Anna Maria De Marinis

Hair identification key of wild and domestic ungulates from southern Europe

Abstract We analysed macro- and microscopic features of dorsal guard hairs in 105 specimens of 10 wild and five domestic ungulates from southern Europe to work out a dichotomous key with a photographic reference system of diagnostic hair features. We integrated and extended the available data on hair morphology of wild ungulates and provide a first comparative analysis of hair structure of domestic forms. To develop the key, we used clearly recognisable qualitative characters of cuticle and medulla. The techniques used in this study can be easily, quickly and economically applied in routine investigations, keeping the time required to identify a sample at a minimum. The accuracy of the key was assessed through a blind test carried out by four trained observers. We describe the effects of age and season on the microscopic structure of hair, which have not yet been described in European literature. A review of all the available data on hair morphology of wild ungulates is presented and the relevant differences between domestic forms and their relative wild ancestors that have arisen during the domestication process are described. A hair identification key has a wide range of practical applications in biology, such as the study of carnivore feeding habits through scat analysis.

Ecological factors affecting eruption timing of mandibular teeth in roe deer

Increasing evidence suggests that conditions in early life have important consequences for body size and fitness in mammals. As regards herbivores, teeth play a central role in the long-term performance of individuals. So far, however, patterns of teeth eruption have been scarcely investigated in relation to environmental and climatic factors experienced by herbivores. We described the eruption timing of mandibular teeth in a population of roe deer (Capreolus capreolus) located in the Apennines (Central Italy), through the analysis of 2161 jaws of fawns (1176 females and 985 males) shot in their first winter of life over three hunting seasons (2013–2015). Results showed that the percentage of juveniles exhibiting permanent teeth depends on the cohort. Among the factors that may affect both incisiviform and molariform teeth replacement timing, our findings include body mass and population density. Additional factors determining the relative speed of teeth replacement are (1) food availability for the mother during the last part of gestation, the birth period and the lactation, (2) winter temperature experienced by the mother, and (3) temperature experienced by fawns during their first summer and autumn. Besides, for the first time in literature, elevation was reported to delay front teeth replacement. A greater number of climatic factors were found to shape the eruption timing of the third molar (M3) in comparison to that of incisiviform teeth. Also, a different pattern was found in males and females. The eruption of M3 is, indeed, a costly and long-lasting process requesting optimal nutritional conditions and the meeting of a threshold jaw size. Our results indicate a strong correlation between environmental conditions and eruption process, i.e., between resource availability during the gestation and rearing periods and eruption timing.