Human Interaction And Shelter Cat Health
Research has shown that feeling happy stimulates mucosal immune response, and that happier humans have lower rates of upper respiratory disease (URD) than humans who are less happy. Like humans, the mucosal immune response of cats is also linked to their emotional state. Since higher levels of the mucosal immune antibody S-IgA protects against pathogens commonly found in shelters, the researchers in this study hypothesized that creating a sustained positive environment for shelter cats through positive human interaction could boost cats’ levels of S-IgA and reduce the prevalence of URD.
The cats used for this study were taken in by the Vancouver Branch of the British Society for the Prevention of Cruelty to Animals. Upon admission to the shelter, healthy cats were transported to the study ward and recorded for one hour. An experimenter then methodically approached each cat similar to how a volunteer shelter worker would do, eventually opening the cat’s cage door and extending their hand towards the cat. Cats were rated as Anxious, Frustrated, or Content* based on their behaviors during the recording and interaction period.
96 content cats were divided into a treatment (n = 47) and control (n = 49) group. Cats in the treatment group received human interaction for 10 minutes a day, four times per day, for a total of 10 days. Cats in the control group had experimenters stand in front of their cages with their eyes averted for the same amount of time each day. Each period of human interaction in the treatment group was rated as positive or negative. In addition, their behaviors were recorded for 10 minutes every hour and rated as anxious, frustrated, or content. Their stool was collected and tested for S-IgA and their amount of viral shedding (a sign of infection) was documented.
Cats in the treatment group who received daily interaction remained content 90% of the time, compared with 84% of the time for cats in the control group who received no interaction. Cats in the control group were also more likely to display negative emotions than those in the treatment group. Though the cats showed no initial difference in the amount they shed, cats in the control group shed more over time.
Cats in the treatment group who developed URD were less likely to respond positively to human interaction (83%) than cats who did not develop URD (96%). In total, 9 out of 47 cats in the treatment group developed URD compared to 17 out of 49 cats in the control group, a difference of 15.6%. Treated cats had significantly higher amounts of stool than control cats, and also had higher levels of S-IgA. Of the treated cats, those who displayed content behaviors had higher S-IgA levels than those who became anxious or frustrated. Content cats in the treatment group also had higher S-IgA levels than content cats in the control group.
The researchers concluded that daily interaction with humans helps cats sustain positive mood, which in turn boosts their level of S-IgA and increases their immunity to developing URD. Cats who did not receive such interaction were more likely to exhibit signs of infection (shedding) and develop URD, suggesting that a positive human interaction can play an important role in respiratory health.
*Anxious and frustrated cats were entered into separate studies respectively examining the effects of gentling and cognitive enrichment. The results of those studies were reported elsewhere, with the study on frustrated cats still pending publication at the time this study was published.