GSD stool & weight !

Question
Hi! I own a GSD male who's 2yrs 5 months old. He is 26 inches at the withers and thin, i can feel his ribs clearly when i touch his sides.
I feed him ...
morning - brown rice and minced chicken
dinner  - brown rice, 1 or 2 hard boiled eggs, potato n
         other veggies.
and this is supplemented by multi-vitmain, one for his coat and recently digestive enzymes.

Until 2yrs of age he grew up in my sister's house. He urinated n pottied in the front yard and was rarely outside taken on walks (his time 6-9 am and 6-10 pm). He's been livin with me n my GSD bitch since 5 months n wil continue to do so..

My concern is he needs to pass stools several times a day 5 times or more. Half the times it is semi-solid.He is a very active dog n drinks quite a bit, my vet concluded that his romping around n drinking makes him pass stools frequently n makes it loose too. Is it normal ??

And more recently he is having accidents at night, which has never ever happened with him before. He was in my sister's house for 2 weeks after this hapnd and no accidents there. He is back with me and it happened again twice in 10 days. I do walk him before settling for the night. My GSD bitch is potty trained and has no such issues.

Kindly advice...
Thanks for any help.

Answer
I am very concerned about his diet.  It is very difficult to make sure a dog is getting everything it needs and in the proper balance yourself.  I would put him on a commercial dog chow.  Most of them are carefully formulated to provide the complete and balanced diet dogs need.  Most dogs will thrive on them.  In the dog guide program I see thousands of dogs that are doing very well on Pro Plan and nothing else, no additives and supplements.  Get him on a good chow, and the problems should clear up.  

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