The stifle is the knee joint - it allows the cow to bend the hind leg and walk.
The stifle joint in a cow is very much like your "knee." It is a complex structure and is subject to many problems. The stifle is found on the cow's hind legs.
A cow. Or, if you want to go into specifics, a dairy cow.
It gives more milk than what it would normally produce for its calf. That's what constitutes a cow for being a dairy cow.
The dairy cow.
Dairy
That all depends on the breed. Are you asking about a dairy cow or a beef cow, and what breed of dairy or beef cow?
Dairy cattle like Holsteins, Brown Swiss and Jerseys.
A dairy cow would die a matter of a few weeks before she even gets to the point where she is deemed "feral." I would see a beef cow becoming feral, yes, but not a dairy cow.
A farm
There's not really an answer... You just call it a cow...
cow
No. The biggest type of bovine is typically the beef cow. There are beef cows around that weight more than a big dairy cow, and that can be upwards of 2000 lbs or more.