Had a conversation this morning about coat colour in Murray Grey’s. Roger Houghton has done quite a lot of work on this so can most likely explain it better. We are based on Angus which would normally be black/black but some also carry the red gene so black/red. To display red both the sire and the dam need to be carriers which is why you see red angus. Putting red aside. The emergence of Murray Greys saw the diluent gene come into play which dilutes the black to various shades of grey and silver. The diluent gene seems quite complicated. Rod Hoare made this little table up which is a simple statistical prediction to aid understanding. The bottom line though is that if you join grey to grey you may or may not, get some black calves depending on the diluent levels in sire and dam.