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Fifty-five moose (Alces alces) collected from 1963 to 1965 in the Chapleau Crown Game Preserve of northern Ontario were examined for ectoparasites. Dermacentor albipictus was the only parasite recovered. D. albipictus was absent from 15 moose examined during June, July and August; first observed on 1 or 2 moose examined in September; and present on all 38 moose collected from October to May. Ticks were not evenly distributed on the body. Infestations varied from 32 to 13,490 ticks/moose for 14 individuals. Levels of infestation observed did not have an obvious adverse effect on the health of the moose.  相似文献   

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Two adult moose (Alces alces) from Colorado (USA) were naturally infected with Elaeophora schneideri. Both animals had patent infections indicating that moose may serve as definitive hosts. Gross and histological lesions were characterized by fibromuscular intimal proliferation within the carotid arteries and rete mirabile cerebri. This is the first report of Elaeophora schneideri in moose from Colorado.  相似文献   

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Parelaphostrongylosis has a rapid onset and is lethal in neonatal moose (Alces alces) when large numbers of third-stage Parelaphostrongylus tenuis larvae (L3) are given experimentally. Little is known, however, about the severity and prognosis of infections acquired naturally by accidentally ingesting terrestrial gastropods which are rarely infected and have few larvae. To investigate the relationship between infecting dose, age of moose, and severity of disease, five calves were given low doses of three to 10 L3 when five (n = 2) or 9.5 mo old (n = 3). Each of two animals initially given low doses were later challenged with a dose of 15 L3. As positive controls, two calves were given doses of 15 and 30 L3, considered to be high. All five calves given low doses showed abnormal locomotory signs at 20-28 days postinoculation (DPI) that progressively became more pronounced with hind quarter weakness and front lameness. However, after 77-130 DPI, signs diminished markedly in two of these animals and disappeared in another two. Challenge infections of 15 L3 given 199 days after initial infections had no noticeable effects although an immature worm, probably resulting from the challenge, was found in the spinal cord of one animal killed 51 days later. Two positive control animals given the high doses of 15 and 30 L3 showed moderate to severe, non-resolving, locomotory signs and had to be euthanized. Results demonstrate that single, low doses of three to 10 P. tenuis L3 cause moderate disease in moose calves but over time, some worms die and animals can recover. A degree of protection may develop against future infection.  相似文献   

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Five captive moose calves each infested with 42,000 larval Dermacentor albipictus, six calves each infested with 19,000-21,000, and five control moose were observed for changes in hair-loss, body condition and number, stages, and distribution of the tick. Winter hair-loss was observed only in moose infested with ticks and was correlated positively with the total number of adult ticks. Hair-loss associated with ticks was minimal from October to January, but rapidly increased from February to April when up to 44% of hair had been removed. The pattern of hair-loss was similar in all moose with the neck, shoulders, withers, and perianal areas losing the most hair. Moose with extensive premature hair-loss had less pericardial and abdominal visceral fat than moose with little or no hair-loss.  相似文献   

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We used a simple life table approach to examine the age-specific patterns of harvest mortality in eight Norwegian moose populations during the last 15 years and tried to determine if the observed patterns were caused by hunter selectivity. The general opinion among local managers is that hunters prefer to shoot female moose not in company with calves to keep a high number of reproductive females in the population (and because of the emotional stress involved in leaving the calf/calves without a mother), and relatively large males because of the higher return with respect to meat and trophy. In support of the former view, we found the harvest mortality of adult females to be higher among pre-prime (1–3 years old) than prime-aged age classes (4–7 years old). This is probably because prime-aged females are more fecund and, therefore, more likely to be in company with one or two calves during the hunting season. As the season progressed, however, the selection pressure on barren females decreased, probably due to more productive females becoming ‘legal’ prey as their calf/calves were harvested. In males, we did not find any evidence of strong age-specific hunter selectivity, despite strong age-dependent variation in body mass and antler size. We suggest that this was due to the current strongly female-biased sex ratio in most Norwegian moose populations, which leaves the hunters with few opportunities to be selective within a relatively short and intensive hunting season. The management implications of these findings and to what extent the results are likely to affect the future evolution of life histories in Norwegian moose populations are discussed.Electronic Supplementary Material Supplementary material is available for this article at and accessible for authorised users.  相似文献   

