Infectious Disease Control in Cat Breeding Catteries

Infectious disease is a constant challenge in breeding catteries, particularly where several cats are housed together. Many feline infectious agents can produce subclinical infections, allowing apparently healthy cats to act as persistent sources of infection. Upper respiratory tract disease, including conjunctivitis, is a common problem, with transmission occurring through aerosol and direct contact and therefore being favoured by group housing¹. 

For the practicing veterinarian, effective infection control requires more than identifying and treating clinically affected cats. Group size, stress, quarantine, separation of pregnant queens and protection of kittens all need to be considered as part of routine cattery management. 

Group Size and Stress Matter 

As the number of cats increases, stress also becomes more difficult to control, while managing an infectious disease outbreak becomes increasingly challenging. A cattery housing many cats should ideally maintain smaller groups. 

A group of three or four cats provides a practical balance: the number of animals requiring testing and potentially treatment during an outbreak remains manageable, while stress levels in groups of this size have been described as similar to those of cats living alone². 

This makes group structure an important preventive consideration when advising breeders, particularly where recurrent respiratory disease or other infectious problems are encountered. 

Protecting Pregnant Queens and Kittens^2,3 

The introduction of kittens into a breeding group creates an additional infection-control challenge. Kittens are more prone than adult cats to developing clinical disease and, when infected, may excrete large numbers of infectious agents through secretions and during sneezing. This can increase transmission within the group. 

Stress can also activate subclinical infections. Feline herpesvirus-1 (FHV-1) provides a relevant example; virus excretion can occur within weeks of corticosteroid administration. Reproduction itself can be stressful, with increased blood cortisol concentrations described during lactation. FHV-1-infected queens have also been demonstrated to shed virus 2–10 weeks after parturition. 

Keeping a pregnant queen separated from other cats for at least the final 2–3 weeks of pregnancy can reduce her exposure to infection and consequently reduce the risk of transmission to the offspring. Following parturition, the queen and kittens should remain separate from other cats in the cattery or household. 

This precaution remains relevant even when resident cats show no clinical signs. Apparently healthy cats may carry and excrete FHV-1, Chlamydia species, Mycoplasma species and feline calicivirus (FCV), creating a potential infection risk for unvaccinated kittens. 

Quarantine New and Returning Cats² 

New cats can introduce infectious agents into a cattery, as can resident cats returning after breeding or cat shows. Such cats should be kept in quarantine in a separate room or building for 2–3 weeks. 

Quarantine provides time for clinical signs to emerge, whether due to stress-related reactivation of an existing infection or a newly acquired infection. It also allows appropriate care and testing before the cat joins the group. Testing during quarantine can include assessment for infectious agents and intestinal protozoa. 

However, diagnostic testing has limitations. Certain agents, including Tritrichomonas foetus, may be difficult to detect in infected cats that do not show clinical signs. 

Practical Clinical Approach 

In day-to-day cattery management, infection control should therefore focus on: 

• Maintaining smaller cat groups where practical. 

• Separating pregnant queens during the final 2–3 weeks of pregnancy. 

• Keeping queens with kittens separate after parturition. 

• Quarantining new and returning cats for 2–3 weeks. 

• Recognising that clinically normal cats may still carry infectious agents. 

• Using appropriate testing during quarantine while considering limitations of detection. 

Most infections are managed primarily through husbandry practices designed to reduce stress and minimise transmission. Certain agents, including feline leukaemia virus and feline immunodeficiency virus, can be specifically tested for before mating. 

For veterinarians advising breeders, infection prevention should therefore begin with the organisation of the cattery itself. Appropriate group size, quarantine and separation of vulnerable queens and kittens can reduce opportunities for transmission while making outbreaks more manageable when they occur. 

References 

1. Ström Holst B, Frössling J. The Swedish breeding cat: population description, infectious diseases and reproductive performance evaluated by a questionnaire. Journal of Feline Medicine and Surgery. 2009 Oct;11(10):793-802. https://journals.sagepub.com/doi/pdf/10.1016/j.jfms.2009.01.008 

2. Holst BS. Feline breeding and pregnancy management: what is normal and when to intervene. Journal of feline medicine and surgery. 2022 Mar;24(3):221-31. https://journals.sagepub.com/doi/pdf/10.1177/1098612X221079708 

3. Alekseeva GS, Loshchagina JA, Erofeeva MN, Naidenko SV. Stressed by maternity: Changes of cortisol level in lactating domestic cats. Animals. 2020 May 22;10(5):903. https://www.mdpi.com/2076-2615/10/5/903