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1.
Three loci in the genome of the white-footed mouse, Peromyscus leucopus, were examined for the presence or absence of orthologous copies of the retrovirus-like element mys using polymerase chain reaction. We examined these loci in 28 mice collected throughout the P. leucopus species range. Mys insertions were present in only one of the individuals examined at the mys-1 and mys-7 loci. Conversely, the mys-6 element was found in several individuals, but the presence of this element was limited to northern latitudes. Because the
long terminal repeats (LTRs) of a given element are expected to be identical at the time of retrotransposition into the genome,
and to accumulate changes over evolutionary time, within-element LTR sequence comparisons can be used to estimate the relative
age of insertions. Within-element LTR differences are greater in mys-6 than in mys-1 or mys-7. The LTRs from orthologous mys-6 elements of six mice were sequenced. The alignment revealed 13 of the 22 differences between the right and left LTRs that
were shared by all orthologous mys-6 sites, suggesting that relative to its time of insertion into the genome, mys-6 has only recently spread across the northern part of the species range.
Received: 23 January 1996 / Accepted: 24 April 1996 相似文献
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EUGENE C. BOVEE 《The Journal of eukaryotic microbiology》1966,13(4):607-610
SYNOPSIS. A new species of coccidium is described: Eimeria urosauris n. sp., in the gall bladder of the lizard Urosaurus graciosus Hollowell, from the Mojave Desert in California. The oocyst of E. urosauris is smooth, bilaminar, nearly cylindrical, with long borders only slightly convex, ends rounded and very nearly hemispherical. It is usually 32 × 20 μ, and its length/width ratio is 1.6. It contains 4 ellipsoid sporocysts, each 10.5 × 9 μ, for which 1/w is 1.17. Each sporocyst contains 2 tapered bent sporozoites with rounded ends, 11 μ long, 4 μ in diameter at the larger end, and 1.5 μ in diameter at the smaller end. Each sporocyst also contains a central granular sporocyst residuum 3.5 μ in diameter. The oocyst lacks a micropyle and oocyst residuum, and there is no Stieda body on the sporocyst. Sporulation time is 6–10 hr. Endogenous development, with reinfection by liberated sporozoites, occurs in the epithelial lining of the gall bladder. E. urosauris is compared to other morphologically similar lacertilian eimerias with which it might be confused. 相似文献
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SYNOPSIS. Eimeria bandipurensis n. sp., is described from the gut of an Indian palm squirrel, Funumbulus palmarum , obtained from a village, Bandipur, in West Bengal. Spherical and egg-shaped oocysts were encountered, the former averaging 17 μ in diameter and the latter 18 by 16 μ. Oocystic residuum was absent while the sporocystic residuum was represented by refractile globules. A Stieda body was present in the sporocyst. Sporozoites were banana-shaped with one end broader and the other pointed with a clear globule at each end. 相似文献
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Four new eimerian species are described from red-backed voles, Clethrionomys gapperi in Pennsylvania. Sporulated oocysts of Eimeria clethrionomyis sp. n. are ellipsoidal, 18.8 (16.5-21.5) x 14.9 (14.0-16.5) with elongate, ovoid sporocysts, 10.6 (9.5-12.0) x6.1 (5.5-7.0). The oocyst wall is smooth, with 2 layers, and thins, with terminal cap at one or both ends. Polar granules, dark Stieda body and sporocyst residuum are present. The oocyst residuum is absent. Sporulated oocysts of Eimeria gallatii sp. n. are ellipsoidal, 27.7 (21-32) x 19.3 (17-24) with ovoid sporocysts, 13.5 (12-15) x 8.8 (8-10). The oocyst wall is smooth, 2-layered, with a micropyle and thin wall at the end opposite the micropyle. Polar granules, Stieda body and sporocyst residuum are present. The oocyst residuum is atypical, of cobwebby material. Sporulated oocysts of Eimeria pileata sp. n. are subspherical to spherical, 25.2 (20.5-29.5) x 22.5 (19.5-25.5) with ellipsoidal sporocysts, 13.4(10.5-15.0) x 8.4 (7.5-9.5). The oocyst wall is rough, pitted, striated, 2-layered, with no micropyle. Polar granules, oocyst and sporocyst residuum, Stieda body and stiedal cap are present. Sporulated oocysts of Eimeria marconii sp. n. are ellipsoidal, 13.0 (10.5-15-0) x 10.6 (9.5-12.0) with elongate, ovoid sporocysts, 7.7 (7.0-8.5) x 4.2 (3.0-4.5). The oocyst wall is smooth, single-layered, with no micropyle. Polar granules, dark Stiedal body and sporocyst residuum are present. There is no oocyst residuum. 相似文献
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SYNOPSIS. Eimerians from 27 gray squirrels Sciurus carolinensis sampled in Waterloo County were studied. Two double-walled species, E. ontarioensis n. sp. which was piriform (36.8 × 23.5) and E. confusa Joseph which was subspherical (35.7 × 28.4), were described and compared with similar species from the genus Sciurus. Eimeria sp., ellipsoidal (24.9 × 14.4), from Ontario gray squirrels resembled E. ascotensis and E. neosciuri and was a new eimerian record from Ontario. The zoogeographic significance of E. ontarioensis n. sp. and E. sp. in North American gray squirrels is discussed. 相似文献
