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Demographic parameters of the European hare (Lepus europaeus) in southern Australia were investigated by dissecting hares shot by hunters during each month of the year. Gender, body weight, age, sucking, lactation, weight of the abdominal alimentary canal, weight of the left peri-renal fat body, pregnancy status, presence and counts of placental scars, litter size, and stage of gestation were recorded. From those data, growth rates, age at weaning, age and weight at puberty, date of conception, projected birth date, recruitment, survivorship, and the relationships between lactation and fat stores and alimentary capacity were determined.Fecundity of the southern Australian hares followed the seasonal pattern reported for northern hemisphere populations. However, output was lower per female and particularly per older female. Females began breeding at an earlier age such that recruitment into the southern Australian population was more dependent on females in their first year of life than on older females. Growth rates were comparable with European rates. Although high chill factors were apparently associated with higher leveret mortality, there was paradoxically higher overall mortality during the spring-early summer period of higher plant growth than in the late summer–winter period of lower plant growth and more extreme weather conditions. Fat was accumulated during pregnancy and would act as a buffer against the possibility of inadequate food availability during lactation, but hares increased the capacity of the alimentary canal during lactation and presumably with it their ability to assimilate energy to meet the demands of lactation. 相似文献
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An analysis of pollen loads of Apis mellifera was performed in order to identify the pollen sources that support the hives in the Andean region of Chubut. During the apicultural period (from 9 September 2010 to 12 March 2011), pollen loads were collected every fortnight in a selected apiary located in a transition area between the sub-Antarctic forests and the Patagonian steppe. Forty-six pollen types belonging to 26 plant families were found in the pollen spectrum of pollen loads, of which the most diverse were Asteraceae (11 types) and Fabaceae (six types). Families with major biomass contribution were Asteraceae (49%), Fabaceae (10%), Salicaceae (10%), Rhamnaceae (7%), Rosaceae (7%) and Brassicaceae (4%). Thirty-one per cent of the identified pollen belonged to the native flora. The major contribution of indigenous species occurred in late spring. Mutisia spp., Discaria type, Senecio spp., Adesmia spp. and Maytenus spp. were the most collected native taxa. Most plants providing pollen to the beehive are also nectariferous resources in the Andean region of Chubut. The protein content of the collected pollen ranged from 7.78% to 32.48%. The most collected types had protein content between 13.09% and 30.93%. 相似文献
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E. Jean Brennan 《Zoo biology》1989,8(1):37-47
Survival and fertility rates of captive De Bràzza's guenons (Cercopithecus neglectus), based on the 575 known captive animals in 70 zoos and institutions worldwide, were calculated. The results suggest that the high level of infant mortality (males: dx(day 1-yr 1) = 0.73 males; females; dx(day 1-yr 1) = 0.51), low fertility rate (Σ m′x = 1.69), and differential mortality due to the incidence of stillbirths (males: dx(day 1) = 0.676, females: dx(day 1) = 0.442) may threaten the viability of this population. Possible causes of differential mortality rates are discussed and questions requiring additional research are identified. 相似文献
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《Journal of applied animal welfare science : JAAWS》2013,16(3):201-210
The last decade has seen an increased awareness concerning links between violence to nonhuman animals and violence to humans. This has resulted in a number of cross-reporting initiatives between family service providers and animal welfare organizations. The success of these initiatives rests on individuals being willing to report such violence. Thus, there is a need to determine which variables influence an individual's willingness to report deliberate animal cruelty and abuse. The aim of this study was to examine demographic and attitudinal variables to ascertain their impact on propensity to report deliberate animal harm. A telephone questionnaire resulted in 1,208 valid responses from members of the general community. Results showed a number of variables that affected the propensity to report: gender, occupation, and acknowledgment of the link between family violence and deliberate animal harm. This article discusses these variables and their implications. 相似文献