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Twenty-one moose were captured on Isle Royale between 28 May and 2 June 1984 at licks on the western end of the island. The animals were darted, at ranges of 10 to 35 m, with 3-cc dart syringes containing 3 or 4 mg of carfentanil and 100 or 175 mg of xylazine. Three animals were drugged with carfentanil alone. Immobilization time ranged from 2.5 to 6 min. There was no excitement phase evident in 18 of the animals and they rarely moved more than 30 m after darting. Reversal was begun at 30 to 90 min after darting using naloxone and diprenorphine given intramuscularly (i.m.) and intravenously (i.v.). Recovery time varied from 10 min to 3 hr with the longer times occurring at the higher doses of immobilizing drugs. Two animals died within 30 hr, one as the result of aspiration of rumen contents and the other was unable to get on its feet and was euthanized. Analysis of blood samples from the 18 moose immobilized with the drug combination yielded hemoglobin values of 13.1 +/- 0.3 g/dl, hematocrit: 37.6 +/- 0.7%, red blood cells: 5.46 +/- 0.1 million/microliter, leucocytes: 6.1 +/- 0.4 thousand/microliter, and serum urea nitrogen: 29.3 +/- 1.6 mg/dl. Our experience indicated that quiet, undisturbed moose can be immobilized with 3 mg carfentanil and 100 mg or less of xylazine.  相似文献   

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We attempt to identify geographical subdivisions within the range of moose according to antler size for a more correct trophy evaluation in the СIC system (The International Council for Game and Wildlife Conservation). Traditionally, this division coincides with subspecific division of trophy animal species. That is why we partially touch upon the problem of the geography of moose subspecies in Eurasia. Catalogs of hunters’ trophies that were available to us served as the research material (1,047 trophies in total). We were choosing the same measurements for moose antlers evaluated by different methods. They are overall spread, circumference of beam, width of palm, and number of tines. We applied multivariate statistic methods to the findings, enlarging the geographical division groups step by step. As a result, we suggest four geographical groups: European, Siberian, the north of the Far East, and the south of the Far East. In principle, this division corresponds to the subspecies: European (Alces alces alces L., 1758), east Siberian (A. a. pfizenmayeri Zukowsky, 1910), Chukotka or Kolyma (A. a. buturlini Chernyavski et. Zhelesnov, 1982), and Ussuri (А. а. cameloides Milne-Edwards, 1867). We consider it incorrect to draw the line between the European and Siberian groups along the river Yenisei. It is more correct to move it to the Urals.  相似文献   

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Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces alces) adults, yearlings, and calves in Norway sampled from 1992-2000. Additionally, we demonstrated that both induction time and chase time were correlated with initial rectal temperature, although they were not significantly correlated with cortisol, aspartate aminotransferase, glucose, or creatine kinase. Overall, the reference ranges given here are similar to those given for American moose, with a few differences that can be attributed to environment, testing methodology, or subspecies or species status. This is the first report, to our knowledge, of reference ranges for moose in Norway.  相似文献   

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Geographical variation in male carcass weight, and sexual dimorphism in size was studied in 19 populations of Norwegian moose ( Alces alces (L.)).
Significant age-specific variation in male carcass weight was found for all the populations studied up to the age of 4 1/2 years, but in some populations maximum weight was not reached until at least 5 1/2 years. Increase in the mean weight of females after the age of 2 1/2 years was not significant. Only a weak relationship existed between mean yearling and adult bull weights in a population. However, within both the southern (< 62°N) and northern (> 62°N) parts of the country, yearling carcass weight was a good predictor of adult bull weight in a region.
Adult bull weight in a region was best predicted from the increment in mean carcass weight observed between 1 1/2 and 3 1/2 years of age. Within a region, variation in age-specific carcass weight between cohorts of bulls from different years was also well predicted from annual variation in growth increment.
Those patterns reveal a sexual difference in strategy of body growth. The adult weight of females is probably strongly determined by the weight gained by the time of onset of reproduction. The males have available a longer period for growth in body weight. They are therefore able to compensate for low weights early in life by increased gain of weight in later years, that provide good conditions for growth.
Geographical variation in the degree of sexual dimorphism in size correlated only poorly with adult male size. We suggest that the sexual size-dimorphism is a result of reproductive constraints of the female, i.e. in populations living in poor conditions and having small body size, the onset of reproduction prevents further gain in body weight.  相似文献   

