P‐2 Evaluation of the influence of sex, diet and time on skin pH and surface lipids of cats

Abstract

Skin lipids and pH are two factors classically considered of importance in homeostatic characteristics of skin. Skin physiology in cats has received little attention. The aim of this study was to evaluate the long‐term influence of sex, sexual status, season, and dietary fat and energy on these parameters. Twenty‐four European short‐haired laboratory cats, 14 months of age, were followed over a 1‐year period. They were divided into 8 groups of three, according to: sex (12 males and 12 females), sexual status (intact or neutered) and diets [(high energy 4300 kcal/kg as fed, 21% fat) vs. (moderate energy 3500 kcal/kg as fed, 10% fat)]. Both diets were fed to all cats for 6 months following a cross‐over design. Parameters regularly evaluated were skin pH and hair total lipid content (extraction from samples of 0.6–1.2 g of clipped hairs). The pH of the skin varied from 6.6–6.8 initially to 7.2–7.4 at the end of the study. This increase was significant only in intact animals (male and female). The dietary changes did not affect skin pH. Hair total lipid content was not affected by sex or the diets but slightly increased in all groups over the study period from 1.5–2.4 to 2.4–3.3%. In conclusion, skin pH appeared to be potentially modified by sexual status, but not by sex or dietary lipids and energy. Hair lipids do not appear to be affected by sex or increases in dietary lipids and energy. The slight increase in pH and hair lipids during the study was attributed to the change from young adult to adult stage of all cats. Funding: Royal Canin.