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J. R. López-Olvera D. Vidal J. Vicente M. Pérez L. Luján C. Gortázar 《European Journal of Wildlife Research》2009,55(1):75-79
Serum samples from 101 mouflons (Ovis aries musimon) collected from July 2002 to January 2006 were tested for antibodies against Anaplasma spp., Brucella spp., bovine viral diarrhea virus, Chlamydophila abortus, Coxiella burnetii, Mycobacterium avium ssp. paratuberculosis, and Maedi-Visna virus. Mouflon came either from extensive farms or high ungulate density fenced hunting estates. Antibodies
were detected against Anaplasma spp. (22.2%), C. burnetii (4.0%), M. avium ssp. paratuberculosis (1.0%) and C. abortus (1.0%). According to our results, mouflons could participate as a wild reservoir in the epidemiology of Anaplasma spp. infection and maybe Q fever, but they do not seem to contribute in the epidemiology of the rest of the studied infectious
diseases in south-central Spain. 相似文献
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Linking temporal variations of genetic diversity, including allelic richness and heterozygosity, and spatio-temporal fluctuations in population abundance has emerged as an important tool for understanding demographic and evolutionary processes in natural populations. This so-called genetic monitoring was conducted across 12 consecutive years (1996-2007) at three sites for the feral cat, introduced onto the Kerguelen archipelago fifty years ago. Temporal changes in allelic richness and heterozygosity at 18 microsatellite DNA loci were compared with temporal changes in the adult population abundance index, obtained by typical demographic monitoring. No association was found at the island spatial scale, but we observed an association between genetic diversity and adult population indices from year to year within each study site. More particularly, the magnitude of successive increases or decreases in the adult population abundance index appeared to be the major factor linking the trajectories of genetic diversity and adult population abundance indices. Natal dispersal and/or local recruitment, both facilitated by high juvenile survival when the adult population size is small, is proposed as the major demographic processes contributing to such an observed pattern. Finally, we suggested avoiding the use of the harmonic mean as an estimator of long-term population size to study the relationships between demographic fluctuations and heterozygosity in populations characterized by strong multiannual density fluctuations. 相似文献
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Jennie Whinam Nicholas Fitzgerald Micah Visoiu Geof Copson 《Ecological Management & Restoration》2014,15(1):41-51
Australia's sub‐Antarctic Macquarie Island is presently undergoing one of the most ambitious vertebrate pest eradication programmes ever undertaken. The anticipated success of this programme will release the island's tundra‐like vegetation from well over a century of grazing and disturbance from House Mouse (Mus musculus), Ship Rat (Rattus rattus) and most significantly European Rabbit (Oryctolagus cuniculus). This study describes results from 30 years of vegetation quadrat monitoring (prior to the most recent and comprehensive pest eradication programme) when lower level pest animal control programmes were underway. Plant species were assigned to one of five distinct functional plant groups: Indigenous short‐lived perennials, Introduced short‐lived perennials, Indigenous perennials rarely grazed by rabbits, Indigenous perennials occasionally grazed by rabbits and Indigenous long‐lived perennials heavily grazed by rabbits, with one species, Agrostis magellanica, analysed as a sixth monospecific group. Results from monthly rabbit counts were used to compare changes in abundance of these six groups under different rabbit populations. It was found that there were three distinct phases of rabbit activity during the study period, indicated by (i) an initial very high count year in 1980–1981, followed by (ii) 20 years of low counts ending in 2001–2002 after which (iii) counts rose to medium/high until the commencement of the eradication programme in 2010–2011. Vegetation composition and progression were distinct for these three rabbit count phases. The first four of the plant functional groups decreased under lower count periods and increased in cover under higher rabbit count periods. Agrostis magellanica appears to respond primarily to interspecies competition and is disadvantaged under extended periods of low rabbit numbers. Indigenous long‐lived perennials heavily grazed by rabbits, which includes the large tussocks and megaherbs, is inversely related to rabbit numbers. During the study period, there has also been an overall decline in plant species richness with average species count per quadrat falling by between 0.6 and 2.7 taxa. This study attempts to address the observed vegetation change from this long‐term monitoring, to discuss other potential contributing factors and to use the results to predict likely future vegetation changes after eradication of vertebrate pests. 相似文献
