Oh no! I'm so sorry Jackson has taken ill... just read the whole thread now... what a weekend!
As he had a questionable type/amount of food Friday, before the vomiting started, it is most likely that that is what has triggered this attack of pancreatitis. Most likely when this resolves, there is really no reason not to get him back on his regular diet (minus the bully stics) after a week or two of the Rx diet.
This happened when DH started giving Peek a Boo some cheese in the morning (sharing his breakfast!). Thank goodness I happened to get up early and spied the piece of cheese sitting off to the side.
Then Peek threw up foamy stuff. I asked DH, okay, and tell me the absolute truth... how long have you been giving him cheese and how much have you been giving him since this started? He says, Geez, Kathy, we only started off with less than a quater of a slice about a week ago. He wanted more (duh) so I just gave him more. Yesterday he had a whole slice for breakfast! (
)
I asked DH, Hey, Hon, you got your wallet? He says , Yeah, What do you need? I said, Just make sure there's money in it bc we're going to the vet's. Now!. He says, Why? What's wrong? So DH learned all about how a 'little bit' of cheese can trigger pancreatitis. If I hadn't caught him with the cheese that morning, I would never have figured it out so quickly. And getting Peek right to the vet really helped. It ended up costing only $200 and he came home with us with some meds, and diet restrictions of course. Most cases I witnessed working for the vet usually ran in the and minimum 4 days in the hospital on IVs.
He actually relapsed two weeks later, but since then he's been fine. That's been about 7 years ago.
Just wanted to Red Flag you here: Where it says 'not less than 20%...', that's exactly what it means. It's at least 20%, and more likely over or way over 20%. Try to find a food that lists 'Maximum amounts', not minimums.
You may not have to worry about it at all, just go in moderation, and introduce everything one at a time and/or gradually back into his diet, after he has recovered completely, and if this is what your vet tells you (or similar).
Being this is his first attack, and there was good reason or cause for it... I think he'll do okay, you'll just have to pay a little more attention to watching for any recurring symptoms for a while, and really watch what he does get to eat, esp from well intentioned family members. If you have trouble getting them to stop feeding Jackson, it would be much safer to leave him home.
Hoping he gets to come home today! I'm sure he misses you too!