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Ivna Kocijan Estella Prukner-Radovčić Relja Beck Ana Galov Albert Marinculić Goran Sušić 《European Journal of Wildlife Research》2009,55(1):71-74
Faecal and vomit samples were collected from 12 griffon vultures (Gyps fulvus) in May 2002 and examined for bacteria, fungi and parasites. Bacteria present included Escherichia coli, Aeromonas salmonicidia, Proteus sp., Escherichia fergusonii, Providencia alcalifaciens, Micrococcus sp. and Streptococcus sp. Mycological examination revealed the presence of Candida sp., yeasts and in one case, Rhodotorula rubra. Strongyle eggs were found in several samples. In most faecal samples, ascarid eggs of Toxocara type were found. Tapeworm eggs of Moniezia type were present in one faecal sample. Both microbiologic and parasitic findings are most likely the result of the feeding
habits of griffon vultures. 相似文献
3.
Occupied and unoccupied sites of bearded vulture Gypaetus barbatus and Eurasian griffon Gyps fulvus were located in the Caucasus (mainly Georgia). Habitat variables related to nest-site characteristics, climate, terrain, human disturbance and food availability were used to construct predictive models of vulture breeding site selection by using a geographic information system (GIS), logistic regression and Bayesian statistical inference. The probability of bearded vulture occupancy of a cliff ledge that was safe from climatic adversity, human disturbance and predation was positively correlated with the following variables measured within a 20-km radius of the ledge: mean elevation, mean slope, the percentage of open areas, mean distance to roads, number of globally threatened wild goats Capra cylindricornis, C. caucasica and C. aegargus , and annual biomass of dead livestock. The probability of such a cliff ledge being occupied by Eurasian griffon was negatively correlated with annual rainfall at the ledge and positively correlated with the percentage of open areas and annual biomass of dead livestock within 20 km of the ledge. Provided that GIS coverage of the habitat variables is available, these models can be of help in various areas of the Caucasus and elsewhere to predict possible nest occurrence areas, and highlight sites where vultures may occur in the future if the population grows because of conservation or other activities. 相似文献
4.
Heinz-Josef Hirsch 《Archives of microbiology》1977,115(1):45-49
Bacteriocin-like activities were found in several Myxococcus fulvus strains. One strain, Mxf16, exerted strong inhibitory effects on several myxobacterial strains. Synthesis of its bacteriocinic activity could not be induced by mitomycin. Electrophoresis and molecular sieve chromatography revealed at least three different bacteriocinic substances of low molecular weight.List of Abbreviations cas lm
Casitone liquid medium
- TCA
trichloroacetic acid 相似文献
5.
A. Nègre L. Tarnaud J. F. Roblot J. C. Gantier J. Guillot 《International journal of primatology》2006,27(6):1495-1517
The study of self-medication among animals—zoopharmacognosy—is founded on observations that suggest that wild animals use plants with specific biological properties that may be beneficial to them. To verify whether self-vermifugation occurs among Eulemur fulvus in the wild, we studied their feeding behavior in both the dry and humid forests of Mayotte (Comoros Islands). We used the focal individual sampling method over an annual cycle. We conducted a complementary study during the 2-mo mating season, via the scan sampling method (at 10-min intervals). Among the 29 plant species brown lemurs consumed, we tested 16 in vitro as antiparasitic agents on 3 experimental parasite models (Rhabditis pseudoelongata, Trichomonas vaginalis, Entamoeba invadens). We obtained crude extracts to be tested after 2 successive chemical extractions (ethyl acetate and methanol), and 7 of them, belonging to 4 different plant species, showed an antiparasitic property: lemurs consumed Annona squamosa and Mimusops comorensis in large amounts, but ingested Ixora cremixora and Syzygium jambos sporadically. The 4 plants were active on the flagellate but only one of them (Ixora cremixora) also demonstrated antinematode properties. Humans use 2 of the plants as intestinal antiparasitic agents in traditional medicine and include numerous other plants in the diet. The relative lake of amoebas and flagellates in stools of Eulemur fulvus may be related to the consumption of plants with antiprotozoal properties. Nevertheless, in the absence of specific behavior that could be linked to a voluntary therapeutic action during our study, self-vermifugation in Eulemur fulvus remains elusive. 相似文献
6.
