Download Rapid Onset of Protection Against Infectious Bovine Rhinotracheitis

K. Fogarty Fairbanks, J. Campbell, and C. C. L. Chase
Rapid Onset of Protection Against Infectious
Bovine Rhinotracheitis with a Modified-Live Virus
Multivalent Vaccine*
Kris Fogarty Fairbanks, DVMa
Joe Campbell, DVMb
Christopher C. L. Chase, DVM, PhD, DACVMa,c
aRural
Technologies, Inc.
Brookings, SD 57006
bBoehringer
Ingelheim Vetmedica, Inc.
St. Joseph, MO 64506
cDepartment
of Veterinary Science
South Dakota State University
Brookings, SD 57006
C L INI CAL R E L E VANCE
This study provides evidence that subcutaneous vaccination of cattle with a commercially available modified-live virus combination vaccine can help reduce clinical signs associated with infectious bovine rhinotracheitis infections in feedlot
animals vaccinated at the time of arrival. Calves vaccinated 72 or 96 hours before
challenge had reduced clinical signs, lower body temperatures, lower virus titers,
and 39% to 76% greater weight gains compared with nonvaccinated controls.
■ INTRODUCTION
Bovine herpesvirus 1 (BHV-1) is associated
with several disease syndromes in cattle. BHV1 respiratory infections can result in several
clinical manifestations ranging from subclinical to severe infectious bovine rhinotracheitis
(IBR).1 BHV-1 infection in calves and feedlot
cattle can lead to bovine respiratory disease
complex and secondary bacterial infections
that cause significant economic losses to the
livestock industry. Clinical signs include pyrexia, anorexia, conjunctivitis with lacrimal dis*Funding for this project was provided by Boehringer Ingelheim Vetmedica, Inc., St. Joseph, MO.
charge, dyspnea, and nasal discharge.2 BHV-1
infections can also result in infectious pustular
vulvovaginitis3 and abortions4 in adult animals.
Vaccination programs are a routine practice
in US feedlot operations to protect cattle
against disease associated with BHV-1.5 Numerous commercial vaccines for the prevention
of IBR-related respiratory diseases have been
available since the 1950s.6 Current vaccine
protocols recommend vaccination of calves before weaning or commingling to provide maximum protection against IBR. Unfortunately,
many calves are not vaccinated according to
these recommendations, placing them at risk
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Veterinary Therapeutics • Vol. 5, No. 1, Spring 2004
TABLE 1. Incidence of Clinical Signs in Groups of Calves Vaccinated with a Commercial
Modified-Live Virus Multivalent (Bovine Herpesvirus 1, Bovine Viral Diarrhea Virus
1 & 2, Parainfluenza-3, Respiratory Syncytial Virus) Vaccine at Various Intervals Before
Intranasal Challenge with Bovine Herpesvirus 1
Number of Animals Exhibiting Clinical Sign on Given Study Day
Study
Day
Vaccinated
96 hr
Before
Challenge
Vaccinated
72 hr
Before
Challenge
Vaccinated
48 hr
Before
Challenge
Nonvaccinated
Control
Depression
3
4
5
6
7
8
9
10
11
Total*
0
1
1
0
0
0
0
0
0
2 (18%)†
1
0
0
0
0
0
0
0
0
1 (9%)†
3
2
5
0
0
1
2
3
2
8 (73%)
2
1
3
0
0
1
2
3
1
6 (60%)
Respiratory signs
3
4
5
6
7
8
9
10
11
12
13
14
Total*
4
2
3
0
1
1
0
0
0
0
0
0
6 (54%)
3
2
1
0
0
0
0
0
0
0
0
0
5 (45%)
4
4
2
1
4
4
3
2
3
2
1
0
9 (81%)
3
6
3
1
2
5
4
3
5
1
1
0
9 (90%)
Sign
*Total number of calves that exhibited given sign on one or more days.
†Significantly less than percentage for control group (P ≤ .03).
for BHV-1 infection and predisposing them to
secondary bacterial pneumonia.7
The time from vaccination to the onset of
protection can play an important role in subsequent management of newly arrived cattle in
the feedlot. Previous studies have demonstrated
that calves vaccinated 24 to 96 hours before ex-
18
posure are protected against clinical disease
caused by IBR.8–12 Protection against IBR has
occurred as early as 24 hours after vaccination
with an intranasal (IN) vaccine. IN vaccinations have an advantage over parenteral vaccination in the provision of a shorter period from
vaccination to stimulation of active immunity.
