Why didn’t anyone ever use cows or other bovine as cavalry? The advantage I see is that bovines are naturally inclined to charge and gore, while equines just kick. So if I am charging a group of infantry, a cow seems like it would be more likely to run over someone than a horse.
Plus the winner gets to have a yummy barbecue!
Cows are more valuable as a food source and raw strength than military maneuvers.
Others should come along shortly and milk this thread to better value.
They may not have used cows, but I heard it on authority that they’ve used donkeys. My cite is the famous Sabbath song.
Generals gathering their asses,
just like witches riding asses.
— “War donkeys”
Do horses have more endurance in the gallop than cows?
Oxen were used to pull wagons of supplies probably since the beginning of war and/or domestication of the Ox.
The wiki article on military animals mention that the rhino was rumored to be a war mount, but current opinion is that the poor eyesight and sensitive skin of the rhino would make it a poor choice. Military animal - Wikipedia
Maybe similar problems with Bulls, Buffalo, or Cows exist.
I’d guess that, aside from whatever other issues arise from riding cows around, cattle really aren’t smart enough to be trained to follow commands in the chaos of battle. Once your first member of the cattle-cavalry breaks ranks and runs away, the rest are going to follow.
Is it even possible to use a cow as a steed? The big advantage with horses, as I see it, is that they are intelligent animals and you can train them to do what you want. Domestic cattle, not so much.
ETA: curses, beaten by Jophiel!
…and keep on charging (stampeding) even when you’d rather they stop.
While that may be true, I don’t really see the effort difference in raising horses and cows.
I’ve seen people riding cows.
I mean, I don’t see the difference between cattle and horses. Obviously horses have been bred to be smarter than the average bear, but the ancestors of horses and cows filled the same role in the same environment. I wouldn’t expect any natural intelligence advantage.
And can we keep this from devolving into a joke thread please.
I can’t imagine they are any worse than Rhinos or Elephants in that area, and both of those have been used in war.
Well, cattle have made a difference in the past. Battle of Tondibi.
President Taft thought it was an appropriate mount.
http://i207.photobucket.com/albums/bb236/PWCiccone/TaftonWaterBuffalo.jpg
“Threats all around us! Converging, like a noose! Tightening! Two-head bear people astride battle cattles!”
It’s possible that oxen where one of the very first animals used in organised warfare, used to pull the very earliest wheeled vehicles.
I possible because there’s debate over whether they were pulled by oxen or asses or even if they were actually used as weapons.
This wiki article on the Chariot states that the early chariots were probably pulled by oxen.
The major advantage of cavalry in battle was its ability to outmanuever and flank infantry. The most effective cavalry charges come from the side or the rear. Cattle don’t have the endurance, speed, or surefootedness necessary for manuveouring into an advantageous starting position for a charge.
Sure—you can even train them for show jumping. 
No. You cannot miss this classic.
Seriously, it appears to be the inability to train and direct cows to perform specific functions in the heat of battle. From all accounts they can be trained in rudimentary tasks, but horses still will out in speed, maneuverability and orders.
Modern cattle doesn’t because it has been bred to be fat, produce milk, or whatever. But wild cattle goes on thousand mile migrations and is plenty fast.