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Subspecific differences were found in total and esterified cholesterol of Malayan tree shrews. Thirty-twoT. glis sordida (Tioman Island) had mean levels of 73.4 mg% total cholesterol and 50.6 mg% esterified cholesterol. Mean levels of 57.3 mg% total cholesterol and 38.2 mg% cholesterol esters were found in 25T. g. ferruginea from the Malayan mainland. Other factors such as sex, pregnancy, and perhaps stress as related to diet and density of population, appeared to contribute to the variance of cholesterol level between insular and mainland forms.  相似文献   

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Graham M.  Lenton 《Ibis》1984,126(2):188-197
Moult in Malayan Barn Owls Tyto alba was studied in two pairs of wild collected captive birds and from feathers taken from nest sites throughout peninsular Malaysia.
Post-juvenile captive birds moulted nearly to completion prior to first breeding, beginning with P6 at a mean age of 301.5 days. This contrasted with the only other study of moult in captive Barn Ow-Is in Germany when moult began at an age of 400 days, and then continued for a protracted period of two years separated by a suspension of moult during the normal breeding season.
The complex sequence of moult in primaries and secondaries both in the Malayan and German birds was similar.
Moult among adult Malayan birds in the wild showed a broad and somebyhat irregular seasonal trend With lower incidence during peak breeding periods.  相似文献   

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Siamopaludina martensi and Filopaludina sumatrensis have typical viviparid reproductive systems with dimorphic spermatozoa and copulatory right tentacle in the male, and a large pallial brood-pouch in the female. Females outnumber males as in several other viviparids. Brood-pouches contained overall monthly averages of 0–14 developing young in S. martensi , 9–23 in F. sumatrensis , more than half of which were well-developed, later juveniles. Brood-pouch counts and ovary condition of both species varied in broad accordance with monthly rainfall, giving an irregularly seasonal pattern of annual change resembling those of several terrestrial Malayan snails. Juveniles emerge from the brood-pouch mostly at night. Alteration of aquarium conditions leads to temporarily accelerated release of young but does not permanently raise brood-pouch counts or rates of release.  相似文献   

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Summary Spore germination of various isolates of Fusarium (isolated from Malayan sources) was inhibited when placed on cellulose film in contact with soil moistened with distilled water. Intraspecific variations in sensitivity to mycostasis were recorded suggesting physiological differences between isolates of the same species. The addition of glucose frequently masked the mycostatic factor while autoclaving the soil completely removed it. The growth of fungal mycelium in contact with soil followed a similar pattern and when hyphae grew in contact with autoclaved soil sporulation was frequently observed.The similarities between the results outlined in this investigation and results from different countries is discussed and it is suggested that pathogenic fungi frequently have to overcome soil mycostasis before they can establish themselves in a new environment.  相似文献   

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Melanoides tuberculata in the Kuala Lumpur area of Malaysia were found to be entirely female, reproducing parthenogenetically. The reproductive system is extremely simple in structure and histology, lacking all the glandular developments common in most mesogastropods. Eggs pass into a cephalic brood-pouch where they develop to juveniles of 5–6 shell whorls before emergence. Numbers of developing young in the brood-pouches increased with shell height of the parents except for a decline in the few very largest snails. The highest brood-pouch count was 265, but average counts were much lower. 85 % of developing young in the brood-pouches were very early stages from eggs to embryos of one whorl only, perhaps implying that many eggs fail to develop successfully to young snails. Three localities studied yielded consistently different brood-pouch counts, implying variation in fecundity. Juveniles emerge from the brood-pouch most commonly between nightfall and midnight and normal emergence seems to require diurnal alternation of light and dark. In continuous darkness, brood-pouch counts increased markedly, perhaps as a result of greater activity and feeding during darkness. Several features of the reproductive biology suggest that Melanoides might become a useful experimental animal in freshwater studies.  相似文献   

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Lim Boo  Liat 《Journal of Zoology》1966,148(4):554-560
Laboratory and field experiments demonstrate that, contrary to previously published stomach analysis data, rats selectively consume land molluscs. Rattus jalorensis and R. argentiventer prefer molluscs as food, while R. exulans and R. r. diardi are less inclined to do so. Macrochlamys resplendens , a land snail, is most favoured, with the slug Micropar-mariort malayanus next in preference. The heavily-shelled Achatina fulica is only occasionally eaten and Quantula striata is ignored. Examination of gastro-intestinal contents of wild rats caught from various habitats in Malaya show that when present in large numbers molluscs form an important part of the natural food of rats, yet laboratory evidence demonstrates that as many as 60% of mollusc-eating rats may fail to show evidence of shells on examination within 12 hours of feeding–an indication that stomach analyses alone may be of limited value.
The Malayan insectivores Echinosorex gymnurus and Suncus murinus often feed on snails and slugs, though they appear not to be suitable hosts for infection with the rat lungworm Angiostrongylus cantonensis.  相似文献   

