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1.
Using scanning electron microscopy (SEM), the external morphology of all developmental stages (egg, oncomiracidium, diporpa,
just fused juvenile and adult) of the parasite, Eudiplozoon nipponicum (Monogenea, Diplozoidae), from the gills of carp was studied. During the ontogeny, the tegument, tegumentary and sensory
structures are subsequently developed. The tegument of free swimming oncomiracidium occurs in two types — the ciliated and
non-ciliated with numerous uniciliated sensory structures. An attachment apparatus starts to form during the oncomiracidium
stage. Further developmental stages are adapted to the environment of the gills. Tegumentary folds become more apparent later
in development and assist to the parasite’s attachment. In connection with its reproductive strategy, the two morphological
structures of diporpa (ventral sucker and dorsal papilla) appear to play important role. On the gills, two individuals need
to meet and these structures mediate the fusion between two diporpae. The hindbody of adult parasite is highly modified for
attachment. The haptor, folds and lobular extensions are most developed. The forebody is flexible and able to interact with
host gill tissue via the mouth and associated mouth structures. The process of food intake of the parasite was discussed. 相似文献
2.
Mohammad Mustafizur Rahman Md Yeamin Hossain Qtae Jo Su-Kyoung Kim Jun Ohtomi Carl Meyer 《Ichthyological Research》2009,56(1):28-36
In order to investigate ontogenetic changes in diet and diet overlap between rohu (Labeo rohita) and common carp (Cyprinus carpio) in polyculture ponds, food preferences of different size classes of these fishes were quantified. Rohu diet consisted of
both phytoplankton and zooplankton, and there was a distinct ontogenetic shift in the relative importance of these food items.
Zooplankton was the dominant food for rohu up to 20.6 cm total length (TL) and then gradually decreased in importance as fish
grew. Phytoplankton was initially a minor component of rohu diet but gradually increased in importance and became the dominant
food for rohu at 24.2 cm TL. Phytoplankton biovolume in rohu guts was positively correlated with fish size (TL). Chesson’s
α indicated that rohu of all sizes preferentially selected Cladocera and avoided Cyanophyceae and Euglenophyceae. Young rohu
initially preferred Rotifera and Copepoda but gradually switched to Bacillariophyceae and Chlorophyceae. Common carp diet
consisted of phytoplankton, zooplankton, and benthic macroinvertebrates, but was dominated by benthic macroinvertebrates (63–92%
of total diet). As common carp grew, the proportion of zooplankton ingested decreased and the proportion of benthic macroinvertebrates
increased. Benthic macroinvertebrate biovolume in common carp guts was positively correlated with fish size. Common carp of
up to 15.4 cm TL preferentially selected zooplankton, but common carp larger than 18.9 cm TL avoided this food item. Common
carp of all sizes avoided phytoplankton. A low dietary overlap was found between rohu and common carp (Schoener overlap index:
0.08–0.35), probably due to ingestion of smaller quantities of zooplankton by the latter. Dietary overlap also decreased with
increasing rohu and common carp size because of divergent ontogenetic shifts in dietary preferences of the two species. 相似文献
3.
Mutation rate and pattern of microsatellites in common carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis> L.) 总被引:1,自引:0,他引:1
Microsatellites are popular molecular markers in genetic and evolutionary studies. Their mutational dynamics have been extensively
studied in humans and fruit flies, but few data were available in fish. By genotyping 55 individuals of a F1 pedigree, we
investigated the mutation rates and patterns of 49 microsatellites in one of the most important fresh water fish species,
the common carp (Cyprinus carpio L.). The overall mutation rate of the 49 loci was 5.56×10−4/locus/generation (95% confidence interval 1.52×10−4 and 1.63×10−3). The change of allele size was between +2 to −5 repeat units, assuming that the mutation allele arose from the parental
allele most similar in size to the mutant. 相似文献
4.
