Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Vet Res ; 54(1): 84, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773068

RESUMO

Prion diseases, including chronic wasting disease (CWD) in cervids, are fatal neurodegenerative disorders caused by the misfolding of cellular prion proteins. CWD is known to spread among captive and free-ranging deer in North America. In 2016, an outbreak of contagious CWD was detected among wild reindeer in Norway, marking the first occurrence of the disease in Europe. Additionally, new sporadic forms of CWD have been discovered in red deer in Norway and moose in Fennoscandia. We used serial protein misfolding cyclic amplification to study the ability of Norwegian prion isolates from reindeer, red deer, and moose (two isolates), as well as experimental classical scrapie from sheep, to convert a panel of 16 brain homogenates (substrates) from six different species with various prion protein genotypes. The reindeer CWD isolate successfully converted substrates from all species except goats. The red deer isolate failed to convert sheep and goat substrates but exhibited amplification in all cervid substrates. The two moose isolates demonstrated lower conversion efficacies. The wild type isolate propagated in all moose substrates and in the wild type red deer substrate, while the other isolate only converted two of the moose substrates. The experimental classical scrapie isolate was successfully propagated in substrates from all species tested. Thus, reindeer CWD and classical sheep scrapie isolates were similarly propagated in substrates from different species, suggesting the potential for spillover of these contagious diseases. Furthermore, the roe deer substrate supported conversion of three isolates suggesting that this species may be vulnerable to prion disease.


Assuntos
Cervos , Doenças das Cabras , Doenças Priônicas , Príons , Rena , Scrapie , Doenças dos Ovinos , Doença de Emaciação Crônica , Animais , Ovinos , Príons/genética , Rena/metabolismo , Doenças Priônicas/veterinária , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Doença de Emaciação Crônica/genética , Noruega/epidemiologia , Cabras/metabolismo
3.
J Infect Dis ; 226(5): 933-937, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-33502474

RESUMO

Chronic wasting disease (CWD) is the transmissible spongiform encephalopathy or prion disease affecting cervids. In 2016, the first cases of CWD were reported in Europe in Norwegian wild reindeer and moose. The origin and zoonotic potential of these new prion isolates remain unknown. In this study to investigate zoonotic potential we inoculated brain tissue from CWD-infected Norwegian reindeer and moose into transgenic mice overexpressing human prion protein. After prolonged postinoculation survival periods no evidence for prion transmission was seen, suggesting that the zoonotic potential of these isolates is low.


Assuntos
Cervos , Príons , Rena , Doença de Emaciação Crônica , Animais , Cervos/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Noruega , Príons/genética , Príons/metabolismo , Rena/metabolismo , Doença de Emaciação Crônica/genética
4.
Commun Biol ; 4(1): 1170, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620965

RESUMO

Reindeer (Rangifer tarandus) are semi-domesticated animals adapted to the challenging conditions of northern Eurasia. Adipose tissues play a crucial role in northern animals by altering gene expression in their tissues to regulate energy homoeostasis and thermogenic activity. Here, we perform transcriptome profiling by RNA sequencing of adipose tissues from three different anatomical depots: metacarpal (bone marrow), perirenal, and prescapular fat in Finnish and Even reindeer (in Sakha) during spring and winter. A total of 16,212 genes are expressed in our data. Gene expression profiles in metacarpal tissue are distinct from perirenal and prescapular adipose tissues. Notably, metacarpal adipose tissue appears to have a significant role in the regulation of the energy metabolism of reindeer in spring when their nutritional condition is poor after winter. During spring, genes associated with the immune system are upregulated in the perirenal and prescapular adipose tissue. Blood and tissue parameters reflecting general physiological and metabolic status show less seasonal variation in Even reindeer than in Finnish reindeer. This study identifies candidate genes potentially involved in immune response, fat deposition, and energy metabolism and provides new information on the mechanisms by which reindeer adapt to harsh arctic conditions.


