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1.
Based on radio-tracking of raccoon dogs Nyctereutes procyonoides in Białowieża Primeval Forest (E Poland) in 1997–2002, we addressed the hypothesis that pattern of shelter use by this invasive
carnivore is an adaptation to both climatic conditions and predation. Raccoon dogs used various types of shelters but were
invariably concealed in dense vegetation or in the shelters created by trunks, branches, or roots of fallen trees (58% of
days). Burrows (mainly badger setts) and hollow trees (mainly fallen limes) were selected on 27% and 14% of days, respectively.
The pattern of shelter use varied throughout the year. In crucial periods (breeding period and winter), raccoon dogs used
shelter offering better protection: burrows and hollow trees (use of which increased with decreasing ambient temperature)
in winter, and hollow trees and dense vegetation during breeding and raising pups. The pattern of shelter use by raccoon dogs
was also strongly modified by forest structure. Raccoon dogs living in the pristine old-growth stands (with large amounts
of dead wood) utilized mainly natural shelters created by fallen trees (trunks, branches, and roots) and sedge tussocks (38%
and 37%, respectively). Individuals inhabiting the managed part of the Forest used mainly burrows (43%) and thicket (23%).
We recorded very strong monogamous relationships between pair mates, manifested by shared resting on 84% of days per year.
We conclude that hiding behavior and plasticity in shelter use is a response to high mortality due to predation and to unfavorable
climatic conditions. High adaptability to various environmental conditions may be one of the factors underlying successful
range expansion of raccoon dogs in Europe. 相似文献
2.
Daily ranges of 19 (6 males, 13 females) adult red deerCervus elaphus Linnaeus, 1758 were studied using 24-h tracking sessions in Białowieża Primeval Forest (BPF), Poland, from 2001 to 2004.
Overall, size of mean (± SE) daily ranges was larger for males (1.22 ± 0.10 km2) than females (1.00 ± 0.09 km2), although the difference was not significant. Similarly, mean daily ranges were 6–46% larger for males than females in each
season, although there were no statistical differences in mean daily ranges among seasons for each sex. Abiotic factors, especially
temperature, significantly affected daily ranges of females, but not males, suggesting sexual differences in response to weather
variables. On a daily basis, males used 3% of their annual home range, whereas females used 12% of their annual home range,
indicating females used their annual home ranges more intensely than males. Consecutive daily ranges overlapped little for
each sex. Daily ranges of red deer in BPF were considerably larger than previously reported in Europe, suggesting factors
unique to BPF also influenced size of daily ranges. 相似文献
3.
4.
Krzysztof Schmidt Włodzimierz Jędrzejewski Jörn Theuerkauf Rafał Kowalczyk Henryk Okarma Bogumiła Jędrzejewska 《Journal of Ethology》2008,26(1):69-78
Characteristics of the reproductive behaviour of wolves (Canis lupus) were studied by radio-tracking and snow-tracking of four packs in Białowieża Primeval Forest (BPF), Poland, in 1995–1999.
Signs of mating occurred between 12 January and 22 March. Parturition occurred between 19 April and 12 May, and the denning
period lasted for 49–64 days. During that time, wolves used 1–3 den sites, spending on average 27 days at each site. The dens
were never reused in consecutive years, but year after year the breeding sites were located in the same parts of the pack’s
territory. Ten days before parturition pregnant females reduced their normal mobility by half (from 23 to 13.5 km day−1, on average). During the ten days post-partum, they spent 85% of their time with pups and travelled 3.9 km day−1, only. On days 11–30 after parturition, females spent 74% of their time tending pups and increased their daily movement distance
to a mean of 13.3 km. The females resumed full mobility 50–70 days after parturition, which coincides with termination of
the weaning process. Anecdotal observations indicated that pups were tended by other pack members while the mother was absent.
Compared with the years 1947–1950, in 1995–1999 the breeding season of wolves in BPF occurred two weeks earlier. A possible
reason was the 1 to 1.5-degree increase in the mean annual temperature during the last 50 years. 相似文献
5.
