This article will focus on some recent work on vaccination by Dr. Nathan Erickson and others at the Western College of Veterinary Medicine.
They basically had different calf groups vaccinated with different respiratory virus products in different ways, and measured the results. They solidified some knowledge we have about how we vaccinate our calves, but also posed some questions about how we possibly could vaccinate in the future.
This will open the door for more research and a better understanding on how to get the best vaccination response for our calves’ timing — and the best bang for the buck in the form of intranasal, killed or modified live vaccines, and frequency of administration.
Dr. Erickson and others basically looked at IBR and BRSV vaccines and measured their immune responses.
It is getting to be more and more of a common practice to use multivalent intranasal vaccines at birth or shortly after, and more intranasal vaccines are currently being developed. Close to birth we handle the calves so it is easy to do inoculations, and because it is up the nose, it bypasses the interference by colostrum.
The researchers tried a few combinations and found different responses — the best response came from the intranasal followed up by a killed vaccine at about two months later. Both these vaccines are given in a different location and the killed vaccine has an adjuvant (foreign substance) which stimulates the immune system. The modified live vaccines also replicate and stimulate another part of the immune system and were used in this trial as well.
There is a feeling that even when vaccinating calves at two months of age with a live vaccine there is still interference by colostral antibodies. But by weaning there is a good response.
That leads to the really big question: Can we go with intranasal vaccines at or close to birth and skip the turnout vaccine and just go with the booster shot at weaning?
My thought process was the intranasal vaccines were an add-on shot offering the protection at a really young age while providing immunity that lasts 60 to 75 days. That gets them past the susceptible stage and we can then use the next vaccine pre-weaning (ideally two weeks prior to weaning).
This study should give us faith in intranasal vaccines but also makes us realize timing is very important in vaccinations.
It is good to have different types of vaccines (intranasal, killed or modified live) for the same diseases because they each stimulate the immune system a different way, and when we use one as a booster for the other, we get good results. This is much like the COVID-19 vaccines where studies are finding that an initial priming shot with one vaccine and a booster with another is very effective. (I think that is the route I am going to go with my COVID vaccination.)
If we add in potential different brands of vaccines given to cows and calves, that could stimulate a greater immune response. The whole idea here is getting that herd immunity high in order to protect against disease outbreaks. (But remember that in order to cover things like abortion protection from IBR and BVD, the initial and priming shots must be given from the same vaccine.)
In the future the researchers will try different brands of vaccines. I have always said most of the big companies’ vaccines are very good. They can stimulate each other so using a different vaccine on calves and cows may have merit.
Another question is: Will that pre-weaning shot carry the calves well into the feedlot?
If we knew more of the history of calves coming to the feedlot, we could avoid the redundancy of over-vaccinating in many cases. Currently, that is only possible on direct-purchased cattle or online or through the auction market in load lots where the history can be traced. In mixed cattle lots, many aren’t vaccinated and because doing a traceability and history on each calf in the chute is too time consuming, it doesn’t get done.
Many southern Alberta feedlots even give an IBR booster and I have wondered at times if that is necessary anymore — although I am not sure anyone is gutsy enough to remove it. Virtually none in the north of Alberta or Ontario do that and so I have pondered the million-dollar question: Is it necessary?
There is probably not a lot of harm in over-vaccinating although some vaccines (especially the killed ones with adjuvants) do cause a slight stress response along with the slight needle pain of vaccinating. But the redundancy is a cost for the industry. Even in the days of the true preconditioning very little premium was paid even though on feedlot entry, about all that was necessary were implants and potentially pen identification tags if those are used.
In summary, Dr. Erickson, and others should get producers, veterinarians and any others involved in the health of Canadian calves to seriously think about newer innovative ways to vaccinate our calves and get a better response.
We all know the diseases we need to protect against so it is more about the type of vaccine timing and even changing brands potentially between cows and calves.
In some cases, are we even over-vaccinating or giving a vaccine in the face of maternal antibody that may not give adequate protection?
I have faith that these researchers and others will have more concrete answers in the future. With newer multivalent vaccines appearing on the market and a trend to more intranasal vaccines, more change is on the way.
So stay closely tuned or have your veterinarian stay closely tuned. The only constant is change.