Hello - I just updated Sunday's case history with his new ACTH & insulin numbers. Also a new body condition photo in his photo album.

Briefly, we have increased his Prascend from 1 tab, to 2 tabs, then to 3 tabs this spring/summer.

We drew blood last Friday (8-12) & his ACTH is now 20.2 which is wonderful.

However his insulin is still not as low as it has been in past years - it was 29 uIU/ml on Friday. In the past it has been in the low to high teens. I feel like the CSU lab reference ranges don't apply, as I believe they are for fasting insulin. In past years my vet had been able to come earlier in the day (late morning or noon) for the blood draws, so that Sunday ate his normal morning meal of hay (8 -9 lbs) & then had blood drawn. Now my vet has been having to come in the mid-afternoon, so Sunday has dined continuously for 7-8 hrs, usually consuming 14 lbs of hay or more before his blood draw. (He does eat out of a slow feeder, I have experimented with various sizes of holes, etc & if I go any smaller he will not eat or will get sores on his lips & nose.)  Blood draw days are now his new favorite days.

Would this raise his insulin? Is it ok for horses to finish eating their hay & have nothing to eat, if blood is drawn within a certain amount of time from when hay ran out?  I am not clear on this. I am clear on the fact that blood draws need to take place at least 4 hrs after breaking a fast of more than 6 hrs, but not clear on if I can feed his normal amount of hay, have him run out & then draw blood within 2-3 hrs of running out of hay.  Should I be concerned about his insulin level of 29? 

Thank you ever so much for your advice!

Rozanne & Sunday
July 02 2019  Larimer County, Colorado
case history:  https://ecir.groups.io/g/CaseHistory/files/Rozanne%20&%20Sunday 
photos:  https://ecir.groups.io/g/CaseHistory/album?id=93586