K. Fogarty Fairbanks, J. Campbell, and C. C. L. Chase
However, IM vaccinations appear to have similar levels of protection and produce similar levels of both nasal and serum antibodies.4 Protection against BHV-1 challenge has occurred as
early as 48 hours after IM vaccination.
A study was conducted to determine the onset of protection against an IN challenge with
BHV-1 following a SC injection of a commercial modified-live virus (MLV) multivalent
vaccine containing attenuated BHV-1.
■ MATERIALS AND METHODS
Animals
All animal procedures were approved by the
Rural Technologies, Inc. Institutional Animal
Care and Use Committee. Forty-three (33 vaccinates and 10 nonvaccinated controls) Limousin-cross steers, 6 to 8 months of age, weighing approximately 240 kg each, and with
serum neutralization (SN) antibody titers less
than 1:2 to IBR, were acquired for the study.
Calves were weaned on the day of arrival (Day
–16), and each received 10 mg tilmicosin/kg
(Micotil, Elanco Animal Health) SC to prevent secondary bacterial pneumonia during the
acclimation period. The calves were individually weighed, blocked by weight into three
groups of 11 and one group of 10, and allocated within each weight block to four treatment
groups by random drawing. Calves in three of
the treatment groups (n = 11) were vaccinated
96 (Day –4), 72 (Day –3), or 48 (Day –2)
hours before challenge. The final group (n =
10) consisted of nonvaccinated controls.
Animals were commingled throughout the
study except between Days –4 and 0, when
vaccinates were separated from controls. Animals were housed at a research farm near
Brookings, SD, and were fed an age-appropriate diet; water was supplied ad libitum.
Vaccine
A commercial MLV vaccine (Express 5,
Boehringer Ingelheim Vetmedica) containing
BHV-1, bovine viral diarrhea virus 1 and 2,
parainfluenza-3, and bovine respiratory syncytial virus was used for the study. Vaccinates received a single dose (2 ml) of reconstituted vaccine by SC injection in the neck.
Challenge Virus
The Cooper strain of BHV-1 was obtained
from the National Veterinary Service Laboratory,
Ames, IA, and stored at –80˚C until use. For
the challenge, 45 ampules of virus were rapidly
thawed, pooled, and diluted with Eagle’s minimum essential medium to a final volume of 180
ml. Diluted virus was divided into 2-ml aliquots
in snap-cap tubes, placed on ice, and transported to the challenge site. Animals received 5 × 105
tissue culture 50% infective dose (TCID50)/ml of
virus on the day of challenge (Day 0).
Experimental Challenge
All animals were challenged on the same day
(Day 0). Immediately before challenge, a 500ml biohazard bag was placed over the muzzle
of the calf to induce anoxia. When deep
breathing was observed, the bag was removed
and the virus administered using an aerosol
unit (Chromist TLC atomizer; Gelman Sciences) by spraying the challenge virus into the
back of the nares on inspiration. Four ml was
administered to each animal (2 ml/naris). The
biohazard bag was then placed over the muzzle
again until deep breathing was observed.
Clinical Assessments
Personnel performing clinical assessments
were blinded to the treatments. Animals were
observed daily from Days –4 through 14 for
vaccine reactions and clinical signs associated
with IBR infection, including ocular discharge
(lacrimation or conjunctivitis), respiratory
character (rapid short breaths, mild or severe
dyspnea with grunts), coughing, nasal dis-
19
Veterinary Therapeutics • Vol. 5, No. 1, Spring 2004
charge (normal, mild, moderate, or heavy),
nasal lesions, depression, and anorexia. Rectal
temperatures for all animals were monitored
daily from Days 0 through 14.
Calves were individually weighed on Days –1,
14, and 29 to evaluate differences in average daily gain (ADG; (final weight – starting weight)/
(number of days in period).
