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1.
Ecotoxicol Environ Saf ; 100: 99-104, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24119654

RESUMO

The North American river otter (Lontra canadensis) is a biomonitor for organohalogenated compounds (OHCs) associated with a wide range of deleterious health effects in wildlife and humans. We determined concentrations of twenty OHCs in livers of 23 river otters salvaged by the Illinois Department of Natural Resources from 2009 to 2011, determined sex-dependent distribution of OHCs, and compared our results to the reported concentrations of four OHCs in Illinois river otters from 1984 to 1989. Since these contaminants have been banned for over 30 years, we predicted smaller mean concentrations than those previously reported in Illinois otters. We detected eleven of twenty OHCs; PCBs (polychlorinated biphenyls), dieldrin, and 4,4'-DDE (dichlorodiphenyldichloroethylene) were present in the greatest mean concentrations. We report the largest mean concentration of dieldrin to date in the liver of North American river otters (mean: 174, range: 14.4-534 parts per billion wet wt [ppb]). Mean PCB concentrations were significantly higher in males (mean: 851; range: 30-3450 ppb) than females (mean: 282; range: 40-850 ppb; p=0.04). Mean concentrations of dieldrin were greater than those detected in otters from 1984 to 1989 (mean: 90; range: 30-130 ppb; p<0.05). Our results suggest OHC exposure remains a concern. Future research in Illinois should focus on evaluating OHCs exposures, particularly dieldrin, at the watershed level.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Fígado/química , Lontras/fisiologia , Rios/química , Poluentes Químicos da Água/análise , Animais , Feminino , Éteres Difenil Halogenados/análise , Illinois , Masculino , Praguicidas/análise , Bifenilos Policlorados/análise , Fatores Sexuais
2.
PLoS One ; 13(9): e0201337, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30235217

RESUMO

BACKGROUND: It is a wide-spread assumption about footbinding that footbound girls and women were more of an economic burden on their families than those never bound. It is often presumed that government policies and missionary campaigns ended footbinding. METHODS/ OBJECTIVES: We use regression and log-likelihood tests, with bootstrapping for confirmation, to analyze which of a series of ethnographically and historically hypothesized variables significantly correlate with footbinding. We also consider an indirect measure of government prohibitions. We analyze two large datasets based on oral surveys with elderly women of the last footbound generations from 12 inland Chinese provinces. CONCLUSIONS: Handicraft production, particularly commercial handicraft production, correlates with whether Chinese girls were subjected to footbinding before 1950. Girlhood knowledge of government prohibitions against footbinding, an indirect measure of awareness by the adults who decided whether to bind a girl's feet, did not correlate with whether women were ever footbound. Spinning cotton thread for commercial purposes (sale, wage, direct exchange) correlated with greater daily production, with great county-level variation in quantity produced. Moreover, Chinese commercial spinners labored more years before marriage than domestic spinners. IMPLICATIONS: Chinese daughters-whether footbound or not-made important economic contributions to rural households, thus suggesting a need to revise our understanding of China's gender and economic history. Further implications of our results are that research is warranted on the assumed efficacy of government prohibitions-in both rural and urban areas-and on the presumption that footbinding among elite Chinese women was unrelated to economic concerns, including handicraft production. The demonstrated economic correlates of footbinding in inland, rural China also suggest a need to reevaluate whether contemporary customs controlling and cloistering girls and women, such as female genital cutting in Africa and the threat of honor killings of girls and women in South Asia, might have economic correlates.


Assuntos
Indústria da Beleza/economia , Bases de Dados Factuais , População Rural , Mulheres Trabalhadoras , China , Feminino , Humanos
3.
Theriogenology ; 94: 71-78, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28407863

RESUMO

Knowledge of reproductive characteristics of wild populations is necessary to inform responsible management decisions that promote herd health. As management, goals, and free-ranging populations change over time and landscapes, updated knowledge of reproductive characteristics are needed to inform responsible management practices. We estimated reproductive characteristics of female white-tailed deer in Illinois, including pregnancy rate, litter size, fetal growth and fetal sex ratio. We found maternal age to have an important influence on several reproductive factors. Approximately 66% of tested females (n = 3884) were pregnant and pregnancy rates increased with increasing maternal age, from 20.5% in fawns to 85.8% in adult deer. Litter size ranged from 1 to 5 fetuses per pregnant female. The average litter size was 1.9 ± 0.54 fetuses per pregnant female and also increased with age, from 1.2 in fawns to 2.0 in adults, respectively. Breeding season peaked in November with the mean estimated conception dates of fetuses varying with maternal age. Fawns conceived fetuses later in the breeding season (December 2) compared to yearlings and adults (November 11 and 8, respectively). We measured the body mass index (BMI) of all fetuses and found that litter size and female age influence fetal size. We found no bias in fetal sex ratio (average 1.0:1.0, male:female) but we observed a sex bias in fetal size (mean BMI male = 0.71, female 0.67) across all maternal age classes. A comparison of the current study and previous reports indicate that variation in maternal age within a population is an important driver of reproductive metrics, likely because maternal age and body size or condition are related. Furthermore, variation in resource availability will influence reproductive rates, especially among fawn females.