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SYNOPSIS Four new eimerian species are described from red-backed voles. Clethrionomys gapperi in Pennsylvania. Sporulated oocysts of Eimeria clethrionomyis sp. n. are ellipsoidal, 18.8 (16.5–21.5) × 14.9 (14.0–16.5) with elongate, ovoid sporocysts, 10.6 (9.5–12.0) × 6.1 (5.5–7.0). The oocyst wall is smooth, with 2 layers, and thins, with terminal cap at one or both ends. Polar granules, dark Stieda body and sporocyst residuum are present. The occyst residuum is absent. Sporulated oocysts of Eimeria gallatii sp. n. are ellipsoidal, 27.7 (21–32) × 19.3 (17–24) with ovoid sporocysts, 13.5 (12–15) × 8.8 (8–10). The oocyst wall is smooth, 2-layered, with a micropyle and thin wall at the end opposite the micropyle. Polar granules. Stieda body and sporocyst residuum are present. The oocyst residuum is atypical, of cobwebby material. Sporulated oocysts of Eimeria pileata sp. n. are subspherical to spherical, 25.2 (20.5–29.5) × 22.5(19.5–25.5) with ellipsoidal sporocysts, 13.4(10.5–15.0) × 8.4 (7.5–9.5). The oocyst wall is rough, pitted, striated, 2-layered, with no micropyle. Polar granules, oocyst and sporocyst residuum. Stieda body and stiedal cap are present. Sporulated oocysts of Eimeria marconii sp. n. are ellipsoidal, 13.0 (10.5–15.0) × 10.6 (9.5–12.0) with elongate, ovoid sporocysts, 7.7 (7.0–8.5) × 4.2 (3.0–4.5). The oocyst wall is smooth, single-layered, with no micropyle. Polar granules, dark Stieda body and sporocyst residuum are present. There is no oocyst residuum. 相似文献
9.
NORMAN D. LEVINE VIRGINIA IVENS FRANCIS J. KRUIDENIER 《The Journal of eukaryotic microbiology》1955,2(2):52-53
SUMMARY. Dorisiella arizonensis n. sp. (Sporozoa: Eimeriidae) is described from oocysts in the feces of a desert woodrat, Neotoma lepida , from Grand Canyon National Park, Arizona. The oocysts are spherical to subspherical, measure 20.8–21.8 × 20.8–22.9 μ, with a mean of 21.0 × 21.8 μ, and have a two-layered wall. They contain 1 to 3 refractile granules but no residual body. The two lemon-shaped sporocysts have a Stieda body, 8 sporozoites, and a few to many scattered, round, clear residual granules or bodies. 相似文献
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Emilie Roy-Dufresne Travis Logan Julie A. Simon Gail L. Chmura Virginie Millien 《PloS one》2013,8(11)
The white-footed mouse (Peromyscus leucopus) is an important reservoir host for Borrelia burgdorferi, the pathogen responsible for Lyme disease, and its distribution is expanding northward. We used an Ecological Niche Factor Analysis to identify the climatic factors associated with the distribution shift of the white-footed mouse over the last 30 years at the northern edge of its range, and modeled its current and potential future (2050) distributions using the platform BIOMOD. A mild and shorter winter is favouring the northern expansion of the white-footed mouse in Québec. With more favorable winter conditions projected by 2050, the distribution range of the white-footed mouse is expected to expand further northward by 3° latitude. We also show that today in southern Québec, the occurrence of B. burgdorferi is associated with high probability of presence of the white-footed mouse. Changes in the distribution of the white-footed mouse will likely alter the geographical range of B. burgdorferi and impact the public health in northern regions that have yet to be exposed to Lyme disease. 相似文献
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Calcium Availability Influences Litter Size and Sex Ratio in White-Footed Mice (Peromyscus leucopus)
The production of offspring typically requires investment of resources derived from both the environment and maternal somatic reserves. As such, the availability of either of these types of resources has the potential to limit the degree to which resources are allocated to reproduction. Theory and empirical studies have argued that mothers modify reproductive performance relative to exogenous resource availability and maternal condition by adjusting size, number or sex of offspring produced. These relationships have classically been defined relative to availability of energy sources; however, in vertebrates, calcium also plays a critical role in offspring production, as a considerable amount of calcium is required to support the development of offspring skeleton(s). We tested whether the availability of calcium influences reproductive output by providing female white-footed mice with a low-calcium or standard diet from reproductive maturity to senescence. We then compared maternal skeletal condition and reproductive output, based on offspring mass, offspring number and litter sex ratio, between dietary treatments. Mothers on the low-calcium diet exhibited diminished skeletal condition at senescence and produced smaller and strongly female-biased litters. We show that skeletal condition and calcium intake can influence sex ratio and reproductive output following general theoretical models of resource partitioning during reproduction. 相似文献
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SYNOPSIS. A new coccidium Sivatoshella lonchurae n. gen., n. sp. (Coccidia, Eimerüdae) is described from the gut of the passeriform birds Lonchura malabarica (Linn.) and L. punctulata (Linn.). Endogenous stages of the parasite conform to those of the family Eimerüdae. Oocysts are spherical, 36–38 μ (avg. 37.5 μ) in diameter. Wall 3.6 ä thick, 4-layered; outermost layer thin transparent and colorless; next, slightly broader and light green; 3rd, thinner and light yellow; innermost dark black. Oocyst residuum absent. Micropyle absent. Sporocysts 28–29 μ long and 18 μ wide. They are 2 broad pear-shaped bodies with Steida body and a prominent substeidal body at the narrow pole. Sporocyst residuum present as minute refractile globules embedded in a dark matrix. Sporozoites broad, comma-shaped, with one large vacuole at the broad pole and nucleus at the center of the body. Sixteen sporozoites in each sporocyst, arranged at the periphery of the residual mass. Sporulation time : 24–48 hours at 31 C. Habitat: duodenum and small intestine of Lonchura malabarica (Linn.) and L. punctulata (Linn.). Locality: Calcutta, W. Bengal, India. 相似文献
16.
