were no differences between implant strategies for final body weight, dry matter intake, and average daily gain. Heifers implanted with the combination IH/200 treatment had improved carcassadjusted feed conversion, greater LM area, and lower calculated yield grade compared to heifers implanted with XH. Th e response in growth performance between the two implant strategies suggests that the partiallycoated Revalor- XH implant can be used in place of a more aggressive implant strategy when heifers are fed to similar days

Carlson, Zachary E.

Dicke, Bill D.

Erickson, Galen E.

Streeter, Marshall N.

English

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University of Nebraska - Lincoln 
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Nebraska Beef Cattle Reports Animal Science Department 
2020 
Evaluation of Two Implant Strategies, Revalor- XH or a 
Combination Revalor- IH/Revalor- 200 on Heifer Growth 
Performance and Carcass Characteristics 
Zachary E. Carlson 
University of Nebraska - Lincoln 
Galen E. Erickson 
University of Nebraska - Lincoln, gerickson4@unl.edu 
Bill D. Dicke 
University of Nebraska - Lincoln 
Marshall N. Streeter 
University of Nebraska - Lincoln 
Follow this and additional works at: https://digitalcommons.unl.edu/animalscinbcr 
 Part of the Large or Food Animal and Equine Medicine Commons, Meat Science Commons, and the 
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Carlson, Zachary E.; Erickson, Galen E.; Dicke, Bill D.; and Streeter, Marshall N., "Evaluation of Two Implant 
Strategies, Revalor- XH or a Combination Revalor- IH/Revalor- 200 on Heifer Growth Performance and 
Carcass Characteristics" (2020). Nebraska Beef Cattle Reports. 1088. 
https://digitalcommons.unl.edu/animalscinbcr/1088 
This Article is brought to you for free and open access by the Animal Science Department at 
DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Nebraska Beef Cattle 
Reports by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 
2020 Nebraska Beef Cattle Report · 91 
©  Th e Board Regents of the University of 
Nebraska. All rights reserved.
Zachary E. Carlson
Galen E. Erickson
Bill D. Dicke
Marshall N. Streeter
Summary and Implications
A commercial feedlot trial examined 
eff ects of two implant strategies (Revalor- IH 
on d 1 and re- implanted with Revalor- 200 
on d 101 or Revalor- XH on d 1) on growth 
performance and carcass characteristics of 
heifers fed 183 days. Th ere were no diff erenc-
es between implant strategies for fi nal body 
weight, dry matter intake, and average daily 
gain. Heifers implanted with the combination 
IH/200 treatment had improved carcass- 
adjusted feed conversion, greater LM area, 
and lower calculated yield grade compared 
to heifers implanted with XH. Th e response 
in growth performance between the two 
implant strategies suggests that the partially- 
coated Revalor- XH implant can be used in 
place of a more aggressive implant strategy 
when heifers are fed to similar days.
Introduction
Heifers given increased trenbolone 
acetate and estradiol tend to respond 
with increased growth performance and 
hot carcass weight. Heifers typically have 
reduced growth performance compared 
to steers due to increased fat deposition at 
the same age. To improve growth per-
formance of heifers, feedlots may utilize 
aggressive implant protocols. Implant-
ing once at the beginning of the feeding 
period with a long- lasting, delayed- release 
implant (Revalor- XH) may reduce poten-
tial stressors. Th e objective of this study 
was to evaluate implanting heifers with a 
partially coated Revalor- XH implant on d 
