The Horse Breeding - Flicka Has a Bad Reaction

Flicka Has Bad Reaction to Rhinovirus Injection

All of the horses got a rhinovirus injection and an Ivermectin worming dose this past Monday.  We have always done this twice a year to the horses that are not in foal.  We have never had any bad reactions in any of the horses.  This time Elvis had terrible diahrrea and seems to still have a stiff neck.  PJ has a knot in her neck at the injection site.  And Flicka turned up Wednesday morning looking like she had had some kind of neurological event in the night.  She could not lift her head above her withers, she could not swing her left front foot further forward then directly below the shoulder.   She carried her head to the right and she did not want to walk forward.   I called the vet and he said that Flicka's symptoms did sound like a reaction to the shot and to give her bute.  I did and she seemed better.  I kept her on restricted movement for a couple of days and it seemed to resolve.  But it was scarey.  She is pregnant.  This cannot be good. 

I did not vaccinate or worm the first mare I bred during her pregnancy.  She had a still-born, deformed foal and we had to put her down.  Everyone said that the foal did not die because we did not vaccinate.  But I did not ever want to have a repeat of that in our little breeding program.  So I vaccinated Prima when she was carrying PJ and decided to vaccinate Flicka this time.  Although I do not do it as often as the equine clinic that did the inseminations recommends.  My horses are not exposed to a lot of other horses and the mares in particular do not go anywhere when they are pregnant. 

But this has caused me to worry about reactions to the vaccine and the Ivermectin.  Flicka has been plagued with neck and back problems since I got her.  I am wondering if the rhino vaccine could be contibuting to her problems.  The symtoms she had this week surely did look like an aggravated version of what she has struggled with all along.   Any insights would be welcomed.