Paw paw pressure from heat and animals

I have planted paw paws over the last 2 seasons. It has been very hard (zone 8a central texas)

The 2 oldest lose their leaves in the heat, then releaf, then lose the leaves again before the other deciduous trees shed their leaves. I think they are dead but they releaf in spring.

The newest one (very small) was planted without protection and my sheep ate the leaves. I thought they were not a food source for deer, sheep etc. Is this true?

Wayne, I have had similar problems here in Zone 6B (with some Zone 5 microclimates). I don't know about Paw Paws being unfavored by deer, but my goats sure had not aversion to them. That was my first attempt. My second attempt was a failure due to a flash flood when an upstream dam broke. My third attempt I think I had them in too much sun. Next year will be attempt #4.
Wish me luck.

Planted two paw paw year-old saplings last spring (western NC)... They had plenty of water and were looking beautiful ... up until mid-summer, ... evidently too much sun killed them... Just wondering how I could have prevented this... I put some blue plastic around their base when they started wilting... Perhaps I was too late... Is there a solution for this??? Because I want to try again next year... Thanks...