Sabina Nowak Włodzimierz Jędrzejewski Krzysztof Schmidt Jörn Theuerkauf Robert W. Mysłajek Bogumiła Jędrzejewska 《Journal of Ethology》2007,25(3):231-237
We investigated spontaneous howling by radio-collared wolves Canis lupus inhabiting the Białowieża Primeval Forest (BPF), eastern Poland, and elicited howling behavior in wolves of the BPF and the
Western Beskidy Mountains, southern Poland. Over half (58%) of all spontaneous howls recorded throughout a year occurred in
the period from July to October, with a peak in August. The daily pattern of vocal activity by wolves was characterised by
a peak between 1800 and 0000 hours, which coincided with the first (dusk) peak of wolf mobility. Wolves howled from the core
areas of their territories and not from the peripheries. Howls served as communication between temporarily separated pack
mates (43% of cases), after re-union (18%) and before setting out for a hunt (22%). Very few spontaneous howls (2%) were targeted
at a neighbouring pack. Wolves responded to human-simulated howling in June–September, with a peak in August (reply rate:
39%). The duration of elicited howling increased significantly with group size: howls by single wolves or pairs lasted, on
average, 34–40 s, whereas those of five to seven wolves (including pups) had an average duration of 67–95 s, with a maximum
length of nearly 4 min. In the populations of Polish wolves studied here, spontaneous howling served primarily for intra-pack
communication. Nonetheless, the high reply rate to howling simulation showed that – if necessary – wolves readily advertised
their presence in a territory to strangers. 相似文献
6.
Włodzimierz Jędrzejewski Krzysztof Schmidt Bogumiła Jędrzejewska Jörn Theuerkauf Rafał Kowalczyk Karol Zub 《Acta theriologica》2004,49(2):275-280
In 1998, the pack of 7 wolvesCanis lupus Linnaeus, 1758, radio-tracked in Białowieża Primeval Forest, East Poland, split into 2 packs (2 and 5 wolves), when an 8-year-old
alpha female ceased breeding. The two sister-packs subdivided their original territory, but their ranges overlapped extensively
(49%) for one year after the split, except for May-June, when both new packs reared pups. We propose that food related factors
could have been the ultimate cause of splitting of a large pack. In European temperate forests, pack size of 5–6 wolves is
optimal for the consumption of the red deerCervus elaphus. 相似文献
7.
Claudia Melis Nuria Selva Ivonne Teurlings Christina Skarpe John D. C. Linnell Reidar Andersen 《Ecological Research》2007,22(5):807-813
Ungulate carcasses can have important effects on the surrounding soil and vegetation. The impact of six carcasses of European
bison (Bison bonasus) was investigated for the first time in a natural temperate forest (Białowieża, Poland) by measuring soil and plant nutrient
concentrations along a gradient extending from the centre of each carcass. Calcium concentration and pH were found to be higher
at the centre of the carcass, decreasing towards the periphery. This effect lasted up to 7 years after the death of the animal.
The concentration of most nutrients in the soil and plants varied irregularly, suggesting an effect of the carcass at its
centre but the absence of a clear pattern of variation along the gradient. Concentrations of NO3− in the soil differed only at the 1-year old carcass, suggesting a fast turnover of nitrate in temperate forests. Our results
show that the effects of large herbivore carcasses on soil and plant nutrient concentrations are not easily detectable in
a temperate forest as in more homogeneous habitats, such as tundra and prairie. This may be due to the high activity of scavengers
and nutrient recycling in the study area, but it may also be a consequence of a more complex and patchy interaction between
nutrient availability and other limiting factors in temperate forests. 相似文献
8.
Krzysztof Schmidt Włodzimierz Jędrzejewski Henryk Okarma Rafał Kowalczyk 《Ecological Research》2009,24(1):207-214
Various species of large predators are reported to influence each other through interference or exploitation competition that
may affect demography and survival of the subordinate species. We analyzed spatial relationships between grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx) in Białowieża Primeval Forest (BPF, eastern Poland) to determine how they partitioned the space. The wolves (n = 8) and lynx (n = 14) were radio-tracked in 1991–1999. Three wolves and seven lynx were radio-tracked simultaneously in 1994–1996. Territories
of wolf packs and home ranges of lynx overlapped considerably (76% of wolf territories and 50% of lynx home ranges, on average).
In three cases, their core areas were also overlapping. Wolf-lynx dyads with overlapping home ranges were simultaneously located
at distances from 0 to 28 km from each other. We found neither avoidance nor attraction between wolves and lynx occupying
the same areas. We concluded that in BPF, the two large predators coexist due to specialization on different preferred prey
and heterogeneous habitat. 相似文献
9.
Sarcoptic mange caused by Sarcoptes scabiei, is a highly contagious worldwide mite infection responsible for epizootic skin disease in populations of wild and domestic mammals. It causes skin disorders that may lead to severe generalized skin disease (mange). We investigated the spread and dynamics of sarcoptic mange in one of the best preserved carnivore communities in the Bia?owie?a Primeval Forest over the last 20 years. Sarcoptic mange was found in 6 of 10 investigated species. The highest percentage of infected individuals was recorded in red foxes (19 %), European badgers (9 %), grey wolves (7 %), raccoon dogs (6 %), and stone martens (5 %). Other species were not infected (least weasel, American mink, European polecat, pine marten) or infected sporadically (Eurasian lynx––1 case). Rate of infection was correlated with the sum of ecological and behavioral features, which may increase the spread of infection. Outbreaks of sarcoptic mange occurred simultaneously in several species of carnivores, which indicates the occurrence of between species transmission. We found that the source of investigated individuals (trapped, culled and found dead) may influence the results of the analysis. Our study shows that in carnivore communities such as in Bia?owie?a Forest, numerous species may serve as a reservoir of the pathogen and favor its persistence in the environment. This study indicates that sociality and use of den sites are important factors affecting sarcoptic mange spread and prevalence in wild populations of carnivores. 相似文献
10.
