Your pet is like another child and probably a best friend to your children. Having to figure out who is going to take the family pets when you divorce can be a challenge. Both adults might want to keep the pet, but the children might be distraught over the thought of losing a pet, even if it is only temporary. One thing to remember about this matter is that pets are considered property, so they are handled during the property division process.
There are a host of ways that pets can be handled in this situation. One is that the pet will be taken by one adult and that person will assume all financial responsibility of the animal. The other is that the pet will have a custody agreement much like the children.
Sharing the pet is sometimes a good idea if the children are attached to the pet. In this case, they can bring the animal with them from home to home, so they always have their trusted companion around. If there aren't children in the picture, the animal might spend a week with one person and a week with the other.
If you and your ex share the pet, you will have to determine who will cover expenses. Food might be the responsibility of the person who has the animal at that time. Veterinary bills might be divided down the middle. Agreements about vaccinations, health care and type of food will have to be made. Be sure to include these matters in the paperwork governing the situation so that there aren't any disagreements.