Should you PCR test new breeding cats without symptoms?

Bringing a new breeding cat home means making decisions about their health before they join your other cats. If they look well and have no symptoms, should PCR testing be part of that process? My view is that a PCR test needs a clear purpose, rather than being something you automatically pay for because a new cat has arrived.

A breeder asked me about this after paying for PCR tests several times. Some had felt worthwhile, while others hadn’t. She wanted to know how to decide when testing was needed, particularly for a new breeding cat without symptoms. The distinction between screening and diagnosis is where I’d start.

What are you trying to find out?

Screening means checking for an infection when a cat isn’t showing signs of illness. Diagnostic testing helps investigate a suspected problem. Those are different reasons for testing, even when the same laboratory method is used.

I see PCR primarily as a diagnostic tool. Rather than starting with “Should I order a PCR panel?”, start with the question you need answered. What infection is being investigated, why is it a concern for this cat, and how would the result affect the next decision? That gives the conversation with your vet a purpose beyond simply having a test done.

Paying for testing doesn’t automatically mean you’ll get a clear explanation of your cat’s health. The result needs to be interpreted in relation to the particular infection and the cat’s circumstances.

A positive result doesn’t always mean illness

Feline calicivirus is one example of why interpretation matters. The European Advisory Board on Cat Diseases’ calicivirus guidance explains that healthy cats can test positive, while a negative PCR result doesn’t rule out infection. Results need to be considered alongside clinical signs. 

That doesn’t make the test useless. It means a result can’t always answer the broader question a breeder has in mind, such as whether a cat is healthy or whether they could introduce an infection to other cats. Before testing, ask your vet what a positive or negative result would actually tell you.

Should you test a new cat without symptoms?

I wouldn’t treat a new arrival as an automatic reason to order PCR testing. But I also wouldn’t turn that into a rule that a cat without symptoms never needs testing. Veterinary guidance includes circumstances where PCR can be used to screen apparently healthy cats, including some testing for feline leukaemia virus in group housing situations. The infection being investigated and the circumstances matter. 

Your vet should guide the decision for your individual cat. A useful question is, “What are we looking for, and what would we do differently depending on the result?” That helps you understand why a test is being recommended and what you’re paying to find out.

I’ve discussed my thoughts on PCR testing in more detail on my Cat Breeding for Beginners podcast. It’s one of the practical breeder questions I cover often in my  New Cat Breeders Club, where I help new and early stage pedigree cat breeders make informed decisions.

For a new breeding cat without symptoms, start with the reason for testing rather than the test itself. Discuss that reason with your vet before deciding what’s appropriate. If you’d like more practical cat breeding content, you can join my email update list for tips, news and offers.