Assuntos
Adaptação Biológica/genética , Tecido Adiposo/metabolismo , Rena/genética , Transcriptoma , Animais , Regiões Árticas , Finlândia , Rena/metabolismo , Estações do Ano , Sibéria
5.
Int J Circumpolar Health ; 80(1): 1897222, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33704030

RESUMO

Wild game consumption has been associated with health benefits but the acute influence on human protein metabolism remains unknown. We compared feeding-induced responses of equivalent amounts of free-range reindeer (FR) and commercial beef (CB) on protein kinetics using stable isotope methodology. Seven participants (age: 40 ± 14 years; body mass index: 24 ± 3 kg/m2) completed two randomised studies, ingesting 2 oz of FR or CB. L-[ring 2H5]phenylalanine & L-[ring 2H2]tyrosine were delivered via primed, continuous intravenous infusion. Blood samples were collected during the basal period and following consumption of FR or CB. Feeding-induced changes in whole-body protein synthesis (PS), protein breakdown (PB), and net protein balance (NB) were determined via plasma sample isotope enrichment analysis by gas chromatography-mass spectrometry; plasma essential amino acid (EAA) concentrations were determined by liquid chromatography-electrospray ionisation-mass spectrometry. Plasma post-prandial EAA concentrations were higher with FR compared to CB (P < 0.05). The acute feeding-induced PS response was not different, but PB was reduced and contributed to a superior level of NB (P < 0.00001) in FR compared to CB. Our results demonstrate that FR may influence more favourable protein metabolism than CB. These data support potential health benefits of wild game onf whole-body protein.Abbreviations: BMI: body mass index; DIAAS: digestible indispensable amino acid score; CB: commercial beef; EAA: essential amino acids; FR: free-range reindeer; Ra: rate of appearance; UAF: University of Alaska Fairbanks; USDA: USA Department of Agriculture.


Assuntos
Rena , Aminoácidos Essenciais/metabolismo , Animais , Índice de Massa Corporal , Bovinos , Humanos , Período Pós-Prandial , Biossíntese de Proteínas , Rena/metabolismo , Estados Unidos
6.
Chemosphere ; 245: 125458, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31846790

RESUMO

Reindeers play an important role in the polar ecosystem, being long-lived sole vegetarians feeding on local vegetation. They can be used as a valuable bioindicator, helping us to understand contaminants' impact on the polar terrestrial ecosystem. Still, scarce data exist from research in which polar herbivores (especially those from the European parts of the Arctic) were a major study subject for trace elements and persistent organic pollutant determination. Here, Svalbard reindeer fur has been used to determine metals, non-metals and metalloids using ICP-MS, and several persistent organic pollutants including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) using gas chromatography coupled to a tandem mass spectrometer (GC-MS/MS). Samples were collected from reindeer populations living in the area near Ny-Ålesund and Longyearbyen. Essential elements like Fe, Mg, Zn, K, Ca, Cu predominated in the trace elements profile. Median values of As, Cd, Co, Li, Ni, Se and V were all below 0.5 µg/g dw. Mercury was below detection limit in all samples, while the Pb median varied from 0.35 to 0.74 µg/g dw. Except acenaphthylene and fluorene, PAHs were detectable only in samples collected in the vicinity of Longyearbyen. Of 15 studied pesticides, only DDT and its metabolites were above the detection limit, and, of PCBs, only PCB28.


