Steers going to market don't need to waste energy and lose fat by being distracted by natural urges to reproduce.
"Male cows" castrated before reaching sexual maturity are called steers.
A wether.
A male horse castrated before reaching sexual maturity is called a gelding. A male horse that is sexually mature is called a stallion.
No, males cannot produce sperm before reaching puberty. Sperm production typically begins during puberty, which is the stage of development when sexual maturity is reached.
Ram lamb - if it has been castrated it is known as a wether lamb.
Male wallabies usually obtain sexual maturity at 2 years of age. Females, however, obtain sexual maturity a few months before that.
The main change is physical growth. There is also sexual growth as in reaching sexual maturity.
Only bulls can be castrated, however a few producers have the money to spay their heifers before they enter the feedlot to prevent weight loss when the heifers go into heat. Spaying heifers is a rarity though, and the consequential costs are high. Cows never get spayed. If they can't produce they get sent to slaughter.
Depending on overall condition, at 6 months.
B. Spraying!
Geldings have already been gelded: They are castrated male horses, which means their testes have already been removed. To "geld" is to castrate a male horse like a stallion or colt. Thus, geldings do not need to be castrated because they have already had the surgery done on them earlier in their lives. Horses (more specifically stallions or colts) can be gelded at any age but most are gelded when they are around yearlings or two-year olds, usually right after their testicles drop, or before they reach sexual maturity. However it's not uncommon to have stallions gelded after reaching sexual maturity, especially if they are no longer needed for breeding purposes, or even to calm the horse down, since stallions are more difficult to handle due to hormones than mares or geldings.
It is still called a wether but if it is older than six months of age, in some countries, the castration can only be performed by a veterinarian and under anaesthetic.