What Is New With BVDV
Dan Grooms DVM, Ph.D
Michigan State University
College of Veterinary Medicine
Department of Large Animal Clinical Sciences
Topics To Be Covered
Information From NAHMS Dairy 2007BVDV and DeerVaccines and Fetal Protection
Programmed Approach to BVDV Control
Only 31 % of producers were “fairly” knowledgeable = opportunity to educate
Summary
BVDV knowledge - Room for improvement
High percentage of farms vaccinateHigher prevalence of BVDV in larger
herds
BVDV and Deer
Dave Richey: Detroit Free Press
BVDV and Deer
Serological evidence of BVDV infection in white tailed deer
0%
10%
Other states: 2-41% serological prevalence
BVDV and Deer
South Dakota BVDV infected deer with all the
characteristics of PI’s
Experimental Creation of PI Fawns Intranasal with “deer” strain Exposure to PI cattle Survivability appears low
IMPORTANCE?
Wildlife as a Source of Infectious Diseases
White tailed deer - cattle Bovine TB Johne’s disease Leptospirosis Salmonella
– Litchfield, Infantis, and Enteritidis (Nebraska)
Enzootic hemorrhagic disease (EHD) IBR BVDV
Need to be more aware of and manage wildlife – production animal interface
Effectiveness of BVDV Vaccines in Preventing
Fetal Infection
Fetal Protection Against BVDVStudy
VaccineVirus
ChallengeVirus
Vaccinates*
Controls*
Percent Protected
Mclurkin et al 1975 Killed 1 CP 1 12/14 0/5 86%
Harkness et al 1985 Killed 9 CP 1 7/11 0/11 64%
Meyling et al 1987 Killed 1CP 13 NCP 1
2/8 0/5 25%
Cortese et al 1998 MLV 1 NCP 1 10/12 0/10 83%
Brock et al 2001 MLV 1 NCP 2 11/19 0/6 58%
Zimmer et al 2002 Killed CP and NCP 3 NCP 1 7/9 0/15 78%
Zimmer et al 2002 Killed CP and NCP 3 NCP 1 5/15 0/15 33%
Patel et al 2002 Killed CP1 NCP 1 9/11 0/7 81%
Dean et al 2003 MLV 1 NCP 1 25/27 0/13 92%
Fairbanks et al 2004 MLV 1/2 NCP 1 18/18 0/10 100%
Fairbanks et al 2004 MLV 1/2 NCP 2 18/19 0/8 95%
Grooms 2004 Killed 1/2 NCP 1/2 11/15 0/14 73%
Experimental Infections.
What About Natural Exposure via PI’s?
Study Objective
Evaluate the ability of an inactivated BVDV vaccine to provide fetal protection in the face of continuous BVDV challenge in the form of cattle persistently infected with BVDV
Methods 60 Cross Bred Heifers
BVD Virus and Type 1 + 2 Seronegative Randomly assigned to one of two groups
Vaccinated 21 days apart (days 0 and 21) TO1 = Saline TO2 = CattleMaster® GOLD™ FP™ 5-L5
– Inactivated type1/2 BVDV antigen
Given prostaglandin on days 24 and 35 Bred by AI on days 35-44 From pregnant heifers, 15 randomly selected
from from TO1 and TO2
Methods
0 21 35-44 90 190
Day of Gestation ~1 ~50 ~150
100 day exposure
Vaccination Breeding PI Introduced Fetal Harvest
Laboratory Methods BVDV Type 1 and 2 serum virus neutralization
Dams (0, 21, 35, 63, 80, 90, 120, 150, and 190) Fetus (Day 190)
BVDV virus isolation Dams - WBC’s (Days 90, 97, 99 and 101) PI’s – Nasal swabs (Days 90, 120, and 150) Fetal tissues - Spleen, Liver, Lung, Brain (Day 190)
BVDV ELISA Fetal Skin (Day 190)
Genotyping Nested PCR
Results
PI Characterization Nasal Secretions BVDV Titer
(log10 CCID50)
Day of Study
PI # Genotype 90 120 150
9132 y Holstein Heifer
1b 4.1 1.7 4.5
405L3 y Hereford Cow
2 4.1 4.3 4.3
1632 y Holstein Heifer
1b 1.9 2.7 3.5
P171 y Crossbred Steer
2 3.5 3.1 NA
*All PI’s sourced directly from farms
Clinical FindingsAll cows remained clinically healthy 1 control (T01) heifer was diagnosed open
@ day 171 (81 days post challenge or day 130 of gestation) - no fetus recovered All other fetuses remained viable throughout
studyOne PI was euthanized 32 days after
introduction to heifers (P17 – Type 2 steer)One vaccinated heifer (T02) - Twins
BVDV Virus Neutralization
0
2
4
6
8
10
12
