Commonly castrated animals include horses, cattle, dogs, cats, ferrets, sheep, goats and pigs. However, pretty much any male mammal can be castrated and, if kept as a non-breeding pet, one of the species probably has been.
Humans are animals
Humans are animals.
For most animals, a veterinarian is the only one who can neuter or castrate; this would include small animals like dogs, cats, ferrets and rodents. Horses also should be castrated by a veterinarian. However, particularly in rural settings, it is not uncommon for an experienced farmer or rancher to castrate his own cattle, sheep, goats and sometimes pigs.
Most of animals are killed by humans
Fleas can get on both animals and humans.
they have animals and humans live there.
You cut off it's testicles, the same way you castrate any mammal.
You don't have to castrate them because they are genetically infertile, or cannot produce offspring.
*How do pesticides affect humans and animals?
Animals have special bonds with humans. Humans lack unconditionalness and love unlike animals, especially dogs. There top priority is you, not humans.
Actually the answer is yes. Humans are animals and humans give birth to humans.
The short answer is no. However I would suggest that you want to consider immunizing for tetanus with the slightly older animals.