R. I. Ludanny G. G. Chrisanfova V. K. Prizenko A. K. Bogeruk S. K. Semyenova 《Russian Journal of Genetics》2010,46(5):572-577
Using five microsatellite loci, genotyping and genetic diversity estimates were obtained for nine samples representing seven
common carp breeds most widespread in Russia. For comparison, the samples of Amur wild common carp (Cyprinus carpio haematopterus) and a sample of European Hungarian carp were used. In the samples examined (n = 148) a total of 78 alleles were revealed. The highest mean allele number per locus (7.3) was identified in Amur wild common
carp, while the lowest number was found in Cherepets carps (4.0). In different breeds, the observed heterozygosities varied
from 0.819 (Altai carp) to 0.651 (Cherepets scaly carp). Three out of five microsatellite loci (MFW-24, MFW-28, and MFW-19) revealed a high level of population differentiation. In the dendrogram of genetic differences, all breeds clustered into
two groups. One of these groups was composed of the two strains of Ropsha carp, Stavropol carp, Amur wild common carp, and
the two samples of Cherepets carp. The second cluster included Altai carp (Priobskii and Chumysh populations), two Angelinskii
carp breeds (mirror and scaly), and Hungarian carp. The pairs of breeds/populations/strains, having common origin, were differentiated.
Specifically, these were two populations of Altai carp, two strains of Ropsha carp, as well as the breeds of Angelinskii and
Cherepets carps. The reasons for genetic differentiation of Russian common carp breeds, as well as the concordance of the
evolutionary histories of these breeds, some of which originated from the European breeds, while the others contain substantial
admixture of the Amur wild common carp, are discussed. 相似文献
5.
Two exotic fishes, common carp (Cyprinus carpio) and tilapia (Oreochromis niloticus), were introduced more than 20 years ago into Xochimilco for aquaculture, and now dominate the system in terms of biomass
and numbers. Over this same period, wild populations of the microendemic axolotl salamander (Ambystoma mexicanum) have been dramatically reduced, and it currently persists in isolated areas of this aquatic system, which is situated at
the edge of Mexico City. In this study, we examine potential trophic interactions and niche overlap among two exotic fishes:
carp and tilapia, and the native axolotl. Axolotl had more diverse diets and a higher trophic position compared to the exotics.
Stable isotope analysis revealed substantial trophic niche overlap among axolotl and the exotics. The two exotics occupied
a larger niche area than the axolotl, suggesting higher levels of omnivory and diet specialization. Current exotic fish removal
efforts will further our understanding of interactions between the axolotl and exotic species, and are expected to benefit
axolotl recovery efforts. 相似文献
6.
D. A. Balashov A. V. Recoubratsky L. N. Duma E. V. Ivanekha V. V. Duma 《Russian Journal of Developmental Biology》2017,48(5):347-353
Fertility of backcross triploid hybrids containing one genome of Prussian carp and two genomes of common carp is investigated. The females of hybrids of Prussian carp and common carp (Prussian × common carp) are prolific and produce diploid gametes. Since males of such hybrids are sterile, their reproduction is realized by means of induced gynogenesis. Triploid progeny is obtained by backcrossing female Prussian × common carp with carp males. Among triploids obtained from hybrids F1 and among hybrids of the first gynogenetic generation, there were no prolific specimens. However, in reproduction of diploid hybrids by means of gynogenesis during six generations, the female fertility in the backcross progeny is restored. From backcross triploid females (daughters of Prussian × common carp of the sixth gynogenetic generation), a viable triploid gynogenetic progeny and a tetraploid backcross (by carp) progeny are obtained. The obtained data may be considered as the experimental proof of the hypothesis of reticular speciation. 相似文献
7.
