Elemental characterization of antlers of various deer species using X-Ray Fluorescence (XRF): A tool for forensic examination

Forensic Sci Int. 2022 Mar:332:111172. doi: 10.1016/j.forsciint.2022.111172. Epub 2022 Jan 12.

Abstract

Antlers are unique characteristic of males of family Cervidae. It fully regenerates each year in relation to their sexual cycles. It is primarily used as weapons in intra-specific fighting or possibly as organs displaying strength. These are formed by the calcification, beneath the velvet of the fast growing pre-osseous tissue known as velvet antlers. Continuous dividing velvet antlers replace dead antlers every year through shedding. Antlers are composed primarily of minerals, protein, carbohydrates and fatty acids. Calcium and phosphorus, primarily present as hydroxyapatite [Ca5(PO4)3OH] (Chapman 1975). In India there are nine species of deer viz. Kashmir stag (Cervus elaphus), mouse deer (Tragulus meminna), musk deer (Moschus moschiferus), swamp deer (Rucervus duvaucelii), thamin (Rucervus eldii), barking deer (Muntiacus muntjak), chital (Axis axis), hog deer (Axis porcinus) and sambar (Rusa unicolor). Mouse deer and musk deer possess only canines and antler is absent in both the deer species. Previously, the export of shed antlers and peacock feathers was allowed in India. Although, antlers are not very extensive in illegal wildlife trade but artifacts of antlers and they are used for traditional medicines for treatment of various diseases in different countries. The problem of illegal trade of antlers is mainly due to the mis-declaration of its quantity. Mostly antlers of chital, sambar and swamp deer are widely traded. Visualizing the current status of some of the deer species, trade of antler in India has been recently banned. Therefore, to provide legal protection to deer and other related species accordingly brow-antlered deer (Rucervus elidii), hog deer (Axis procinus), and swamp deer (R. duvaucelii) are included in Schedule I, whereas barking deer (Muntiacus muntjak), chital (Axis axis), and sambar (R. unicolor) were in schedule III of Wildlife (Protection) Act, 1972. To strengthen the legal measures and to protect deer species, identification of antlers in complete, pieces or pulverized form is very important. Very few scientific studies deal with identification of antlers belonging to different species. Thus, present study is aimed to identify species from antlers using species specific signature using elemental analysis. Morphological features of antlers in artiodactyls often used as a diagnostic tool to identify species. Although, morphometry is very good technique to identify antlers but as malformation in antlers is common also antlers are seized either in complete form or in small pieces or powder form, therefore, identification through morphometry becomes difficult for deformed antlers or pieces. In such cases, elemental analysis is helpful. Elemental composition of antlers of different species helps in inter-species distinction. This study will help managers, scientists and enforcement agencies to identify species from parts and products of antler.

Keywords: Antler; Conservation of deer species; Elemental profile; X-Ray Fluorescence (XRF).