Assuntos
Pelo Animal/química , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Animais , Regiões Árticas , Ecossistema , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rena/metabolismo , Svalbard , Espectrometria de Massas em Tandem , Oligoelementos/análise
7.
Sci Total Environ ; 687: 1337-1343, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412467

RESUMO

Models and approaches have been developed to predict radiation exposure of wildlife under field conditions. However, there have been few attempts to directly measure radiation exposure of wildlife in the field and confirm the doses predicted by models. This is a potential issue for stakeholder acceptance of modelling-based assessments. Here is presented a comprehensive study comparing the results of different dosimeters fitted to free-ranging reindeer inhabiting an area that received comparatively high radiocaesium deposition from the 1986 Chernobyl accident. The external dose of reindeer was measured using the four dosimeter types in aluminium box mounted on the GPS collar. The measurements were compared with two model predictions: (i) external dose to reindeer across the entire range area of the herd; and (ii) external doses of individual reindeer predicted using GPS tracking data to determine locations. It was found that although significant differences between the estimates of the various dosimeters were found these were small with no practical implication. Also, the mean predicted external doses using the GPS tracking data were not significantly different to estimates from two of the four passive dosimeter results. The average external dose predicted across the herd area was significantly lower than doses recorded by the dosimeters and also estimates using GPS data to determine reindeer location (and hence exposure). For 137Cs the average external dose from the GPS tracking data was about twice that predicted across the herd area, because collared animals favoured the more contaminated area of the study site. This suggests that in some circumstances the assumption of averaging contamination over an assumed home range within assessments may be inadequate though this would need to be balanced against other uncertainties. Natural radiation was the greatest contribution to reindeer exposure and a function of the high altitude.


Assuntos
Radioisótopos de Césio/metabolismo , Exposição à Radiação/análise , Monitoramento de Radiação , Cinza Radioativa , Poluentes Radioativos/metabolismo , Rena/metabolismo , Animais , Humanos , Noruega , Exposição à Radiação/estatística & dados numéricos
8.
Science ; 364(6446)2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31221829

RESUMO

The reindeer is an Arctic species that exhibits distinctive biological characteristics, for which the underlying genetic basis remains largely unknown. We compared the genomes of reindeer against those of other ruminants and nonruminant mammals to reveal the genetic basis of light arrhythmicity, high vitamin D metabolic efficiency, the antler growth trait of females, and docility. We validate that two reindeer vitamin D metabolic genes (CYP27B1 and POR) show signs of positive selection and exhibit higher catalytic activity than those of other ruminants. A mutation upstream of the reindeer CCND1 gene endows an extra functional binding motif of the androgen receptor and thereby may result in female antlers. Furthermore, a mutation (proline-1172→threonine) in reindeer PER2 results in loss of binding ability with CRY1, which may explain circadian arrhythmicity in reindeer.


Assuntos
Adaptação Biológica , Chifres de Veado/crescimento & desenvolvimento , Ritmo Circadiano/fisiologia , Rena/genética , Rena/fisiologia , Motivos de Aminoácidos/genética , Substituição de Aminoácidos , Animais , Regiões Árticas , Sítios de Ligação/genética , Ritmo Circadiano/genética , Ciclina D1/genética , Feminino , Proteínas Circadianas Period/genética , Prolina/genética , Rena/metabolismo , Treonina/genética , Vitamina D/metabolismo
9.
Environ Sci Pollut Res Int ; 25(36): 36693-36701, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30377969

RESUMO

During both winter and summer, Svalbard reindeer selectively feed on different types of vegetation that are not only a source of nutritional value, but also a place of heavy metal accumulation. In the present study, the content of cadmium, chromium, copper, iron, lead, nickel, manganese, and zinc in reindeer excrement was measured. The main aims were to determine the seasonal content of several heavy metals in Svalbard reindeer faeces, and to compare their values in terms of dietary preferences during the year. Summer and winter reindeer excrement was gathered along a designated linear transect running through Bolterdalen and the vegetation described on 1 m2 plots. All of the analysed heavy metals were detected in the reindeer faeces and this fact seems to be connected with the incomplete content of these elements in an animal's tissue after forage digestion. Analysis showed differences between summer and winter excrement in terms of concentrations of cadmium, chromium, iron, and nickel, but no differences were found for the other four elements analysed (manganese, lead, zinc, and copper). However, concentrations of heavy metals in faeces are rather low in comparison with both the levels in the vegetation that may be grazed by reindeer and in reindeer tissue.