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Vast records of our everyday interests and concerns are being generated by our frequent interactions with the Internet. Here, we investigate how the searches of Google users vary across U.S. states with different birth rates and infant mortality rates. We find that users in states with higher birth rates search for more information about pregnancy, while those in states with lower birth rates search for more information about cats. Similarly, we find that users in states with higher infant mortality rates search for more information about credit, loans and diseases. Our results provide evidence that Internet search data could offer new insight into the concerns of different demographics. 相似文献
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Matthew A. Christensen Laura Bettencourt Leanne Kaye Sai T. Moturu Kaylin T. Nguyen Jeffrey E. Olgin Mark J. Pletcher Gregory M. Marcus 《PloS one》2016,11(11)
BackgroundSmartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality.AimsThe aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep.MethodsWe performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index–PSQI) were obtained by survey. Linear regression was used to obtain effect estimates.ResultsTotal screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency.ConclusionsThese findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep. 相似文献
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Serafín Gutiérrez Ga?l Thébaud Darci R. Smith Joan L. Kenney Scott C. Weaver 《Journal of virology》2015,89(7):4020-4022
The within-host diversity of virus populations can be drastically limited during between-host transmission, with primary infection of hosts representing a major constraint to diversity maintenance. However, there is an extreme paucity of quantitative data on the demographic changes experienced by virus populations during primary infection. Here, the multiplicity of cellular infection (MOI) and population bottlenecks were quantified during primary mosquito infection by Venezuelan equine encephalitis virus, an arbovirus causing neurological disease in humans and equids. 相似文献
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We examined how population density, winter weather, snow conditions, and 2 large-scale climatic indices (North Atlantic Oscillation, NAO, and Arctic Oscillation, AO) influenced demography (reproduction and mortality) in an alpine herd of semi-domesticated reindeer Rangifer tarandus between 1959 and 2000 in Finnish Lapland. The herd lived on heavily grazed lichen pastures, with winter densities between 0.8 and 3.9 individuals km−2 . Icing conditions occurred every 7th yr, on an average, and decreased reproductive rate (calves/females) by 49%. In general linear models icing remarkably increased the fit of snow models to reproductive rate. Incorporation of an interaction term between icing and the snow depth index provided better fit than a model without interaction. Delayed snowmelt decreased reproductive rate. For the day of snowmelt, however, the model without interaction was better than the interaction model. These 3 models provided the best fit to the data and accounted for 51–54% of the variation in reproductive rate. Winter mortality was related to density and large-scale climatic indices, but not to local winter weather except a slight increase in mortality during an icing winter. The best model for winter mortality, including reindeer density and NAO, accounted for 26% of variation in mortality. Three factors may be involved explaining weak density dependence or the lack of such dependence; climate change scenarios that predict higher winter temperature, more frequent thawing-freezing periods, and deeper snow would be expected to decrease reproductive rate and increase winter mortality of reindeer and thus to reduce profitability of reindeer husbandry. In contrast, early springs would be advantageous for reindeer in the short term. 相似文献
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Scott A. Elias 《Journal of the history of biology》2014,47(2):213-242
Systematic entomology flourished as a branch of Natural History from the 1750s to the end of the nineteenth century. During this interval, the “era of Heroic Entomology,” the majority of workers in the field were dedicated amateurs. This article traces the demographic and occupational shifts in entomology through this 150-year interval and into the early twentieth century. The survey is based on entomologists who studied beetles (Coleoptera), and who named sufficient numbers of species to have their own names abbreviated by subsequent taxonomists. In the eighteenth century, 27 entomologists achieved this level of prominence, of whom 37% were academics, 19% were doctors, 11% had private incomes, 19% were clergymen, and 8% were government officials. Many of those with private incomes were members of the European aristocracy, and all but one were European men. The nineteenth century list included 192 entomologists, of whom 17% were academics, 16% were museum curators, 2% were school teachers, 15% were doctors, 6% were military men, 7% were merchants, 2% were government entomologists, 6% had private incomes, 5% were clergymen, 5% were government officials, and 4% were lawyers. The demographics of entomology shifted dramatically in the nineteenth century. Whereas many of the noteworthy entomologists of the eighteenth century were German, Swedish, or French, in the nineteenth century, many more European countries are represented, and almost one-fifth of the noteworthy entomologists were from the United States. The nineteenth century list, like the eighteenth century list, contains no women. By the twentieth century, 63% of 178 noteworthy systematic entomologists were paid professionals, teaching entomology courses in universities, or studying insect taxonomy in museums and government-sponsored laboratories. Only one person on the twentieth century list had a private income, but women (ten individuals) were included on the list for the first time. 相似文献
