“Anti-Fel D 1 Immunoglobulin Y Antibody-Containing Egg Ingredient Lowers Allergen Levels in Cat Saliva”, 2019 (; backlinks):
Objectives: Fel d 1 is the major cat allergen, causing IgE reactions in up to 90% of cat-allergic adults. Fel d 1 secreted in saliva is spread to the haircut during grooming. Current management includes attempts to reduce or eliminate exposure to Fel d 1. A novel approach to reducing immunologically active Fel d 1 (aFel d 1) exposure, which involves binding the Fel d 1 with an anti-Fel d 1-specific polyclonal egg IgY antibody (sIgY), was evaluated. The hypothesis was that saliva from cats fed diets containing this sIgY would show a significant reduction in aFel d 1.
Method: Two trials in cats were completed. In trial 1, saliva was collected 0, 1, 3 and 5h post-feeding during a 2 week baseline and subsequent 6 week treatment period. Trial 2 included a control and treatment group, and saliva was collected once daily. Trial 2 cats were fed the control diet during a 1 week baseline period, and then fed either control or sIgY diet during the 4 week treatment period. Fel d 1-specific ELISA was used to measure salivary aFel d 1. Data were analysed using repeated-measures ANOVA and a linear mixed-model analysis.
Results: Salivary aFel d 1 decreased post-treatment in both trials. There were no differences in aFel d 1 based on time of collection relative to feeding in trial 1. In trial 2, 82% of treatment group cats showed a decrease in aFel d 1 of at least 20% from baseline vs just 38% of control cats. Only one (9%) treatment cat showed an increase in aFel d 1 vs 63% of control cats.
Conclusion: Feeding sIgY substantially reduced aFel d 1 in the saliva of cats within 3 weeks. Although additional research is needed, these findings show promise for an alternative approach to the management of allergies to cats.