Assuntos
Exposição Dietética/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Fezes/química , Metais Pesados/análise , Rena/metabolismo , Animais , Estações do Ano , Svalbard
10.
Chemosphere ; 203: 209-218, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29621677

RESUMO

Over the years, noticeable effort has been directed towards contaminant determination in multiple biotic samples collected from the inhabitants of the Arctic. Little consideration has been given to polar herbivores, however, especially those from the European parts of the Arctic. To provide a broader perspective, we aimed to decipher trace element concentration in hairs of the key species in the Arctic, namely the Svalbard reindeer (Rangifer tarandus platyrhynchus), and to recognise whether diet variations could correspond with forward exposure. The effect of habitat and diet was investigated using the ratios of stable isotopes of carbon (δ13C) and nitrogen (δ15N), and previous literature studies on vegetation from the areas of interest. Analysis was performed for eighteen elements in total, both toxic and essential. Metals were present in a decreasing order Fe > Zn > Ba > Cu > Pb > Cr > Ni > V > Ga =La > Rb > As > Li > Co > Hg > Cd > Cs > Be. Similarity in trends in the studied subpopulations was observed for many metals. A significant log-linear correlation was observed for most of the elements, excluding nitrogen and carbon isotopes signature. Extremely high iron levels were determined in some of the samples, suggesting past iron overload. Zinc, in contrast to the remaining metals, did not correlate well with any other element. Mercury was determined at very low levels, in accordance with previous literature regarding its concentrations in moss and lichen species in Svalbard. The analysis of stable isotopes showed a high variation in nitrogen isotopes signatures. Further research is required to properly evaluate the potential health risks and ecological implications of elevated exposure.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Rena/metabolismo , Oligoelementos/análise , Animais , Regiões Árticas , Isótopos de Carbono/análise , Dieta , Líquens/química , Isótopos de Nitrogênio/análise , Svalbard
11.
Pol J Vet Sci ; 21(1): 55-64, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29624010

RESUMO

Ghrelin is a novel growth hormone (GH)-releasing peptide, which has been identified as an endogenous ligand for the GH-sretagogue receptor. The sequence and expression of ghrelin has been determined in many species. In this study, to reveal the molecular characterization and expression patterns of ghrelin in the reindeer (Rangifer tarandus), the full-length DNA and cDNA encoding ghrelin were cloned from reindeer stomach using genome walking and rapid amplification of complementary deoxyribonucleic acid ends (RACE). The expression of ghrelin in almost all tissues was examined by real-time quantitative PCR (RT-qPCR). The 4076 bp amplicon of the ghrelin gene consisting of 4 exons and 3 introns was cloned from reindeer. Results of cDNA cloning and sequence analysis revealed that the full-length ghrelin cDNA was composed of 539 bp that included a 5'-untranslated region (46 bp), an open reading frame (ORF) (351 bp), and a 3'-untranslated region (142 bp). In addition, ghrelin was expressed in the all tissues examined, with the expression in the abomasum significantly higher than that in other tissues (p<0.05), followed by the pancreas, duodenum, testis and oesophagus. The results show that the expression of ghrelin in the reindeer gastrointestinal tract is extensive, suggesting its may have a role in regulating the digestive function.


Assuntos
Regulação da Expressão Gênica/fisiologia , Grelina/metabolismo , Rena/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , Grelina/química , Grelina/genética , Masculino , Rena/genética , Especificidade da Espécie
12.
Sci Total Environ ; 554-555: 329-36, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26956180

