Scanning electron microscopy of the nasal skin in different animal species as a method for forensic identification.

The current study aims to provide a new method for the identification of animal species by using the scanning electron microscopic study on the nasal skin around the nostril. The reference databases for animal identification using traditional ways (i.e., hair and bone analyses) were somewhat available. This study was conducted on the nasal skin of seven different animal species: large ruminants (Saidi buffalo and frozen Angus cattle); small ruminants (Egyptian goat and Rahmani sheep); camels (one-hump dromedary camel); equines (African domestic donkey and Arabian horse); carnivores (farm domestic cat, Egyptian Baladi dog, and red fox); swine (Danish Landrace pig); and rodents (albino rat and New Zealand white rabbit). The nasal skin was divided by grooves into different shaped raised areas in some examined animals, the mean diameter of these areas and width of the grooves of each animal species were recorded. The characteristic differential features of the nasal skin of each animal species have been documented. Few openings of the nasolabial glands were demonstrated in large ruminants and swine, which were H letter-shaped in buffaloes, oval-shaped in cattle, and whirlpool-shaped with several layers of folds on their margin in pig. Moreover, the openings of the lateral nasal glands were whirlpool, ovoid, and oval shaped in goats, sheep, and camels, respectively. In conclusion, the present study proved that the skin around the nostrils plays an important role as means of identification in forensic investigations and improves the field of veterinary forensic medicine in general, which is not well-developed in comparison with human forensics.