Spring vaccines in horses: negative reactions & taking temperatures

horses reacting to vaccinesIt is spring and –sickness– is in the air! At least around here. We have been hit in the house and in the barn. A couple weeks ago two of my kids caught colds that turned nasty and recently (Easter Sunday and Monday) migrated to ear infections. I have charts and rotations of medications that would make any pharmacy proud.

In the barn my horses are also struggling. They had their ‘spring vaccinations’ yesterday and today they are feeling cruddy. They are sore and running fevers. It is clearly the vaccines because three horses were not vaccinated and they are all fine. All the vaccinated horses are running temps between 102.5-103.9.

If you haven’t taught your horse to allow his temperature to be taken easily this is your reminder to go buy a digital thermometer, a jar of Vaseline and get them trained! It is better to do the training before they are grumpy from not feeling well. Did you know that a horses ‘normal’ temperature is actually a range from 99-101? When I was in college we were required to take the horses temperature daily to establish each horses ‘normal’. To do this we would take their temperature daily for several weeks before they left the stall. It is important to take the resting temperature because exercise, stress or excitement can cause an increase.

Have your horses ever had a reaction to spring vaccines? Have you ever taken your horses temperature?


  1. Melisa Ausherman on June 12, 2015 at 3:37 pm

    Just had mine vaccinated and my mare within 24hrs had a 103.9 temp and was acting colicky, she wasnt trying to go down, her gums were white and her head was hanging WAY low. Not my usual toddler mentality into everything Rhu! Immediate shot of banamine and within an hour temp started coming down 1/2 degree at a time. She was back to 99 by 1am, doc said no food or hay, just green grass grazing every hour and half or so for 15 minutes until today. This morning back to knocking chairs over and throwing her hay out in the barn hallway! WHEW!!

    I’ve never had one have a reaction such as that in all my life! SCARY!!

    • Melisa Ausherman on June 12, 2015 at 3:39 pm

      BTW mine were both vaccinated with 6 way and a RABIES, am i starting to see a common factor with the RV vaccine??

  2. Susan Mecredy on June 6, 2015 at 11:19 am

    I am new to ponies and horses but have had to Shetlands for 4 years. Last year the small Shetland had a reaction for 7 days. The vet said it could have been sickness she had hidden before vaccination and the vaccinations put her over the top. This year, I was sure she was 100% healthy, including good temp. I decided to try again – never again. She received 4-way and rabies. In a couple hours she barely was able to stand up. I gave her anti-inflammatory pill and she improved. After being off the pills, it took another few days to get back to being lethargic and not interested in even walking out to pasture. She is so not herself and appears to be not able to see very well. Walks very cautiously thru gates and doors. I am so concerned about her. Any more suggestions?

    • Stacy Westfall on June 6, 2015 at 9:33 pm

      Oh, that is sad! You could have her eyes checked. Vaccines have been implicated in the beginning of moonblindness. Hopefully it goes away on it own.

  3. Laurie on April 9, 2015 at 2:31 pm

    To vaccinate or not to vaccinate, that is the question that is pondering me this year…. No more rabies vaccine as both times my older Morgan did not do well. swelling at injection site and very lethargy with fever. Last year did the five way and both my morgans (5yr old and my 16 yr old ) Both very lethargy and some swelling. Thought maybe I would not vaccinate this year, but vet is highly recommending the four way because of where we live (western & eastern niles). It is sometimes hard to determine what is best for our equines, love them and want to protect them, but is vacines the best way to go????

  4. Jorja Potter on April 9, 2015 at 9:46 am

    Every year my mare gets really lethargic and her neck gets stiff and swollen, I feel so bad for her is there anything I can do to help her after she has had them. Shes usually like this for about two weeks after.

    • Erin Taylor Dresser on January 18, 2019 at 10:23 pm

      Split up the shots. Give her Banamine

  5. Beth on April 8, 2015 at 10:42 pm

    I always write the name of my horses on each shot they get. In case of a bad reaction I have the batch number of the shot. All three of mine did fine this year. I buy and give my shots, a friend had her vet out to give hers and two of the four had fevers and lethargic, so it doesn’t matter if you do it or you have a vet do it, the same issues are going on with human vaccines, to get them or not? I truly believe the problems with vaccines ate the fillers, and I wonder what in the world is the reason for mercury in vaccines.Mercury is not good!!!

  6. Kelsey on April 8, 2015 at 8:25 pm

    Both my donkey and pony had reactions this year. They got rabies and the 4way. Low grade fever, lethargy, stiff and soar neck, hind end muscle quivering.
    Banamine seemed to do the truck.
    I live in northeast Pa.