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S. P. Kharitonov 《Biology Bulletin》2017,44(8):998-1006
A new method for assessing the annual mortality rate in bird populations is described. Ring recoveries from birds that died from various causes serve as the basis for such an assessment. The commonly accepted technique for such an assessment performed with the help of MARK software is laborious, yet fails to ensure a highly precise assessment. To calculate the mortality rate, we propose an exponential demographic model that is based on the geometric progression of a decrease in the annual numbers in some arbitrarily selected set of birds in a population. The equation of the model allows calculating the annual mortality rate of a bird population or even a species in a simple way, if the ringing data covers a vast area, for example, the territory of Russia. In addition, the proposed equation permits producing “a mortality pattern,” namely, to present a chart of interrelations between the theoretical and real rates of the decrease in numbers in a given cohort of birds. The interrelations between the theoretical and real annual mortality rates allow understanding the status of a bird population each year during a period of ringing and recovery collecting: this makes it possible to reveal the population trend about whether the population is stable or decreasing or increasing in numbers. 相似文献
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ABSTRACT: BACKGROUND: The population of dogs and cats passing through rescue shelters may be subject to compromised welfare and increased susceptibility to disease. Little information exists to describe this population, its dynamics and associated management practices. The aim of this study was to carry out a census of un-owned cats and dogs in the UK in 2010, and to document the origins, destinations, husbandry and costs associated with the care of these animals. RESULTS: A sampling frame was constructed by searching the databases of publicly registered charities for England, Scotland and Wales, registers of breed rescues, and by internet searches of animal welfare websites. Overall, 2,352 contacts for 1,380 organisations were identified. All were sent a postal questionnaire asking for data on the number of dogs and cats housed, their origins and eventual outcomes, and details of husbandry between January 1st and December 31st 2010. For those which were registered charities (595), financial records were also obtained. A response rate of 38.8 % was obtained. Overall, in 2010, 89,571 dogs and 156,826 cats entered the care of the participating organisations. Approximately half of these animals were relinquished by their owners. Other origins included being found as strays or confiscated for welfare purposes. Seventy-five per cent of dogs and 77.1 % of cats were rehomed. The next most common outcome was euthanasia, accounting for 10.4 % of dogs and 13.2 % cats. For dogs and cats, 44.3 % and 62 % of participants respectively reported having a waiting list, which frequently exceeded the actual capacity of the facility. Over 19,000 people were involved in the care of these animals, on a paid or voluntary basis. Financial records were available for 519/595 (87.2 %) of the registered charities, and their total expenditure in 2010 was GBP340 million. CONCLUSIONS: This study showed that a large number of animals become un-owned each year, which could have considerable implications for their welfare. Despite the resources expended, demand still exceeds capacity for many organisations, and a substantial number of both cats and dogs are euthanased, suggesting that further understanding of how and why these animals become un-owned is essential in order to target interventions. 相似文献
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The European newts have been the subject of several phylogenetic analyses, using a variety of character sets, from biochemical to ethological. As a result, the European newts have probably been subjected to more diverse and intense phylogenetic analysis than any other vertebrate genus in the world. The various techniques used have yielded conflicting results, but recent analyses that combine different kinds of data promise a resolution of the problem. 相似文献
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