We experimentally tested the hypothesis that sexual dichromatism in the subspecies of Eulemur fulvus is the evolutionary result of female preference for brightly colored males. Ten female lemurs representing 6 different subspecies of Eulemur fulvus were subjects in the experiment; controls were 4 females of non-sexually dichromatic lemurid taxa. For each taxon we presented photographs of the face of a male of that taxon whose colors had been digitally altered to make him less and more colourful. Median viewing times of the pooled female Eulemur fulvus are significantly correlated with colorfulness. Viewing times in the control females are not correlated with color or brightness of the stimulus photographs. We concluded that the females of the Eulemur fulvus sspp. preferred to view photographs of more colorful males, which is consistent with the predictions of sexual selection theory. 相似文献
7.
The results of several experiments on reproductive behaviour of Tigriopus fulvus, indicate that females release a sex pheromone promoting sexual recognition and attraction in males. This compound has been verified to be not only species-specific, but also slightly modified in specimens belonging to different geographical populations. The compound possesses a mass of between 100 and 1000 daltons. A male can invest from one to 15 days in the precopulatory phase; delayed fertilization causes a strong reduction in the average number of offspring produced by parental specimens belonging to the oldest agegroups, but does not have any effect on the sex ratio. 相似文献
8.
Regina Karousou Despina Vokou Stella Kokkini 《Biochemical Systematics and Ecology》1998,26(8):889-897
The distribution of Salvia pomifera subsp. pomifera (Cretan sage) on the island of Crete is presented. The essential oils of six populations scattered on the island are studied. The essential oil content varies from 2.1–4.2%, whereas the main oil components were in all cases α- and/or β-thujone (27.4–72.3% and 7.1–40.8%, respectively). The comparison of our results to literature data, suggest that S. pomifera can be distinguished from S. fruticosa (Greek sage), on the basis of its essential oil composition. 相似文献
9.
Wolfgang Ludwig Karl Heinz Schleifer Hans Reichenbach Erko Stackebrandt 《Archives of microbiology》1983,135(1):58-62
Five representatives of the order Myxobacterales were characterized by oligonucleotide cataloguing of their 16S ribosomal RNA to determine their phylogenetic relationship to one another and to other gliding and non-gliding Gram-negative bacteria. Myxococcus fulvus, Stigmatella aurantiaca and Cystobacter fuscus are highly related, while Sorangium cellulosum and Nannocystis exedens are clearly separated from each other and from the former organisms. All myxobacteria are members of one line of descent, which is specifically related to the broad groups of non-sulphur and sulphur purple bacteria and their non-phototrophic relatives. Myxobacteria are distantly related to Cytophaga johnsonae, which stands completely isolated at present. 相似文献
10.
An 8-year study was conducted on the island of Crete in order to identify airborne ascospores and to determine their seasonal pattern. A Burkard 7-day, volumetric spore-trap was continuously operated in the city of Irakleion – located in the center of the island – from 1994 through 2001. Relatively „high” ascospore counts (20 – 48 spores/m 3) were obtained from mid-spring through summer, while the rest of the year exhibited lower activity (8–16 spores/m3). The predominant ascospores identified were those of Leptosphaeria and Chaetomium; their concentrations varied from 1 or 2 spores up to a few dozens of spores/m3. Other spores encountered sporadically were: Ascobolus, Endophragmiella, Didymella, Diatrypaceae, Leptosphaerulina, Massaria, Pleospora, Sporormiella, Xylaria. The mean daily concentration of all identified ascospores was 30/m3 for the entire study period, corresponding to 13.9% of the total fungal load. Ascospores have been recognized as important inhalant allergens and have been implicated as contributing to symptoms of both rhinitis and asthma. 相似文献
11.