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R Gentile V Sciscioli G De Metrio M Lenti G Passantino 《Bollettino della Società italiana di biologia sperimentale》1983,59(12):1761-1766
The authors have extended a preliminary study about the innervation of urinary bladder, confirming the previous results pointing out the presence of metasympathetic ganglions in the wall of urinary bladder. Therefore nine urinary bladders of Ovis aries of different age and both sexes have been studied by Ruffini, Bodian and Bielschowsky's staining methods. It's possible summarize the data on the innervation of urinary bladder in the following way: in the tunica adventitia there are motor and sensitive bundles of myelinated nervous fiber. The formers, after many divisions, penetrate into the tunica muscularis contacting bundles of smooth muscle fibers, while the latters after several divisions after giving rise to thinner bundles, produce Pacini-like and Ruffini-like sense corpuscles and free nervous terminations. Furthermore, some metasympathetic ganglions of different size have been detected throughout the running of the bundles. In the tunica submucosa a diffuse and peculiar non myelinated network is observed, arising from the vegetative nervous fibers. 相似文献
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An intestinal capillariid nematode, Aonchotheca musimon n. sp., is described from Ovis musimon imported into the Kerguelen archipelago (Terres Australes et Antarctiques Françaises). The comparison of this new material with other Aonchotheca spp. is based on the usual characters, i.e. spicule, caudal bursa, number of papillae, stichosome, bacillary bands, shape of the cirrus, and on the length of the ejaculatory duct which appears to be of some phylogenetic value. A. musimon, of which the spicule is 208–230 m long, is close to A. bilobata, another parasite of bovids, which is redescribed here. It is distinct from this species because the posterior region of the female worm is cylindrical instead of conical, the lateral alae of the male worm are longer, quadrangular and vesicular instead of triangular and smooth, the caudal bursa has a folded dorso-lateral edge, there is a recurrent ventral fold of the cirrus, the slender distal part of the spicule is longer, the oesophagus is shorter in both sexes and the slightly larger eggs have a thicker shell. These two species from bovids and A. murissylvatici from murid rodents, of which the main characters are similar, represent a small group with a very elongate ejaculatory duct (1.9–2.5 mm). This is in contrast to a larger group of species with a short ejaculatory duct (350–600 m), which are parasites of Chiroptera (A. brosseti, A. chabaudi, A. landauae, A. gabonensis), Insectivora (A. erinacei), mustelid Carnivora (A. putorii, A. mustelorum) and glirid rodents (A. myoxinitelae, A. legerae). A. bovis and A. dessetae, respectively parasites of bovids and lagomorphs, present an ejaculatory duct of intermediary length and do not belong to these groups.Several species are tranferred to the genus Aonchotheca: A. kashmirensis (Raina & Kaul, 1982) n. comb., A. legerae (Justine, Ferté & Bain, 1987) n. comb., A. forresteri (Kinsella & Pence, 1987) n. comb., A. chabaudi (Justine, 1989) n. comb., A. landauae (Justine, 1989) n. comb., A. brosseti (Justine, 1989) n. comb., A. gabonensis (Justine, 1989) n. comb. and A. dessetae (Justine, 1990) n. comb. 相似文献
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The seasonal variations in grouping patterns of the forest-dwelling Cyprus mouflon were examined over the annual cycle. Most of the trends observed in the size and composition of groupings agree with previous work on open-country living sheep. The main difference between Cyprus mouflon, which live in forest, and wild sheep living in open country, was in the overall group size, which is smaller in Cyprus mouflon. In fact, in their overall group size, Cyprus mouflon seem to follow the pattern of other forest-dwelling ungulates. 相似文献
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B Masala L Manca E Cocco S Ledda S Naitana 《Comparative biochemistry and physiology. A, Comparative physiology》1991,100(3):675-680
1. Hemoglobin (Hb) switching in the perinatal life of wild mouflon (Ovis musimon) was characterized by the replacement of Hb F by 60% levels of Hb C, and subsequently of Hb C by Hb B. 2. The recently discovered Hb M variant was not replaced by Hb C; thus, Hb BM heterozygote newborns synthesized 30% Hb C at the expense of Hb B. 3. Hybrid B mouflon x B sheep synthesized only 5% Hb C at birth but were able to produce 30% Hb C in adult life following induced anemia. 4. Adult BB and BM mouflons, after the same extent of induced anemia, synthesized HB C levels similar to those produced at birth. The results indicate a mouflon beta-globin gene cluster arrangement similar to those of sheep and goat, the beta C gene having an intermediate expression. Results also suggest a selective disadvantage in hybrid animals. 相似文献
