The Inclusion of Cat Dens in a Population of Shelter Cats and Their Effect on Upper Respiratory Infection and Length of Stay

Introduction: Feline upper respiratory infection (URI) is common in high-density populations, such as those in animal shelters. URI treatment delays time to adoption, often resulting in welfare concerns and significant expenditure of shelter labor, medication, and foster care resources. The purpose of this pragmatic, randomized controlled trial was to determine if the presence of enrichment via a consistent hiding den (i.e. feral den) throughout a cat’s time in shelter reduces their URI incidence and time to adoption. Methods: Cats enrolled in this study were assigned either a den or no den and tracked from shelter intake to outcome (i.e. adoption, return to owner, and euthanasia). Cats in both groups received the usual standard of care and were monitored daily by shelter staff. The impact of a cat den on both URI occurrence and length of stay (LOS) was modeled using logistic regression and competing risks regression models, respectively. A mediation analysis was also performed to assess the den’s effect on LOS through URI occurrence. Results: The impact of a cat den on LOS was mediated through a decreased probability of URI. Participant cats assigned to the den group had a 33.7% lower incidence of URI diagnosis compared to those in the control group. For cats who developed URI, the presence of a den did not significantly affect the severity of disease when compared to the control group. Cats diagnosed with URI while in shelter were 27.2% less likely to be adopted at any given time when compared to cats with no URI, regardless of den presence. Conclusion: Cats who did not experience URI while in shelter were adopted at higher rates, thus experienced shorter LOS. Since the presence of a hiding den was significantly associated with lower URI incidence, their inclusion in kennel enclosures may have positive welfare, LOS, and adoption implications for shelter cats.