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Dr. B.
Dr. B., Board Certified Veterinarian
Category: Vet
Satisfied Customers: 22459
Experience:  General practice veterinary surgeon with extensive experience in a wide range of species.
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Is there a clinical reason why some vets insist on starting

Customer Question

Is there a clinical reason why some vets insist on starting the series of puppy vaccinations again if they do not use the same one that the puppy was given for their first vaccinations ?
Is so this seems to make a mockery of breeders giving their puppies first vaccinations.
Submitted: 4 years ago.
Category: Vet
Expert:  Dr. B. replied 4 years ago.

Hello, I am Dr. B, a licensed veterinarian and I would like to help you today.

When a vet suggests restarting a puppy vaccination course, this is done for the medical welfare of the pup and is not done for any other reason. (no matter their opinion on that breeder, etc.). I am happy to discuss this in general terms, but if can provide a bit more specific information we can discuss why Boo's vet may have suggested this in her case.

Can you tell me what vaccines Boo has had?
Specifically, what brand and which viruses covered.
(both of these bits of information should be in her vaccine book from the breeder)

What age was she when she received each vaccine?

Did she have just a single vaccine and is seeing your vet for a second?
If so, how long has it been from the first vaccine (since we only have a 2-4 week window to administer a second vaccination)?

Customer: replied 4 years ago.

She had her first vaccination at 8 weeks of age. She received a combined vaccine Vangard CPV-L and Vanguard DA2Pi which covers her for canine parvovirus, distermper, leptospirosis, adenovirus and parainfluenza.


It will be 4 weeks since her last vaccine on Friday.

Expert:  Dr. B. replied 4 years ago.

Thank you for the further information.

The vaccination that she has had is the proper core vaccine she should receive at 8 weeks of age. Therefore, the only clinical issues that we'd have to consider is whether (1) you are confident that the vaccine was properly maintained (refrigerated/in date/etc.) and administered by the breeder and (2) that the brand of vaccine is the same as what that vet uses (which sounds like it may be the issue at hand).

The reason that we have to use the same vaccination brand for the first & second vaccine has nothing to do with who gave the first; but rather has to do with the development of immunity within the pup. Now as I am sure you are aware, the first vaccine course of the puppy is the only time we give two separate doses. After that first puppy course, booster comprises of one vaccine administered annually.


The reason why we use two doses at this life stage is because we are ‘teaching' an naïve immune system about these viruses/bacteria. That means that we use the first vaccine develops the immunity (get the body making antibodies -the short term immune response) and the second (2-4 weeks later after the body as processed the first one) works to bolster that response (and gets the body to develop memory B cells - the longer lasting immune response that is what we then bolster with annual vaccination).


Now sadly the drug companies who develop vaccinations are not team players (since they are all competing to make money). That means that each company has developed their vaccine using a particular strain of each of the infectious
agents contained in the vaccine (and this would be an asset that they'd not
share with anyone else to prevent competition). And if the strains are not
exactly the same because they are different brands then when we give that second vaccine we will not get the second bolstering of the immune system to get that longer lasting immunity. Instead, we'd just be essentially introducing a ‘new' strain of those viruses/bacteria. So, we'd just the same short term primary response we had with the first vaccine but this time to just slightly different agents. Now there could be some overlap (if the strains are very similar), but without checking antibody titres (which is done via blood sample at some specialist veterinary laboratories) its impossible to know if there is enough to protect Boo if we did use two different brands for her first and second vaccines. And we'd have to appreciate that we could end up in a situation where she hasn't any significant long lasting immunity (and therefore significant risk that she wouldn't be properly protected).

So, as you can see it has no bearing on who gave the first vaccine at all. We'd be in the same boat if another vet had given the first vaccine (or if this vet gave Vangard as her first vaccine, had it go out of stock and he had to change brands). It just hinges on her immune system facing the exact same agents so that we trigger that long lasting immune response. Now in regards XXXXX XXXXX we'd have to do in this situation, there are a few options. As the vet has likely said, you can choose to have the course restarted with the brand they use. In that case, she'd need to restart the course (1st + 2nd vaccine) again. Alternatively, you could contact the breeder to see if they can either vaccinate her, put you in contact with the vet who did (if it was done by a vet) or even dispense a dose of the Vanguard for you to then take to your vet for administering. Otherwise, you could phone your local vet practices to see if anyone carries the Vanguard brand and could thus give her a second vaccine with that same preparation. Finally, you could see if your vet could order the Vanguard vaccine in for you. That said, I do have to warn that most drug companies sell their vaccines by the box and will not let the vets have a single dose (and it'd not be practical for the vet or yourself to have a box of vaccines for the sake of one vaccine) but its worth a try to see if there particular drug company would be flexible.


Finally just to note, Vanguard's data sheet sites ( that we have a 2-4 week window to get that second vaccine into her. After that time frame, we will have a declining primary immunity and in those cases we will restart the course rather then risk inadeqaute immune response. So, if the 4 week period ends on Friday, then we'd need to determine which option to take prior to that day to avoid ending up need to restart anyway.


And just to note, since my initial information request to you, I have had a wee pup present in a similar situation. But in his case since the brand his breeder/their vet used was the same as what we carried, he had his second vaccination today with me with no issue. So, at the end of the day, the reason the vet has suggested restarting the course is nothing personal. Rather it is the demands of a wee puppy immune system



I hope this information is helpful.

If you need any additional information, do not hesitate to ask!

Dr. B.



Ps- I apologize for the strange spacing above, it seems the website doesn't like the internet explorer I am using. :P


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