The non «B» biotype ofBemisia tabaci (Gennadius) is recorded for the first time in Crete in 1992, in the north east and south east of the island.Trialeurodes vaporariorum (Westwood) is the predominant whitefly on plants in the north and west of the island. Three surveys of Crete were made in 1992 and 1993 for natural enemies ofB. tabaci andT. vaporariorum and resulted in the collection of 4 species ofEncarsia, (plus a number of species that are unidentifiable at this time), anEretmocerus sp. (unidentifiable at this time) and a fungal pathogen,Paecilomyces farinosus (Dickson Ex Fries) Brown &; Smith.Encarsia adrianae was identified fromT. vaporariorum; which constitutes its most westerly distribution point and a new host record respectively.B. tabaci andT. vaporariorum were found on horticultural crops, ornamentals and weeds. Populations of both whitefly species were severely depleted on field hosts throughout the island during the winter of 1992/93. Climatic constraints, competition withT. vaporariorum in otherwise suitable niches, effective natural enemies and an observed low level of polyphagy may explain the present limited distribution of the non «B» biotype ofB. tabaci in Crete. 相似文献
12.
Salsola komarovi lljin is a herbaceous annual native to the sand dunes and beaches of Japan, northern China, Sakhalln and Korea. Starch-gel
electrophoresis was conducted on leaves and stems collected from 300 plants in eight Korean populations. The mean number of
alleles per locus (A
p=1.51), mean expected heterozygosity (He
p=0.116), and total genetic diversity (H
T=0.279) were comparable with those for species with similar life history and ecological traits. A general conformance of genotype
frequencies to Hardy-Weinberg expectations (meanF
IS=−0.030) indicates thatS. komarovi is an outcrossing species. Slightly more than 20% of the genetic variation was found among populations (F
ST=0.204). In addition, significant differences in allele frequency were detected between populations at all 11 polymorphic
loci (P<0.001). Nei's genetic identities range from 0.885 to 0.985 with a mean of 0.942. However, indirect estimates of the number
of migrant per generation (0.97, calculated fromF
ST and 0.31, calculated from seven private alleles) indicate that the levels of gene flow is low among Korean populations. Although
the species maintains a moderate level of genetic variation within populations, the small, isolated natural populations of
the species have been severely destructed by human activities, particularly in summer season. If this is true, conservation
efforts should be focused on those populations that currently maintain the most genetic diversity (e.g., populations of Cheju
Island and coast of the southwestern Korean Peninsula). 相似文献
13.
Populations of Oriental White-backed Vulture (Gyps bengalensis) and Long-billed Vulture (Gyps indicus) declined dramatically by 95–100% on the Indian subcontinent in during the mid-1990s. The study reported here was conducted
in Pakistan to compare the population size, breeding success, patterns of mortality and sex ratios among dead vultures and
newly hatched nestlings of G. bengalensis and G. indicus at Toawala (TW) and Nagar Parkar (NP), respectively, during the breeding seasons 2005/2006 and 2006/2007. At TW, diclofenac
poisoning was most likely responsible for the high mortality and sex ratio imbalance among dead G. bengalensis, where vulture counts and breeding success declined quickly during the study period. However, at NP no significant difference
in population size, breeding success and annual mortality of G. indicus was recorded during the study period. A sex ratio imbalance was detected among nestlings of G. bengalensis, with 68% males and 32% females. In contrast, the sex ratio did not differ significantly in G. indicus. 相似文献
14.
P. Le Gouar F. Rigal M. C. Boisselier-Dubayle F. Sarrazin C. Arthur J. P. Choisy O. Hatzofe S. Henriquet P. Lécuyer C. Tessier G. Susic S. Samadi 《Conservation Genetics》2008,9(2):349-359
It is generally considered that limiting the loss of genetic diversity in reintroduced populations is essential to optimize
the chances of success of population restoration. Indeed, to counter founder effect in a reintroduced population we should
maximize the genetic variability within the founding group but also take into account networks of natural populations in the
choice of the reintroduction area. However, assessment of relevant reintroduction strategies requires long-term post-release
genetic monitoring. In this study, we analyzed genetic data from a network of native and reintroduced Griffon vulture (Gyps fulvus) populations successfully restored in Southern Europe. Using microsatellite markers, we characterized the level of genetic
diversity and degree of genetic structure within and among three native colonies, four captive founding groups and one long-term
monitored reintroduced population. We also used Bayesian assignment analysis to examine recent genetic connections between
the reintroduced population and the other populations. We aimed to assess the level of fragmentation among native populations,
the effectiveness of random choice of founders to retain genetic variability of the species, the loss of genetic diversity
in the reintroduced population and the effect of gene flow on this founder effect. Our results indicate that genetic diversity
was similar in all populations but we detected signs of recent isolation for one native population. The reintroduced population
showed a high immigration rate that limited loss of genetic diversity. Genetic investigations performed in native populations
and post-released genetic monitoring have direct implications for founder choice and release design. 相似文献
15.
