Young kittens between the ages of 3 weeks old and 8 months old will be teething off and on, and will have very strong needs to bite. Just like baby children, kittens are born without teeth, start getting their first baby teeth at about 3-4 weeks old, then they will lose their baby teeth and have their adult teeth come in up until the age of about 8 months old. So the trick here is not to keep them from biting; but rather, to provide them appropriate items to bite. We use heavy-duty plastic drinking straws with our kittens (being careful to cut off any bitten ends and discard the entire straw before it becomes dangerous, as with any toy), and train them from the start that toys and straws are purr-rectly fine to bite, but human body parts are off-limits! If a kitten learns this from the start, there is hardly ever an inappropriate biting behavior as an adult. Some cats start biting out of frustration after they have been de-clawed. Some cats start biting out of misplaced aggression, which usually can be countered by providing the cat a feline playmate, and/or providing them more cat toys, cat furniture, and making their environment more stimulating for them. For a cat with a serious biting problem, often the quickest way to teach them not to bite you is to immediately blow on his face, as soon as you realize he is biting or is about to bite you. Saying "NO!" firmly at the same time reinforces this training. At all times, it is critical that you be thinking and acting on the firm belief that "toys and straws are for biting; human hands are for giving and receiving love".
Don't assume automatically that cats that bite are vicious creatures. You must distinct between play-biting and real aggressive biting. Kittens for example like to play, and sometimes pretty rough. They use their claws and teeth to wrestle with each other. They prepare for catching prey and that’s normal. They usually go unharmed because their fur protects them from serious wounds. However, human skin is a different story, but kittens don't know that.
Problem
When you stroke your kitten it can take it as an invitation to play and clasps your hand and bites. That might hurt a little but is generally nothing to worry about. Some cats make a sport out of leg biting. They jump up on you and dig in. research has show that it’s a sort of unsatisfied hunting and prey instinct and lack of activity.
Solution
• Teach your kitten from an early age that hands are for feeding and stroking and NOT a toy!
• Avoid playing with your bare hands
• Use a fluffy toy or a feather on a string instead
• In case it grabs your hand, draw it away slowly and do NOT punish your cat, it will understand it as an attack and make matters worse
• However if you cat did scratch or hurt you in any way, make a yowling sound and show that you have been hurt, your cat will understand
• If your cat is a "leg biter" try to spend more time playing with it and redirect its attack to a toy. Leave toys lying around so that he can also amuse itself, particular when you keep your cat indoors