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Electrophoretic variation in nine red cell proteins was analysed in 256 specimens belonging to six species of Malayan Rattus (including one with two subspecies) of the subgenus Rattus. The average proportion of loci heterozygous per individual for the taxa analysed is 0.04. With the exception of Rattus rattus diardii, R. tiomanicus tiomanicus and R. t. jalorensis, individuals of the other species could be identified by specific electrophoretic phenotypes of one or more of the markers analysed. Relationships among the species studied were elucidated by the classical and phenetic approaches employing electrophoretic characters. The results obtained by the two approaches were similar in most respects and they corresponded better with results based on morphological characters than those based on cytological characters.  相似文献   

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Karyotypes of Malayan rats (Rodentia-Muridae,genus Rattus Fischer)   总被引:1,自引:1,他引:0  
Yong Hoi Sen 《Chromosoma》1969,27(3):245-267
The karyotypes of 18 species of Malayan rats, genus Rattus Fischer, are reported. Present studies reveal that the karyotype of rats is not species-specific. The variability in diploid number (2n) within the genus Rattus is reaffirmed. A range of 36 to 52 is reported, with 2n=42 having the highest frequency. The affinity of Malayan rats is discussed on the basis of chromosomal evidence.  相似文献   

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中国穿山甲和马来穿山甲头骨量度的测定及比较   总被引:3,自引:0,他引:3  
吴诗宝   《兽类学报》2004,24(3):211-214
全球共有7种穿山甲。本文报道的是中国穿山甲和马来穿山甲的头骨形态学资料,涉及头骨特征描述和一些形态学指标测定。被测定的指标主要有颅全长、基底长、腭长、眶间宽、后头宽、鼻骨长、鼻骨宽、脑颅高、听泡长和下颌长,并且在这两个物种之间进行了比较。结果表明,(1)这两个物种头骨形态十分相似,但马来穿山甲头骨细长,听泡长小于10mm(n=12),鼻骨狭长,前后部宽窄相似,两鼻骨外侧缘内凹或平行,鼻骨宽长之比值小于0 3000(0 2025~0 2811,n=12);而中国穿山甲头骨较粗短,听泡长大于11mm(n=46),鼻骨宽短,后部较前端宽,外侧缘外凸,鼻骨宽长之比值大于0 3000(0 3154~0 5325,n=33)。这些异同之处,可以作为区分这两个物种的依据。(2)中国穿山甲华南亚种与海南亚种头骨各变量之间的差异不显著(P>0 05),用颅全长是否大于83mm来区分这两个亚种不能成立,但海南亚种头骨上颌骨的颧突和鳞骨的颧突通常越过眶颞窝完全相接触,如果不是这样,则在它们之间有一个小的骨质棒状结构将它们连接起来。  相似文献   

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Within phylogenetic limits reproductive characteristics of a given species may vary between populations in response to ecological and social factors. For instance, in environments where high quality nutrition is readily available, the onset and speed of reproduction are often accelerated. Other influencing factors might be maternal experience or the sex of the infant. Here we present data on reproductive characteristics for the silvered leaf monkey (Trachypithecus cristatus), a medium‐sized Asian colobine housed at the Wildlife Conservation Society's Bronx Zoo as a one‐male group. To place the species into an appropriate phylogenetic context, we limited our comparison to other colobine species. Demographic data span 21.4 years (October 1985 to March 2007) and derive from 30 adult females (128.0 female years). Detailed behavioral data stem from a 2.2 years study (November 2002 to January 2005; 734 days, 4,225 hr). As in other Asian colobines, receptive periods were short (mean=4.3 days, n=68). This is expected for one‐male groups where receptivity likely indicates, rather than conceals, ovulation. Gestation length was estimated based on a change in the pattern of sexual behavior (mean=194.6 days, n=7). It fell within the range reported for the taxon. Births occurred year round, at an early age (mean=2.9 years, n=8), at short intervals (mean=14.9 months, n=59) in combination with a short lactation (mean 12.1 months, n=9) likely due to the nearly unlimited availability of nutrition in this zoo setting. Primiparous females tended to have a longer first interbirth interval but infant survival rates were similar to multipara possibly due to the absence of predators. Maternal investment was independent of the infant's sex and birth sex ratio was even. Our results emphasize that when interpreted with caution, zoo populations yield realistic reproductive characteristics that can help fill the gap in our knowledge about colobine life history. Am. J. Primatol. 71:852–859, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

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