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We tested the concept that moose (Alces alces) begin to show signs of thermal stress at ambient air temperatures as low as 14 °C. We determined the response of Alaskan female moose to environmental conditions from May through September by measuring core body temperature, heart rate, respiration rate, rate of heat loss from exhaled air, skin temperature, and fecal and salivary glucocorticoids. Seasonal and daily patterns in moose body temperature did not passively follow the same patterns as environmental variables. We used large changes in body temperature (≥1.25 °C in 24hr) to indicate days of physiological tolerance to thermal stressors. Thermal tolerance correlated with high ambient air temperatures from the prior day and with seasonal peaks in solar radiation (June), ambient air temperature and vapor pressure (July). At midday (12:00hr), moose exhibited daily minima of body temperature, heart rate and skin temperature (difference between the ear artery and pinna) that coincided with daily maxima in respiration rate and the rate of heat lost through respiration. Salivary cortisol measured in moose during the morning was positively related to the change in air temperature during the hour prior to sample collection, while fecal glucocorticoid levels increased with increasing solar radiation during the prior day. Our results suggest that free-ranging moose do not have a static threshold of ambient air temperature at which they become heat stressed during the warm season. In early summer, body temperature of moose is influenced by the interaction of ambient temperature during the prior day with the seasonal peak of solar radiation. In late summer, moose body temperature is influenced by the interaction between ambient temperature and vapor pressure. Thermal tolerance of moose depends on the intensity and duration of daily weather parameters and the ability of the animal to use physiological and behavioral responses to dissipate heat loads.  相似文献   

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Phylogeography can help to determine LGM refugia and postglacial migration routes. However, the locations of LGM refugial areas in eastern Europe are not clear. Moose (Alces alces) is presently a common species in central and north-eastern Europe, but there are no studies showing its phylogenetic pattern and genetic diversity across its whole continuous range. Moose never became extinct in the eastern part of its range, and the eastern mtDNA lineage has the largest effective population size. The present study shows the phylogeographic pattern and genetic diversity of European moose and compares the results of mtDNA analyses with the archaeological record of the species to identify its LGM refugia and postglacial migration routes. I combined the mtDNA control region sequences obtained in all studies of moose in Europe and western Asia. The genetic data were then compared with the archaeological records of the species dated to the LGM. I found that the European moose lineage inhabits Europe and western Asia. It is composed of two clades: the eastern and the central-western, consisting of a total of six discrete haplogroups. The most complex, the eastern clade, has the largest range. Some of the haplogroups have narrow or scattered distributions and two are common in almost the whole range. Genetic diversity hotspots were detected in contact zones of different mtDNA haplogroups rather than in the LGM refugial areas of moose. Archaeological records dated to the LGM were found in several localities in central, southern and eastern Europe as well as in western Asia. The range of the moose during the LGM was much larger than previously thought. The eastern clade survived the LGM in western Siberia, the Ural Mountains and Russian plain. LGM refugia of moose were also located in the Caucasus, Carpathians, Balkans and northern Italy.  相似文献   

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Investigation of the distribution of larval Echinococcus granulosus in a moose population from southwestern Quebec revealed a distinct and stable pattern of infection with a prevalence of 44% (n = 580). Positive correlations between moose age and the intensity, mean cyst weight and biomass of the hydatid cysts suggested a process of continued parasite acquisition and cyst growth. The distribution of cyst sizes within individual moose provided circumstantial evidence of interaction between cysts, perhaps mediated through the host's immunological response.  相似文献   

