Underweight German Shepherd

Question
Hi. I have recently acquired a 5-month old German Shepherd puppy. My concern is that he looks rather thin (I can see his ribs and he weighs around 40 lbs). I feed the puppy regularly once in the morning and once in the evening, and I give him an ample amount of food. However he is very picky and won't eat some of the food I give him. I have tried a variety of food to see which he likes best, including just dry food, dry + wet, raw diet, etc. He will eat once he takes a liking to something, but overall he's just a finicky eater which makes it hard for him to put on weight. Any suggestions? Thank you.

Answer
That is quite common.  I have a manual from large dog guide school that breeds several different breeds.  It has one breed specific statement in it.  ''Note, German Shepherd puppies typically will look very thin throughout puppy hood.''  They don't worry if the ribs show a little.  I would pick a dry food and stick to it, except changing to the adult version.  It slows giving the joints more time to develop.