Bats were netted at two sites over the forest rivers Narewka and Hwoźna in Białowieża Primeval Forest (E Poland), during the summer of 1994 and 1995. A total of 452 bats of 11 species were captured. The number of bats netted each night was positively correlated with the minimum air temperature. The rate at which the three commonest species —Nyctalus noctula, Myotis daubentonii andNyctalus leisleri — were caught varied significantly through the night, with a major peak after sunset. ForN. noctula air temperature was apparently positively related to the size of the morning peak. 相似文献
11.
Background
The presence of β-lactamases in Y. enterocolitica has been reported to vary with serovars, biovars and geographical origin of the isolates. An understanding of the β-lactamases in other related species is important for an overall perception of antibiotic resistance in yersiniae. The objective of this work was to study the characteristics of β-lactamases and their genes in strains of Y. intermedia and Y. frederiksenii, isolated from clinical and non-clinical sources in India. 相似文献12.
Four stereoisomers of 2-norbornyl-N–n-butylcarbamates are characterized as the pseudo substrate inhibitors of cholesterol esterase. Cholesterol esterase shows
enantioselective inhibition for enantiomers of exo- and endo-2-norbornyl-N–n-butylcarbamates. For the inhibitions by (R)-(+)- and (S)-(−)-exo-2-norbornyl-N–n-butylcarbamates, the R-enantiomer is 6.8 times more potent than the S-enantiomer. For the inhibitions by (R)-(+)- and (S)-(−)-endo-2-norbornyl-N–n-butyl-carbamates, the S-enantiomer is 4.6 times more potent than the R-enantiomer. The enzyme-inhibitor complex models have been proposed to explain these different enantioselectivities. 相似文献
13.
The lipase Lip2 of the edible basidiomycete, Pleurotus sapidus, is an extracellular enzyme capable of hydrolysing xanthophyll esters with high efficiency. The gene encoding Lip2 was expressed
in Escherichia coli TOP10 using the gene III signal sequence to accumulate proteins in the periplasmatic space. The heterologous expression under
control of the araBAD promoter led to the high level production of recombinant protein, mainly as inclusion bodies, but partially
in a soluble and active form. A fusion with a C-terminal His tag was used for purification and immunochemical detection of
the target protein. This is the first example of a heterologous expression and periplasmatic accumulation of a catalytically
active lipase from a basidiomycete fungus. 相似文献
14.
Dana Bernátová 《Biologia》2008,63(2):175-176
The paper brings information on an isolated occurrence and morphological characters of Carex × involuta and C. juncella populations in the Vel’ká Fatra Mts. Their presence has been known neither from the territory of Slovakia nor from the whole
Western Carpathians till now. 相似文献
15.
Heike Helmholz Blair D. Johnston Christiane Ruhnau Andreas Prange 《Hydrobiologia》2010,645(1):223-234
Scyphozoan medusae are very successful foragers which occasionally occur in high abundances in boreal waters and may impact
many different groups in the marine ecosystem by means of a variety of toxins. A rainbow trout gill cell line, RTgill-W1,
was tested for its suitability as quantitative indicator of the cytotoxicity of Cyanea capillata and Aurelia aurita; the major scyphozoan species in the North and Baltic seas. Cultures of rainbow trout gill cells were exposed to whole venoms
extracted from fishing tentacles and oral arms at increasing protein concentrations. The venom caused detachment, clumping
and lysis of cells, as well as a drop in vitality, in a dose-dependent manner. Morphological changes in the cells were evident
within 1 h after venom addition. The damage to gill cells was quantified by measuring the metabolic activity of the cells
by means of the fluorescence of resorufin derived from the nonfluorescent substrate, resazurin. In general, a decrease in
the metabolic activity of the cells was detected at a venom (protein) concentration above 2.0 μg ml−1 (corresponding to 0.2 μg 104 cells−1), and a total loss of activity was observed above 40.0 μg ml−1 (corresponding to 4.0 μg 104 cells−1). C. capillata venoms had increased cytotoxic activity as compared to A. aurita venoms at the same concentration. Cnidocyst extracts from oral arms of A. aurita induced an 85% loss of gill cell viability at concentrations of 0.2 μg 104 cells−1, whereas crude venoms from fishing tentacles reduced cell viability by 18% at the same concentration. Gel electrophoresis
of the venoms indicated that these consist of a large number of proteins in a fairly wide size range, from 6 to 200 kDa, including
some that are the same size as those found in cubomedusae. It also appears that larger (i.e., older) medusae have more complex
venoms and, in some cases, more potent venoms than smaller animals. 相似文献
16.