Blood was collected via jugular venipuncture
on Days 0 and 14 into serum separator tubes for
determination of IBR SN antibodies at Iowa
State University Veterinary Diagnostic Laboratory, Ames, IA, using a standard SN assay.13 A
constant virus (200 TCID50) was incubated
with twofold serial dilutions (1:2–1:4096) of
sera before inoculation of Madin-Darbin bovine
kidney (MDBK) cells in microtiter tissue culture plates. Plates were incubated at 37˚C with
5% carbon dioxide for 5 days before visual assessment of virus induced cytopathic effect.
Nasal secretions (0.5–1 ml) were collected
by aspiration on Days –1, 3, and 6 and tested
for virus isolation, using a standard virus isolation assay. Serial 10-fold dilutions of samples
were made, and each diluted sample was added
in triplicate to MDBK cell monolayers in microtiter tissue culture plates. Samples on culture plates were incubated for 5 days at 37˚C
with 5% carbon dioxide before being evaluated by cytopathic effect and IBR immunofluorescence staining. Samples were considered
negative for IBR virus if no cytopathic effect or
virus-specific fluorescence was observed in inoculated cells after one blind passage.
Statistical Analysis
PROC MIXED procedures of SAS (Version
8.2; SAS Institute) were used for all analyses of
variance and covariance. The PROC FREQ procedure was used for all categoric data analyses.
Differences were considered significant at P ≤ .05.
Body weights were analyzed using a onesided t-test; temperature, serology, and virus
20
isolation were analyzed using an analysis of
variance. In the presence of significant differences among groups, pairwise comparisons
were made between the control group and each
vaccinate group using a one-sided t-test with
the alternative hypothesis that the mean for the
treated group is greater than the mean for the
control group. Pairwise comparisons using
one-sided t-tests were made between individual
vaccinate groups if the means of both of the
treatments in the comparison were significantly greater than the mean for the control group.
Clinical signs were analyzed using the
Cochran-Mantel-Haenszel test. In the presence of significant differences among groups,
the same analysis was used. If the response variable had two categories, a one-sided test with
an α-level of 0.05 was accomplished by evaluating a two-sided test with an α-level of 0.10,
given that the percentage for the control group
is greater than that of the treated group. If
there were more than two categories in the response variable, a two-sided test was used.
■ RESULTS
Clinical Observations
Depression
Mild to moderate depression was observed
on various days between Days 3 and 11 in two
(18%) calves vaccinated 96 hours, one calf
(9%) vaccinated 72 hours, and eight (73%)
calves vaccinated 48 hours before challenge
(Table 1). Depression was observed in six
(60%) nonvaccinated calves. The percentage of
animals vaccinated either 96 or 72 hours before
challenge that became depressed was significantly (P ≤ .03) less than for the nonvaccinated
group. No differences were observed between
the group vaccinated 48 hours before challenge
and the nonvaccinated group.
Nasal Discharge
All animals from all treatment groups had an
K. Fogarty Fairbanks, J. Campbell, and C. C. L. Chase
41.5
Nonvaccinated control
41
Body Temperature (˚C)
Vaccinated 48 hr before challenge
Vaccinated 72 hr before challenge
40.5
Vaccinated 96 hr before challenge
40
39.5
39
38.5
38
0
2
4
6
8
Days after Challenge
10
12
14
Figure 1. Mean body temperature for groups of calves vaccinated with a commercial modified-live virus multivalent (bovine herpesvirus 1, bovine viral diarrhea virus 1 & 2, parainfluenza-3, respiratory syncytial virus) vaccine
at various intervals before intranasal challenge with bovine herpesvirus 1.
increase in nasal discharge after challenge during the 14-day observation period (data not
shown). Only on Day 10 was nasal discharge
significantly (P ≤ .03) less for groups vaccinated either 96 or 72 hours before challenge than
for nonvaccinated calves. There were no significant differences in nasal discharge scores between the group vaccinated 48 hours before
challenge and the nonvaccinated controls.
Ocular Lesions
Nine of 10 (90%) nonvaccinated animals
had moderate to severe lacrimation and conjunctivitis, whereas two (27%) animals vaccinated 96 hours (P = .0007), five (45%) vaccinated 72 hours (P = .05), and six (54%)
vaccinated 48 hours before challenge exhibited
similar clinical signs. These signs commenced
on Day 2 and were resolved by Day 8 for
groups vaccinated either 96 or 72 hours before
challenge, whereas lesions were still present in
two (20%) nonvaccinated calves on Day 14.
