So my horse got vaccinated on Thursday evening, only vaccines he didn't need teeth floated or anything else. (Vet said he didn't need it done) He was good that evening and all of Friday but when I went to feed Saturday morning he was not interested in his grain which he normally isn't in to much of a hurry but chows down on his alfalfa but this morning he didn't seem like himself. Ate a bit, not much of alfalfa but no grain at all, but then I noticed him trying to reach into the stall next to him trying to get some Prairie hay so I give him some of that and he and cleaned it up but not terrible fast. What I'm wondering is if this could be the after affect of him being vaccinated or does this affect horses? I work at a small animal vet clinic and this does seem to mess with some dogs but this horse is in great health as far as I'm concerned. What I'm wondering is this is a symptom of gastric ulcers but completely out of the blue like this? ( I was also thinking isnt prairie hay much easier or softer on their stomachs? Which made me think even more about ulcers) and this has also kind of been a common not issue but concern as he hasn't been finishing his grain everyday by about 10 am like he used to only does some days. And he isn't lethargic but was just pretty lazy and not really his hardworking, fast working self. Was just curious what y'all were thinking on this. Thanks!

Nothing around here, me included, goes off feed for any reason. Not vaccines. Not ulcer. The choice of grass over alfalfa is the clue for me to say treat for ulcers. 

A friend of mine had his entire herd get terrible sick after vaccinations they all went off feed for a few days... I hate them but I only give one shot at a time. that way I know if one gives a reaction :( 

I bought a 10 year old gelding and the owner told he had a bad reaction when given a 6 way by the vet.  The vet recommended not giving him anymore injections.  He said, with his age he should already be immune to things. 

My Dad died from encephalitis 15 years before that, so I felt strongly about giving it.  I did Eastern/Western/Tetnus and he never had a reaction again.

I have 2 geldings that get a pretty severe fever for 3-4 days after any vaccines. One foundered in 2021 ( Not from vacines) and has completely recovered but he will never be vaccinated again. My mare is 18 this year and won't be getting any, she has had them her whole life. Still debating what I'm going to do for the 5 year old. 

Friends of mine have lost horses after getting their vaccines. I never vaccinate unless it is required for a show or if I am worried about tetanus or rabies exposure.

 I have a mare who swelled/got hives, was lethargic and generally just acted crummy even with dex after vaccines. 

I decided there was no reason to vaccinate her anymore. For the rest of my horses once they have had all the vaccine 1x in their life I quit giving them annually. I've asked my vet about pulling blood and running a titer to check for immunity but she said it wasn't common.

This is common.  We have one horse that always is affected by vaccinations.  We give him some Banamine at the same time as the shots and then have to give him Banamine for 2 days after that.  He will go off of his feed and have some swelling at the injection site.  This year, we had a mare that just got crabby and was a little off of her feed after the vaccinations.  For the mare, we didn't see any affect until the second day.  We gave her some Banamine and she was fine the next day.  We plan accordingly and know that the horses will not be at their best for a few days after the vaccinations.

Every single time. Decided this will be the last year giving all the vaccines after the last bad reaction that lead to a trip to the vet that evening. No more for him. 

I refuse to give 5 or 6 ways anymore. Too many reactions. Missed a show one spring due to a reaction. I give the ranch horses that don't go anywhere a 3way every 2-3 years to get tetanus in them. I have to special order a box of 10 four way (which annoys me) for the ones I haul. If I feel they need west Nile I'll do that separately later if mosquitoes are bad. But I don't do it often. 

Vaccines and Horse Health; Absolutely Necessary? - SecondVet

This was a great read! Dr Schell is amazing and I love to read his thoughts. 

Dr Schell has a lot of great articles. I always like reading something new! Glad you also enjoyed it!