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Winter recreation can displace ungulates to poor habitats, which may raise their energy expenditure and lower individual survivorship, causing population declines. Winter recreation could be benign, however, if animals habituate. Moreover, recreation creates trails. Traveling on them could reduce energy expenditure, thereby increasing ungulate survivorship and generating population benefits. Balancing recreation use with wildlife stewardship requires identifying when these effects occur. This task would be simpler if guidelines existed to inform assessments. We developed and tested such guidelines using two approaches. First, we synthesized literature describing the effects of winter recreation—motorized and nonmotorized—on northern ungulates. This synthesis enabled formulating six guidelines, while exposing two requiring further attention (ungulate habituation and displacement). Second, we tested these two guidelines and evaluated the others by quantifying the behavioral responses of moose to snowmobiles, in two areas of south-central Alaska, differing by snowmobile predictability. For each location, we modeled moose preferences during the snowmobile period using different combinations of eight variables—static (elevation and slope), biotic (habitat and cover), and anthropogenic (distance to roads, railroads, snowmobile trails, and trail density). We identified the model with the most support and used it to estimate parameter coefficients for pre- and post-recreation periods. Changes in coefficients between periods indicated snowmobile effects on moose. Overall, we produced and evaluated six guidelines describing when winter recreation is potentially detrimental to ungulates as follows: (1) when unpredictable, (2) spanning large areas, (3) long in duration, (4) large spatial footprint, (5) nonmotorized, and (6) when animals are displaced to poor quality habitats.  相似文献   

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Confirming Parelaphostrongylus tenuis infection in moose (Alces alces) and other susceptible hosts is difficult. An enzyme-linked immunosorbent assay (ELISA) was developed using the excretory-secretory (ES) products of third-stage P. tenuis larvae (ES-ELISA) and the test applied to serum samples obtained from seven moose calves (5-9.5 mo old) given infective larvae (L3) in doses approximating those likely to be received in nature (3-30 L3). Anti-P. tenuis immunoglobulin G antibodies were detected in all seven inoculated moose during the course of infection until the termination of experiment 61-243 days post-inoculation (DPI). Five animals tested between 16-25 DPI had significant antibody levels, while a sixth animal did not test positive until 46 DPI. The seventh animal was not tested until 199 DPI. Antibody levels remained elevated in all five animals that harbored adult worms at the termination of the experiment. Whereas, antibody levels showed a gradual decline in the two remaining animals, presumably because of death of worms, and antibodies were undetected in one animal at the time of necropsy. The other animal displayed an anamnestic increase in antibody level following a challenge inoculation of infective larvae. Terminal and peak optical density (OD) values detected by ES-ELISA strongly correlated with inoculation dose (r = 0.98, P = 0.02 and r = 0.95, P = 0.04, respectively) among animals harboring adult worms (n = 4) but not significantly with the number of worms recovered postmortem (peak OD, r = 0.82, P = 0.18; terminal OD, r = 0.93, P = 0.07). Unlike the ES products, use of somatic antigens of the adult worm in ELISA did not provide satisfactory results. Antibodies to P. tenuis were detectable by ES-ELISA in two of 21 free-ranging moose from an enzootic area but not from any of 23 animals from a non-enzootic area. The ES-ELISA appears to be a useful test for assessing exposure of moose to P. tenuis.  相似文献   

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Knowledge on reproductive success is vital for successful management of large ungulates and is often measured by means of observing surviving offspring. In harvested ungulates, postmortem investigations of reproductive organs are used to estimate reproductive potential by obtaining ovulation rates and fetus numbers. However, there are differences in numbers of offspring observed, fetal/embryo counts, and ovulation rates. We hypothesize that the discrepancy between estimated reproductive potential and reproductive outcome in large ungulates is not only due to ova loss but also due to embryonic mortality. We investigated reproductive status in early pregnancy by sampling hunter-harvested moose (Alces alces) in southern Sweden from 2007 to 2011. In all, 213 reproductive organs were examined postmortem, and in confirmed pregnant moose (n?=?53), 25 % (19 of 76) embryos were nonviable and 6 % of ova was unfertilized. The discrepancy between the ovulation rate of all pregnant moose (1.49) and the number of expected offspring per pregnant female, when embryonic mortality and unfertilized oocytes were accounted for (1.08), was 27.5 %. An association between inflammation of the inner mucous membrane (endometritis) of the moose's uterus and embryonic mortality was observed. This is the first comprehensive report of embryonic mortality and endometritis in moose. The observed discrepancy between ovulation rates and early embryonic development/survival shows that ovulation rates are indicative but not accurate estimates of moose reproductive rate. The use of ovulation rates as a sole estimator of future offspring rates may lead to an overharvest of a managed moose population.  相似文献   

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