14
0 21 90 120 190
Geo
met
ric
Mea
n T
iter
(lo
g 2)
Control Type 1Vaccinates Type 1Control Type 2Vaccinates Type 2
1st Immunization
2nd Immunization
PI’s Introduced
Day 80 Gestation
Day 150Gestation
Virus Isolation - Dams
Virus isolation from dam WBC’s Day 0, 7, 9, 11 after PI introduction 8/15 control heifers (genotype 1 and 2) 3/15 vaccinated heifers (genotype 2 only)
*Significant reduction in BVDV viremia in vaccinated heifers (P<0.05) based on sampling protocol
Virus Isolation - Fetus
Virus isolation from fetal tissues 14/14 controls
– Genotype 1 - 8/14 (57%) – Genotype 2 – 11/14 (79%)
4/15 vaccinates – Genotype 1 - 4/4 (100%)– Genotype 2 - 2/4 (50%)
Skin ELISA 14/14 controls 4/15 vaccinates
*Significant reduction in fetal BVDV infection in vaccinated heifers (P<0.05)
>Multiple viruses found in some fetuses
Conclusion
Vaccination significantly reduced fetal infection with BVDV in a continual exposure model
Protection WAS NOT 100% emphasizing the need for ID and removal of PI’s and biosecurity in addition to vaccination
Fetal infection with multiple viruses can occur = Risk of virus rearrangement
Sahiwal
A Programmed Approach To Controlling BVDV in Dairy
Operations
Dan Grooms DVM, Ph.D
Michigan State University
College of Veterinary Medicine
Department of Large Animal Clinical Sciences
BVDV Control Program
1. Biosecurity
2. Vaccination
3. “Seek and Destroy” PI Cattle
Ohio DairyMarch 95-May 96
0
1
2
3
4
5
6
7
Nu
mb
er
of
Ab
ort
ion
s
3 4 5 6 7 8 9
Month of gestation
BVDV NEG
BVDV POS
Sources of BVDV Exposure
PI’s or Transient Infections Replacements Exhibition Fence line Shared pastures Semen Embryo’s/Recips
Other Species Sheep/goats Camelids Cervidae Insects
Inanimate Fomites Vehicles Equipment People
BVDV Control Program
1. Biosecurity
2. “Seek and Destroy” PI Cattle
3. Vaccination
MOST WANTED
Known carrier of a virulent virus…Persistently infected with BVDV
CONSIDERED ARMED AND EXTREMELY DANGEROUS
IF YOU HAVE ANY INFORMATION CONCERNING THIS PERSON, PLEASE CONTACT YOUR VETERINARIAN
REWARD
BJ
Detection of PI’s
Tests To Detect PI’s
Virus IsolationIPMA
Skin IHC/FA/ELISA
PCRIndividual/Pooled
Blood ELISA
SerologyX
Is BVDV A Problem?
Is BVDV a Problem?
BVDV is Suspected• Poor reproductive performance despite good nutrition and fertility• High calf morbidity/mortality despite good sanitation and nutrition
• Positive screening test• Laboratory confirmation of BVDV infection (virus detection or serology)
BVDV is not Suspected• Good reproductive performance
• Good calf health• Screening tests have been negative
• No laboratory evidence of BVDV infection (virus detection or serology)
BVDV Herd Screening
Herd Screening Tests
Serologyon
SentinelsBulk Tank PCR Pooled PCR
-Unvaccinated calves 6-12 m-Target cohorts
-Both Type 1 and 2
-Looks only at lactating cows-300 cows pools
-Groups of 10-100-Cost effectiveness lost when
prevalence of PI’s is >10%
Negative Positive
Individual TestingContinue Herd Screening
Necropsy
Strategies For Testing Individual Cattle For BVD PI
Dairy HerdsMultiple strategies for testing individual
animals Depending on strategy, testing will occur
over a period of time
Potential Strategies
Test everything at one timeTest new additions (expanding herd)Test new born calvesTest replacementsTest pools followed by individuals
Test all Calves and Adults w/o offspring
Assumption: Calves most likely to be PI’s
Calves serve as sentinels for dams
Pooled PCR
SkinIHC or ELISA
VI/IPMA
NegativePositive
Options: Isolate and Retest Eliminate
Positive
Individual Test
Test Dams
Record Dam as Negative
Positive Negative
If Calf
If Calf
Pregnant cows/heifers
may be carrying PI fetuses.