1 compared to a more aggressive implant 
strategy of Revalor- IH on d 1 followed by 
Revalor- 200 at a target of 80 d on terminal 
 Evaluation of Two Implant Strategies, Revalor- XH or a 
Combination Revalor- IH/Revalor- 200 on Heifer Growth 
Performance and Carcass Characteristics
implant. Finishing heifer performance and 
carcass characteristics were measured.
Procedure
Crossbred heifers [n = 870; initial body 
weight (BW) = 710; SD = 19.6 lb] were uti-
lized in a fi nishing study conducted at Hi- 
Gain Feedlot near Farnam, NE. Th e study 
had a generalized randomized block design 
with three blocks and two replications per 
block. Heifers were sourced from Nebras-
ka (two replications), North Dakota and 
Montana (two replications), and Canada (2 
replications). Heifers were fed for an aver-
age of 183 d (range 181– 184 d) from May 
2018 to November 2018. Treatments were: 
Revalor- IH on d 1 (80 mg trenbalone ace-
tate (TBA)/8 mg estradiol (E2), noncoated, 
Merck Animal Health DeSoto, KS) and re- 
implanted with Revalor- 200 on d 101 (200 
mg TBA/20 mg E2, noncoated (IH/200), 
Merck Animal Health) or Revalor- XH on d 
1 (200 mg TBA/20 mg E2, partially coated 
(XH); Merck Animal Health). Revalor- XH 
contains four uncoated pellets (80 mg TBA 
and 8 mg E2) for immediate release and six 
coated pellets (120 mg TBA and 12 mg E2) 
to release approximately 70 to 80 d aft er 
implanting.
Heifers were randomly assigned to 
pen (n = 12) by sorting every two heifers 
into one of two pens within replication 
prior to processing. Heifers were enrolled 
in the study over two days. Heifers were 
processed, pen weighed, and assigned to 
treatment in a single event. Animals were 
blocked based on origin source. Each block 
contained an equal number of pens per 
treatment. Pens were assigned randomly to 
treatment with 6 pens per treatment and 
an average of 73 animals per pen. Prior 
to enrollment, all heifers were checked 
for pregnancy. If pregnant, heifers were 
removed from the pool of qualifi ed ani-
mals. At processing, heifers received their 
assigned implant, vaccine for protection 
against bovine rhinotracheitis virus and 
bovine viral diarrhea types one and two 
viruses (Bovi- shield Gold 5; Zoetis, Flor-
ham Park, NJ), external parasite control via 
dosing with 7 cc of moxidectin (Cydectin, 
Bayer Animal Health, Germany), and 
internal parasite control via drenching with 
17 cc of fenbendazole (Safe- Guard, Merck) 
oral suspension. Implants were placed in 
the middle- third of the ear under the skin. 
Heifers assigned to IH/200 treatment were 
re- implanted 101 d aft er initial implanting. 
At reimplant, all implants were placed in 
the opposite ear of the initial implant.
Cattle were housed in open lots, with 
similar square feet allocated per animal 
across all pens, and ad libitum access to 
water and feed. Diets were constant across 
all treatments. All animals were adapted 
to a common fi nishing diet over a 27- d 
step up period consisting of four adap-
tion diets. Th e fi nishing ration consisted 
of 65.3% steam- fl aked corn, 18.0% wet 
distillers grains plus solubles, 4.5% mixed 
hay, 5.5% corn silage, 1.7% tallow, and 
5.0% supplement (DM basis). Supplement 
was delivered daily via micro machine and 
formulated to provide 30 g/ton DM of Ru-
mensin (Elanco Animal Health), 8.9 g/ton 
DM Tylan (Elanco Animal Health), 0.45 
mg/hd/d of melengestrol acetate (MGA, 
Zoestis) and 250 mg/hd/d DM of Optaf-
lexx (Elanco Animal Health). Th e nutrient 
composition of the fi nishing diet contained 
14.6% crude protein, 6.6% crude fat, 1.04 
Mcal/lb NEm, 0.72 Mcal/lb NEg, 0.7% Ca, 
