...feed him a few bites by hand.?

There could be many reasons why he won't eat. Stress, health problems, or he could be just taking longer to settle in. Don't overcrowd him so that he's too scared but make him feel welcome and secure. One way to speed the process is to spoil him with caned dog food. they usually can't resist that. when i first got my dog he wasn't eating but i figured out he doesn't eat when i'm around so that may be the case with your new collie. good luck !

Our dog was rescued too and wouldn't eat on her own. For the first few days, she ate out of our hands. Then we started having her eat out of our hand, then we'd put the food on the ground. She started eating it from there. Eventually she ate out of her bowl. It's like she didn't realize the bowl of food was hers. If this doesn't work, definately see a vet.