Hi Helene,

Considering Rosie's ACTH was too high in Dec 2021 on 0.5 mg, I would say she needs a higher dose of pergolide.  I would try 1mg.  Remember that ACTH is only 1 of the insulin-raising hormones that are elevated with PPID.  We don't know if the other hormones are more elevated and helping drive the high insulin, but pergolide has an effect on all the associated hormones so with a PPID horse increasing pergolide to see if there's an improvement in insulin is always an option.  You want to keep ACTH in the low-middle of the reference range of 2.4-10.2, YEAR ROUND (ie, it's not ok for Rosie's ACTH to go above 5 or 6 pmol/L, even in the fall/seasonal rise).  Test again in early August to make sure it's not climbing (and if it is climbing then you have time to increase the dose).

Also, your hay is probably a little high in ESC and starch than reported since it's an NIR test, so it's good you are soaking it.  And if you are not feeding balanced minerals, a deficiency in Mg in particular can also affect insulin resistance.  We always recommend having minerals balanced to your hay, but if you choose not to do that you could add magnesium oxide.

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Kirsten and Shaku (IR + PPID) - 2019
Kitimat, BC, Canada
ECIR Group Moderator
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