The relationship between hair structure, age and sex of animals

Ascertaining the age and sex of a particular animal as well as its breed me rely on the basis of a fragment of its body is no easy task. It is, nonethe less, of great significance during police or prosecutor's investigations in to cases of poaching or stealing. Laboratory experts sometimes have only fr agments of the animal's skin, which, in addition have often been technologi cally or thermally altered. Ascertaining the animals species through serolo gical tests is therefore difficult and using hair structure in order to do so prove to be a useful alternative method in such cases. Hairs may be foun d in all types of animal material. The hairs of animal species are signific antly different in terms of their structure. Yet there is a lack of informa tion concerning hair structure within particular species as such. The aim of this study was to determine the interrelationship between the mi croscopic structure of hair, body weight and the sex of animal and the loca tion of the hair. The investigations were carried out on swine which were d ivided into groups according to body weight and sex. Hairs were taken from the back and abdomen Microscopic scanning tests did not reveal any differen ces in the shape of the hair scale, its location and number on an area of 1 mum in relation to the age and sex of the animal. The characteristic which varied was hair thickness, which increased significantly together with an increase in body weight. Male hairs were thinner than those of females. No differences were noted, however, between hairs taken from different places on the back or abdomen of the swine. Regression analysis indicated that hai r thickness is directly related to body weight (R-2 < 0.90; p <less than or equal to> 0.001) rather than sex differences (R-2 < 0.60; p <less than or equal to> 0.01) amongst swine and thus may be a helpful criterion in determ ining an animal's age. This relation, however only refers to this particula r swine population and may be different in the case of other breeds of swin e or other animal species.