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1

Detection of Aphanomyces astaci in spiny-cheek crayfish from selected water reservoirs of north-western Poland

100%
Adamkowska N., Kielpinska J., Panicz R., Smietana P.
Medycyna Weterynaryjna
|
2018
|
tom 74
|
nr 06
Aphanomyces astaci is a fungus-like oomycete agent responsible for an illness called crayfish plague, reaching 100% mortality in infected animals. Therefore, the aim of the work was to detect and estimate the rate of infection of spiny-cheek crayfish (Orconectes limosus) by A. astaci in selected water reservoirs of north-western Poland, as this crayfish is described as a main cause of crayfish plague. The material for the study were 54 spinycheek crayfish individuals from 3 sites in Poland: Trzebiocha River, Lake Sominko and Lake Dąbie. A total of 162 samples (muscle samples were taken from abdomen, legs and carapace) were taken and used for DNA extraction followed by PCR and bidirectional sequencing of 5.8S ribosomal RNA gene. The electrophoretic separation of the PCR products confirmed the presence of A. astaci in 17 samples (Trzebiocha River and Lake Dąbie). Lake Sominko proved to be a zone free of the investigated pathogen. The collected information on the presence or absence of A. astaci in the investigated reservoirs might be used for restocking purposes.
2

Morphometrics, fecundity, density, and feeding intensity of the spinycheek crayfish, Orconectes limosus (Raf.) in natural conditions

100%
Chybowski L.
Archives of Polish Fisheries
|
2007
|
tom 15
|
nr 3
The subject of the study was three populations of spinycheek crayfish, Orconectes limosus (Raf.) from lakes Staw Płociczno, Dgał Wielki, and Hańcza. The aspects of the spinycheek crayfish studied were the morphometric characters of females and males, individual absolute fecundity, sex ratio, size structure, density, biomass, and feeding intensity in an annual cycle. It was determined that the body proportions of males in forms I and II differed significantly, while the body proportions of female spinycheek crayfish were similar to those of form II males but different from the body proportions of form I males. The crayfish investigated in the current study had a lower individual absolute fecundity than did spinycheek crayfish of the same body weights from other Polish basins. The crayfish daily food ration exhibited a very strong relationship with the stomach fullness index and water temperature. The empirical formula of this relationship (ln Rd P = 0.397 + 0.094 t + 0.614 ln If) permitted estimating the daily food ration. The crayfish fed most intensely from the May to October period, during which they consumed in excess of 80% of their annual ration. The primary dietary component of the spinycheek crayfish was plant matter. Annually, the crayfish population consumed barely 0.27% of the wet weight of the aquatic vegetation in its range of occurrence.
3

Cross-species amplification of microsatellite markers in the invasive spiny-cheek crayfish [Orconectes limosus]: assessment and application

100%
Hulak M., Kaspar V., Kozak P., Buric M., Filipova L., Petrusek A.
Journal of Applied Genetics
|
2010
|
tom 51
|
nr 1
73-78
The North American spiny-cheek crayfish, Orconectes limosus (Cambaridae), endangered in its native range, is a widespread invasive species in European waters and conservationally important carrier of crayfish plague. However, its population structure is poorly known, and no informative genetic markers for the species are available. We tested cross-species transfer of microsatellite loci to spiny-cheek crayfish from 5 other crayfish species. Variability of 10 successfully amplifying loci derived from 4 species was then tested in 60 individuals of O. limosus originating from 3 natural populations: the river Danube at Bogyiszló in Hungary, a pond in Starý Klíčov, and the brook Černovický, both in the Czech Republic. The allele number within the populations ranged from 4 to 10 alleles per locus, while heterozygosity levels varied from 0.650 to 0.900 for Ho and from 0.660 to 0.890 for He. No linkage disequilibrium and no null alleles were detected. The selected markers are useful for assessing population structure, intraspecific variation, and paternity studies in spiny-cheek crayfish.
4

Determination of the rate of growth of spiny-cheek crayfish, in lake Woswin on the basis of exuviae using polymodal length-frequency distribution analysis

100%
Smietana P.
Advances in Agricultural Sciences
|
2008
|
tom 11
5

Histological analysis of the annual cycle of gonad development in the male spin-cheek crayfish Orconectes limosus Raf.