RESUMO

Two caribou populations in West Greenland were sampled and the kidneys, liver and muscle analyzed for contaminants, including aluminum, arsenic, cadmium, copper, lead, mercury, selenium and zinc. Although close in proximity, the two populations are topographically separated by an ice cap, which creates different climates and vegetation types in each region. Contaminant levels reflected the differing diets of the two caribou populations. To the south in the wetter lichen-rich region, caribou had significantly more aluminum, arsenic, cadmium, lead, mercury, selenium and zinc, likely due to atmospheric deposition on lichens. To the north in the dry desert steppe where grasses predominate, caribou had higher levels of copper. Cows collected in late winter had significantly less hepatic copper, lead and mercury if pregnant, indicating placental transfer of these elements. Our results suggest that hepatic copper levels <200 µg g(-1) dry weight may result in copper depletion in pregnant cows and hepatic mercury concentrations above 0.5 µg g(-1) dry weight may negatively affect fertility in caribou cows. Hepatic mercury levels were negatively correlated with cow body weight, suggesting an adverse effect on body condition. Element concentrations found in tissues from these caribou are not considered to be of a health concern for those consuming this traditional food.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Metais Pesados/metabolismo , Rena/metabolismo , Animais , Arsênio/metabolismo , Cádmio/metabolismo , Cobre/metabolismo , Groenlândia , Chumbo/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Zinco/metabolismo
13.
Acta Vet Scand ; 56: 76, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25421461

RESUMO

BACKGROUND: Overwintering (breeding) reindeer (Rangifer tarandus tarandus) are commonly treated with ivermectin against parasitic infestations once yearly in autumn-winter roundups. The only preparations registered to reindeer are those for subcutaneous injection. However, also oral extra-label ivermectin administration is used. Twenty-six, 8-month-old reindeer calves were randomly allocated into three groups. Group 1 (n = 9) received oral ivermectin mixture (Ivomec® vet mixt. 0.8 mg/ml, oral ovine liquid drench formulation), Group 2 (n = 9) oral ivermectin paste (Ivomec® vet 18.7 mg/g equine paste), and Group 3 (n = 8) subcutaneous injection of ivermectin (Ivomec® 10 mg/ml vet inj.), each group at a dose of 200 µg/kg body weight. Blood samples were collected at treatment and at days 1, 2, 3, 6, 9 and 16 post treatment. Plasma concentrations of ivermectin were determined by high-pressure liquid chromatography (HPLC) with fluorescence detection. RESULTS: The peak plasma concentration (Cmax) was reached by 2 days after each treatment. The Cmax and Area Under Curve (AUC) differed significantly between the groups: Cmax was 30.2 ± 3.9, 14.9 ± 5.7 and 63.1 ± 13.1 ng/ml, and AUC∞ was 2881 ± 462, 1299 ± 342 and 6718 ± 1620 ng*h/ml for groups 1, 2 and 3, respectively (mean ± standard deviation). CONCLUSIONS: The differences in plasma concentrations of ivermectin are concomitant with earlier observed differences in antiparasitic efficacy, which discounts the use of the equine paste in reindeer in favour of the oral ovine liquid drench formulation, or preferably, the reindeer-registered subcutaneous injection formulation.


Assuntos
Anti-Helmínticos/farmacocinética , Ivermectina/farmacocinética , Rena/metabolismo , Administração Oral , Animais , Anti-Helmínticos/sangue , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão/veterinária , Feminino , Injeções Subcutâneas/veterinária , Ivermectina/sangue , Masculino
14.
PLoS One ; 9(8): e103471, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25102057

RESUMO

Winter severity can influence large herbivore populations through a reduction in maternal proteins available for reproduction. Nitrogen (N) isotopes in blood fractions can be used to track the use of body proteins in northern and montane ungulates. We studied 113 adult female caribou for 13 years throughout a series of severe winters that reduced population size and offspring mass. After these severe winters, offspring mass increased but the size of the population remained low. We devised a conceptual model for routing of isotopic N in blood in the context of the severe environmental conditions experienced by this population. We measured δ15N in three blood fractions and predicted the relative mobilization of dietary and body proteins. The δ 15N of the body protein pool varied by 4‰ and 46% of the variance was associated with year. Annual variation in δ15N of body protein likely reflected the fall/early winter diet and winter locations, yet 15% of the isotopic variation in amino acid N was due to body proteins. Consistent isotopic differences among blood N pools indicated that animals tolerated fluxes in diet and body stores. Conservation of body protein in caribou is the result of active exchange among diet and body N pools. Adult females were robust to historically severe winter conditions and prioritized body condition and survival over early investment in offspring. For a vagile ungulate residing at low densities in a predator-rich environment, protein restrictions in winter may not be the primary limiting factor for reproduction.