The present study is aimed at recording changes in taste preferences and behavior related to testing of artificial agar-agar
(2%) pellets with free amino acids (21 amino acids, L-isomers, 0.1–0.001 M) in the carp Cyprinus carpio at increasing duration of starvation (2, 12, 18, 24, 72, and 144 h). Two hours after the end of feeding until satiation,
the fish manifest a low foraging activity and, in most cases, they do not grasp the offered pellet. Later on, the feeding
motivation in fish increases rapidly and up to 24 h of starvation each of the offered pellets is grasped. In the first hours
of starvation the fish refuse from consumption of the grasped pellets even with highly attractive taste stimuli (extract of
chironomids, cysteine). Up to 24 h of starvation, the fish restore the differentiated attitude to taste properties of amino
acids. Of the latter, four amino acids increase, six decrease, and the other 11 do not render significant influence on consumption
of pellets. Up to 72 h of starvation, at the background of continuing increase in the absolute level of consumption of pellets
of all types, the taste preferences change but weakly. However, up to 144 h of starvation the number of deterrent amino acids
was reduced to one (phenylalanine). At increasing duration of starvation, the number of repeated grasping of pellets changes
weakly while duration of testing by fish of pellets of most types increases, especially abruptly in the first 24 h. It is
assumed that the decrease or complete loss in fish of the negative reaction to substances, initially having aversive taste
properties may be considered as the main mechanism providing expansion of the feeding spectrum and/or transfer of fish onto
consumption of new items, initially consumed just occasionally or fully avoided. 相似文献
8.
9.
10.
There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
11.
O. A. Torgunakova V. E. Chrisanfov V. K. Prizenko A. K. Bogeruk T. A. Egorova S. K. Semyenova 《Russian Journal of Genetics》2012,48(1):93-100
Polymorphism of the mitochondrial cyt b gene was examined in 35 individuals of common carp and wild common carp (Cyprinus carpio L.). The fish examined represented two natural populations from Khabarovsk krai (Ac and Am), Volga wild common carp, Don
wild common carp, and two common carp breeds, Ropsha (strains BB and MM) common carp and Hungarian common carp. The highest
level of nucleotide (π) and haplotype (h) diversity was detected in two strains of Ropsha common carp (MM, π = 0.67%, h = 0.7; and BB, π = 0.21%, h = 0.9) and in one population (Am) of Amur wild common carp (π = 0.26%; h = 0.6). The second population of Amur wild common carp (Ac) and Hungarian common carp were characterized by lower variation
estimates (π = 0.035%, h = 0.4; and π = 0.09%, h = 0.7, respectively). Genetic homogeneity was demonstrated for the populations of Volga and Don wild common carp (π = 0,
h = 0). In the sample of the cyt b sequences examined, three lineages were identified. Lineages I and II united all haplotypes of the Am Amur wild common carp
along with two haplotypes of Ropsha common carp, strain MM. The third lineage (III) was formed by the haplotypes of three
individuals of Ropsha common carp strain MM, all representatives of Ropsha common carp strain BB, Hungarian common carp, Ac
Amur wild common carp, and Don and Volga wild common carps. Statistically significant amino acid differences were observed
only for the sequences, corresponding to haplotypes of lineage III, and the sum of sequences of lineages I and II. Effectiveness
of different types of markers to differentiate the two subspecies of European and Amur wild common carp (C. c. carpio and C. c. haematopterus) is discussed, as well as the issues of the origin and dispersal of Russian common carp and wild common carp breeds. 相似文献
12.
Tamara S. Al-Qudah Rida A. Shibli Feras Q. Alali 《In vitro cellular & developmental biology. Plant》2011,47(4):496-505
A protocol for in vitro propagation of the wild germander (Teucrium polium L.) was developed. In vitro plants were developed from ex vitro axillary buds. Then, shoot tips were excised and established on Murashige and Skoog medium. Proliferation of shoots was tested
with different levels of 6-furfurylaminopurin, 6-benzyladenine, or thiadiazuron. The highest proliferation of T. polium was obtained when 6-benzyladenine and 6-furfurylaminopurin were used at 2.0 and 1.6 mg l−1, respectively. Thiadiazuron gave the lowest response for shoot proliferation. Rooting was experimented at different levels
of Indol-3-butric acid, Indol-3-acetic acid, or 1-naphthaleneacetic acid. 1-Naphthaleneacetic was the only growth regulator
which promoted root induction. Rooted plants were acclimatized successfully with 75% survival and grown in the greenhouse.
