John,
The pictures are painted in an exaggerated form of expression but the point is made. I notice the bone is thin. They exaggerate that to extreme, almost like cartoon characters. Says they were used for draft. Being large, you would expect more bone and leg for draft.
Even the ones that are photos (first photo of a cow, 1868) have less bone in the leg. Interesting. I wonder how accurate the weights are. You don't reckon that would exaggerate that?
Hehe. Look at Cotmore, 4000 pounds and legs like toothpicks. The art of that day is more interesting than the cattle story. :D