Respiratory Character
Changes in respiratory character for all
groups began on Day 3. Abnormal respiration
was seen on Days 3 through 8 in six (54%)
calves vaccinated 96 hours (P < .05 during
Days 8–11) and five (45%) animals vaccinated
72 hours (P < .05 during Days 8–11) before
challenge (Table 1). Nine calves (81%) vaccinated 48 hours before challenge and nine
(90%) nonvaccinated calves displayed abnormal respiration during Days 3 through 14
(Table 1). In addition, nonvaccinated controls
as well as animals vaccinated 48 hours before
challenge showed signs of severe dyspnea during the post-challenge observation period.
21
Veterinary Therapeutics • Vol. 5, No. 1, Spring 2004
TABLE 2. Body Weight Data and Average Daily Gain (ADG) for Groups of Calves
Vaccinated with a Commercial Modified-Live Virus Multivalent (Bovine Rhinotracheitis,
Bovine Viral Diarrhea Virus 1 & 2, Parainfluenza-3, Respiratory Syncytial Virus) Vaccine
at Various Intervals Before Intranasal Challenge with Bovine Herpesvirus 1
Day –1
Day 14
ADG
(kg/day)
Mean
Body
Weight
(kg)
Total
Gain
(kg)
ADG
(kg/day)
Gain
Advantage
Versus
Nonvaccinated
Controls (%)*
15.9
1.06†
273.2
33.0
1.10‡
75.5
255.0
11.6
0.76†
270.3
26.9
0.90
43.1
235.3
244.2
8.9
0.59
261.5
26.2
0.88
39.4
242.2
246.2
4.0
0.26
261.0
18.8
0.63
—
Mean
Body
Weight
(kg)
Mean
Body
Weight
(kg)
Total
Gain
(kg)
Vaccinated
96 hr before
challenge
240.2
256.1
Vaccinated
72 hr before
challenge
243.4
Vaccinated
48 hr before
challenge
Nonvaccinated
controls
Treatment
Group
Day 29
*Calculated using the formula (Vaccinated group gain – Nonvaccinated group gain)/Nonvaccinated group gain × 100.
†Significantly greater than ADG for nonvaccinated group (P ≤ .04).
‡Significantly greater than ADG for nonvaccinated group (P ≤ .004).
Body Temperatures
All nonvaccinated calves had a body temperature reading of 40.6˚C (105˚F) or higher on
one or more days after challenge, whereas
groups vaccinated either 96 or 72 hours before
challenge each had one animal and the group
vaccinated 48 hours before challenge had three
animals with temperatures 40.6˚C or greater on
one or more days after challenge (Figure 1).
Mean body temperature of calves vaccinated 96
or 72 hours before challenge never exceeded
40˚C (104.0˚F) during the 14 days after challenge; peak body temperatures occurred on Day
3 for calves vaccinated 96 hours before challenge
(39.7˚C) and on Day 2 for calves vaccinated 72
hours before challenge (39.9˚C). Mean body
temperature for animals vaccinated 48 hours be-
22
fore challenge reached or exceeded 40˚C on
Days 3 and 4. The mean body temperature in
the nonvaccinated calves peaked at 41˚C
(105.8˚F) on Day 4; however, the mean for this
group was 40˚C or below from Days 4 through
6. Mean body temperature in the nonvaccinated group was significantly (P ≤ .03) higher on
Days 2 through 9 than that for the group vaccinated 96 hours before challenge, on Days 3
through 9 for calves vaccinated 72 hours before
treatment, and on Days 4 through 6 for calves
vaccinated 48 hours before challenge.
Body Weight
ADG for groups vaccinated either 96 or 72
hours before challenge was significantly (P ≤
.04) higher than for the nonvaccinated group
K. Fogarty Fairbanks, J. Campbell, and C. C. L. Chase
5.82 (GM = 6.42) for calves vaccinated 48 hours before challenge,
and 6.00 (GM = 64.00) for nonvaccinated controls.
Average Daily Gain (kg)
1.6
1.4
Vaccinated 96 hr
before challenge
1.2
Vaccinated 72 hr
before challenge
1.0
Vaccinated 48 hr
before challenge
0.8
Nonvaccinated
controls
*
*
Virus Isolation
Virus was isolated from nasal
secretions from all nonvaccinated
calves sampled on Days 3 and 6.