  7. Alice Weir on April 8, 2015 at 3:58 pm

    Yes,only once. Injection site became swollen and his neck was stiff. My vet marks on the report which shot she gives where, just in case there is a problem.

  8. Marsha on April 8, 2015 at 1:31 pm

    Two of our horses, when young, had an odd thing happen a couple years in a row which we could only relate to their 5 way vaccines. It almost looked like some swelling/inflammation on the trunk (?)of their bodies, just under their coat as the hairs would part and go different directions than normal. Was hoping for an explanation when I saw this post or maybe someone else whose horse has had a similar reaction. Did not take their temps at that time but will this year. Both are fine with the thermometer. Had a friends horse at our barn for a while and he was very nervous about what we where doing back there with that thermometer. 😉

  9. Laurie on April 8, 2015 at 12:03 pm

    When I picked up my horses’ 4 way shots, the vet gave me smaller gauge needles. She said this had been found to help reduce vaccine reactions. Haven’t given the shots yet, but found the information interesting.

  10. Brenda Casteel on April 8, 2015 at 7:39 am

    I have Arabians and they always have a reaction from vaccines. I use bute the night before, the day of and the day after if they are still sore, The Rabies is the worst. I though my old horse was going to die the last time he had Rabies. This year I will give the 4-way but not the rabies. I give the vaccine early in the morning so they can move around all day. I use a little DMSO on vaccine site
    Good Luck

  11. Chantal Arsenault on April 8, 2015 at 7:24 am

    Last week, my ” always hungry and eating” 5 years old QH, Cooper, was no longer able to to lower his neck to eat or drink the day after his shots, also, he would not let me touch the side of his neck where he had the shots, when he tried to lower his neck you could see some of his muscles moving, almost like he was having some spasms. I had to hang up his feed, hay and water. I called the vet and was told to give him some bute. It lasted 2 days before he was back to normal…

  12. RosieB on April 8, 2015 at 6:19 am

    In northern Australia we vaccinate for Hendra (a potentially lethal bat virus transferrable via horses to humans), the last one he had a big reaction and his neck was swollen for a couple of weeks. It is still under trial but there is some doubt now as to the necessity to vaccinate them every 6 months and there are reports of the vaccine
    lowering their immune systems.

  13. Hannah on April 8, 2015 at 6:08 am

    I have seen reactions fairly often but they usually only last a day or two. The illnesses themselves are much much worse so no way would it put me off vaccinating again! Dealing with a high temp and a stiff grumpy horse for a couple of days is definitely preferable to weeks of illness or even loosing your horse altogether!

  14. Diane Walker on April 8, 2015 at 2:02 am

    I have a 25 year old Quarter Horse that for years reacted just like you described yours did after he was vaccinated. My vet started spreading his shots out and this worked much better for him. If the weather is already very warm outside I do give him bute but I try to do shots before it warms up too much.

  15. Robin Brown Woll on April 8, 2015 at 12:30 am

    Stacy…have these horses had these same vaccines in the past and not reacted?

    • Stacy on April 8, 2015 at 9:30 pm

      Yes. Although they did react last year too. This year I asked if any reactions had been reported because I wanted to go whichever route had less reaction (multiple shots, etc). I was told no others had reacted. Different batch? Who knows. Banimine yesterday and time, horses are much better today.

  16. cal on April 7, 2015 at 11:50 pm

    research vaccinosis (in this case equine vaccinosis to be specific.) It will make you rethink how and even why or how often vaccines should really be done. Over vaccination is rampant in humans and our animals and sadly most vets will dismiss this term. If you are a horse owner you at least owe it to your horse to look into this (really research, listen and study) and decide for yourself if you are allowing over vaccination.

  17. Linda Teten-Handwerk on April 7, 2015 at 11:50 pm

    I had a gelding that swelled up like a balloon and couple of mares that were sick and ran temps after vaccines back in the 90’s. After I lost my beloved Rottweiler after routine vaccines I quit vaccines altogether for my animals as well as myself. My horses have all lived long lives well into their 30’s.

    • Christina on November 26, 2015 at 3:20 pm

      I am going to make some comments here. We ALL need to really research what the risks of not vaccinating your horses are in any particular area. I lived in KY and although I knew people who vaccinated their horses, I never did!! I raised foals and rehabilitated starving horses for years and never vaccinated a single one!!! Never had any horse get sick from not vaccinating. I would suggest horses that travel, absolutely need the vacs. Then I moved to Florida and within a few months, I had a horse get encephalitis and die. I consulted a vet in Florida before moving, he said I didn’t need to do anything special for horse, cats or dog. He should have been shot!!!! So it depends, on your area how risky it is.

