MLV Vaccines for Reproduction - Lucky_P

[inyati13]

Vaccines such as Bovi-Shield (Pfizer) for fetal protection cause abortion if the cow or heifer has not been exposed to the MLV vaccine. My question is this; if the cow or heifer was previously vaccinated with a killed virus vaccine, why wouldn't the killed virus vaccine protect the cow or heifer from abortion? If it does not as Bovi-Shield warns on their label, then it raises a question about the effectiveness of a killed virus vaccine for these viruses? If the killed virus vaccines will not protect the cow or heifer from the attenuated virus in the MLV vaccine, then it would not seem to protect the animal from a virus the cow is exposed to by natural pathways. What goes here?

 

[Lucky_P]

It's *possible* that a cow/heifer properly vaccinated with killed viral products *might* not abort if vaccinated with a MLV product.
BUT, neither the manufacturer of the killed or MLV product is going to recommend it. In fact, they'll recommend against it - it's a 'CYA' caution.
We've thought - and most studies I've seen support the fact - that killed viral products don't seem to provide the level of protection - particularly to the fetus/placenta, that vaccination with a MLV product provides. Antibody titers are not the whole story, though they are the most easily-measured indicator of response; but is a titer at a given level(1:32, 1:64, etc.) protective? In many cases, we just don't know. It's difficult to 'measure' cell-mediated immunity.

I've not read labels on any of the killed products recently - but pulled up one of the Triangle products. No label claim about fetal protection - and actually, the label claim is third-tier - 'aids in prevention of disease'. Ideally, you'd want one that can make the claim: 1.Prevents Infection, or, next tier: 2. Prevents Disease.
You've gotta understand what label claims mean - and most folks don't realize what the claims mean; look here: http://beefteam.msu.edu/Resources/Healt ... fault.aspx

 

[tom4018]

It's *possible* that a cow/heifer properly vaccinated with killed viral products *might* not abort if vaccinated with a MLV product.
BUT, neither the manufacturer of the killed or MLV product is going to recommend it. In fact, they'll recommend against it - it's a 'CYA' caution.
We've thought - and most studies I've seen support the fact - that killed viral products don't seem to provide the level of protection - particularly to the fetus/placenta, that vaccination with a MLV product provides. Antibody titers are not the whole story, though they are the most easily-measured indicator of response; but is a titer at a given level(1:32, 1:64, etc.) protective? In many cases, we just don't know. It's difficult to 'measure' cell-mediated immunity.

I've not read labels on any of the killed products recently - but pulled up one of the Triangle products. No label claim about fetal protection - and actually, the label claim is third-tier - 'aids in prevention of disease'. Ideally, you'd want one that can make the claim: 1.Prevents Infection, or, next tier: 2. Prevents Disease.
You've gotta understand what label claims mean - and most folks don't realize what the claims mean; look here: http://beefteam.msu.edu/Resources/Healt ... fault.aspx

Lucky,
Now you got me to rethinking what the local vets suggest. Been using Virashield.

 

[inyati13]

It's *possible* that a cow/heifer properly vaccinated with killed viral products *might* not abort if vaccinated with a MLV product.
BUT, neither the manufacturer of the killed or MLV product is going to recommend it. In fact, they'll recommend against it - it's a 'CYA' caution.
We've thought - and most studies I've seen support the fact - that killed viral products don't seem to provide the level of protection - particularly to the fetus/placenta, that vaccination with a MLV product provides. Antibody titers are not the whole story, though they are the most easily-measured indicator of response; but is a titer at a given level(1:32, 1:64, etc.) protective? In many cases, we just don't know. It's difficult to 'measure' cell-mediated immunity.

I've not read labels on any of the killed products recently - but pulled up one of the Triangle products. No label claim about fetal protection - and actually, the label claim is third-tier - 'aids in prevention of disease'. Ideally, you'd want one that can make the claim: 1.Prevents Infection, or, next tier: 2. Prevents Disease.
You've gotta understand what label claims mean - and most folks don't realize what the claims mean; look here: http://beefteam.msu.edu/Resources/Healt ... fault.aspx

Thanks. You always provide an excellent response. I read my labels multiple times. And always just before I perform an innoculation. I have thought on those words "aids in prevention of disease" and that contirbuted to me going to the Bovi-Shield Gold by Pfizer. I am in the process of getting my small herd onto MLV. It is not easy as I have purchased several bred heifers and none of them have come to me with confidence that they have been exposed to the MLV. Thus, I have to catch them when they are between calves to get them vaccinated. I wish all vaccines came in individual vials like Calf-Guard. I almost always work a single cow or small group at the same time. Yesterday, I vaccinated 3 open heifers and a second calf cow with the Bovi-Shield in preparation for breeding and had to waste one dose on the ground. But that is not as bad as using only one dose out of a 5 dose box and throwing the rest away.