100%
Chybowski L., Juchno D.
Archives of Polish Fisheries
|
2002
|
tom 10
|
nr 2
Histological analyses were conducted of the annual cycle of male gonads of spiny-cheek crayfish Orconectes limosus Raf. Although changes in the male gonads throughout the year are clearly evident, they are not uniform in all males. Spiny-cheek crayfish mate mainly in the autumn from September to November. After mating, the gonads of male crayfish can be divided into two groups according to their histological structure. In the first group there is an abundance of sperm in the gonads, while the testicular tubules in the second group are either empty or contain a small amount of sperm. This division remains until May. In May, the histological picture of the gonads is uniform, and there are either very few or no tubules containing sperm. In June O. limosus males occur in two forms. The histological pictures of first- and second-form male gonads do not differ. However, beginning in July and also in August and September, the gonads of first- and second-form males do differ. First-form male crayfish gonads contain more sperm than those of second-form males. From October onwards, all of the males are first-form, and primarily spermatids and sperm are visible in the gonads. The possibility that the spiny-cheek crayfish mates twice annually, once in autumn and again in spring, is discussed based on changes observed in the histological picture of the gonads.
6

Estimated population abundance of catchable signal crayfish [Pacifastacus leniusculus [Dana]] and spiny-cheek crayfish [Orconectes limosus [Raf.]] in lake Pobledzie [Northeastern Poland]

100%
Krzywosz T., Ulikowski D., Traczuk P.
Archives of Polish Fisheries
|
2006
|
tom 14
|
nr 1
In 2004, monitoring catches were performed on signal crayfish, Pacifastacus leniusculus (Dana) and spiny-cheek crayfish, Orconectes limosus (Raf.), in order to estimate the abundance of the catchable populations in Lake Pobłędzie (northeastern Poland). Catches were performed using 58 Evo traps along a part of lake with an area of 1.65 ha. In catches conducted on September 6 and 7, a total of 479 specimens of signal crayfish and 29 spiny-cheek crayfish were caught, marked, and released. After twelve days, repeat catches were conducted during which 476 specimens of signal crayfish, including 66 marked specimens, and 36 specimens of spiny-cheek, including 5 marked specimens, were caught. The average total length of the caught signal crayfish was 11.7 ± 1.06 cm (7.6 - 15.0 cm), while that of the spiny-cheek species was 9.3 ± 0.65 cm (7.5 - 10.7 cm). The average catchable population abundance per unit of studied surface area was calculated at 2094 specimens ha⁻¹ for signal crayfish and 127 specimens ha⁻¹ for spiny-cheek crayfish. Taking into consideration that this method underestimates the population abundance of crayfish from the lower size classes, it is estimated that the actual catchable population abundance in Lake Pobłędzie might be higher by about 25%.
7

