Transepidermal water loss in cats: comparison of three differently clipped sites to assess the influence of hair coat on transepidermal water loss values.

Abstract

BACKGROUND: The measurement of transepidermal water loss (TEWL) is one of the parameters that can be used to assess skin barrier function. The variability and reliability of TEWL measurements in dogs have been controversial, and the hair coat has been considered as one of the factors that may cause variation of TEWL values. HYPOTHESIS/OBJECTIVES: The aims of the study were to establish a suitable procedure for measuring feline TEWL, to evaluate the influence of hair coat on TEWL measurements and to assess variations of TEWL at different anatomical sites. METHODS: Transepidermal water loss was measured using a closed-chamber evaporimeter, the VapoMeter(®). We compared three adjacent sites in the groin area of 10 clinically normal, domestic short hair cats. One site was unclipped, the second was trimmed with scissors and the third was shaved using electric clippers. Values of TEWL were obtained for 48 h after trimming with scissors and clippers. Five sites were clipped (upper back, lumbar back, lateral thigh, axillae and groin), and the TEWL was measured. RESULTS: The mean and SD of TEWL values of the clipper-trimmed site were the smallest, followed in order by the site trimmed with scissors and the unclipped site. The TEWL values were statistically constant in the clipper-trimmed site, while the values in the unclipped sites were not. There was no statistically significant difference in TEWL values between all of the anatomical sites except for the axillae. CONCLUSIONS AND CLINICAL IMPORTANCE: Hair clipping of sites with electric clippers is recommended for TEWL measurement in cats.