Schlüsselwort: Skin Diseases

The dietary influence of evening primrose oil in cats with chronic skin diseases The aim of this study was to evaluate whether supplementation with evening primrose oil, and the γ-linolenic acid (GLA) it contains, influences inflammatory processes in cats with chronic skin diseases and leads to an improvement in their clinical symptoms. To this end, the effects of evening primrose oil and sunflower oil were compared in a randomised, placebocontrolled, double-blind study of 29 cats with feline atopic dermatitis. Blood samples and clinical examinations to evaluate the dermatological condition were performed before and after the eight-week feeding trial. The blood samples were used to determine the fatty acid concentrations in the plasma and to carry out immunological, haematological and blood chemistry investigations. Skin lesions were assessed using SCORFAD, a validated method for the evaluation of the most frequently identified skin reaction patterns in allergic cats. Evening primrose oil led to a significant increase in plasma concentrations of GLA and its conversion product DGLA (dihomo-γ-linolenic acid) (p < 0.05). The administration of evening primrose oil resulted in a reduction of the inflammation modulating cytokines interleukin 6 and interleukin 8, which could be statistically confirmed for interleukin 6 in cats with excoriations (p < 0.05). With sunflower oil, none of these effects were recorded. There was no correlation between the laboratory-analysed results and the clinical results. Clinical improvement was observed in both feeding groups equally. Some 50 to 57 per cent of the cats given evening primrose oil and 50 to 82 per cent of the cats given sunflower oil showed fewer skin lesions in the reaction patterns of miliary dermatitis, self-induced alopecia and excoriations. Statistically, no difference between the groups could be documented. The unequal severity of the lesions for assessment was noteworthy and possibly limiting for the outcome of the study. In this study, evening primrose oil demonstrated an anti-inflammatory effect in cats on an immunological level, but did not achieve better clinical effects when compared to sunflower oil. The biochemical parameters show that oral administration of evening primrose oil may be recommended as a complementary treatment option for cats with chronic skin diseases.