Hi, welcome to BYC!
I love, love, love pound pups!
It's true, weenies are born hunters. But proper training is key. Learn how to communicate with the dog in a way that is effective
for it. All 3 of my dogs are rescues. And all though I can see they are tempted, they have self control and do what's expected of them.
People told me I couldn't have domestic dogs (non LGD) with goats.... not true, we are doing great after training.... which did take a couple months of persistence before I could trust my dogs.
When it comes to chicks, all running around and peeping... that's a different story for my dogs. They can't be trusted until the chicks are close to 8-10 weeks old.
I tried a young pup (not yet weened) with a bunny once, thinking the killer instincts hadn't set in yet. Instantly the pup tried to chomp the bunny once the bunny hopped. So when you start, make sure you have the pup on a leash. And it's best to introduce after a good tiring play session so some of their energy is tapered off. Young dogs are sponges. I would start with basic command first... come, sit, stay, down. When you do go around the chickens at first, leash on, practice walking around in the same area but don't let the dog FOCUS on the chickens. Keep dog on leash with you as you do chicken chores. But pay attention for the focus factor and break it quickly, the focus usually is a good indicator, eyes locked, ears forward... quick correction then
redirection. You can't just tell a dog what not to do. You have to show them what they can do as well. One of my dogs who would jump on us and nibble fingers out of excitement, we taught her to grab a toy which occupies her mouth and she looks around for something to grab instead of jumping. Now that doesn't stop her skinny tail form whipping us and actually gave my MIL a whelp on her leg through light pants.
I hope things go well for y'all!
Congrats on your new family member!