Trace elements in moose (Alces alces) found dead in Northwestern Minnesota, USA

Essential differences in the mineral status of free-ranging European bison Bison bonasus populations in Poland: The effect of the anthroposphere and lithosphere

Tracking the concentration of elements in the organs of endangered animal species can provide significant knowledge about environmental hazards and allows more targeted protective measures to be taken. In this paper the differences in concentrations of 27 elements in the livers of free-ranging European bison were studied. The ICP-OES method was applied to study the four main Polish populations, which live in lowland (Białowieska, Knyszyńska and Borecka forests) and mountain (Bieszczady) habitats. The study was based on a unique and relatively large amount of comparative material. It was found that European bison populations that live in different locations differ from each other in terms of the hepatic concentrations of 17 of the elements studied in this work. The mountain population in Bieszczady was most distinctive due to the higher concentrations of Ba, Ca, Cd, Se, and the lower concentrations of Mo and V (compared to the other populations). Additionally, even geographically close lowland populations sometimes have different hepatic concentrations of particular elements. The sex and age of individuals have a weak effect on mineral status. Although the lithosphere is the primary factor that affects the availability of elements for the European bison, the soil parameters and biosphere can significantly affect the availability of elements, e.g. by accumulation. It was also shown that the anthroposphere plays a role, but this is mainly through agriculture as feeding on arable fields significantly changes the mineral status of European bison. The need for further research, especially on Cd, Se and Cu, was indicated. It was concluded that toxic elements or deficiencies in essential elements in the populations of the studied species should be considered locally as this would allow better understanding of the health condition of individual populations.

Geochemical landscapes as drivers of trace and toxic element profiles in wild red deer (Cervus elaphus)

Tissue concentrations of essential trace and toxic elements in red deer (Cervus elaphus) are associated with the plants, soil and water they ingest. As such, variation in tissue concentrations is associated with variation in local geochemistry and bioavailability of elements. Physiological factors such as liver fluke (Fasciola hepatica) infection, breeding status, and in-tissue element interactions may also affect tissue concentrations, though their effects in red deer are not well understood. The primary objective of this study was therefore to survey wild red deer liver element concentrations across a range of geographically distinct populations during the Scottish red deer stalking season; and, in so doing, establishes element reference ranges while also exploring geographic and temporal variation and physiological factors. Livers were sampled from carcasses intended for human consumption on nine hunting estates during two seasons (2012-13, 2013-14). Samples were digested and analysed by ICP-OES for essential trace elements (Co, Cu, Fe, Mn, Mo, Se, Zn) and for Cd. Data (n=787) were modelled against cull location, date, and F. hepatica diagnosis. Interactions between elements within liver, and differences in element profiles between estates, were explored by principal component analysis. Our results revealed marked geographic variation in Cd, Cu and Se, where up to four-fold differences in median element concentrations occurred between estates, and, in males, Mn, Mo and Zn declined as the breeding season approached. In both sexes, within-liver associations (Cd-Cu-Se and Mn-Mo-Zn) were found. In females, liver Zn was greater on average in individuals that were not infected with F. hepatica. This study is the first to quantify geographic variation in Scottish red deer liver element concentrations; the drivers of which remain to be explored (and may be management related), and, the consequence of which may affect sub-clinical health.

Relationship between Cd and Zn concentration in the kidneys, liver, and muscles of moose (Alces alces) from north-eastern Poland

The aim of the study was to evaluate the cadmium and zinc content in the kidneys and liver of moose from north-eastern Poland. Animals were divided with respect to their age. The mean concentration of cadmium in the kidneys of moose studied was 11.31 mg kg^-1, while in the liver it amounted to 2.68 mg kg^-1. Age had a significant effect on the content of cadmium in both organs. In the muscles of most animals studied, the cadmium concentrations were below the detection limit. Elevated concentrations were found in three individuals only. Older animals had over six times higher concentrations of cadmium in both kidneys and liver than younger individuals. The cadmium content in kidneys increased with animals' age while no such relationship was found for zinc. Although older animals had higher mean concentrations of zinc in kidneys, liver, and muscles, the two age groups did not differ significantly. The mean concentration of zinc in the kidneys of moose studied was 38.83 mg kg^-1, while in the liver it amounted to 29.03 mg kg^-1. The cadmium concentration in the kidneys was significantly correlated with the cadmium concentration in the liver (r = 0.53, p ≤ 0.01) and with the zinc concentration in the kidneys (r = 0.52, p ≤ 0.01). The data obtained within study correspond with analyses results of the organs of healthy moose in Sweden.