Viral shedding was significantly
(P < .006) reduced in calves vaccinated either 96 or 72 hours before
challenge than in nonvaccinated
controls on Day 6 (Figure 3).
*
0.6
0.4
0.2
0.0
–1
14
29
■ DISCUSSION
This study provided evidence
Figure 2. Average daily gain for groups of calves vaccinated with a com- that a single dose of a commercialmercial modified-live virus multivalent (bovine herpesvirus 1, bovine ly available multivalent MLV vacviral diarrhea virus 1 & 2, parainfluenza-3, respiratory syncytial virus)
cine containing attenuated BHV-1
vaccine at various intervals before intranasal challenge with bovine herpesvirus 1. Asterisks indicate significant ( P ≤ .04 or P ≤ .004) differ- administered SC to calves 72 or 96
ences between the designated vaccinated group and the nonvaccinated hours before challenge with BHVcontrol group.
1 provided significantly (P ≤ .05)
adequate protection against the
on Day 14 (Figure 2, Table 2). ADG to Day 29
development of clinical disease (IBR). Calves
was significantly (P ≤ .004) higher only for the
vaccinated according to either schedule had siggroup vaccinated 96 hours before challenge.
nificantly (P ≤ .05) better weight gains for 14 to
ADG for calves vaccinated 48 hours before
29 days, diminished clinical signs, lower body
challenge was statistically similar to that for
temperatures, and reduced viral shedding.
nonvaccinated calves. Over the 29 days of the
The vaccinated calves in this study gained apstudy, calves vaccinated 96 hours before chalproximately 39% to 76% more weight than the
lenge gained approximately 76% more weight
nonvaccinated controls. Total gains achieved
than did nonvaccinated controls (Table 2).
were less than those previously reported for
calves vaccinated parenterally 48 hours or more
Serology
before exposure11; however, vaccinated animals
All animals had SN titers below 1:2 for IBR
in the earlier study were challenged with BHVon Day 0, and all animals developed titers by
1 via contact, whereas a more severe IN challenge was used in this study.
Day 14. There was no significant difference beIn the present study, calves vaccinated 72 or
tween groups in IBR antibody titers on Day
96 hours before challenge exhibited mild or no
14. The mean log2 titer was 4.91 (geometric
mean [GM] = 30.05) for calves vaccinated 96
clinical signs (depression, respiration, nasal dishours before challenge, 5.36 (GM = 41.17) for
charge) after IN challenge when compared
calves vaccinated 72 hours before challenge,
with nonvaccinated control calves. Results of
Challenge
Study Day
23
Veterinary Therapeutics • Vol. 5, No. 1, Spring 2004
3
2.5
Day 3
Day 6
Log10 titer
2
*
1.5
*
1
0.5
0
Vaccinated
96 hr before
challenge
Vaccinated
72 hr before
challenge
Vaccinated
48 hr before
challenge
Nonvaccinated
controls
Figure 3. Virus (bovine herpesvirus 1) shedding 3 and 6 days after challenge for groups of calves vaccinated with a commercial modified-live
virus multivalent (bovine herpesvirus 1, bovine viral diarrhea virus 1 &
2, parainfluenza-3, respiratory syncytial virus) vaccine at various intervals before intranasal challenge with bovine herpesvirus 1. Asterisks indicate significant (P < .01) differences between the designated vaccinated group and nonvaccinated control group for that sampling day.
this study support findings of earlier studies in
which parenteral vaccinations provided early
protection against clinical signs of IBR.9–11 One
of these studies11 reported that calves were protected against clinical signs as early as 48 hours
after vaccination, using a contact challenge design. In another study,9 IN vaccination administered to calves less than 40 hours before IN
challenge was not effective in reducing clinical
signs associated with IBR. Others10 have reported a reduction in clinical signs 24 hours after IN vaccination in a study using a contact
challenge method.
The mechanisms of early protection against
challenge with BHV-1 are not fully understood. Studies have demonstrated that interferon-gamma (INFγ) may play a role in protection after challenge.14–16 Levels of INFγ were
not monitored in this study; however, SN
antibodies were not present in animals up to
4 days after vaccination, indicating that anti-
24
bodies play a small role in disease
protection soon after vaccination.
