The Scanning Electron and Light Microscopic Structure of Bovine Tactile Hair

Performance scanning electron microscopic investigations and elemental analysis of hair of the different animal species for forensic identification

Veterinary forensics have attracted less attention compared with human forensics. Animal hair morphological examination using scanning electron microscopy (SEM) and hair mineral analysis using energy-dispersive X-ray fluorescence (ED-XRF) provide reference databases for animal hair identification used in forensic investigations. This study was performed on four different animal species: large ruminants (buffalo and cattle), small ruminants (goat and sheep), carnivores (cat and dog), and equines (donkey and horse). The hair scale pattern, scale margin type, and distance between scales were identified. The hair scale pattern was imbricate in large ruminants, goat, and horse; coronal (crown-like) in carnivores and donkey; and spinous in sheep. The morphometric measurements, including cuticle layer thickness, cuticle scale height, cortex diameter, and hair shaft width were recorded. The highest cuticle thickness was found in horse, and the highest cuticle hair scale was detected in cattle. Moreover, the largest cortex diameter was measured in buffalo, whereas the smallest one was in cat. With regard the content of hair elements, some elements were specific for the hair of certain tested animals, such as bromine in sheep and magnesium and phosphorus in buffalo. In addition, vanadium and titanium were found only in cattle and dog, and the latter element was also detected in sheep. In conclusion, this study provides two techniques for animal hair identification that can be used in forensic investigations.

Histomorphological investigations on the lips of Rahmani sheep (Ovis aries): A scanning electron and light microscopic study

This study was conducted to provide comprehensive information on the anatomical and histological features of the upper (UL) and lower (LL) lips of Rahmani sheep by gross examination, morphometric analysis in addition to Light and scanning electron microscope (SEM). Samples from normal healthy adult male sheep heads were collected directly after slaughtering. UL and LL were dissected, and specimens were collected for both light and SEM. The UL was longer approximately by one-fold and thicker by one-fold at the median and the oral angle areas, and by one- and half-folds at the paramedian area than the LL. The free border of both lips was characterized rostrally by the presence of labial projections. By SEM the edges of the inner aspect of the lips and of the philtrum were distinguished by labial projections. These projections which surrounding the philtrum subdivided into polygonal areas with numerous keratinized scales especially at the apical parts which increased dorsally toward the nostril. Most of the openings of the upper labial salivary glands were volcanic crater-shaped while that of the lower labial salivary glands were various shapes; round folded margin, rosette and whirlpool shaped. Histologically, the shape of the projection or papillae differs at the median and paramedian areas of the UL than the LL. However, there was no differences near the oral angle area. In conclusion, the shape, size and amount of keratinization of the papillae may offer efficiency to the lips during feeding process.

Histological Organization of Collared Peccary (Tayassu tajacu) Lip

Collared peccary (Tayassu tajacu) belongs to the Tayassuidae family that is characterized by a dorsal scent gland located in the middle of the hump. It can be found from south-west United States to Argentina. It is a very well-adapted animal that can survive different environments, having a varied diet. Very little morphological information of the animal is available, except that concerning the reproductive tract. This study describes the histological organization of the collared peccary lip. The lip marks the junction between the integument and digestive system. It is lined by skin on the outer surface and mucosa on the inner surface. Skin appendages such as hair follicles and glands are usually found on the outer surface. The collared peccary's lip shows, on the outer surface, simple and sinus hair follicles as well as sebaceous and apocrine sweat glands. No salivary gland is found on the inner surface, and deep in the connective tissue pacinian corpuscles can be found. The connective tissue is rich in collagen and elastic fibres. The collared peccary's lip may be used not only for food prehension but also functions as a sensitive structure giving tactile input to the central nervous system.