Must test newborn calves ASAP.
Retain in Herd
I f P o sit ive -B V D V P I
If N eg a tive -R e eva lu a te
If P o sit ive -R e tes t in 2 -3 w e e ks
D a m is n eg a tive
If N eg a tive -B V D V F ree
E a r n o tch E L IS AE a r n o tch P C R
N a sa l sw a b P C R
S ch em e 1 : Te s t a ll a n im a ls o n fa rm a t o n e t im e
T e s t D am
If P o sit ive -B V D V P I
If N eg a tive -R e eva lu a te
If P o sit ive -R e tes t in 2 -3 w e e ks
D a m is n eg a tive
If N eg a tive -B V D V F ree
E a r n o tch E L IS AE a r n o tch P C R
N a sa l S w a b P C R
S ch em e 2 :T es t a ll ca lve s a t b irth fo r 12 m on thsT e s t a ll b u lls
B V D V V a ccin a ted
If P o sit ive -G o to B V D V va ccin a te d sch e m e 1 o r 2
If N eg a tive -H e rd is B V D V free
R e che ck in 12 m on ths
D o B V D V T yp e 1 a nd 2 V N se ro log y on-6 -12 m o n th o ld h e ife rs
-C o w s
N o t V a cc ina te d F o r B V D V
D a iry H e rd
T e s t D am
If P o sit ive -B V D V P I
If N eg a tive -R e eva lu a te
If P o sit ive -R e tes t in 2 -3 w e e ks
D a m is n eg a tive
If N eg a tive -B V D V F ree
E a r n o tch E L IS AE a r n o tch P C R
N a sa l sw a b P C R
S ch em e 1 : Te s t ca lves a t b irthT e s t a ll re p la cem e n ts
T e s t a ll b u llsT e s t a ll co w s w /o ca lves
T e s t D am
If P o sit ive -B V D V P I
If N eg a tive -R e eva lu a te
If P o sit ive -R e tes t in 2 -3 w e e ks
D a m is n eg a tive
If N eg a tive -B V D V F ree
E a r n o tch E L IS AE a r n o tch P C R
N a sa l S w a b P C R
S ch em e 2 :T es t a ll ca lve s a t w ea n ingT e s t a ll o p e n co w s
T e s t a ll b u lls
B V D V V a ccin a ted
If P o sit ive -G o to B V D V va ccin a te d sch e m e 1 o r 2
If N eg a tive -H e rd is B V D V free
R e che ck in 12 m on ths
D o B V D V T yp e 1 a nd 2 V N se ro log y on-6 -12 m o n th o ld h e ife rs
-C o w s
N o t V a cc ina te d F o r B V D V
C o w C a lf H e rd
BVDV Control Program
1. Biosecurity
2. Control Virus Exposure “Seek and Destroy” PI Cattle
3. Vaccination
BVDV-Reproduction- Vaccines Many case/field studies suggest “vaccine
failure/vaccine breaks” w/respect to reproductive disease caused by BVDV.
Experimental studies also show that BVDV vaccines are not 100% efficacious in preventing reproductive disease.
