If this same pup displays a corresponding grade of conformation, there should be no problem in selecting the pick of the litter. When evaluating the physical points of your puppies, keep the Breed Standard in mind. Although there are slight variations in head type allowed, you should choose the pup with good width between the ears and at the cheekbones. Choose the puppy with the shorter muzzle and a well-defined stop. I look for good thick ear leather and with a forward set, but I prefer the drop ears.
Experienced breeders know to watch for dental development of their pups throughout their growth.
A slight overbite in a young pup, MAY correct itself in the adults, but a slight underbite almost never does, and usually becomes much worse. In most cases, look for the pup with the longer neck and scapulae which lie well back upon the dorsal bones. Consult the breed standard for specifics on angulation. A bad upright shoulder in a pup never corrects itself in the adult. Body and Hindquarters - the Aussie should have a good amount of width to him.