Assuntos
Cervos/fisiologia , Reprodução , Animais , Índice de Massa Corporal , Tamanho Corporal , Cruzamento , Feminino , Illinois , Tamanho da Ninhada de Vivíparos , Idade Materna , Gravidez , Taxa de Gravidez , Estações do Ano , Caracteres Sexuais , Razão de Masculinidade
4.
Prion ; 9(1): 48-58, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25695915

RESUMO

Prion proteins (PrP(C)) are cell membrane glycoproteins that can be found in many cell types, but specially in neurons. Many studies have suggested PrP(C)'s participation in metal transport and cellular protection against stress in the central nervous system (CNS). On the other hand PrP(Sc), the misfolded isoform of PrP(C) and the pathogenic agent in transmissible spongiform encephalopathies (TSE), has been associated with brain metal dyshomeostasis in prion diseases. Thus, changes in metal concentration associated with protein misfolding and aggregation have been reported for human and animal prion diseases, as well as for other neurodegenerative disorders, such as Parkinson's and Alzheimer's disease. The use of metal concentrations in tissues as surrogate markers for early detection of TSEs has been suggested. Studies on the accumulation of metals in free-ranging white-tailed deer have not been conducted. This study established concentrations of copper, iron, manganese, and magnesium in 2 diagnostic tissues used for CWD testing (obex and retropharyngeal lymph nodes (RLN)). We compared these concentrations between tissues and in relation to CWD status. We established reference intervals (RIs) for these metals and explored their ability to discriminate between CWD-positive and CWD-negative animals. Our results indicate that independent of CWD status, white-tailed deer accumulate higher concentrations of Fe, Mn and Mg in RLN than in obex. White-tailed deer infected with CWD accumulated significantly lower concentrations of Mn and Fe than CWD-negative deer. These patterns differed from other species infected with prion diseases. Overlapping values between CWD positive and negative groups indicate that evaluation of these metals in obex and RLN may not be appropriate as a diagnostic tool for CWD infection in white-tailed deer. Because the CWD-negative deer were included in constructing the RIs, high specificities were expected and should be interpreted with caution. Due to the low sensitivity derived from the RIs, we do not recommend using metal concentrations for disease discrimination.


Assuntos
Cervos , Linfonodos/metabolismo , Linfonodos/patologia , Metais/metabolismo , Doença de Emaciação Crônica/metabolismo , Doença de Emaciação Crônica/patologia , Animais , Illinois , Modelos Biológicos , Sensibilidade e Especificidade
5.
J Anim Sci Technol ; 56: 16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26290705

RESUMO

Fatty acids (FA) have recently been used in several studies to infer the diet in a number of species. While these studies have been largely successful, most have dealt with predators that have a fairly specialized diet. In this paper, we used FA analysis as a tool to infer the diet of the nearctic river otter (Lontra canadensis). The river otter is an opportunistic predator known to subsist on a wide variety of prey including, fishes, crayfish, molluscs, reptiles and amphibians, among others. We analyzed the principle components of 60 FA from otters and 25 potential prey species in Illinois, USA. Prey species came from 4 major taxonomic divisions: fishes, crayfish, molluscs and amphibians. Within each division, most, but not all, species had significantly different profiles. Using quantitative FA signature analysis, our results suggest that, by mass, fish species are the most significant component of Illinois River otters' diet (37.7 ± 1.0%). Molluscs ranked second (32.0 ± 0.8%), followed by amphibians (27.3 ± 4.3%), and finally, crayfish (3.0 ± 0.6%). Our analysis indicates that molluscs make up a larger portion of the otter diet than previously reported. Throughout much of the Midwest there have been numerous otter reintroduction efforts, many of which appear to be successful. In regions where mollusc species are endangered, these data are essential for management agencies to better understand the potential impact of otters on these species. Our analysis further suggests that quantitative FA signature analysis can be used to infer diet even when prey species are diverse, to the extent that their FA profiles differ. Better understanding of the otter's metabolism of FA would improve inferences of diet from FA analysis.

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