What Is New With BVDV Dan Grooms DVM

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 Ø Information From NAHMS Dairy 2007 Ø BVDV and Deer Ø Vaccines and Fetal Protection Ø Programmed Approach to BVDV Control

Only 31 % of producers were “fairly” knowledgeable = opportunity to educate

Summary Ø BVDV knowledge - Room for improvement Ø High percentage of farms vaccinate Ø Higher prevalence of BVDV in larger herds

BVDV and Deer Dave Richey: Detroit Free Press

BVDV and Deer Ø Serological evidence of BVDV infection in white tailed deer 0% 10% Other states: 2 -41% serological prevalence

BVDV and Deer Ø South Dakota § BVDV infected deer with all the characteristics of PI’s Ø Experimental Creation of PI Fawns § Intranasal with “deer” strain § Exposure to PI cattle § Survivability appears low IMPORTANCE?

Wildlife as a Source of Infectious Diseases Ø 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 BVDV Vaccine Virus Challenge Virus 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 1 CP 1 3 NCP 1 2/8 0/5 25% 0/10 83% Study Cortese et al 1998 Brock et al 2001 Zimmer et al 2002 MLV 1 NCP 1 10/12 Experimental Infections. MLV 1 NCP 2 11/19 0/6 58% Killed CP and NCP 3 NCP 1 7/9 0/15 78% 3 NCP 1 5/15 0/15 33% What About Natural Exposure via PI’s? Killed CP Zimmer et al 2002 and NCP Patel et al 2002 Killed CP 1 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%

Study Objective Ø 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 Ø 60 Cross Bred Heifers § BVD Virus and Type 1 + 2 Seronegative § Randomly assigned to one of two groups Ø Vaccinated 21 days apart (days 0 and 21) § TO 1 = Saline § TO 2 = Cattle. Master® GOLD™ FP™ 5 -L 5 – Inactivated type 1/2 BVDV antigen Ø Given prostaglandin on days 24 and 35 Ø Bred by AI on days 35 -44 Ø From pregnant heifers, 15 randomly selected from TO 1 and TO 2

Methods Vaccination 0 Breeding 21 35 -44 Day of Gestation ~1 PI Introduced Fetal Harvest 90 190 ~50 ~150 100 day exposure

Laboratory Methods Ø BVDV Type 1 and 2 serum virus neutralization § Dams (0, 21, 35, 63, 80, 90, 120, 150, and 190) § Fetus (Day 190) Ø 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) Ø BVDV ELISA § Fetal Skin (Day 190) Ø Genotyping § Nested PCR

Results

PI Characterization Nasal Secretions BVDV Titer (log 10 CCID 50) Day of Study PI # Genotype 90 120 150 913 2 y Holstein Heifer 1 b 4. 1 1. 7 4. 5 405 L 3 y Hereford Cow 2 4. 1 4. 3 163 2 y Holstein Heifer 1 b 1. 9 2. 7 3. 5 P 17 1 y Crossbred Steer 2 3. 5 3. 1 NA *All PI’s sourced directly from farms

Clinical Findings Ø All cows remained clinically healthy Ø 1 control (T 01) heifer was diagnosed open @ day 171 (81 days post challenge or day 130 of gestation) - no fetus recovered § All other fetuses remained viable throughout study Ø One PI was euthanized 32 days after introduction to heifers (P 17 – Type 2 steer) Ø One vaccinated heifer (T 02) - Twins

BVDV Virus Neutralization 1 st Immunization 2 nd Immunization PI’s Introduced Day 80 Gestation Day 150 Gestation

Virus Isolation - Dams Ø 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 Ø 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%) Ø 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 Ø Vaccination significantly reduced fetal infection with BVDV in a continual exposure model Ø Protection WAS NOT 100% emphasizing the need for ID and removal of PI’s and biosecurity in addition to vaccination Ø 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 Dairy March 95 -May 96

Sources of BVDV Exposure Ø PI’s or Transient Infections Ø Other Species § § § Replacements Exhibition Fence line Shared pastures Semen Embryo’s/Recips § § Sheep/goats Camelids Cervidae Insects Ø Inanimate Fomites § Vehicles § Equipment § People

BVDV Control Program 1. Biosecurity 2. “Seek and Destroy” PI Cattle 3. Vaccination