Tidbit: I sold my D3G Cat dozer and hauled it to Danville Friday. The guy who is holding it until it is transported to Illinois has 124 Simmental cows. They are nice animals. Well conditioned. I was impressed with his calves. He told me he never touches them with a needle unless they need treatment. He has a beautiful farm (Danville is some fine land, I had never been there). He is 64 and farmed all his life. I guess he has never had a disease wipe through his herd.

 

[B&M Farms]

Very few people here vaccinate their cows. I guess if you have a closed herd you can get away with it. I still think vaccinations are cheap insurance.

 

[Lucky_P]

B/M
I'm one of those - I have a closed herd, for all intents & purposes - bought a bull in '06; that's the only animal that hasn't been added by AI or natural service birth here since about '96.
No fence-to-fence contact with any other cattle. Nothing leaves & comes back. It's likely that future herdsires will be bred & developed on the farm.
Risk of abortion/respiratory disease due to IBR/BVD/PI3/BRSV is virtually nil here.

I don't vaccinate my adult cows against anything other than Leptospirosis - and a Clostridial booster every 2-3 years.
We do vaccinate steers/non-retained heifers with the full gamut of viral & Pasteurella/Mannheimia vaccines prior to weaning and sale - but not the retained heifers.

 

[Lucky_P]

Now, y'all be sure to understand that what I do with MY herd is not necessarily what I'd recommend to anyone who buys/trades cattle, hauls to shows, or has across-the-fence exposure to other folks' cattle - or have had previous problems with viral pathogens.
Every case needs to be examined individually, and recommendations based upon risk - whether real or perceived.

 

[Fire Sweep Ranch]

OK, so let me ask you a question Lucky (and let me say I really appreciate your input!); Remember we had the heifer abort her calf in the fall just three days after vaccinating with Cattlemaster Gold FP (MLV), and Pfizer said the abortion was not caused by the vaccination and they could not determine the cause? In my heart, I think it WAS caused by the vaccine. My vet stands by the product, but as I think about vaccinating this fall, I waver on whether to use it again or not. We retained the heifer, and she bred back for a September AI calf, do we dare try the same vaccine again or go with something safer? Is she now covered since she was vaccinated in the fall? One loss hits us hard!
We do travel to shows, AND our neighbor does not vaccinate for anything, so I worry about there (they buy replacement cows a few times a year). So we have to vaccinate. I am just a little gun shy now as to what to use, and I trust my vet but wonder how deeply attached he is to Pfizer products....
Thanks for your input

 

[inyati13]

Lucky, if you vaccinate for all the Clostridial organisms (you didn't say if that includes C. tetani) and V5L which is what I understood from your response, you are not making a very big statement of not vaccinating. The only thing you are skipping is the FP viral group.

 

[milkmaid]

inyati13- I think the difference here is the types of pathogens that are being vaccinated for. The clostridial diseases are environmental-origin. They are infectious (cow can get them from soil) but not contagious (they can't be spread cow-to-cow). Having a closed herd or open herd doesn't affect your risk of tetanus, blackleg, enterotoxemia (overeating), etc. It's a good idea to vaccinate for those diseases regardless of your herd status.

On the other hand, the diseases that are contagious (cow-to-cow transmission) should be vaccinated for if there's a possibility of exposure. Lucky has no fence line contact and no animals entering his herd. The risk of exposure to respiratory/reproductive diseases such as IBR, BVD, etc is very low. On the other hand, deer can carry lepto and there must be a significant risk of exposure in his area - which would explain the VL5.

I'm obviously not Lucky but I would guess that is the logic behind the protocol.

 

[inyati13]

OK, so let me ask you a question Lucky (and let me say I really appreciate your input!); Remember we had the heifer abort her calf in the fall just three days after vaccinating with Cattlemaster Gold FP (MLV), and Pfizer said the abortion was not caused by the vaccination and they could not determine the cause? In my heart, I think it WAS caused by the vaccine. My vet stands by the product, but as I think about vaccinating this fall, I waver on whether to use it again or not. We retained the heifer, and she bred back for a September AI calf, do we dare try the same vaccine again or go with something safer? Is she now covered since she was vaccinated in the fall? One loss hits us hard!
We do travel to shows, AND our neighbor does not vaccinate for anything, so I worry about there (they buy replacement cows a few times a year). So we have to vaccinate. I am just a little gun shy now as to what to use, and I trust my vet but wonder how deeply attached he is to Pfizer products....
Thanks for your input

Fire Sweep, I switched from CattleMaster Gold FP 5 to Bovi-Shield Gold FP 5 +L5 because the only MLV in the CattleMaster is BRSV. You probably know that but you have to read the manufactures label very carefully to know how each of the 5 viruses are prepared in the vaccine. Bovi-Shield FP 5 includes all 5 MLV strains. That is why CattleMaster is suppose to be safe for pregnant cows that have not been previously exposed to the vaccine. Again, as you probably know, Bovi_Shield warns against vaccinating preganat cows unless they had been previously exposed to the MLV virus vaccine. That is what prompted the original message that started this thread. I guess you have to trust your vet but I only use the Bovi-Shield on open heifers and on cows when they are between calves. Knock on wood, I have not lost a single calf to anything since I have been at this for the past 3 years.