0.4% P, 0.7% K, and 0.2% S (DM basis). 
Optafl exx was targeted to be fed for 29 d at 
the end of the feeding period with a two d 
withdraw prior to slaughter. Diet samples 
were taken monthly and sent to a commer-
cial laboratory (Servi- Tech Laboratories, 
Hastings, NE) for feed composition (DM, 
CP, NEm, NEg, Ca, P, K, and S). Weekly 
feed ingredient samples were taken to 
determine DM on site.
Cattle were scheduled for slaughter at 
approximately 183 d (range 181– 184 d) 
on feed. Cattle were pen weighed prior to 
loading onto the truck to be shipped. Cattle 
were harvested at varying days on feed. 
Replications one and two were harvested 
at 181 days on feed and replications three, 
92 · 2020 Nebraska Beef Cattle Report
disease, foot rot, or body injury. No dif-
ferences (P > 0.64; Table 1) were observed 
between implant treatments for percent 
removed and mortality.
Th ere were no diff erences (P > 0.23) 
in live fi nal BW, dry matter intake (DMI), 
average daily gain (ADG), and feed conver-
sion (F:G) due to implant treatment. Th ere 
were no diff erences (P > 0.17) in carcass- 
adjusted fi nal BW and ADG among implant 
treatments. Although not signifi cant, 
carcass- adjusted ADG was 1.63% greater 
for heifers implanted with the combination 
IH/200 compared to heifers implanted 
with XH. Carcass- adjusted feed conversion 
improved 2.58% (P = 0.03) for heifers given 
IH/200 compared to heifers implanted with 
XH.
Th ere were no diff erences (P > 0.22) 
in HCW, dressing percent, and 12th rib fat 
thickness among treatments. Heifers im-
planted with IH/200 had greater (P = 0.01) 
LM area compared to heifers implanted 
with XH. Calculated yield grade was greater 
(P = 0.01) for heifers given XH compared 
to heifers implanted with IH/200. Th e 
distribution of USDA yield grades tended 
to be signifi cantly diff erent (P = 0.08; Table 
2) among treatments. Th e distribution of 
USDA quality grades was not diff erent (P = 
0.35) among treatments.
Conclusion
Overall, growth performance and car-
cass characteristics were relatively similar 
among IH/200 and XH treatments. How-
ever, heifers given IH/200 had improved 
carcass- adjusted feed effi  ciency, LM area, 
and calculated yield grade compared to 
heifers given XH. Th ese data suggest when 
heifers are fed the same number of days the 
combination IH/200 implants can improve 
animal performance compared to the XH 
implant.
Zachary E. Carlson, graduate student
Galen E. Erickson, professor, Animal 
Science, University of Nebraska, Lincoln, 
NE
Bill D. Dicke, Dicke Consulting, LLC, 
Lincoln, NE
Marshall N. Streeter, Merck Animal Health, 
De Soto, KS
Treatment and block were fi xed eff ects. 
Th e model included implant treatment 
and block. Pen was the experimental unit. 
Treatment averages were calculated using 
the LSMEANS option of SAS. Frequency 
data, such as USDA quality grade and yield 
grade distributions, were analyzed using the 
GLIMMIX procedure of SAS using a mul-
tinomial approach. Treatment diff erences 
were signifi cant at α ≤ 0.05 and tendencies 
were discussed when 0.05 ≤ α ≤ 0.10.
Results
Th ere were nine heifers that died over 
the course of the study. Sixteen heifers were 
removed from the trial due to respiratory 
four, fi ve, and six were harvested at 184 
days on feed. All heifers were harvested at 
a commercial abattoir (JBS Swift  and Co., 
Grand Island, NE). Individual HCW was 
collected at slaughter. Following a 24- hr 
chill, 12th- rib fat depth, LM area, marbling, 
USDA quality grade, and USDA yield grade 
were collected from camera data. Th ere 
were 11 carcasses removed from analysis 