Assuntos
Nitrogênio/sangue , Rena/metabolismo , Estações do Ano , Alaska , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Temperatura Baixa , Proteínas Alimentares/metabolismo , Feminino , Nitrogênio/química , Densidade Demográfica , Dinâmica Populacional , Análise de Regressão , Rena/anatomia & histologia , Rena/fisiologia , Reprodução , Neve
15.
Environ Toxicol Chem ; 33(9): 1956-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24975230

RESUMO

The bioaccumulation of current use pesticides (CUPs) and stable isotopes of carbon and nitrogen were investigated in vegetation-caribou-wolf food chain in the Bathurst region (Nunavut, Canada). Volumetric bioconcentration factors (BCF(v)) in vegetation were generally greatest for dacthal (10-12) ≥ endosulfan sulfate (10-11) > ß-endosulfan (>9.0-9.7) ≥ pentachloronitrobenzene (PCNB; 8.4-9.6) > α-endosulfan (8.3-9.3) > chlorpyrifos (8.0-8.7) >chlorothalonil (7.6-8.3). The BCF(v) values in vegetation were significantly correlated with the logarithm of the octanol-air partition coefficients (log K(OA)) of CUPs (r(2) = 0.90, p = 0.0040), although dacthal was an outlier and not included in this relationship. Most biomagnification factors (BMFs) for CUPs in caribou:diet comparisons were significantly less than 1. Similarly, the majority of wolf:caribou BMFs were either significantly less than 1 or were not statistically greater than 1. Significant trophic magnification factors (TMFs) were all less than 1, indicating that these CUPs exhibit trophic dilution through this terrestrial food chain. The log K(OA) reasonably predicted bioconcentration in vegetation for most CUPs but was not correlated with BMFs or TMFs in mammals. Our results, along with those of metabolic studies, suggest that mammals actively metabolize these CUPs, limiting their biomagnification potential despite entry into the food chain through effective bioconcentration in vegetation.


Assuntos
Cadeia Alimentar , Praguicidas/análise , Rena/metabolismo , Lobos/metabolismo , Animais , Regiões Árticas , Canadá , Endossulfano/análogos & derivados , Endossulfano/análise , Endossulfano/metabolismo , Monitoramento Ambiental , Nunavut , Praguicidas/metabolismo , Ácidos Ftálicos/análise , Ácidos Ftálicos/metabolismo
16.
Sci Total Environ ; 476-477: 125-35, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24463250

RESUMO

A study concerning persistent organic pollutants in Finnish semi-domesticated reindeer was conducted in northern Finland. The aim of this study was to explore POP presence in different tissues of reindeer. In addition, it was studied how POPs are transported from food concentrates and lichen to reindeer hind tissues and further to the placenta, foetus, milk and calf. Concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs), 37 polychlorinated biphenyls (PCBs) (including 12 dioxin-like PCBs), and 15 polybrominated diphenyl ethers (PBDEs) were analysed. In most of the reindeer muscle tissue samples PCBs were clearly dominating compounds (on average 58% of the total WHO-TEQ). The total WHO-TEQ was higher in the muscle tissue of reindeer calves than in their corresponding hinds (on average 1.7 pg/g fat vs. 1.1 pg/g fat, respectively). The total WHO-TEQ concentrations were higher in the muscle and liver tissues of reindeer hinds than in their blood or placentas. The foetuses had clearly lower WHO-TEQ concentrations than their corresponding hinds. The contribution of WHO-PCDD/F-TEQ to the total WHO-TEQ was somewhat higher in the liver than in the muscle tissue. The reindeer hind-calf pair, which had gone through the lichen diet, had on average higher WHO-PCDD/F- and PCB-TEQ concentrations in their tissues than the hind-calf-pair that had gone through the reindeer food concentrate diet. WHO-PCB-TEQs in the reindeer foetuses were equal with the concentrations of placentas. The reindeer foetuses contained generally more PBDEs than their corresponding hinds and placentas. This may indicate effective transport of these compounds through the placenta of reindeer.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Rena/metabolismo , Animais , Benzofuranos/análise , Benzofuranos/metabolismo , Dibenzofuranos Policlorados , Poluentes Ambientais/análise , Feminino , Feto , Finlândia , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Líquens/química , Leite/metabolismo , Placenta/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/metabolismo , Gravidez
17.
Microb Ecol ; 66(4): 840-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23959114