  18. Anna Scantlan on April 7, 2015 at 11:49 pm

    We had one of our local Equine Centers quarantine themselves because they had two different horses from two different areas show up with the EHV-1 virus. They said that, “patients vaccinated twice a year with the Rhino/Flu vaccine appear to have better protection from developing typical clinical signs of infection and a significantly reduced incidence of shedding high levels of the EHV-1 Virus.” :-/
    Thanks for the information on taking their temperature. Oh my… learning on the fly…

  19. K on April 7, 2015 at 11:19 pm

    My horse had colic and hives with spring vaccinations, it started within a couple of hours. The next year the vet gave him banimine beforehand. No colic, but still got the hives. This year I will spread the vaccinations out, giving the rabies separately and hope for the best.

    • Dee on April 4, 2024 at 6:41 pm

      My Arab was vaccinated Tuesday by my vet not of The horses had a reaction their temperatures were all taken prior it was a six in one my horse had a reaction he’s filled up with fluid he can hardly walk he spiked a fever the next day he wouldn’t eat today he got worse now he’s in the hospital I’m so upset I don’t wanna lose him. The Adema is all in his chest and under his belly and running down his legs the vet took every test and precaution today excellent vet but suggested he go to the hospital I haven’t stopped crying for two days I just came from the hospital he looks pitiful.

      • Stacy Westfall on April 16, 2024 at 9:52 am

        I’m so sorry you are going through this…

  20. maraprotich on April 7, 2015 at 11:06 pm

    Equine vaccines are now reportedly not needed as often as once thought. They contain mercury and there seem to be a large number of horses who are having trouble with them. My mare has bad reactions to vaccines. I will be checking blood for titers prior to any more vaccines that may prove unnecessary. My horses are too precious to risk illness founder or other bad reactions.

  21. Flo on April 7, 2015 at 10:43 pm

    I always establish a base temp and pulse rate on horses that come into my care. Digital and mercury thermometers read different, the digitals are usually lower so you might want to get a base temp on each one. I have had some horses run a fever with vaccinations, some not, it seems to be the rabies vac that causes a reaction. I usually spread my shots out, don’t bombard them with everything at once. I’ve had vets tell me it was ok to give some bute, and some say no. I try not to. My temp for giving bute is 103. That’s for sickness, too. I try to avoid antibiotics and let the fever do it’s job, but if temp gets towards 103, time to intervene. If you give bute, you must give antibiotics.

    • Christina on November 26, 2015 at 3:12 pm

      I think we vaccinate too much too. Can a vaccine work like any other medication where the thing you are vaccinating against becomes immune to it? It seems possible to me if you vaccinate too much. I gave my horse 2 combined shots for encephalitis and west nile and he came down with colic within 2 hrs. I am almost 100% positive that is what caused it. He had pooped 3 times before it happened and once after. Don’t believe he had a blockage, nothing else different. People can have reactions, so why not horses?

  22. Sharon on April 7, 2015 at 10:31 pm

    I quit worming regularly a few years ago and am about to stop vaccinating. Every time my horse has been vaccinated he gets sick. Time to give his immune system a rest and let it do its job. The pendulum is swinging the other way with horse (and pet, in general) health care. We went from not enough to too much and are now learning just how much we need.

  23. Marilee J. Sherman on April 7, 2015 at 9:15 pm

    Yes, it appears we had a major reaction to Vectra Gold vaccination in May of 2013. I’ve been afraid to vaccine since. Not sure what I will try to do this year. Small pony, 14 years old, had received vaccines annually for at least 11 years with no problems. Vectra Gold was new with supposed fewer side effects. He received vaccine May 1st and also acquired a snotty nose with reduced appetite soon after. By May 18 he was in liver failure with high tryglicerides. Recovery has been very slow, with thousands in vet bills and no real answers. Have given up hope on him ever being normal. Yes his temp was checked as soon as he went off feed and is checked at every change in condition. I take temps on any new horses until I feel I have a norm for them. I take them twice a day and take outside temp into consideration. I’ve never really had a horse have issues with taking their temps. I also get resting heart rate on everyone. It is so helpful to know that if they have a problem. If there is a hint of colic or other pain, the heart and respiratory rate really help in evaluating their level of pain, I feel.

  24. pamela on April 7, 2015 at 8:46 pm

    Yes, our little arab got a huge hemorrhoid. Vet said he’s never seen that happen. Since then, he also gets a shot of bute with his shots and he’s been fine.

