Mandibular shape in farmed Arctic foxes (Vulpes lagopus) exposed to persistent organic pollutants

Abstract

We investigated if dietary exposure to persistent organic pollutants (POPs) affect mandibular asymmetry and periodontal disease in paired male-siblings of Arctic foxes (Vulpes lagopus). During ontogeny, one group of siblings was exposed to the complexed POP mixture in naturally contaminated minke whale (Balaenoptere acutorostarta) blubber (n = 10), while another group was given wet feed based on pig (Sus scrofa) fat as a control (n = 11). The ∑POP concentrations were 802 ng/g ww in the whale-based feed compared to 24 ng/g ww in the control diet. We conducted a two-dimensional geometric morphometric (GM) analysis of mandibular shape and asymmetry in the foxes and compared the two groups. The analyses showed that directional asymmetry was higher than fluctuating asymmetry in both groups and that mandibular shape differed significantly between the exposed and control group based on discriminant function analysis (T = 58.52, p = 0.04, 1000 permutations). We also found a non-significantly higher incidence of periodontal disease (two-way ANOVA: p = 0.43) and greater severity of sub-canine alveolar bone deterioration similar to periodontitis (two-way ANOVA: p = 0.3) in the POP-exposed group. Based on these results, it is possible that dietary exposure to a complexed POP mixture lead to changes in jaw morphology in Arctic foxes. This study suggests that extrinsic factors, such as dietary exposure to POPs, may affect mandibular shape and health in a way that could be harmful to wild Arctic populations. Therefore, further studies using GM analysis as an alternative to traditional morphometric methods should be conducted for wild Arctic fox populations exposed to environmental contaminants.

A risk assessment review of mercury exposure in Arctic marine and terrestrial mammals

“…The closest recent example was POP effect studies using minke whale (Balaenoptera acutorostrata) blubber to expose sledge dogs (Canis familiaris) and Arctic fox (Alopex lagopus) as sentinels for the polar bear, which are better that seal data, but unfortunately this was never carried out with a focus on Hg (e.g. Bradley et al, 2018;Kirkegaard et al, 2010aKirkegaard et al, , 2010bKirkegaard et al, , 2011Pedersen et al, 2015;Rogstad et al, 2017;Sonne, 2010;Sonne et al, 2005Sonne et al, , 2006aSonne et al, , 2006bSonne et al, , 2006cSonne et al, , 2007aSonne et al, , 2007bSonne et al, , 2007cSonne et al, , 2008aSonne et al, , 2008bSonne et al, , 2008cSonne et al, , 2008dSonne et al, , 2008e, 2009aSonne et al, , 2009bSonne et al, , 2010bSonne et al, , 2014aSonne et al, , 2014bSonne et al, , 2017Verreault et al, 2008). Other examples effect evaluation is the use of Risk Quotients comparing body burden and critical body residues estimated from PBPK modelling from rats and mice relative to immunologic, reproductive and carcinogenic effects, but such studies does not provide a better and more relevant picture relative to population effect of Arctic species in focus of this assessment (Sonne et al, 2009c(Sonne et al, , 2015(Sonne et al, , 2016Dietz et al, 2015Dietz et al, , 2018a.…”

Persistent, Bioaccumulative, and Toxic Chemicals in Wild Alpine Insects: A Methodological Case Study

“…Another prominent effect of POPs is genotoxicity causing, for example, DNA strand breaks (Martínez‐Paz et al, 2013). Phenotypic changes such as alterations in size, shape, or fluctuating asymmetry have also been found to be consequences of high POP loads in vertebrates (Bradley et al, 2019; Jenssen et al, 2010; Romero et al, 2017).…”