Abdul Ghaffar Sher Afzal Khan Zahid Mukhtar Muhammad Ibrahim Rajoka Farooq Latif 《Molecular biology reports》2011,38(5):3227-3233
We studied heterologous expression of xylanase 11A gene of Chaetomium thermophilum in Pichia pastoris and characterized the thermostable nature of the purified gene product. For this purpose, the xylanase 11A gene of C. thermophilum was cloned in P. pastoris GS115 under the control of AOX1 promoter. The maximum extracellular activity of recombinant xylanase (xyn698: gene with intron) was 15.6 U ml−1 while that of recombinant without intron (xyn669) was 1.26 U ml−1 after 96 h growth. The gene product was purified apparently to homogeneity level. The optimum temperature of pure recombinant
xylanase activity was 70°C and the enzyme retained its 40.57% activity after incubation at 80°C for 10 min. It exhibited quite
lower demand of activation energy, enthalpy, Gibbs free energy, entropy, and xylan binding energy during substrate hydrolysis
than that required by that of the donor, thus indicating its thermostable nature. pH-dependent catalysis showed that it was
quite stable in a pH range of 5.5–8.5. This revealed that gene was successfully processed in P. pastoris and remained heat stable and may qualify for its potential use in paper and pulp and animal feed applications. 相似文献
17.
C. L. Govan D. W. Simpson A. W. Johnson K. R. Tobutt D. J. Sargent 《Molecular breeding : new strategies in plant improvement》2008,22(4):649-661
We have identified a reliable set of multiplexed microsatellite (SSR) markers for the genotyping of strawberry cultivars and
their octoploid progenitors. Over 100 SSRs were screened in two F. × ananassa genotypes and from these, 32 that showed promise for genotyping were selected for further analysis. These SSRs were used
to screen a set of 16 strawberry cultivars and a set of fingerprints were produced. Those SSRs that produced reliable, reproducible
and easy to interpret fingerprints, that could also distinguish readily between the 16 strawberry cultivars screened, and
which could be conveniently included in three multiplex reactions, were selected to form the genotyping set. The genotyping
set, consisting of 10 previously-reported SSRs was used to fingerprint a total of 56 cultivated strawberry, and four octoploid
Fragaria species accessions. The SSRs used could reliably distinguish between all 60 genotypes surveyed, including sibling cultivars
derived from the same parental lines. The primers could be combined for multiplex PCR and represent a useful and convenient
genotyping set for Fragaria that will permit fingerprinting data to be shared between laboratories. 相似文献
18.
Much attention has been focused on the study of lactoferrin at the protein or nucleotide level in mice, humans, and cattle, but little is known about it in goats. The goat LF gene from 5' UTR to exon 17 was amplified, and the variation of g.7605C→T in 10 Chinese indigenous goat breeds was analyzed. Among the three ruminant species (cattle, sheep, and goats), the intron-exon distribution pattern was similar, and all the exons had the same length, but the length of introns varied greatly due to insertions or deletions. The frequency of allele T at g.7605C→T (50.12%) was a little higher than that of allele C (49.88%), and the genotype distribution differed greatly between goat populations. The g.7605C→T site showed higher genetic diversity in goat populations. The genetic differentiation was 0.0783, and gene flow was 2.9433 among the 10 Chinese indigenous goat populations. 相似文献
19.
Ridha Dalhoumi Nicolas Morellet Patricia Aissa Stéphane Aulagnier 《European Journal of Wildlife Research》2018,64(3):36
We studied the seasonal activity pattern of the Kuhl’s pipistrelle Pipistrellus kuhlii in eight sites of the Bou Hedma National Park, central Tunisia, from June 2010 to June 2011, using both mistnetting and acoustic bat detection. Pipistrelles were captured all year-round only at water bodies. Captures peaked in late spring and early autumn. Pregnant females were observed from March to June, lactating females only in June, and flying juveniles from June to August. Echolocation calls and buzzes were recorded in all sites throughout the year. However, activity varied significantly among months and sites. Activity peaked in June and September after a noteworthy decline in August; the minimum was recorded in December and January. Bats mainly foraged at water bodies and around streetlamps. This result supports the previously reported major role of water bodies for bats in arid environments. Bats also foraged in the open acacia forest in summer, during the flowering period of Acacia Acacia tortilis raddiana. The steppe was the least used habitat. Social calls were mainly recorded in autumn around streetlamps, suggesting a swarming behaviour. Despite being a common bat species in the area, P. kuhlii should deserve conservation efforts that would benefit other bat species. 相似文献
20.