need help with a picky eater

[crispit1023]

I was previously feeding my BP f/t rats from Petsmart, until a recent Salmonella incident that forced them to dispose of their entire stock. I had been wanting to start ordering them online, so I ordered some from Layne Labs and Big Cheese Rodent Factory, but he won't eat any of them. There have been no changes in husbandry and he RARELY doesn't eat for me. I have attempted "scenting" the new rats with some Petsmart ones, but that hasn't worked. He hasn't eaten in over a month now, so I broke down and gave him one from Petsmart today, which he obviously ate. However, I would really like to switch him over to the new ones. Any advice on how to do this? Also, I know they can go awhile without eating, but at what point should I be concerned if I know it's just because he's being picky? Thanks so much.

[albinos_rule]

I wouldn't worry a lot until you can visibly tell he is losing a lot of weight, or even better yet get a scale that measures in grams, and check his weight periodically.