Be careful when you place the female in the male's cage because often they will fight. To sex an adult male is fairly easy and is often noticeable without close observation. He will be elongated in the back region of his body. When the hamsters are young it can be very difficult to tell the difference. Dirty environments bring on diseases such as respiratory problems and wet tail.
Wet tail is a condition that can be transmitted rapidly from animal to animal and is deadly.
Environmental conditions and diet are factors leading to this disease. Never use cedar bedding for hamsters or any other animal because it can be toxic to them. Use pine or aspen bedding instead. When purchasing a hamster set-up make sure to pick up chew sticks, chew treats and even dog biscuits for the rodent. This will help satisfy their chewing urge and keep their teeth from becoming too long.