Bioaccumulation of DDT and its metabolites in the Miedzyodrze ecosystem, Poland

80%
Tomza-Marciniak A., Witczak A.
Polish Journal of Environmental Studies
|
2009
|
tom 18
|
nr 3
467-474
The aim of this study was to estimate the degree of DDT and its metabolite bioaccumulation (biotasediment accumulation factor, BSAF and biota-water accumulation factor, BCF) in certain aquatic biota collected from the lower Oder River. The study comprised surface water and sediments, as well as soft tissue of compressed river mussel (Anodonta complanata) and certain organs of roach (Rutilus rutilus) and spinycheek crayfish (Orconectes limosus). Regarding a 30-year-old ban on DDT use in Poland, relatively low concentrations of the compound were expected. DDT and its metabolites were detected in all the examined samples. ΣDDT levels in water and sediments averaged 0.157 ± 0.068 µg/dm³ and 11.478 ± 2.292 µg/kg d.w., respectively. Roach organs contained higher levels of these compounds than crayfish and bivalves. DDT was accumulated mainly in the liver and gonads (45.823 ± 9.845 and 19.815 ± 4.854 µg ΣDDT/kg w.w., respectively). In roach organs p,p’ DDE predominated. BSAF values for p,p’ DDE and p,p’ DDD in the liver and p,p’ DDE in the gonads exceeded the predicted theoretical value (2.4). In water and sediment samples from several sites, the DDT/DDE ratio was higher than 1, which indicated fresh input of DDT in the studied area or inhibition of its breakdown.
8

The spiny-cheek crayfish Orconectes limosus (Rafinesque, 1817) as an inhabitant of the Baltic Sea - experimental evidences for its invasion of brackish waters

80%
Jaszczolt J., Szaniawska A.
Oceanological and Hydrobiological Studies
|
2011
|
tom 40
|
nr 3
9

Evaluation of changes in the abundance of three catchable crayfish species in lake Pobledzie [Northern Poland]

80%
Krzywosz T.
Archives of Polish Fisheries
|
2006
|
tom 14
|
nr 1
The aim of the study was to learn about the character and dynamics of changes in the abundance of the catchable population of the signal crayfish, Pacifastacus leniusculus (Dana), the spiny-cheek crayfish, Orconectes limosus (Raf.), and the noble crayfish, Astacus astacus (L.), that all inhabit Lake Pobłędzie (northern Poland). During the study period of 1996 - 2005, the effectivity of crayfish catches conducted with Evo traps in the lake rose from 1.30 to 5.67 specimens trap⁻¹ night⁻¹. This indicates that crayfish abundance increased progressively. The noble crayfish was observed only in the 1999 - 2002 period and succumbed to growing pressure from both of the American species. Studies have excluded the existence of the crayfish “plague” caused by Aphanomyces astaci Schikora. The abundance of the signal crayfish, which was introduced in 1992, increased throughout the study period. The abundance of the spiny - cheek crayfish rose from 1999 to 2002. Although a slight decrease was noted in 2003, not until 2004 was a rapid decline noted in this species. A similarly dramatic decline has been noted since 2002 in the abundance of spiny-cheek crayfish in many other Polish waters. This was probably the result of an outbreak of an infectious disease particular to this species. The catch effectivity of signal crayfish (99.5% share of catches) in 2005 was 5.00 specimens trap⁻¹ night⁻¹ and was higher than the catch effectivity achieved with this species in Californian and Swedish lakes.
10

Histological analyses of gonad development in female spin-cheek crayfish Orconectes limosus Raf.

80%
Juchno D., Chybowski L.
Archives of Polish Fisheries
|
2003
|
tom 11
|
nr 1
Histological analyses were preformed to investigate the annual cycle of the ovaries of female spiny-cheek crayfish Orconectes limosus Raf. (Crustacea). In May, the crayfish ovaries were filled mainly with oocytes in the initial stage of development (previtellogenic oocytes). The histological picture of the ovaries indicated the presence of empty follicles and mature oocytes undergoing resorption. In the summer months, the volume of the oocytes gradually increased and surplus substances material began to be synthesized (phase I or endogenous vitellogenesis). The histological picture of the ovaries in August was varied; some of them contained previtellogenic and vitellogenic oocytes in phase I, while others contained mainly oocytes in phase II of vitellogenesis when the cytoplasm fills with yolk and lipid globules. In fall, winter and spring the ovaries of crayfish O. limosus were filled mainly with oocytes in phase II of vitellogenesis; these were gradually increasing in volume. The annual gonadosomatic index (GSI) was calculated in the range of 0.41 to 5.83. The percentage of previtellogenic to vitellogenic oocytes prior to spawning was 23:77, and following spawning it was 70:30.
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