Seeing as you got her yesterday, I wouldn't be surprised if she doesn't want to eat very much. The change is likely stressful, and stress can dampen an appetite! Also, at 2.5 pounds, she might have just been full! She's very small, and so is her stomach. For reference, my 55 pound dog eats about 1 1/2 cups of food a day, as well as treats and such. And I could probably still cut that back a bit, because sometimes I feel like he gets a little too fluffy even on that ration! What you think is not very much food might be more than enough for a very small dog.
You might also try splitting that 1/2 cup per day over 3 meals instead of 2. Little dogs can't always regulate their blood sugar like bigger dogs, so sometimes its necessary to split up their meals a bit to keep things regular.
If you haven't figured out the food thing in a few days once she's had time to settle in, I would suggest giving your vet a call to discuss.
You might also try splitting that 1/2 cup per day over 3 meals instead of 2. Little dogs can't always regulate their blood sugar like bigger dogs, so sometimes its necessary to split up their meals a bit to keep things regular.
If you haven't figured out the food thing in a few days once she's had time to settle in, I would suggest giving your vet a call to discuss.
