MAPPING THE CANINE SKIN - A STUDY OF COAT RELATIVE-HUMIDITY IN NEWFOUNDLAND DOGS

An instrument is described which uses air aspirated via a narrow probe from an animal's hair coat to assess the relative humidity (RH) of ai r within the coat. This was used to investigate regional differences i n coat humidity in a group of 21 Newfoundland dogs maintained in a con stant environment of 40% RH. At sites over the rump, mid-lateral thigh and chest wall, the coat RH was about 50%, whilst beneath the tail an d on the ventral neck the RH was about 70%. It was observed that at ta il and neck sites the RH rose with increasing age of the subject. No d ifferences were observed related to the coat colour or sex of the subj ects, but coat type was relevant. The relative humidity of finer coats on exposed sites was about 7% lower than those of normal coats. The p hysical features affecting these findings, i.e. convection, conduction and the effect of matting, are discussed, together with the implicati ons for microbial colonization.