Effect of a Pheromone on Stress-Associated Reactivation of Feline Herpesvirus-1 in Experimentally Inoculated Kittens.

Background: Stress contributes to reactivation of feline herpesvirus-1 (FHV-1). The usage of pheromones to decrease stress in FHV-1 experimentally inoculated kittens has not previously been investigated. Hypothesis/Objectives: To determine whether a feline pheromone would lessen stress, resulting in decreased recurrence of FHV-1-associated illness in kittens. Animals: Twelve 5-month-old, purpose-bred kittens. Methods: Randomized, double-blind, placebo-controlled clinical trial. Kittens previously infected with the same dose of FHV-1 were randomized into 2 separate but identical group rooms. After a 2-week equilibration period, a diffuser containing either the pheromone or placebo was placed in each of the rooms, and the kittens acclimated for an additional 2 weeks. Every 2 weeks thereafter, for the 8-week study period, housing was alternated between kennel-and group housing. Blinded observers applied a standardized clinical and behavioral scoring rubric daily. After each 2-week period, serum cortisol concentrations and quantitative PCR for FHV-1 and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) ratios were evaluated. Clinical, behavioral, and laboratory test results were compared between groups within individual and combined study periods. Results: Sneezing occurred more frequently in the placebo group during individual (P = 0.006) and combined study periods (P = 0.001). Sleep at the end of observation periods occurred more frequently in the pheromone group during individual (P = 0.006) and combined study periods (P < 0.001). Conclusions and Clinical Importance: The findings suggest that the pheromone decreased stress, and the decrease in stress response may have resulted in decreased sneezing associated with FHV-1.