whelping

my bitches coat is thinning on her back and i would like to get her back into tiptop condition ,what can i give her she had pups 7 weeks ago

what materials do i have to use.

I noticed black tarry stool but now its normal diarrhea, she was not eating her food (kibble n bits) so we when to get her some beneful and she ate very well she also drank her water, she is panting lightly are these good signs?