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A simple technique for artificial insemination in hares was performed and used routinely in mass breeding of hares in captivity. Sperm was collected directly from the epididymides of males. Ovulation was induced by intravenous injection of human chorionic gonadotropin. Female hares were successfully inseminated throughout the year. Pregnancy occurred in 70% of inseminated females; the range in litter size was 1--3 offspring with a mean of 1.4. It was concluded that artificial insemination greatly simplified the breeding of hares in captivity.  相似文献   

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A substantial portion of today’s biodiversity is attributed to the climatic oscillations of the Pleistocene Ice Ages. Gradual but dramatic climate changes were accompanied by expansion, contraction, and isolation of populations, promoting the accumulation of genome differences and adaptations in refugial populations and resulting in allopatric differentiation in a variety of taxa. In the present study, partial mitochondrial DNA sequences of the widely distributed European brown hare (Lepus europaeus) were analyzed to test whether the species’ present genetic structure is the result of postglacial re-colonization of Europe from Asia Minor (clade A) and the Balkans (clade B) only, as suggested previously, or if additional refugia are likely. Analyses indicated the presence of an additional refugium (Italy, clade I). The genealogic network of Italian hares displayed the tree-like structure expected from refugial populations, whereas central European brown hare haplotypes revealed a clear star-phylogeny indicative of past-bottleneck population growth. This population size expansion, which was confirmed by mismatch analysis, was estimated to have occurred ∼50–55 thousand years ago (kya). The divergence of clade A* from the remaining matrilines is estimated at 239 kya, whereas the divergence of the ancestors of clades B* and I from A* occurred about 128 kya. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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We investigated the parasite communities of introduced Iberian hares (Lepus granatensis) and native European hares (Lepus europaeus) in southern France, where Iberian hares were introduced locally 20 yr ago as a game animal. Parasite communities of sympatric populations of the two hare species and of allopatric populations of European hares were compared. Iberian hares in France harbored a depauperate community of parasites relative to the population in its native habitat in Spain. European hares in areas of sympatry also were infected by Nematodiroides zembrae, which normally infects Iberian hares on their native range.  相似文献   

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European hare Lepus europaeus populations have undergone recent declines but the species has successfully naturalised in many countries outside its native range. It was introduced to Ireland during the mid-late nineteenth century for field sport and is now well established in Northern Ireland. The native Irish hare Lepus timidus hibernicus is an endemic subspecies of mountain hare L. timidus and has attracted major conservation concern following a long-term population decline during the twentieth century and is one of the highest priority species for conservation action in Ireland. Little is known about the European hare in Ireland or whether it poses a significant threat to the native mountain hare subspecies by compromising its ecological security or genetic integrity. We review the invasion ecology of the European hare and examine evidence for interspecific competition with the mountain hare for habitat space and food resources, interspecific hybridisation, disease and parasite transmission and possible impacts of climate change. We also examine the impact that introduced hares can have on native non-lagomorph species. We conclude that the European hare is an emerging and significant threat to the conservation status of the native Irish hare. Invasive mammal species have been successfully eradicated from Ireland before and immediate action is often the only opportunity for cost-effective eradication. An urgent call is issued for further research whilst the need for a European hare invasive Species Action Plan (iSAP) and Eradication strategy are discussed.  相似文献   

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Since October 1986 an unusually high mortality has been observed both in wild European brown hares (Lepus europaeus) and in hare farms in Italy. Pathological alterations, including severe hepatosis, nephrosis, congestion and hemorrhages of tracheal mucosa and lungs, and splenic vascular congestion, were observed in 179 of 381 hares necropsied from 1986 to 1988. Jaundice also was seen in 30% of these hares. Histologically, the liver damage was characterized by coagulative necrosis, mainly located around the portal areas, or by degenerative changes. Hyperemia, focal hemorrhages and periportal mononuclear cell infiltration were also present. The epithelium of renal tubules showed the presence of various degrees of vacuolar degeneration and necrosis, and eosinophilic granular hyaline casts or homogenous proteinaceous material were found within the lumen of tubules. Only the adult hares were affected. In wild hare populations night counts revealed a reduction of the number of observed wild hares during the winter period which ranged from 27 to 40%, whereas in hare farms the mortality ranged from 30 to 90%. Bacteriological, parasitological, and toxicological investigations were unable to confirm the primary cause of these deaths. Negative stain electron microscopy and immunoelectronmicroscopy conducted since October 1988 on liver and spleen homogenates from hares with acute hepatosis revealed the presence of viral particles with morphological aspects resembling those of calicivirus, antigenically related to the etiological agent of viral haemorrhagic disease of rabbits.  相似文献   