In vitro- and in vivo-grown plants were analyzed for essential oil production. In vitro-grown T. polium on MS medium supplemented with 6-benzyladenine and 1-naphthaleneacetic gave higher oil yield than that grown on hormone-free
Murashige and Skoog medium. In vivo (wild)-grown T. polium produced different oil yield when collected in different months (April and October). β-caryophyllene, used as a marker compound
in the essential oil, was identified and quantified by gas chromatography (GC) analysis. Gas chromatography/mass (GC-MS) spectrometry
analysis was also used to identify other components of in vitro cultures and to compare with in vivo-grown plants. 相似文献
13.
S. E. Dawson 《Kew Bulletin》2008,63(3):517-517
Summary The name Pavetta modesta (Hiern) S. E. Dawson is a later homonym of P. modesta Bremek. Pavetta crystalensis is proposed as a new name. 相似文献
14.
Nikoleta Karaiskou Maria Lappa Stefanos Kalomoiris George Oikonomidis Chariklia Psaltopoulou Theodore J. Abatzopoulos Costas Triantaphyllidis Alexander Triantafyllidis 《Conservation Genetics》2011,12(5):1299-1311
The ability to detect genetic differences both in space and time is crucial for conserving genetic variation. It can reveal
genetic diversity and genetic composition changes of declining native populations that are supported through stocking with
captive bred individuals. The present study was designed to analyse the temporal stability of a declining common carp (Cyprinus carpio) population from Lake Volvi (North Greece). Polymorphism was evaluated using seven microsatellite loci at two sampling time
points (separated by 12 years). The genetic variability of four additional populations (from two rivers and two lakes) in
Northern Greece was also investigated for comparison. Heterozygosity values (0.692–0.868) and allelic richness (8.530–11.148)
were high for all studied populations and comparable to other European populations. However, the analysis of temporal common
carp samples from Lake Volvi revealed a significant change in their genetic composition and admixture analysis demonstrated
significant introgression of stocked individuals into the native population. Both temporal and point estimate methods revealed
low effective size (Ne = 61–171.3) for this population, possibly a result of an ancient genetic bottleneck that led to population decline and/or
recent anthropogenic interventions. This low Ne has rendered the native population vulnerable to alteration of its genetic composition. Our study demonstrates that enhancement
programs should be applied cautiously, especially for small populations. Moreover, it underlines the need for temporal analyses,
which may contribute to the evaluation of previous management policies and to future decision making. 相似文献
15.
16.
H. L. E. Magariños C. Sahr S. D. C. Selaive M. E. Costa F. E. Figuerola O. A. Pizarro 《Applied Biochemistry and Microbiology》2008,44(3):300-304
The purpose of this study was to determine the inhibitory effects of cranberry juice on pathogenic microorganisms. The microorganisms
analyzed were Escherichia coli from patients with urinary infections, Salmonella spp., Listeria monocytogenes, Pseudomona aeruginosa, and Staphylococcus aureus. The disc method was used to determine the sensitivity of bacteria to cranberry juice (CJ, both concentrated and diluted).
A lawn of 106 cfu/ml was grown on agar surfaces in Petri dishes and on Whatman discs that had been previously saturated with CJ and CJ
: water. 1 : 1 to 1 : 50 juice solutions had been placed on the discs, which were cultured and incubated. The results indicated
that S. aureus was more susceptible to cranberry juice inhibition than the other microorganisms. L. monocytogenes was the most resistant to the inhibitory action of cranberry juice, showing a significant difference from the inhibition
of P. aeruginosa, uropathogenic E. coli, Salmonella spp., and S. aureus. This study also demonstrated that the inhibitory activity of cranberry juice for E. coli took place up to a dilution of 1 : 20.
Published in Russian in Prikladnaya Biokhimiya i Mikrobiologiya, 2008, Vol. 44, No. 3, pp. 333–336.
The text was submitted by the authors in English. 相似文献
17.
