Multiple cranial pathologies in spotted hyaenas, Crocuta crocuta

Abstract

Spotted hyaenas are generally considered to have resilience against injuries and pathogens, and the incidence of pathologies is scarcely reported. However, it is important for ecological studies and conservation efforts to have a clear overview of the physical threats that can occur in the life of a species. The present paper describes and interprets several osteopathologies in the crania of the spotted hyaena, Crocuta crocuta, in the collections of the Royal Museum for Central Africa (RMCA) in Tervuren, Belgium. Of the fifty-two specimens from central Africa examined, twenty-three (i.e., 44 %) of them showed evidence of pathologies, including injuries, congenital pathologies, and disease. Selected specimens were scanned using Computed Tomography and their internal cranial structures were studied. Here we describe and discuss the different types of pathologies evident in the crania of these hyaenas: craniosynostosis, microtia, osteomyelitis and periodontitis, as well as a trauma indicated by cranial fractures, dental fractures, and bite puncture marks. Some pathologies reported herein are novel for hyaenas, and there are some instances of multiple pathologies in the same individual. Implications of these pathologies, including the social interactions of hyenas, conservational threats, as well as biased data sampling, are highlighted. This study improves our knowledge of disease and trauma experienced by hyaenids, and provides a better understanding of their biology, and the potential threats faced by these iconic animals. This case study offers a comparative base for similar studies in other carnivorans, to clarify the pathological background of apex predators.

Keywords: Brachycephaly; Carnivora; Competition; Ecology; Hyaenidae.