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The aim of the study was to show whether it is possible to induce ovulation in the hare by GnRH analogue administration and to carry out an effective artificial insemination (AI). The research was carried out during the breeding and non-breeding season. During the breeding season, plasma progesterone concentrations increased on the 4th day after intramuscular injection of GnRH analogue (buserelin), indicating induced ovulation and corpus luteum development. Prostaglandin F(2)alpha (dinoprost) was an effective luteolytic agent on day 9. During the non-breeding season, the GnRH analogue injection does not cause an increase of progesterone. The 17beta-estradiol concentrations during the breeding and non-breeding season were similar. It was shown that after GnRH analogue administration and artificial insemination with semen diluted in Tris buffer extender 80% females delivered live young (39-43 days after artificial insemination), which proves the effectiveness of inducing ovulation in the hare by means of hormonal stimulation.  相似文献   

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Two medium-sized herbivores with high trophic overlap coexist on rocky outcrops in the Patagonian landscape: the southern vizcacha (Lagidium viscacia), which is a native rock specialist, and the European hare (Lepus europaeus), which is a non-native species. We determined the patterns of space use related to distance from outcrops and analyzed spatial overlap between the two species. There were significant differences between the two species in the use of space adjacent to outcrops. The southern vizcacha mainly uses short and medium distances from the outcrop (up to 40 m), whereas the hare’s greatest activity was recorded at distances greater than 50 m. However, there is a partial overlap at medium distances (30–40 m) among both herbivores. Although, in general terms, there is no significant spatial overlap between hares and southern vizcachas, their biological characteristics and the high dietary overlap between the species allow us to predict that, if resources become scarce, the hare could extend its area of activity, as what happens elsewhere, and exploit food resources near outcrops, increasing the vulnerability of vizcacha colonies.  相似文献   

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The southern vizcacha (Lagidium viscacia) is a rock specialist that inhabits small colonies in isolated rocky outcrops of northwestern Patagonia. This study analyzes its diet selection in relation to food availability, establishes the degree of dietary specialization, and discusses the potential competition with exotic herbivores. Diet composition and food availability were determined in summer and winter in eight rocky outcrops by microhistological analysis of fecal pellets, and food availability was estimated by the Braun Blanquet cover abundance scale. Vegetation cover differences were detected by using a random analysis of variance (ANOVA) factorial block design, and dietary preferences were determined by the confidence interval of Bonferroni. The southern vizcacha showed a specialized feeding behavior despite the consumption of a wide variety of items. Their diet was concentrated on a few types of food, mainly grasses, and the trophic niche was narrow and without seasonal variations. In winter, when food was scarce and of lower quality than summer, diet was dominated by Stipa speciosa, suggesting a selection according to the selective quality hypothesis. Our results (narrow trophic niche, restricted activity near rocky outcrops, and a diet with high proportions of low-quality grasses) showed that the vizcacha is an obligatory dietary specialist, and these characteristics made it highly vulnerable to changes in food availability. In this scenario, overgrazing caused by alien species with similar diets, as the European hare and livestock, could negatively affect their colonies.  相似文献   

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The study aimed at defining reference values for electrocardiographic (ECG) and echocardiographic parameters as well as macroscopic dimensions of the heart and microscopic dimensions of cardiomyocytes in the European brown hare. The studies were conducted on 30 adult, clinically healthy hares of either sex caught in Poland. ECG and echocardiography were performed supravitally on anaesthetized hares. After euthanasia, gross and microscopic myocardial and cardiomyocyte dimensions were determined. Heart rate amounted to 140 ± 37.5 beats/min, the leading rhythm involved the sinus rhythm. P wave time was 26 ± 5 ms, PQ time was 80 ms, QRS time was 29 ± 3.5 ms, and ST was 97.5 ± 7 ms. Echocardiography determined a left ventricular wall end-diastolic diameter of 8.6 ± 2.0 mm and an intraventricular septum end-diastolic diameter of 5.75 ± 1.0 mm. The thickness of the interventricular septum corresponded to that of the free wall of the left ventricle, a finding consistent with physiological hypertrophy. Preliminary reference values were established for echocardiography. The findings were similar to those obtained at necropsy. The ECG and echocardiographic studies represent the first supravital examination of cardiac function in the hare. The obtained results illustrate adaptation of hare's myocardium to its mode of life. The cardiac findings resemble the athlete's heart syndrome described in humans. The findings may prove useful in further studies on the physiology of the cardio-vascular system in the hare.  相似文献   