Isolde Hagemann 《Plant Systematics and Evolution》1987,155(1-4):165-187
The morphology, altitudinal distribution and phytocoenology ofHypericum empetrifolium
Willd., var.oliganthum
Rech. fil. and var.tortuosum
Rech. fil. are reassessed and as a result, the taxa are treated at subspecific rank. Essential characters proved to be growth form, number of flowers, foliage and epidermal surface characters, shape of seeds and testa sculpturing.The different growth forms can be interpreted as adaptations to the local habitats.Hypericum empetrifolium
Willd. subsp.empetrifolium is a low subshrub of various vegetation types known as phrygana whereasHypericum empetrifolium
Willd. subsp.oliganthum (Rech. f.)Hagemann grows as a cushion-like dwarf shrub in chasmophyte associations rich in relic species.Hypericum empetrifolium
Willd. subsp.tortuosum (Rech. f.)Hagemann is confined in the high mountain regions and grows as a true dwarf espalier shrub with low spreading shoots.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday. 相似文献
16.
Data were obtained on the population structure and reproduction of Atlantoscia floridana, one of the most common species of terrestrial isopods in the restinga (coastal dune) forests of the state of Rio Grande do Sul, southern Brazil. During a 19-month period, a total of 7833 individuals were sampled: 2792 males, 3400 females and 1691 mancas. There was a significant difference between the size of both males and females collected in 2000 and 2001: the mean size was smaller in the second year when individuals in the larger size classes were lacking. Population density varied with season. The minimum population was 131 ind per m2 individuals, the maximum 1040 ind per m2 and the mean 450 per m2. While the overall sex ratio was clearly female biased, the operational sex ratio favored males, and showed no changes with season. Because both ovigerous and post-ovigerous females were present throughout the year, reproduction is considered continuous; however, reproduction peaked during autumn and spring. Ovigerous females were measured (CW = cephalothorax width) and the number of eggs was counted. Fecundity (F) varied from 5 to 23 eggs ( = 11.18 ± 4) per female, and was expressed by the regression F = –18.48 + 22.59 CW, with the female cephalothorax width varying from 1.04 to 1.68 mm. Marsupial mortality was only 0.9%. Egg production was 588 eggs per m2 in spring and 660 eggs per m2 in autumn. Recruitment occurred in all months, and eggs, embryos and marsupial mancas were also present year-round. A. floridana is the dominant species of terrestrial isopod in the study area. Its most remarkable characteristic is its high reproductive investment. 相似文献
17.
Summary This paper describes temporally varying determinants of the spatial distribution of adults in an insect population and the relationship between that distribution and the mating system. Male Oeneis chryxus butterflies were distributed nonrandomly throughout a sloping Colorado meadow divided horizontally by a dirt road into an upper and lower slope. Over an eight-year period of intensive study, the proportion of males located on the road, the upper slope, and the lower slope varied as a function of population size and sex ratio. In each year, more than half of the male population aggregated on sections of the road in a distinct and recurring pattern that was not correlated with the distribution of any food resource or thermal regime. Females were usually extremely scarce and not distributed in any pattern apparent from the few observations of them. Areas densely occupied by males were associated with visual landmarks. We hypothesize that the male distribution is determined by a pattern of movement of receptive females toward these landmarks. The road offers a thermally favorable environment with an unobstructed view in which to await the passage of scarce females. The mating system in this population has several lek-like features and supports the prediction that landmark mating is a favored strategy under conditions of female scarcity and wide dispersal of resources. 相似文献
18.