RESUMO

Highly cellulolytic bacterial species such as Ruminococcus flavefaciens are regarded essential for the microbial breakdown of cellulose in the rumen. We have investigated the effect of ruminal dosing of R. flavefaciens strain 8/94-32 during realimentation of starved reindeer (males, n = 3). Microbiome function measured as in situ digestion of cellulose and food pellets (percent DMD; dry matter disappearance) decreased after probiotic dosing. Microbial community analyses (>100,000 16S rDNA gene sequences for 27 samples) demonstrated that ruminal dosing influenced the microbiome structure; reflected by increased phylogenetic distances from background samples (unweighted UniFrac analysis) and reduced species diversity and evenness. Despite the inability to detect strain 8/94-32 post-dosing, the relative abundance of its affiliate family Ruminococcaceae remained consistent throughout the trial, whilst a dominant peak in the genus Prevotella and decline in uncharacterized Bacteroidetes (uBacNR) were observed in treatment samples. No clear relationships were observed between the relative abundance of Ruminococcaceae, Prevotella and uBacNR with cellulose DMD; however, Prevotella (negative) and uBacNR (positive) exhibited relationships with pellet DMD. These unexpected effects of ruminal dosing of a cellulolytic bacterium on digestibility are relevant for other studies on rumen manipulation.


Assuntos
Bactérias/isolamento & purificação , Microbiota , Probióticos/administração & dosagem , Rúmen/microbiologia , Ruminococcus/fisiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Celulose/metabolismo , Digestão , Masculino , Dados de Sequência Molecular , Filogenia , Rena/metabolismo , Rena/microbiologia , Rúmen/metabolismo
18.
Anat Rec (Hoboken) ; 295(10): 1660-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22907891

RESUMO

We performed a systematic characterization of the hepatic vitamin A storage in mammals and birds of the Svalbard Archipelago and Greenland. The liver of top predators, including polar bear, Arctic fox, bearded seal, and glaucous gull, contained about 10-20 times more vitamin A than the liver of all other arctic animals studied, as well as their genetically related continental top predators. The values are also high compared to normal human and experimental animals like mouse and rat. This massive amount of hepatic vitamin A was located in large autofluorescent lipid droplets in hepatic stellate cells (HSCs; also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells, or Ito cells). The droplets made up most of the cells' cytoplasm. The development of such an efficient vitamin A-storing mechanism in HSCs may have contributed to the survival of top predators in the extreme environment of the arctic. These animals demonstrated no signs of hypervitaminosis A. We suggest that HSCs have capacity to take-up and store large amounts of vitamin A, which may play a pivotal role in maintenance of the food web, food chain, biodiversity, and eventually ecology of the arctic.