Based on the results of this
study, it was concluded that SC
administration of this commercially available MLV vaccine to
nonvaccinated calves at weaning
or at arrival to feed yards will provide significant (P < .05) weight
gain benefits and decreased clinical signs and viral shedding as early as 72 hours before exposure to
other animals with IBR when
calves from different sources are
commingled.
■ ACKNOWLEDGMENTS
The authors would like to thank KyoungJin Yoon, Iowa State University (laboratory
phase), Tanya Triebwasser, Rural Technologies, Inc. (clinical phase), and Maire Loughin, Milliken Associates (statistical analysis)
for their assistance with the study.
■ REFERENCES
1. Kiorpes AL, Bisgard GE, Manohar M, Hernandez A:
Pathophysiologic studies of infectious bovine rhinotracheitis in the Holstein-Friesian calf. Am J Vet Res
39:779–783, 1978.
2. Kapil S, Basaraba, RJ: Infectious bovine rhinotracheitis,
parainfluenza-3 and respiratory coronavirus. Vet Clin
North Am Food Anim Pract 13:455–469, 1997.
3. Kendrick JW, Gillespie JH, McEntee K: Infectious
pustular vulvovaginitis of cattle. Cornell Vet 48:458–
495, 1958.
4. McKercher DC, Crenshaw GL: The virus of infectious bovine rhinotracheitis as a cause of abortion in
cattle. JAVMA 144:136–142, 1964.
5. Bordt DE, Thomas PC, Marshall RF: Early protection against infectious bovine rhinotracheitis with intramuscularly administered vaccine. Proc USAHA 79:
50–60, 1975.
6. Schwarts AJF, York CJ, Zirbel LW, Estella LA: Modification of infectious bovine rhinotracheitis (IBR)
virus in tissue culture and development of a vaccine.
Soc Exp Biol Med 96:453–458, 1957.
7. Yates WA: Review of infectious bovine rhinotracheitis,
shipping fever pneumonia and viral-bacterial syner-
K. Fogarty Fairbanks, J. Campbell, and C. C. L. Chase
8.
9.
10.
11.
12.
gism in respiratory disease of cattle. Can J Comp Med
46:225–263, 1982.
Todd JD: Interferon in nasal secretions and sera of calves
after intranasal administration of a virulent infectious
bovine rhinotracheitis virus: Association of interferon in
nasal secretion with early resistance to challenge with
virulent virus. Infect Immun 5:699–706, 1972.
Todd JD, Volenic FJ, Paton IM: Intranasal vaccination against infectious bovine rhinotracheitis: Studies
on early onset of protection and use of the vaccine in
pregnant cows. JAVMA 159:1270–1274, 1971.
Kucera CJ, Beckenhauer WH: Time required to stimulate protection with intranasal administration of a
temperature-sensitive, infectious bovine rhinotracheitis virus vaccine. Vet Med Small Anim Clin 73:83–
87, 1978.
Sutton ML: Rapid onset of immunity in cattle after
intramuscular injection of a modified-live virus. Vet
Med Small Anim Clin 75:1447–1456, 1980.
Woolums AR, Siger L, Johnson S, et al: Rapid onset
of protection following vaccination of calves with
13.
14.
15.
16.
multivalent vaccines containing modified-live or
modified-live and killed BHV-1 is associated with
virus specific interferon gamma production. Vaccine
21:1158–1164, 2003.
Carbrey EA, Brown LN, Chow TL: Recommended
standard laboratory techniques for diagnosing infectious bovine rhinotracheitis, bovine viral diarrhea and
shipping fever (parainfluenza-3). Proc USAHA 75:
629–648, 1971.
Townsend J, Duffeus WPH, Williams DL: Immune
production of interferon by cultured peripheral blood
mononuclear cells from calves infected with BHV1
and PI3 viruses. Res Vet Sci 45:198–205, 1988.
Ellis JA, Hassard LE, Cortese V: Stimulation of
bovine herpesvirus-1 specific T lymphocyte and antibody responses in cattle following immunization with
a polyvalent vaccine. Agric Pract 15:11–15, 1994.
Lemaire M, Weynants V, Godfroid J, et al: Effects of
bovine herpesvirus type 1 infection in calves with maternal antibodies on immune responses and virus latency. J Clin Microb 38:1885–1894, 2000.
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