Anecdotally, does PPID and/or pergolide seem to exacerbate vaccine reactions?  My 20yo mare responded very well to recent initiation of pergolide 1mg -- within days she felt tremendously improved under saddle, like her old self; even finished a 6 mile hunter pace feeling like she'd not even worked...life was great until she got her fall flu/rhino vaccine on Monday.  By Monday eve she was depressed (no big deal), Tues morn she couldn't move her neck (stationed her hay & water up on barrels so she could eat; gave 500# Banamine orally), Tues pm could reach to ground but still depressed, and this morning I hopped on and she felt terrible (lethargic, stumbling, stiff, etc; like she feels when her insulin spikes).  She has maintained a normal temperature since the vaccine was given; appetite is good/has not changed; and its the same vaccine & manufacturer we've used for years w/o problem.  My mare has only have one reaction to EWT given years ago back when the Fort Dodge vaccines were the culprit.  I have recheck blood pending at Cornell (ACTH/insulin/lyme multiplex) but it was drawn before the vaccine was given.

I wouldn't say my mare has had overt evidence of immune dysfuction in the past few years, other than decreasing parasite resistance and a broken tooth this past February.  If PPID is unlikely to worsen a vaccine reaction, would the Banamine possibly cause an insulin spike or a temporary worsening of her IR/PPID?  I'm so crestfallen that my mare is back to feel awful after two weeks of blissful riding like old times (bucking & playing, getting run away with...the good old days!)

Kerry in NY
Sept 2014