 

[inyati13]

inyati13- I think the difference here is the types of pathogens that are being vaccinated for. The clostridial diseases are environmental-origin. They are infectious (cow can get them from soil) but not contagious (they can't be spread cow-to-cow). Having a closed herd or open herd doesn't affect your risk of tetanus, blackleg, enterotoxemia (overeating), etc. It's a good idea to vaccinate for those diseases regardless of your herd status.

On the other hand, the diseases that are contagious (cow-to-cow transmission) should be vaccinated for if there's a possibility of exposure. Lucky has no fence line contact and no animals entering his herd. The risk of exposure to respiratory/reproductive diseases such as IBR, BVD, etc is very low. On the other hand, deer can carry lepto and there must be a significant risk of exposure in his area - which would explain the VL5.

I'm obviously not Lucky but I would guess that is the logic behind the protocol.

Thanks. That makes good sense. I had not thought of the Clostridial group as environmental threats. You opened a useful insight. I have a good background in microbiology but I still had not visualized my cows exposure like that. Thanks again.

 

[Lucky_P]

You're spot-on, milkmaid; that's my justification for only doing Lepto and Clostridials.
Had a little run of infertility and a couple of abortions several years back - never confirmed them as L. hardjo-bovis, but everything about the deal suggested it, so we started using a HB vaccine - no problems since. Have done diagnostics on every aborted/stillborn calf (there's not been many) over the past 15 years - provided I find 'em before the buzzards/coyotes clean 'em up - and have not come up with a definitive Dx as to causation.

No, Ron, I don't do the viral vaccines on my cows or heifers - only on steers and heifers we're not retaining; sometimes I wonder if it's worth it, from MY economic perspective - sometimes I get a premium for weaned/vaccinated/bunk-broke calves - but if they're small numbers of non-uniform calves, even when sold in the 'value-added' sale at the local salebarn, I don't see that the buyers are kicking in enough to make up for the extra expense - but, it's the right thing to do for the calf.
I do use MLVs on the sale calves - often while they're still on their non-vaccinated dams. Have experienced nothing to suggest that viral shedding has been a problem - and field trials I've seen with naive cows penned with vaccinated calves showed no abortions or seroconversion of the non-vaccinates, so I don't worry too much about 'em.

FSR - If a mlv vaccine induced the abortion - and the IBR fraction would be the most likely culprit - it should be a fairly easy deal to isolate/detect IBR virus in fetal/placental tissues.
I routinely anticipate, on abortion/stillbirth diagnostic cases, that I'm only going to determine a definitive cause in less than 25% of 'em. Diagnosis rate goes up significantly if I get placenta, but if all I get is the fetus, I'm mainly hoping to 'rule-out' the common causes that the producer and their veterinarian can actually do something about, and if I find an 'answer' on 10% of 'em, I'm feeling lucky.
I'm always a little 'squinchy' about using MLVs in bred cows - but, if they've been properly vaccinated previously with an appropriate MLV product, and you're vaccinating within the approved 'window', you should be OK. But, as inyati indicated, you're probably safer if you use 'em on open heifers or cows prior to breeding - though you'd want to give the MLVs at least a month before you intend to breed 'em.

 

[Fire Sweep Ranch]

FSR - If a mlv vaccine induced the abortion - and the IBR fraction would be the most likely culprit - it should be a fairly easy deal to isolate/detect IBR virus in fetal/placental tissues.
I routinely anticipate, on abortion/stillbirth diagnostic cases, that I'm only going to determine a definitive cause in less than 25% of 'em. Diagnosis rate goes up significantly if I get placenta, but if all I get is the fetus, I'm mainly hoping to 'rule-out' the common causes that the producer and their veterinarian can actually do something about, and if I find an 'answer' on 10% of 'em, I'm feeling lucky.
I'm always a little 'squinchy' about using MLVs in bred cows - but, if they've been properly vaccinated previously with an appropriate MLV product, and you're vaccinating within the approved 'window', you should be OK. But, as inyati indicated, you're probably safer if you use 'em on open heifers or cows prior to breeding - though you'd want to give the MLVs at least a month before you intend to breed 'em.

That is the hard part for us, we calve both spring and fall, and breed when they cycle back. So there is no easy window to vaccinate all of the group. I am not sure what the solution is, other than to make sure our heifers are well vaccinated when we start. We did mail in the fetus, and part of the placenta was with it. So by them ruling out IBR, does that mean the vaccine did not cause the abortion? ALL the girls were open mouthed and salivating 48 hours the vaccine, and I had not seen that kind of reaction before to it. That is why I am leery to vaccinate again with it.

Thanks Ron for input, it is valued and appreciated.

 

[angus9259]

I guess if you have a closed herd you can get away with it.

Last guy I heard say this was complaining that he lost all his calves. Vet said deer can carry.