The climate of western Madagascar is characterized by a long (8–9 mo) dry season during which small rivers run dry, so that most animals are dependent on access to a few permanent water holes. We studied the effects of water scarcity at the end of the dry season on the ranging behavior of 4 groups of redfronted lemurs (Eulemur fulvus rufus) living at different distances from the Kirindy Riverbed in the Kirindy/CFPF forest northeast of Morondava. Using radio-collars, we located 2 resident groups with permanent home ranges near the river, and 2 non-resident groups and followed them for 60 days. We obtained a GPS reading every 30 min and later analyzed them with GIS ArcView to determine the size and location of each group's (core) home range. One group resided in direct proximity to the riverbed with several water holes and made regular short trips (mean 330 m) to drink. A second resident group had no direct access to water and made regular trips to the same water hole at a mean distance of 590 m from their home range. One non-resident group had a center of activity about 1300 m from the nearest water hole, to which they traveled on a non-daily basis. The other non-resident group established a temporary binuclear home range with one center of activity near the riverbed, about 2900 m away from the other center of activity. Thus, redfronted lemurs use different drinking and ranging tactics as a function of the distance of their core areas from the nearest water source. 相似文献
19.
Hemerocallis hakuunensis, a Korean endemic species, maintains considerably higher levels of allozyme variation within populations (meanHe=0.253) and substantially lower levels of allozyme divergence among populations (meanG ST=0.077) than average values reported for other insect-pollinated, outcrossing herbs. Indirect estimates of the number of migrants per generation (Nm=3.00, calculated fromG ST;Nm=3.57, calculated from the frequency of nine alleles unique to single populations) indicate that gene flow has been extensive inH. hakuunensis. This is somewhat surprising when we consider the fact that no specialized seed dispersal mechanism is known, flowers are visited by bees, and the present-day populations of the species are discontinous and isolated. Results of a spatial autocorrelation analysis based on mean allele frequencies of 19 populations reveal that only 13% (95/720 cases) of Moran'sI values for the ten interpopulational distance classes are significantly different from the expected values and no distinct trend with respect to the distance classes is detected. Although it is unclear how the populations are genetically homogenous, it is highly probable thatH. hakuunensis might have a history of relatively large, continuous populations that had more chance for gene movement among adjacent populations after the last Ice Age. In addition, occasional hybridization withH. thunbergii in areas of sympatry in the central and southwestern Korean Peninsula may be one factor contributing the present-day high allozyme variation observed inH. hakuunensis. 相似文献
20.
Píndaro Díaz-Jaimes Edson Sandoval-Castellanos Manuel Uribe-Alcocer 《Ichthyological Research》2007,54(4):380-387
Three snook species, Centropomus viridis, Centropomus medius, and Centropomus robalito, from the eastern central Pacific, representing three of the four proposed phyletic lineages in the genus, were analyzed
for genetic variability by means of allozyme and RAPD to evaluate the divergence between populations at different levels of
dispersal ability and to evaluate the importance of barriers to dispersal in the population subdivision and genetic diversity.
Levels of genetic diversity among species estimated by allozymes were similar and consistent with the observed levels of differentiation
in marine fish species. Mean heterozygosity ranged from 0.089 for C. viridis to 0.10 for C. robalito. Genetic diversity for the snook species studied was slightly higher than the mean estimation reported in allozymes for 106
marine fish (0.055) and for anadromous fish species (0.043 to 0.057). Multilocus allele frequency homogeneity tests and population-subdivision
estimates for both allozyme and RAPD markers revealed the existence of population structure in C. viridis and C. medius, in coincidence with geographic separation of samples, whereas no divergence was detected in C. robalito. This finding may be attributed to the greater population size of C. robalito, which originated by a recent population range expansion, and hence the potential for dispersal is mediated by larval drift.
Fluctuations in population size and population range expansion are used to explain discrepancies between levels of genetic
diversity and population structure in the studied species.
Supplementary material to this paper is available in electronic format at 相似文献