Daily we get questions about situations surrounding the introduction of new pets into homes where other pets currently exist. This seems to be something that is overlooked as a concern for potential disease and behavioral issues of current pets. The most important goal is to protect the pets already in your home. It cannot be underestimated how important it is to keep new pets isolated from existing pets in your home. The new pets can introduce many infections that will put your current pets at risk.
First to remember is that most cat diseases are not a concern for dogs and vice versa. External parasites can be shared amongst dogs and cats. The intestinal parasites of each species are mostly species specific but a few can be transmitted to one another like the tapeworm. Have your pets on flea and tick preventatives before introducing new pets. Take a stool sample in from the new pet to check for intestinal parasites. Have an exam done to reduce the opportunity of lice, skin mites, fungal infections, and other diseases from being introduced to your other pets and yourself.
Second it is important to keep new pets in separate areas away from your current pets until they can be seen by a veterinarian. This prevents potential for diseases to be introduced that would require you to treat the new and current pets in your household. A perfect example is a cute and helpless kitten is brought home and your indoor cat is curious and is allowed to interact with the kitten. A few days later your indoor cat starts sneezing and has mucus in its eyes. The new kitten still does not show any symptoms. Some pet owners do not keep immunizations up to date on indoor cats. That kitten can carry diseases that your indoor cat is susceptible to. Some infections are bacterial and others are viral. The symptoms often present the same but it is difficult to know what caused the disease. When humans show symptoms like sneezing, coughing, nasal drainage, watery eyes our physicians know it could be bacterial, viral, or allergies. Treatment options are varied and some can be difficult to treat.
Something more serious to consider when a new kitten or cat are brought home would be Feline Leukemia(FELV) or Feline Immunodeficiency(FIV) Viruses. These two viruses can be present and they will not show any symptoms. These viruses affect the immune system and are transmitted only through direct contact with body secretions. It can take up to 30 days post exposure for these infections to be detected in a blood test. This can be a challenge since most people want to introduce the new cat to the current cats immediately. This should not be done before testing the new cat for these infections. We have a vaccine for FELV but not one that is readily used for FIV. There are no cures for these infections at this time so once a cat has been infected they remain positive for the duration of their life. A cat can live a normal life with these viruses but they will always be contagious to other cats.
Behaviors can affect the introduction of a new pet into a home. These behaviors can be varied. Some of the behaviors pass quickly and others can become life long. I do not believe there is one way to make these introductions. The most important factor to consider is the safety of the pets and people in the home. If a problem develops it is important to not put yourself at risk by reaching in to separate the pets. Use a loud noise like a kettle being hit by a spoon or compressed air in a can directed at the body of the pets to scare them into scattering. Do not attempt to scold or punish one of the pets since we may do more harm in getting them to accept each other. Pets need to work out their differences without our interference. We are not good at understanding our pets body language and therefore we may punish or scold the wrong pet. Some younger smaller pets are great at instigating the confrontation only to be attacked by the other older or larger pet in the home and we then scold the wrong pet because the smaller younger one appears so helpless. Sounds like something my children would do to get their siblings in trouble. Sometimes it is best to just take a step back and observe the interactions between them. If your pets seem to get along great until you come home each day, then maybe you are interfering more than necessary.
Another frustrating behavior is inappropriate urination that can develop when new pets are introduced. This issue is one of the most common calls we take when dealing with pet behaviors. The first thing to consider is could this pet have a urinary tract infection or some other medical reason for the inappropriate urination. We want to immediately blame the new pet or new environment for the cause but it could be medical. If medical issues are not the cause then we need to quickly seek help to discover the stresses causing this unwanted behavior. The longer this continues the more difficult it can be to stop the problem. This can occur with both dogs and cats.
If you are considering the addition of another pet please make a plan on how to protect your current pets. Nothing is more heart breaking than introducing a new pet and then discovering they had some contagious condition that was passed to your current pets. This happens often within households that do not think through the addition of a new pet. Remember to spay and neuter your pets. Aggression between pets is escalated when intact males or intact females attempt to live together in a home. Pets of the same sex will get along great until both pets reach sexual maturity and then trouble can begin. A pet that is intact is 3 times more likely to bite. This alone is a great reason to make certain to be a responsible pet owner and have your pets spayed or neutered.
Enjoy your Labor Day Weekend and if you find any stray pets while out enjoying the great outdoors make certain to keep them separated from your furry friends until after they are examined by your veterinarian.