Hair histology as a tool for forensic identification of some domestic animal species

Abstract

Animal hair examination at a criminal scene may provide valuable information in forensic investigations. However, local reference databases for animal hair identification are rare. In the present study, we provide differential histological analysis of hair of some domestic animals in Upper Egypt. For this purpose, guard hair of large ruminants (buffalo, camel and cow), small ruminants (sheep and goat), equine (horse and donkey) and canine (dog and cat) were collected and comparative analysis was performed by light microscopy. Based on the hair cuticle scale pattern, type and diameter of the medulla, and the pigmentation, characteristic differential features of each animal species were identified. The cuticle scale pattern was imbricate in all tested animals except in donkey, in which coronal scales were identified. The cuticle scale margin type, shape and the distance in between were characteristic for each animal species. The hair medulla was continuous in most of the tested animal species with the exception of sheep, in which fragmental medulla was detected. The diameter of the hair medulla and the margins differ according to the animal species. Hair shaft pigmentation were not detected in all tested animals with the exception of camel and buffalo, in which granules and streak-like pigmentation were detected. In conclusion, the present study provides a first-step towards preparation of a complete local reference database for animal hair identification that can be used in forensic investigations.

Mummified animal skin with tar content from the castle of the late medieval town of Novo Brdo (Central Balkans)

“…5a). These features correspond to goat cuticles, as previously described in literature (De Marinis and Asprea, 2006;Ahmed et al, 2018;Þórhallsdóttira et al, 2019). However, there are similarities between goat and cattle cuticular scale patterns; in the case of cattle, the pattern is continuous but not so prominent, with relatively smooth margins, while the goat cuticle is prominent with rippled margins.…”

“…5g). While similar features of sheep cuticular scale patterns have been reported previously (De Marinis and Asprea, 2006;Ahmed et al, 2018;Þórhallsdóttira et al, 2019), the average of the mid-shaft diameter in all four cases (81.2 ± 0.77 μm, 81 ± 0.88 μm, 79.1 ± 0.61 μm, and 79.1 ± 0.74 μm) corresponds to the reference collection metric data for a sheep (Supplementary material). The results clearly indicate that hair samples in all four cases of the mummified animal skin are composed of sheep fleece (wool).…”

Multidimensional Profiling of Human Body Hairs Using Qualitative and Semi-Quantitative Approaches with SR-XRF, ATR-FTIR, DSC, and SEM-EDX

“…SEM is presented as a very attractive technique for non-destructive and high-resolution imaging of the hair cuticle scale ultrastructure for morphometric analysis using computer software. Although morphometric analysis is often used in wildlife forensic studies for species differentiation and identification by assessing hair cuticle scale morphological characteristics such as cuticle scale patterns, the margin type, as well as shape and distance between scales [ 49 , 50 , 51 ], morphometric profiling of different body hair cuticle scales has never been investigated. We are only aware of one study that focused on studying the morphology of different body hairs in a male participant [ 52 ] and one that assessed cuticle scale morphometrics and showed differences based on gender and sampling region on the head, similar to our study [ 53 ].…”

Scanning electron microscopy and morphometric analysis of the hair in dromedaries with SEM-EDX in relation to age

“…Previous research has shown that the medulla of Maghrebi camel hair fibers was 50% continuous, 38% fragmented, and 12% interrupted [ 45 ]. The adult male one-humped camel’s cortex was pigmented, and the medulla had a continuous, smooth margin [ 13 ] and camel hair is divided into two parts: thin, non-medullated, or medullated hair fibers and thick, interrupted, or continuous medulla hair fibers [ 24 ]. Comparatively, the dog’s medulla is an exception and is comprised multicellular cornified cells [ 46 ], the medullary structure extended into the root and contained traces of follicular tissue.…”

“…In criminal investigations, hair inspection is used as typical physical evidence; it is essential to ascertain if the hair is of human or animal origin and to identify the animal species [ 13 , 14 ]. Hair is stable under adverse natural conditions, making it useful in forensic investigations and resistant to postmortem changes such as chemical and environmental degradation [ 15 ].…”