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The plant communities in the Iles Kerguelen (South Indian Ocean) have been extensively modified by human activities, particularly through the deliberate release of rabbits, and the intentional or accidental introduction of several plant species. During the 1990 and 2000s, a decrease in precipitation resulted in a drastic reduction of some native plant species and in the increase in alien taxa. To monitor at a wide spatial scale the rapid changes of vegetation cover induced by summer droughts, we developed a method combining field data and satellite image analysis. A long-term field monitoring of plant communities was initiated on five small islands in 1992, and annually continued for over 15?years on a total of 161 line transects. Among these islands, the rabbit??which was the only introduced herbivore??was eradicated on three, remained on one control island, and had never been present on a second control island. We computed a linear model to link remote sensored vegetation indexes to plant cover deduced from line transects in numerous habitat types. After testing 14 vegetation indexes, we used a model based on the normalized difference vegetation index to precisely map the vegetation cover at several dates. A map of differences and spatial statistics indicated that vegetation cover, as a whole, decreased over the 15-year period. This study provides a reliable tool for long-term monitoring of the dynamics of plant cover in relation to climate change on the Iles Kerguelen. 相似文献
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Internally consistent G-, Q- and R-banded karyotypes and idiograms for sheep chromosomes at the 422-band level of resolution are presented. These were derived by sequential Q- to G-staining, and sequential Q- to R-staining of prometaphase spreads prepared from sheep with normal and Robertsonian chromosomes. The fused chromosomes served as stable morphological markers. To minimise confusion due to chromosomal nomenclature, we have listed chromosome-specific (reference) molecular markers that have been mapped byin situ hybridization to sheep chromosomes. The use of molecular markers in conjunction with the sequential Q- to G- and sequential Q- to R-banded karyotypes and iodiograms provided here will elimiate ambiguities in identifying and numbering sheep chromosomes and will facilitate their comparison with cattle chromosomes. Edited by: J.B. Rattner 相似文献
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A classical paradigm in population genetics is that homozygosity or inbreeding affects individual fitness through increased disease susceptibility and mortality, and diminished breeding success. Using data from an insular population of mouflon (Ovis aries) founded by a single pair of individuals, we compare embryo number of ewes with different levels of inbreeding. Contrary to expectations, ewes with the highest levels of homozygosity showed the largest number of embryos. Using two different statistical approaches, we showed that this relationship is probably caused by heterozygosity at specific genes. The genetics of embryo number coupled with cyclic dynamics could play a central role in promoting genetic variation in this population. 相似文献
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The unambiguous identification of ovine chromsomes has become essential for the mapping of the sheep genome, which predominantly consists of telocentric chromosomes of gradually decreasing size. Nucleolus organizer regions (NORs) and Robertsonian fusions have been used here as the cytological and morphological markers, respectively, to define the banding pattern of eight paris of sheep telocentric chromosomes that have an ambiguous identification status. Five Robertsonian chromosomes involving most of the ambiguous chromosomes as well as normal prometaphase chromosomes were stained sequentially and separately by QFQ, GTG, and Ag-NOR methodologies. The prometaphase banding patterns of the ambiguous chromosomes 4, 6, 8, 9, 21, 24, 25 and 26 are represented schematically. For providing an accurate image of the banding pattern, a system of shading has been employed to show the relative intensity of bands in a given chromosome. The results presented here will facilitate the regional mapping of the sheep genome, extend the information on cytogenetic homology with other bovids, and substantially accelerate the comparative mapping studies in Bovidae. 相似文献