    • Flo on April 7, 2015 at 10:48 pm

      I read that as the vet mistakenly hit a blood vessel. What’s he gonna say, “oh yeah, I mess up all the time”? Of course he’s “never seen that happen before”. Do you think maybe the reason you’ve never had another problem is because he now gets bute, or because the vet hasn’t messed up again?

  25. Janey on April 7, 2015 at 8:39 pm

    What is the name of the lab that manufactured the vaccine? I am having mine vaccinated tomorrow.

    • Stacy on April 8, 2015 at 9:34 pm

      I didn’t ask as all were already done…

  26. Julie Olson on April 7, 2015 at 8:29 pm

    Vaccinate–NEVER again. My Friesian/Morgan has reacted negatively every year, yet I have been assured it is not the vaccine. He foundered from the rich grass. But I can vaccinate in April, or May, or late June and it is always the same–and it is blamed on the grass. Well no more!! Last year 2 days after his vaccines he was down and I thought I’d never get him up. My other horses had varying reactions to their vaccines-from hives to a large bump at the vaccination sight -to a huge swollen neck. Then there was the horse down. NO I did not call the vet. Vets will never agree it is a vaccine. I called a homeopath. We treated and he is better today, ALMOST year later. But the damage is done and irreversible. I will never vaccinate a well vaccinated horse again. I believe it is un-necessary to heavily vaccinate year after year after year. Initially yes, but there has to be some immunity after years of vaccination. I say check titers and vaccinate accordingly.

    • Christina Garrett on November 26, 2015 at 3:06 pm

      I totally agree. I have a healthy Rocky Mountain horse that is 8 yrs old and I live in Northern Florida, I lost a horse to encephalitis 2 yrs ago. My Rocky Mountain horse came down with colic within 2 hrs of vaccinating. It was the vaccine!!!!!! I called a vet and she said that wasn’t the cause but I know different. He had 4 bowel movements before it happened, no problem with blockage here!! It’s the only thing that was different. Vets anger me, they are as bad as human doctors!!

    • Erin Taylor Dresser on January 18, 2019 at 10:42 pm

      I agree

  27. Linda Lowy on April 7, 2015 at 8:24 pm

    Two years ago most of the horses receiving spring shots had site swelling, others were stiff. Last year, no problems. Haven’t given the shots yet this year.

  28. Kim VanDrisse on April 7, 2015 at 8:14 pm

    I’ve had issues with a certain brand of vaccine leaving my horses sore and with obvious lumps… I don’t use that brand anymore. I also now give a tab of bute the day of and the day after vaccinations and rub the area around where the vaccine was given with DMSO for a few days.

  29. marsha tipton on April 7, 2015 at 8:03 pm

    I lost a horse to a 5way shot, he foundered and never recovered

    • Julie Olson on April 7, 2015 at 8:30 pm

      So sorry for your loss. I has had similar experience. It can be a bad deal to vaccinate every year.

    • Jenny Northcott on April 7, 2015 at 10:25 pm

      I have never heard of that happening! That must make you worry about vaccinating in the future. Do you still vaccinate? What did your vet recommend? Did your vet discuss this as a possible risk prior to vaccinating? Thanks for any info you can share!

      • Stacy on April 8, 2015 at 9:34 pm

        I still vaccinate, with our travel schedule we are high risk. I did quiz the vet and I wonder if bute or banimine before hand would reduce the reaction. Reactions are usually blamed on which ‘batch’ you receive. Our older horses reacted less than our younger ones. Coincidence?

  30. Jen on April 7, 2015 at 7:59 pm

    Hi Stacy. My two horses receives their spring vaccinations yesterday and I did not notice any reactions at the time. Today when I got to the barn my 4 year old gelding seemed a bit lethargic but brightened up when I gave him an apple. My 20 year old mare seemed like her everyday self. Thank you for posting this article, I didn’t even think to check temperatures but I will now. I did check for heat and swelling at the injection site and for any bumps or hives.

  31. barbkeith on April 7, 2015 at 7:55 pm

    I’m not sure if mine was a reaction or not but exactly 2 weeks after being vaccinated, my healthy 26 year old horse was found with his back end paralysed. I was too devastated over losing him at the time to really investigate it.

    • Jackie on April 8, 2015 at 10:18 am


  32. Loretta Fern King on April 7, 2015 at 7:35 pm

    where are the westfalls now ? You made it sound like you’re at your barn again ! ( Is Whizards Maggie Mae still yours ?

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