We currently have an 8 month old B, about 15 in. She came to us at @ 12 weeks with broken puppy teeth.
She does't take treats. She is a picky eater and will turn down people food. She eats about half a cup 2x per day. She
weighs @ 15 lbs. She has lost @ a half pound in the last couple weeks. I have seen her pick up rocks/pull grass.
We have free fed and tried regular feeding Times and spoon feed when hip bone/ spine begin to show.
The vet had us change the food to the highest protein/fat Puppy food we could find (core grain free puppy formula).
He recommended yogurt "to Settle her stomach". She is negative for Fanconi. We tried cooking, making Gravy,
canned & dry foods.

She doesn't behave like the other basenji we had or others I have seen. She is fearful, quiet, she has
bursts of energy but sleeps often. She laid on the floor in front of the sofa when we got her because
She didn't have the strength to jump up on her own. She just isn't thriving. She is good with other dogs + people.

Does anyone have any ideas on what we could do next?

Did you get her from a breeder and if so have you contacted them?

My first line of defense for a dog that doesn't want to eat is cyproheptadine. It can be miraculous. But frankly, I think your first step is to get her to a university vet immediately for further evaluation. Did they do xrays to make darn sure she doesn't have rocks inside her? That is a really dangerous behavior and you may need to use a basket muzzle on her outside if you cannot remove all rocks from the area.

How are her stools?

Things that come to mind include Immuno-Proliferative Small Intestinal Disease (IPSID). You can read about it at the BCOA site:
http://www.basenji.org/joomla/index.php%3Foption%3Dcom_content%26view%3Dcategory%26layout%3Dblog%26id%3D155%26Itemid%3D292#IPSID

Who did this pup come from? As Debra asked, have they been contacted?

If this dog is eating half a cup 2 x per day and is still losing too much weight….that sounds parasitic in nature (though it could be any number of things). 1.) Vet would be your wisest course of action.....................examining the fecal matter for worms might be an option? Not a sure bet by any means though.

Timesthemyth… duh, don't know why I didn't think immediately also of parasites, which could be. I just assumed they checked but they might not have or checked early before developing. Certainly worth a check and maybe even prophylactic round.

How is this pup doing currently? Any updates?