i have two labs

Question
i have two lab pups both boys. i too got them from a liter of 12 or 13. the man said they were border colie and black lab, but one of my boys is dark brown. and when they play they get very mean with each other, what can i do about this?. they are very smart pups i mean very smart i have not seen this in two many dogs. what can i do about there fighting.

Answer
The black Lab may have passed on the gene for a chocolate Lab producing the dark brown cross.  I have seen a black Lab produce crosses that looked like yellow Labs.  

Are they really fighting or just playing?  It can be hard to tell.  Here is a link to a picture of a Lab enjoying playing with a Shepherd, http://www.photolocker.net/images/Labman/gretchenandellaplaying.jpg