MOST WANTED BJ 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

Detection of PI’s Tests To Detect PI’s Virus Isolation Skin IPMA IHC/FA/ELISA X PCR Individual/Pooled Serology Blood ELISA

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) Is BVDV a Problem? 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 Necropsy Serology on Sentinels Bulk Tank PCR Pooled PCR -Unvaccinated calves 6 -12 m -Groups of 10 -100 -Looks only at lactating cows -Target cohorts -Cost effectiveness lost when -300 cows pools -Both Type 1 and 2 prevalence of PI’s is >10% Negative Continue Herd Screening Positive Individual Testing

Strategies For Testing Individual Cattle For BVD PI

Dairy Herds Ø Multiple strategies for testing individual animals § Depending on strategy, testing will occur over a period of time

Potential Strategies Ø Test everything at one time Ø Test new additions (expanding herd) Ø Test new born calves Ø Test replacements Ø Test pools followed by individuals

Pregnant cows/heifers may be carrying PI fetuses. Must test newborn calves ASAP. Test all Calves and Adults w/o offspring Assumption: Calves most likely to be PI’s Calves serve as sentinels for dams Pooled PCR VI/IPMA Skin IHC or ELISA Retain in Herd Positive Negative Individual Test Options: Isolate and Retest Eliminate If Ca lf If Ca Record Dam as Negative lf Test Dams Positive Negative

BVDV Control Program 1. Biosecurity 2. Control Virus Exposure § “Seek and Destroy” PI Cattle 3. Vaccination

BVDV-Reproduction- Vaccines Ø Many case/field studies suggest “vaccine failure/vaccine breaks” w/respect to reproductive disease caused by BVDV. Ø 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 Ø 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 Vaccines Ø Not 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 Vaccines Ø Conceptually, “rotating” vaccines makes sense, but no science to support benefits Ø Idea is to broaden antigenic exposure § Bovishield Gold = NADL (1) and (53637 2) § Vista = Singer (1) and 125 c (2) § Titanium = C 24 V (1) and 296 (2)

Summary Ø Important and Prevalent virus in the dairy industry Ø Many clinical manifestations Ø Control = § Vaccination § Biosecurity § Seek and destroy PI’s

Case Study Ø 1000 head rapidly expanding dairy § Raises no replacements Ø Consulted because of high incidence of abortions – 10% Ø Vaccine program § Erratic § Killed type 1 vaccine

Case Study Ø Step 1 – What is causing abortion? Ø Submitted fetuses Ø Bulk tank milk PCR for BVDV Ø Results § 6 fetuses submitted – 3 positive for type 2 BVDV. No other conclusive findings. § Bulk tank positive for BVDV

Case Study Ø Step 2 – Find PI’s Ø Elected to screen entire adult herd for BVDV § 1 PI found in adult herd Ø Started screening calves at birth § ~0. 5% incidence over next 12 months

Case Study Ø Step 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 type 1/2 vaccine prebreeding and at dryoff

Case Study Ø 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!!!!. z When you think BVD stands for “Bad Veterinary Disease” Dr. Grooms DVM BVD

Top 10 Reasons You Know You Have BVDV y. When your pregnancy rate is approaching the approval rating of George W.

Top 10 Reasons You Know You Have BVDV y. When your pregnancy rate is approaching the approval rating of Dick Cheney. x. 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 y. When your pregnancy rate is approaching the approval rating of Dick Cheney. x. When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on. . . w When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”, “Tiny”, “Clutzo” and “Nubby”. Will I ever grow up!!

Top 10 Reasons You Know You Have BVDV y. When your pregnancy rate is approaching the approval rating of Dick Cheney. x. When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on. . . w When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”, “Tiny”, “Clutzo” and “Nubby”. v 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 y. When your pregnancy rate is approaching the approval rating of Dick Cheney. x. When your nutritionist blames poor health on your previous nutritionist who blamed it on his/her predecessor who blamed it on. . . w When you have cattle on your farm named “Runt”, “Pipsqueak”, “Shorty”, “Wobbles”, “Tiny”, “Clutzo” and “Nubby”. v When you’ve just won a million dollar law suit against the electric company because of “stray voltage”, but herd health still stinks. u. You’ve lost everything but your

Dan Grooms DVM Ph. D Michigan State University College of Veterinary Medicine 517 -432 -1494 groomsd@cvm. msu. edu

Just call me typhoid Bubba!