Age-Related Patterns in Trace Element Content Vary Between Bone and Teeth of the European Roe Deer (Capreolus capreolus)

Abstract

Game animals, such as the roe deer (Capreolus capreolus), have long been used as bioindicators of environmental contamination. Most ecotoxicological research on ungulates has focused on trace element content in soft tissues and antlers. Also, only fragmentary information exists about whether and how trace element concentrations vary with the age of wild-living animals and whether these age-related patterns are similar for different types of tissues. The purpose of this study was to measure concentrations of seven trace metals (barium, copper, iron, lead, manganese, strontium, zinc) and fluoride in bone and teeth of roe deer and to determine whether significant variation is evident with individual age. For this purpose, we collected permanent molars and fragments of mandible bone from more than 130 female roe deer in Central Poland. We found that concentrations of four trace elements (barium, manganese, zinc, and fluoride) in teeth of deer showed positive linear relationships with individual age. No such trends were recorded for trace element content in bone. We suggest that these striking differences in age-related patterns of trace element bioaccumulation between bone and permanent teeth of roe deer might be explained by higher turnover rate and constant remodelling of bone tissue. The results suggest that analysis of permanent teeth may be useful for assessing throughout-life intoxication by environmental pollution in the roe deer and possibly in other mammal species. Our study reinforces the need to carefully account for age-related variation in ecotoxicological research on wild-living animals.Electronic supplementary materialThe online version of this article (doi:10.1007/s00244-017-0470-1) contains supplementary material, which is available to authorized users.

Ecotype Variation in Trace Element Content of Hard Tissues in the European Roe Deer (Capreolus capreolus)

“…However, cervids usually produce new antlers each year, and thus, they are not particularly suitable to investigate long-term exposure to pollutants. Taking all this into account, bone and teeth are expected to more reliably indicate long-term bioaccumulation of pollutants, and consistent with this prediction, we have recently shown that heavy metal content of permanent teeth reliably indicate throughout-life intoxication by environmental pollution in the European roe deer (Demesko et al 2018). …”

“…A total sample of 233 skulls was collected (139 and 94 samples for the forest and field ecotype, respectively). Age of sampled specimens varied between 2 and 12 years, as assessed based on dental wear by the members of the Regional Commissions for Hunting Evaluation (details in Demesko et al 2018). For the purpose of analyses, four age classes were recognized: (i) 2 years old ( n  = 77), (ii) 3–4 years old ( n  = 70), (iii) 5–6 years old ( n  = 49), and (iv) > 6 years old ( n  = 27).…”

“…To test whether ecotype-related differences in trace element content were similar for both sample types, we also entered an ecotype-sample type interaction in each model. As age-related bioaccumulation rate of trace elements can vary between bone and teeth of the roe deer (our previous research on roe deer provided support for positive correlations between trace element concentrations and age in teeth, but not in bone (Demesko et al 2018)), we also included age-sample interaction to account for these differences. Because teeth and bone samples were collected from the same individuals, we included individual identity as a random factor to avoid pseudoreplication (Hurlbert 1984).…”

Comparison of Element Concentrations (Ba, Mn, Pb, Sr, Zn) in the Bones and Teeth of Wild Ruminants from the West Carpathians and the Tian-Shan Mountains as Indicators of Air Pollution

“…However, the concentrations of Ba, Mn and Zn in teeth of roe deer showed positive linear relationships with individual age. No such trends were recorded for trace element content in bones [71].…”

“…We used two different tissues: Bones and teeth. The analysis of ruminant permanent teeth is a useful indicator for assessing life-long intoxication by environmental pollution [71]. However, the concentrations of Ba, Mn and Zn in teeth of roe deer showed positive linear relationships with individual age.…”