due to missing carcass data or misidentifi ed 
individual animal IDs. Th erefore, carcass 
data were analyzed with 414 and 420 heifers 
in IH/200 and XH, respectively.
Performance and carcass data were 
analyzed as a generalized randomized 
block design using the MIXED procedure 
of SAS (9.4, SAS Institute Inc., Cary, NC). 
Table 1. Performance and carcass characteristics of heifers implanted with Revalor- XH or 
Revalor- IH/200
Item
Treatment1
SEM F- TestRev- IH/200 Rev- XH
Head Count 435 435 — — 
Days on Feed 183 183 — — 
Animals Removed, % 3.21 2.59 0.901 0.64
Death Loss, % 1.15 0.95 0.509 0.79
Live Performance
Initial BW, lb 713 708 3.3 0.36
Final BW2, lb 1393 1385 6.8 0.43
DMI, lb/d 23.9 24.2 0.18 0.33
ADG, lb 3.72 3.70 0.027 0.62
F:G 6.45 6.54 — 0.23
Carcass- Adjusted Performance
Final BW3, lb 1394 1380 7.3 0.21
ADG, lb 3.73 3.67 0.026 0.17
F:G 6.41 6.58 — 0.03
Carcass Characteristics
HCW, lb 880 871 4.7 0.22
Dressing, % 63.14 62.87 0.17 0.28
LM area, in2 13.7 13.0 0.14 <0.01
Marbling4 512 497 5.6 0.11
12th rib fat, in 0.75 0.74 0.009 0.32
Calculated YG5 3.75 3.89 0.025 <0.01
1Treatments included: 1) Revalor- IH on d 1 (80 mg trenbalone acetate (TBA)/8 mg estradiol (E2), noncoated, Merck Animal 
Health DeSoto, KS) and re- implanted with Revalor- 200 on d 101 (200 mg TBA/20 mg E2, noncoated (IH/200), Merck Animal 
Health); 2) Revalor- XH on d 1 (200 mg TBA/20 mg E2, partially coated (XH); Merck Animal Health). Revalor- XH contains 
four uncoated pellets (80 mg TBA and 8 mg E2) for immediate release and six coated pellets (120 mg TBA and 12 mg E2) to 
release approximately 70 to 80 d aft er implanting.
2Final BW is the average pen weight shrunk four percent. Subsequent ADG and F:G are calculated from shrunk fi nal BW.
3Carcass- adjusted fi nal BW was determined by dividing average HCW per treatment by the average dressing percent of 63.01%.
4USDA marbling scores. 400 = small, 500 = modest, 600 = moderate.
5YG = 2.50 + (2.5 * 12th- rib fat depth, in) + (0.2 * 3.0 KPH fat, %) + (0.0038 * HCW, lbs)— (0.32 * LM area, in2) where KPH fat 
was assumed to be 3.0 %.
2020 Nebraska Beef Cattle Report · 93 
Table 2. Quality grade and yield grade distribution of heifers fed for an average of 183 d implanted 
with Revalor- IH/200 or Revalor- XH
Item
Treatment1
P- ValuesRev- IH/200 Rev- XH
Quality Grade2, %
Prime 4.9 4.7 0.35
Upper Choice 45.2 43.3
Choice 35.8 40.4
Select 13.8 11.2
Standard 0.2 0.3
Yield Grade Distribution2, %
YG 1 0.9 0.9 0.08
YG 2 12.1 5.4
YG 3 38.6 40.9
YG 4 39.2 44.1
YG 5 9.1 8.7
1Treatments included: 1) Revalor- IH on d 1 (80 mg trenbalone acetate (TBA)/8 mg estradiol (E2), noncoated, Merck Animal 
Health DeSoto, KS) and re- implanted with Revalor- 200 on d 101 (200 mg TBA/20 mg E2, noncoated (IH/200), Merck Animal 
Health); 2) Revalor- XH on d 1 (200 mg TBA/20 mg E2, partially coated (XH); Merck Animal Health). Revalor- XH contains 
four uncoated pellets (80 mg TBA and 8 mg E2) for immediate release and six coated pellets (120 mg TBA and 12 mg E2) to 
release approximately 70 to 80 d aft er implanting.
2All numbers are expressed as percentages. Th e yield grade and quality grade values represent the proportion of carcasses within 
each group that received a yield and quality grade.


Evaluation of Two Implant Strategies, Revalor- XH or a Combination Revalor- IH/Revalor- 200 on Heifer Growth Performance and Carcass Characteristics

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Evaluation of Two Implant Strategies, Revalor- XH or a Combination Revalor- IH/Revalor- 200 on Heifer Growth Performance and Carcass Characteristics

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