Assuntos
Células Estreladas do Fígado/química , Células Estreladas do Fígado/metabolismo , Comportamento Predatório/fisiologia , Vitamina A/química , Vitamina A/metabolismo , Animais , Regiões Árticas , Charadriiformes/metabolismo , Rena/metabolismo , Focas Verdadeiras/metabolismo , Especificidade da Espécie , Sobrevida/fisiologia , Ursidae/metabolismo
19.
PLoS One ; 7(6): e39055, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22723928

RESUMO

Chronic wasting disease (CWD), a transmissible spongiform encephalopathy of cervids, remains prevalent in North American elk, white-tailed deer and mule deer. A natural case of CWD in reindeer (Rangifer tarandus tarandus) has not been reported despite potential habitat overlap with CWD-infected deer or elk herds. This study investigates the experimental transmission of CWD from elk or white-tailed deer to reindeer by the oral route of inoculation. Ante-mortem testing of the three reindeer exposed to CWD from white-tailed deer identified the accumulation of pathological PrP (PrP(CWD)) in the recto-anal mucosa associated lymphoid tissue (RAMALT) of two reindeer at 13.4 months post-inoculation. Terminal CWD occurred in the two RAMALT-positive reindeer at 18.5 and 20 months post-inoculation while one other reindeer in the white-tailed deer CWD inoculum group and none of the 3 reindeer exposed to elk CWD developed disease. Tissue distribution analysis of PrP(CWD) in CWD-affected reindeer revealed widespread deposition in central and peripheral nervous systems, lymphoreticular tissues, the gastrointestinal tract, neuroendocrine tissues and cardiac muscle. Analysis of prion protein gene (PRNP) sequences in the 6 reindeer identified polymorphisms at residues 2 (V/M), 129 (G/S), 138 (S/N) and 169 (V/M). These findings demonstrate that (i) a sub-population of reindeer are susceptible to CWD by oral inoculation implicating the potential for transmission to other Rangifer species, and (ii) certain reindeer PRNP polymorphisms may be protective against CWD infection.


Assuntos
Rena/metabolismo , Doença de Emaciação Crônica/transmissão , Sequência de Aminoácidos , Animais , Códon , Suscetibilidade a Doenças , Dados de Sequência Molecular , Fases de Leitura Aberta , Polimorfismo Genético , Príons/química , Príons/genética , Príons/metabolismo , Alinhamento de Sequência , Doença de Emaciação Crônica/diagnóstico
20.
Environ Sci Technol ; 45(20): 8665-73, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21905660

RESUMO

The biomagnification behavior of perfluorinated carboxylates (PFCAs) and perfluorinated sulfonates (PFSAs) was studied in terrestrial food webs consisting of lichen and plants, caribou, and wolves from two remote northern areas in Canada. Six PFCAs with eight to thirteen carbons and perfluorooctane sulfonate (PFOS) were regularly detected in all species. Lowest concentrations were found for vegetation (0.02-0.26 ng/g wet weight (ww) sum (Σ) PFCAs and 0.002-0.038 ng/g ww PFOS). Wolf liver showed highest concentrations (10-18 ng/g ww ΣPFCAs and 1.4-1.7 ng/g ww PFOS) followed by caribou liver (6-10 ng/g ww ΣPFCAs and 0.7-2.2 ng/g ww PFOS). Biomagnification factors were highly tissue and substance specific. Therefore, individual whole body concentrations were calculated and used for biomagnification and trophic magnification assessment. Trophic magnification factors (TMF) were highest for PFCAs with nine to eleven carbons (TMF = 2.2-2.9) as well as PFOS (TMF = 2.3-2.6) and all but perfluorooctanoate were significantly biomagnified. The relationship of PFCA and PFSA TMFs with the chain length in the terrestrial food chain was similar to previous studies for Arctic marine mammal food web, but the absolute values of TMFs were around two times lower for this study than in the marine environment. This study demonstrates that challenges remain for applying the TMF approach to studies of biomagnification of PFCAs and PFSAs, especially for terrestrial animals.


Assuntos
Fluorocarbonos/metabolismo , Cadeia Alimentar , Líquens/metabolismo , Rena/metabolismo , Lobos/metabolismo , Ácidos Alcanossulfônicos/metabolismo , Animais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...