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Both the Cytb gene of mtDNA and Y chromosome markers were studied in a relatively large sample of brown hares (L. europaeus) from Europe and Anatolia (Turkey and Israel), together with other seven Lepus species, in order to enable comparative analysis of possible sex-specific gene flow. Furthermore, Y chromosome markers were compared with data from biparentally inherited markers in an attempt to understand whether or not their pattern of distribution was congruent with that of allozymes or whether they rather matched mtDNA phylogenies, with which they share uniparental inheritance. Consistent with the general observation, levels of interspecific genetic variability were very low for the Y chromosome markers compared with mtDNA. Moreover, lack of interspecific variation for the Y-DNA studied within Lepus genus rendered these markers improper for any further phylogenetic analysis. With the highest nucleotide diversity in Anatolia compared with Europe, both marker systems confirmed an unbroken species history in Anatolia, corroborated the hypothesis of continuous gene flow from Anatolia's neighbouring regions, and supported the idea of a quick postglacial colonization followed by expansion of the species in large parts of Europe. Phylogenetic analysis under mtDNA revealed the existence of four different haplogroups with a well defined distribution across Europe and Anatolia. Both genetic systems supported the deep separation of Anatolian and European lineages of L. europaeus. Nevertheless, Anatolian Y-DNA lineages extended across a longer geographic distance in south-eastern Europe than Anatolian mtDNA haplotypes, probably as a result of higher female philopatry that makes mtDNA introgression more difficult in brown hares.  相似文献   

14.
European hares selectively feed on plants with high fat and hence energy content. We hypothesized that these dietary requirements limit the ability of hares to adjust daily food intake during periods of high energy requirements, namely lactation. Our measurements in captive lactating females show that does kept on a low-fat diet increased food intake compared to does on a high-fat diet but assimilated significantly lower amounts of energy. Further, does fed a low-fat diet showed a prolonged rise of food intake during lactation, reduced milk energy content and lower milk mass production at large litter sizes. We hypothesize that impaired milk production under suboptimal fat supply is due to the inability of females to increase the capacity of nutrient-processing organs rapidly enough to meet the high energy demands of precocial juveniles with high metabolic costs. Thus, in hares, the production of precocial young may be viewed as a constraint, caused by their inability to dig thermally buffered burrows, rather than as an adaptive reproductive strategy. We suggest that the interaction of lactation energetics, dietary requirements, and reduced plant diversity in modern agricultural landscapes has facilitated the decline of hare populations across Europe over the last decades.  相似文献   

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We describe a new method for the sex determination of tissue originating from Oryctolagus cuniculus (European rabbit), Lepus europaeus (European brown hare) and Lepus timidus (mountain hare) based on PCR-RFLP analysis of point mutations that differentiate the ZFX and ZFY gene sequences. Among several applications, this PCR-RFLP method could be used to investigate gender ratio and evaluate the population dynamics of these species using samples collected when sex cannot be identified.  相似文献   

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An animal’s home range use is influenced by the landscape type. European hare (Lepus europaeus) home ranging behaviour has been studied only in agricultural areas with medium to large fields. In agricultural areas with small fields, European hares’ locomotor behaviour is expected to be more localised. We tracked nine European hares by means of global positioning system (GPS) and very high-frequency (VHF) collars during summer in an agricultural area with small fields in Lower Austria. In particular, we analysed the hares’ space use at a fine temporal scale, such as when they were active and resting within single 24-h periods. Furthermore, we compared data (day–day distances and day–night distances travelled) calculated from GPS and VHF telemetry. Home ranges were smaller, and the distances between areas used for activity and inactivity were shorter, in this agricultural area with small fields than has ever been measured in other agricultural areas with larger fields. Both active and inactive European hares expressed a preference for areas near field edges. Our findings suggest that with GPS, it is possible to distinguish between the movement path and the relative location of distinctly used areas within an animal’s home range, whereas with VHF these two parameters may be difficult to separate. In conclusion, our results show that in areas where resources are easily accessible, such as in agricultural areas with small fields, the European hare is able to reduce its home range size to almost half of the minimum size that has been recorded so far in other habitats. As small home ranges involve less energy expenditure for movement, our results suggest that animals living in agro-ecosystems may benefit from small fields.  相似文献   

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The major histocompatibility complex is one of the best studied systems in vertebrates providing evidence for the long-term action of selection. Here, we examined the intra- and inter-population genetic diversity of the MHC class II DRB locus in European brown hare (Lepus europaeus) and correlated the results with genetic variability already estimated from the MHC DQA locus and from maternally (mitochondrial DNA (mtDNA)) and biparentally (allozymes, microsatellites) inherited loci. L. europaeus showed remarkable genetic polymorphism in both DQA and DRB1 loci. The Anatolian populations exhibited the highest genetic polymorphism for both loci. Balancing selection has established increased variability in the European populations despite the founder effects after the last glaciation. Different evolutionary rates were traced for DRB1 and DQA loci, as evidenced by the higher number of common DRB1 than DQA alleles and the greater differences between DRB1 alleles with common origin in comparison with DQA alleles. The high number of rare alleles with low frequencies detected implies that frequency-dependent selection drives MHC evolution in the brown hare through the advantage of rare alleles. Both loci were under the influence of positive selection within the peptide-binding region. The functional polymorphism, recorded as amino acid substitutions within the binding pockets, fell also within distinct geographic patterns, yet it was much narrower than the genetic polymorphism. We hypothesize that certain structural and functional characteristics of the binding pockets set limitations to the actual shape of genetic polymorphism in MHC.  相似文献   

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