Vaccination is a Tool Not Silver Bullet
My Thoughts on BVDV Vaccines
Believe that MLV vaccines are more effective than killed vaccines Research and biology supports this opinion Killed vaccines are useful and certainly have
a role in BVDV control
My Thoughts on BVDV VaccinesNot a fan of giving MLV BVDV/IBR
vaccines to pregnant cows Two viruses known to cause fetal wastage Ideal timing is prior to breeding Maybe a better time is late in pregnancy
– Dry off– Prebreeding– Low Stress– Improved colostral antibodies
My Thoughts on BVDV VaccinesConceptually, “rotating” vaccines makes
sense, but no science to support benefitsIdea is to broaden antigenic exposure
Bovishield Gold = NADL (1) and (53637 2) Vista = Singer (1) and 125c (2) Titanium = C24V (1) and 296 (2)
Summary
Important and Prevalent virus in the dairy industry
Many clinical manifestationsControl =
Vaccination Biosecurity Seek and destroy PI’s
Case Study
1000 head rapidly expanding dairy Raises no replacements
Consulted because of high incidence of abortions – 10%
Vaccine program Erratic Killed type 1 vaccine
Case Study
Step 1 – What is causing abortion?Submitted fetusesBulk tank milk PCR for BVDVResults
6 fetuses submitted – 3 positive for type 2 BVDV. No other conclusive findings.
Bulk tank positive for BVDV
Case Study
Step 2 – Find PI’sElected to screen entire adult herd for
BVDV 1 PI found in adult herd
Started screening calves at birth ~0.5% incidence over next 12 months
Case StudyStep 3 - Management
Screen all incoming heifers/cows and newborn calves– Incoming = 0.2% incidence– Calves = 0.5% incidence
Initially, vaccinated entire herd with type 1/2 killed vaccine
Switched to MLV type1/2 vaccine prebreeding and at dryoff
Case Study
Results Abortion incidence has dropped to ~2%
Come on Dr. Grooms, get off the ivory tower
kick..give us some good take home stuff…How can we really tell if we’ve got
BVDV?
Top 10 Reasons You Know You Have BVDV
When your carcass compost pile doubles as a sled riding hill for the kids!!
Top 10 Reasons You Know You Have BVDV
When your carcass compost pile doubles as a sled riding hill for the kids!!
When every animal is walking around with strange looking v-shaped notch in their ear.
Top 10 Reasons You Know You Have BVDV
When your carcass compost pile doubles as a sled riding hill for the kids!!
When every animal is walking around with strange looking v-shaped notch in their ear.
When your drug rep say “It can’t be BVDV, you used our vaccine”.
Top 10 Reasons You Know You Have BVDV
When your carcass compost pile doubles as a sled riding hill for the kids!!
When every animal is walking around with strange looking v-shaped notch in their ear.
When your drug rep say “It can’t be BVDV, you used my vaccine”.
When you walk into the calf barn and every calf looks like Michael Jackson!!!!.
Top 10 Reasons You Know You Have BVDV
When your carcass compost pile doubles as a sled riding hill for the kids!!
When every animal is walking around with strange looking v-shaped notch in their ear.
When your drug rep say “It can’t be BVDV, you used my vaccine”.
When you walk into the calf barn and every calf looks like Michael Jackson!!!!.
When you think BVD stands for “Bad Veterinary Disease”
Dr. Grooms DVM BVD
When your pregnancy rate is approaching the approval rating of George W.
Top 10 Reasons You Know You Have BVDV
When your pregnancy rate is approaching the approval rating of Dick Cheney.
When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on...........
Top 10 Reasons You Know You Have BVDV
When your pregnancy rate is approaching the approval rating of Dick Cheney.
When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on...........
When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”,“Tiny”, “Clutzo” and “Nubby”.
Top 10 Reasons You Know You Have BVDV
Will I ever grow up!!
When your pregnancy rate is approaching the approval rating of Dick Cheney.
When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on...........
When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”,“Tiny”, “Clutzo” and “Nubby”.
When you’ve just won a million dollar law suit against the electric company because of “stray voltage”, but herd health still stinks.
Top 10 Reasons You Know You Have BVDV
When your pregnancy rate is approaching the approval rating of Dick Cheney.
When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on...........
When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”,“Tiny”, “Clutzo” and “Nubby”.
When you’ve just won a million dollar law suit against the electric company because of “stray voltage”, but herd health still stinks.
You’ve lost everything but your
Top 10 Reasons You Know You Have BVDV
Dan Grooms DVM PhD
Michigan State University
College of Veterinary Medicine
517-432-1494
Just call me typhoid Bubba!