IAN K. BARKER IAN BEVERIDGE BARRY L. MUNDAY 《The Journal of eukaryotic microbiology》1985,32(3):523-525
Oocysts of Octosporella hystrix n. sp., Eimeria tachyglossi n. sp., and E. echidnae n. sp. are described from the feces of the echidna Tachyglossus aculeatus (Monotremata: Tachyglossidae) from Australia. Eimeria tachyglossi has subspherical oocysts, 26.4 × 23.7 μm in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 13.2 × 9.7, slightly pointed at one end, each containing two sporozoites. Eimeria echidnae has subspherical oocysts, 19.4 × 17.8 in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 9.8 × 7.8, blunt at both ends, each containing two sporozoites. Octosporella hystrix has ovoid or subspherical oocysts 32.9 × 29.7 in size with a thick outer and thin inner oocyst wall; no micropyle; eight sporocysts spherical or slightly subspherical 11.3 × 11.2 each containing two sporozoites lying in embrace, with an extensive granular sporocyst residuum about the equator of the sporocyst. Endogenous stages considered to be of E. tachyglossi at least, were recognized in the lamina propria and epithelium on villi in the small intestine of three echidnas. 相似文献
17.
BETTY S. DAVIS 《The Journal of eukaryotic microbiology》1967,14(4):575-585
SYNOPSIS. Isospora peromysci n. sp., I. californica n. sp., and I. hastingsi n. sp. are described from 4 Peromyscus species in Monterey County, Central California. I. peromysci n. sp. was found in 35 of 1,346 Peromyscus , including P. californicus, P. truei , and P. maniculatus; I. californica n. sp. was found in 15 Peromyscus , including P. californicus, P. boylii, P. truei , and P. maniculatus ; and I. hastingsi n. sp. was found in one P. truei. Endogenous forms of I. peromysci n. sp. are described from P. maniculatus , and host distribution and incidence of all species are given. 相似文献
18.
F. G. POELMA 《The Journal of eukaryotic microbiology》1966,13(4):547-549
SYNOPSIS. Three new species of Eimeria are described from the intestinal contents of a galago Galago senegalensis E. Geoff. imported into the Amsterdam Zoo from Africa. The oocysts of E. lemuris n.sp. are 44-57 by 38-47 μ and contain 4 sporocysts measuring 17-20 by 10.5–14 μ. The oocysts of E. galago n.sp. are 20-25 by 19-23 μ and contain 4 sporocysts measuring 9-12 by 6-9 μ. The oocysts of E. otolicni n.sp. are 23-31 by 22-28 μ and contain 4 sporocysts measuring 10-15 by 8-12 μ. A few Isospora resembling I. arctopitheci Rodhain, 1933 were seen. 相似文献
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JOHN V. ERNST BILL CHOBOTAR DATUS M. HAMMOND 《The Journal of eukaryotic microbiology》1971,18(2):221-223
SYNOPSIS. Eimeria vermiformis sp. n. and E. papillata sp. n. are described from the mouse Mus musculus. The sporulated oocysts of E. vermiformis are 18–26 by 15–21 μ (mean 23.1 by 18.4 μ); its sporocysts are 11–14 by 6–10 μ (mean 12.8 by 7.9 p). The sporulated oocysts of E. papillata are 18–26 by 16–24 μ (mean 22.4 by 19.2 μ); its sporocysts are 10–13 by 6–9 μ (mean 11.2 by 8.0 μ). A substiedal body is present in E. papillata sporocysts. Patent infections were produced in white laboratory mice with both species. Fourteen species of Eimeria have now been described from the genus Mus. 相似文献