[Hawkblack]

Coat
Outer coat is straight, coarse, dense, of medium length and lying flat. Undercoat should be present on neck and thighs, but the amount is influenced by climatic conditions. Undercoat should not show through outer coat. The coat is shortest on head, ears and legs, longest on breeching. The Rottweiler is to be exhibited in the natural condition with no trimming. Fault--Wavy coat. Serious Faults--Open, excessively short, or curly coat; total lack of undercoat; any trimming that alters the length of the natural coat. Disqualification--Long coat.

What you may be seeing is the undercoat showing through. It also could change as this is a a puppy that still has puppy coat. Enjoy your puppy let them grow and all will be good.

As for the puppy with the tan on ears this usually like the neck goes away. it is usually puppy fur. Most of my puppies that I have raised have had this on their ears. Sometimes as the puppy coat gets ready to blow or shed out it can look red tint.