More advice needed for Babe (old horse with PPID)

Lydia Lawson

Okay it has been a very long time since I gave a report on Babe. If Nancy or Lavinia are reading this I'd like a bit of advice again. She gets a follow up blood test this week. I am trying to remember why they are not supposed to have an overnight fast. Vet said the lab instructions ask for that and he uses Cornell. I draw her myself so I can do it either way but would like to make sure I do it properly to get the best results.

Lydia Lawson

Another quick question on this topic: I have been looking through the files but I am kind of lost :-/ The vet told me to draw the blood into the purple top tubes. Looks like he just did ACTH and glucose last time and not insulin. I can't find in the files if the insulin test can come from the same draw handled the same way. He wants me to put it on ice and bring it right to the clinic so they can spin and freeze it. Is this the proper thing for all three tests or do I need any different tubes etc? Thank you for your help! I want to get the most accurate results I can.

Lavinia Fiscaletti

Hi Lydia,

Hope Babe is doing OK.

The reason we recommend NON-Fasting bloodwork is because horses are not designed to be meal fed - they are continuous, trickle feeders whose digestive tract is meant to have food passing thru constantly. The fasting protocols are a holdover from human testing protocols. When fasted, you get falsely low values. If you pull blood after the first "meal" of the day and there was more than 6 hours between that food (even if only low s/s hay) and the previous food there will be an exaggerated insulin spike.  Plus, the proxies that are used to help with the diagnosis were done on non-fasting ponies so want to approximate the same conditions as closely as possible.

Here is the link to Cornell's website. You can look up all the specific info on how much blood is necessary, what tubes, discount shipping labels. You will want to get ACT/Insulin/Leptin as one test and then the glucose is done separately, from another section of the lab.


Lavinia, Dante, George Too and Peanut
Jan 05, RI
EC Support Team