My horses are vaccinated for rabies because of the raccoon and possum rabid population. They get Potomac Horse Fever vaccine too along with the 4 in 1 and strangles as I have been there, done that. Your horses and dogs have the perfect living environment and probably don't need half the ones mine get, if any. Look how well the EHV1 vaccine worked with my mares resulting in the loss of two fillies. The Fort Dodge people are supposed to reimburse me for the necropsies, and I have yet to see a check. Some of this preventative stuff is ridiculous.
I gave Kissy the same EHV1 series during Zuri's gestation because Kissy had lost to AI's before 3 months with the previous owner...........I have my doubts on anything the previous owner said, I hope I didn't expose her to something that was unnecessary. Didn't do the series this time around, specifically because of what you went through with your 2 mares, Zuri. I used Fort Dodge also.
I picked up some new breeding Chinese Silkie chickens, day olds and juveniles from a well known breeder back East about 15 years back. They were carrying Laryngo, a really bad respiratory virus with a high mortality rate, that had been established in that breeders flock by vaccinating against it. Those birds shed the virus to my flock. I had to spray all of them and then it was survival of the fittest and deciding whether I wanted to spray the vaccine every year for the duration. After everything was said and done, I lost about 30 % of the flock, breeders, show birds, youngsters, had to disinfect the pens/ feeders/nesting boxes/etc., move them to another area of the property, and dump lime on the previous location.
I quit buying live fowl and went with hatching eggs, expensive and hatch rates were always sketchy as was fertility. That's when I pretty much threw in the towel after 20 years of showing/breeding/hatching and anything that was left ended up as lawn ornaments. It was a major bummer. I had shown in several Nationals, and flew birds back East to be shown out there. Usually I had 4 big show destinations every year, New Mexico, Colorado, Arizona and California.
Zubaz and one of my previous mares, Lady, got strangles, at the horse complex I lived at back then, and both had been getting yearly vaccs for it. It was all about the race horses being brought in every January, I was fortunate that it ran it's course and antibiotics (Combiotic was available then, it was fantastic) kept it from going any further than swelling and discharge under the jaw. I just got to the point where I just
expected it to hit my horses before they were 5, kind of like kids when they used to get mumps back in the day, and then that was the end of it. There was twice in a 5 year period where Thoroughbred mares w/ foals were brought in and all the soon to be weanlings were just dripping discharge from their noses, and under their jaws, almost like a drippy hose.
The only 2 things I really fear with horses is colic and founder: colic all you can do is preventative measures, founder is just hit or miss, both of which can happen when a mare foals, among other things.
With founder, if the coffin bone moves in the hoof, it's all she wrote, no hoof no horse as they say.
Colic.........one roll on the ground and a twist of the intestine, lights out.
If I have to call the vet, things are bad. There's really no middle of the road. If I can't "fix it", I have a horse with one foot in the grave and it's time for the big guns to come out and take a shot at pulling my horse through.