N. Yu. Markelova 《Microbiology》2010,79(6):777-779
Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached
to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection
and public health is discussed. 相似文献
18.
As a step toward greater understanding of the genetics of verticillium wilt resistance in plants, we report the sequencing
of a candidate wilt resistance gene, mVe1, from the mint diploid model species, Mentha longifolia (Lamiaceae). mVe1 is a putative homolog of tomato (Solanum lycopersicum L.) verticillium wilt (Ve) resistance genes. The mVe1 gene has a coding region of 3,051 bp. The predicted mVe1 protein contains a leucine-rich repeat domain, a common feature of plant disease resistance proteins. We compared 13 mVe1 alleles from three mint species. These alleles shared 96.2–99.6% nucleotide identity. We analyzed four M. longifolia populations segregating with respect to mVe1 alleles and wilt resistance versus susceptibility and found one association between mVe1 genotype and wilt phenotype. We conclude that mVe1 may play a role in mint verticillium wilt resistance, but variation for resistance in our segregating progenies is likely
polygenic. Therefore, further investigations of mVe1 and identification of additional candidate genes are both warranted. 相似文献
19.
Fabián Fernández-Luqueño L. Dendooven Antonio Munive Langen Corlay-Chee Luis Manuel Serrano-Covarrubias David Espinosa-Victoria 《Acta Physiologiae Plantarum》2008,30(4):545-552
We studied morphological changes over time by nodules formed on the root system of the common bean (Phaseolus vulgaris L.). Two cultivars, Bayomex and Cacahuate 72 with growth habit Type I and the Rhizobium etli strain CE-3 were used. The results showed the collapse of the infected zone, degradation of the cell walls and membranes,
changes in the number and distribution of the starch granules, appearance of protein granules, and disintegration of the central
tissue of the nodule with ageing. Additionally, we describe the influence of time on the progress of the nodular senescence. 相似文献
20.
Swasti S. Swain Tapasi Tripathy Pradipta K. Mohapatra Pradeep K. Chand 《In vitro cellular & developmental biology. Plant》2010,46(2):134-141
In vitro regeneration of black nightshade (Solanum nigrum L.) plants was achieved through callus-mediated shoot organogenesis followed by 30 d indoor ex vitro adaptation to nutritional stress under environmental ambience and thereafter 6-d outdoor acclimatization in pots prior to
field establishment. Relevant physiological parameters including pigment content, chlorophyll a fluorescence, net photosynthetic rate (P
N), transpiration rate (E), and stomatal conductance (g
s) of in vitro-regenerated plants were investigated during the course of ex vitro adaptation. During the first 4 d of indoor transplantation to potting substrate, there was a marginal reduction in the leaf
chlorophyll and carotenoid contents but P
N and E were strongly reduced. The stomatal conductance and E/P
N ratio were significantly higher in plants up to 20 d of indoor adaptation than those of comparable age grown naturally from
seeds. The shape of the OJIP fluorescence transient varied significantly with acclimatization, and the maximum change was
observed at 2.0 ms. The 2.0 ms variable fluorescence (V
j), 30 ms relative fluorescence (M
0), photon trapping probability (TR0/Abs), and photosystem II (PSII) trapping rate (TR0/RC) showed initial disturbance and subsequent stabilization during 30 d of indoor acclimatization. Energy dissipation (DI0/RC) and electron transport probability (ET0/TR0) showed an initial phase of increase during the 4 d after plants were transplanted outdoors. During the 6-d outdoor acclimatization
after transfer of plants to soil, no significant change in total chlorophylls and carotenoids, E, and g
s were observed, but P
N improved after reduction on the first d. The OJIP-derived parameters experienced change on the first d but were stabilized
quickly thereafter. There was no significant difference between outdoor acclimatized plants and those of the seed-grown plants
of comparable age with respect to photosynthetic and fluorescence parameters. Direct transfer of plants without indoor acclimatization,
however, showed a completely different trend with respect to P
N, E, and OJIP fluorescence transients. The bearing of this study on optimizing micropropagation is discussed. 相似文献