Tissue distribution of selenium and effect of season and age on selenium content in roe deer from northwestern Poland

The aim of the study was to compare selenium concentrations in different organs of roe deer from northwestern Poland. Samples of liver, kidneys, heart and lungs, collected from 74 roe deer shot during the hunting seasons of 2008-2009 in northwestern Poland, were studied. Selenium concentration in the organs was determined spectrofluorimetrically. Mean selenium concentration was 0.06 µg/g w.w. in the liver, 0.41 µg/g w.w. in the kidneys and 0.05 µg/g w.w. in the heart and lungs. Season had a significant effect on selenium concentration in the liver, kidneys, lungs and heart. In all the organs, the highest selenium concentration was found in spring and the lowest in autumn and winter. All animals studied were deficient in selenium. The low selenium concentration in the liver or heart can disturb their function, and in the future, it may be a factor contributing to the population decline of roe deer in the northwestern part of Poland.

Cadmium in moose kidney and liver--age and gender dependency, and standardisation for environmental monitoring

In the northern hemisphere moose has been found to be suitable as a monitoring animal for the presence of cadmium in the environment. The metal accumulates mainly in the kidney and the liver, with the rate of accumulation dependent on age and possibly also on gender. Collection of tissue material often results in sample selections with disparate age and gender composition, which makes comparison between different regions and different studies difficult. A previous large scale investigation of metals in kidney and liver from moose in Sweden provided Cd data (n = 3,817 and 3,802, respectively) to further explore the relation between Cd accumulation and age/gender. Based on local averages, the individual deviations were analysed with respect to the factors age and gender resulting in an 'ageing function' for each gender and organ. In addition, estimates of the pure individual variations were obtained; the standard deviations correspond to a factor 1.7-1.9 for the Cd concentration, which indicates that 25-30 samples are needed to give a representative mean value (with RSD approximately 10%). In order to be able to compare results from different studies, all individual results can be transformed to represent a 'standard moose' with respect to age and gender. A comparison along these lines was undertaken between Cd levels in Alaska and Sweden. Finally, a relationship between the Cd levels in kidney and liver was derived, providing at least rough estimates for kidney from liver values (or vice versa).

Levels of As, Cd, Pb, Cu, Se and Zn in bovine kidneys and livers in Jamaica

Paired liver and kidney samples from 100 free-range cattle in different parts of Jamaica were analyzed for essential and non-essential trace elements. We found significant enrichment of elements in the kidney (K) compared to the liver (L) with the K/L concentration ratios being 5.2 for Cd, 4.1 for Pb, 3.5 for Se and 2.1 for As, but the Cu contents of the kidney were significantly higher with the K/L ratio of 0.45. A large number of kidney and liver samples showed Cu concentrations in the ranges that were associated with deficiency effects in mammals. About 15% of the hepatic samples had Zn concentrations below 20 microg/g, suggesting that there might be zinc insufficiency in some of the animals. Positive associations were found between the metals in both the kidney and liver. On average, the intake of Cd from consumption of both bovine kidney and liver from the island was estimated to be 5.2 microg/day, equivalent to about 7% of the provisional tolerable daily intake (PTDI), although anyone who habitually consumed the few kidneys or livers with >40 microg/g cadmium may be at some risk of exceeding the PTDI. The consumption of offal from local animals did not appear to be an important dietary source of any of the essential microelements.

Copper deficiency and neurological disorders in man and animals

Copper metabolism in the brain is far from being completely understood and further studies are needed on the role of copper in the CNS, starting with careful measurements, metal and biological speciation of metabolites on the molecular level, and combining copper concentration in different brain areas with morphological as well as biochemical alteration after Cu-depletion/deficiency. So far a pathological role for copper has been clearly demonstrated in some human genetic diseases (e.g., Menkes' and Wilson's diseases), but other pathological features connected with metal depletion are under investigation in several laboratories. The metabolic interaction between copper and other metal ions in some neurological disorders is also discussed in this contribution.