New cats must be quarantined. The requirements for isolated places are:
Old cats will never get in, which will affect their original way of life to a minimum. The isolated place can be a room at home (there must be a lockable door). If there is no separate room, or the old cat is used to sleeping in the bedroom with you, it can be isolated in a sealed balcony or bathroom (a door is also needed). If only the toilet is available, and the old cat's toilet is also in the bathroom, you can move his toilet to a new location. If possible, do this preparatory work 1 to 2 weeks in advance. In short, the smaller the change to the old cat's original lifestyle, the better for him to adapt to the arrival of the new cat. If the above conditions are not met (to be honest, I don't think it is really necessary to add another cat if there is no second door except the main door), you can use a larger cage cover as an isolation facility, but it is best to know that the newly raised cat has no diseases.
The requirement for isolated places is that there is nothing dangerous or harmful to cats. The place is not very big, but it is easy to adapt to small. There should be a litter box in the isolated place, a nest where cats can hide and rest (not too complicated) and clear water. It is best for the host to send food in regularly, and then take it out after eating, instead of always putting it in it. This will help the new cat quickly establish the connection between the new owner and the food, as well as the corresponding trust and feelings. After all the preparations (material and psychological) are completed, you can take the new cat home.
Second, after bringing a new cat home.
Step 1: Take the new cat home, put it directly in an isolated place, don't stay any longer, come out immediately and close the door.
Then say hello to the old cat according to the original family procedure. Put the new cat's bag or cage at home (don't put it directly in front of the old cat) and observe the old cat's reaction. Some cats will be nervous and even attack the cage (prepare for a protracted war), some will growl, keep running away and come back (typical), and some will be curious and excited (optimistic prospect). Observe carefully until the old cat completely loses interest in the cage and then take it away. Spend more time with the old cat and don't go to see the new cat for the time being. He needs some time to get used to the environment in the quarantine area. At least 1 hour later, you can bring something to eat to see the new cat. If this is your first contact with this cat, don't try to get close to it, talk to it gently and wait for it to get close to you. Don't stay too long, 30 minutes to 1 hour is enough. You can see him several times a day, each time 1 hour or so. If you pet a new cat, you'd better wash your hands before approaching an old cat. Even so, the old cat may still be confused by your strange smell, so ha you. Pay attention to how much time the old cat spends sitting outside the isolation room or smelling there every day. Only when the old cat is not hostile to the cage with the new cat, the smell of the new cat on you and the door of the quarantine area can you enter the second step.
What needs to be noted in this step is that it must be better for the old cat. Play with him more, talk with him, feed him something delicious and spoil him. Make sure he feels that he is at home and his position in your heart is not threatened.
The first step that can be changed is that after the new cat is familiar with the quarantine area and has established a basic trust in people, it can be released for a short time every day to familiarize it with the environment in other parts of the family. At this time, it is necessary to isolate the old cat. It is best not to isolate the new cat. It is best to have someone to accompany him to avoid him being too nervous. Then send the new cat back to the isolation room, let the old cat out and observe its behavior.
Step 2: Limit contact.
Let the new cat have limited contact with the old cat. You can see each other through the glass door, but you can't touch each other. You can also open a small slit in the door of the isolation area, let them touch their noses and wave their claws, but don't touch each other too much. If there is no one at home during the day, make sure that all the settings can achieve the purpose of limiting contact before going out, but no one can break through the obstacle. If there is enough space under the door of the isolation area for the cat's claws to expand and contract, then the first step and the second step are actually carried out at the same time.
In the meantime, if you greet you with a new cat and an old cat at the same time, you must respond to the old cat first. The reason is as above. The new cat will understand this.
When the new cat and the old cat are relatively calm in this situation, and rarely yell or yell at each other, they can enter the third step.
Step 3: Full contact.
Open the door of the quarantine area and let the new cat meet the old cat. Not deliberately introduced. Open the door when the old cat is not near the quarantine area. Let them meet "inadvertently" instead of "formally". Watch their reaction closely. Maybe they will still chase each other, but as long as there is no fierce fighting, they will continue to observe. When fighting, you can say "don't fight" sharply or use water spray to separate. Don't separate fighting cats with your hands, it's easy to hurt people. In addition, when cats fight, it always sounds more serious than the actual situation, so don't worry too much. Trimming the cat's nails often can reduce the degree of injury. If the fight is fierce or you fight together soon after separation, go back to the second step for a while and then enter the third step.
It is suggested that this step, under the supervision of someone, start with full contact once a day, for a short time, gradually to many times, for a short time, for a long time, and finally for a whole day. The first all-day contact is best on weekends, which is convenient for the owner to observe and intervene. Don't leave them at home all day until you are confident that they can live in peace.