Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 13

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  parasite community
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
This study investigated the factors (i.e., season, locality, sampling year, total length and maturity stage of the hosts) that might influence the structure of parasite populations and communities in the clingfish Gobiesox marmoratus. The parasite community was described and analyzed using numerical descriptors, such as prevalence, intensity and species richness, between factors previously mentioned. A total of 260 clingfish were collected from 2 localities of central Chile, four seasons and during 3 year cycles (from July 2006 to July 2009). In the whole clingfish sample, 668 parasites were found, which belonged to 14 parasite taxa; 9 of them were new records in G. marmoratus. Parasite infracommunity richness ranged 0–3 species, although 1 trematode species, Helicometrina nimia, represented 80% of all parasites collected and was the most abundant and prevalent parasite species. The average of parasite abundance and intensity (± SD) was 2.5 ± 8.2 and 7.5 ± 12.7, respectively. Generalized linear model showed that parasite communities were influenced by season, locality, sampling year, and maturity stage when considering the abundance and intensity of parasites. For the parasite richness, only the locality and maturity of fish was determinant for explaining the differences. The populations and communities of the parasite variations were variable due to differences in fish body length because prevalence, abundance and intensity of parasites significantly correlated with the fish body length. Concordantly, maturity fish were longer than immature fish. Thus, clingfish from El Tabo were longest and mature, which harbored higher parasite richness than those fish from Las Cruces.
The blood parasite diversity was studied in paddyfield warblers (Acrocephalus agricola) breeding in NE Bulgaria, SW Russia and S. Kazakhstan. Nine cytochrome b gene lineages were recorded, 4 belonging to Haemoproteus spp. and 5 to Plasmodium spp. The overall prevalence of haemosporidians was 33.3%. The composition of parasites varied geographically, with six lineages recorded in Russia, five lineages in Bulgaria and two lineages in Kazakhstan. Two lineages are described for the first time, i.e. ACAGR1 (belonging to Plasmodium sp. and recorded from a single bird in Russia) and ACAGR2 (belonging to Haemoproteus sp., recorded from Bulgaria and Russia). The latter lineage is the most widespread parasite in the Bulgarian population, scarce in Russia and absent in Kazakhstan. It is supposed that ACAGR2 has originated from the widespread lineage ACDUM1 differing from it by a single nucleotide. One lineage only (ACDUM2) occurs in all the three populations studied and is a nonspecific parasite known from various passerines. Six of the registered lineages have been found in a single population of A. agricola and also represent non-specific parasites occurring in a wide range of passerine birds. Their records in A. agricola may indicate the high transmission rate of these parasites in the habitats where this host co-occurs with other passerines. The variation of the composition of the haemosporidian parasite communities through the breeding range of A. agricola makes up heterogeneous selection pressures that may drive intraspecific variation in important life-history traits.
Communities of parasites of European perch from lake Łebsko were studied and compared with similar communities from the Polish coastal zone. Parasites comprised 18 autogenic and 5 allogenic species. Most individual parasites belonged to allogenic species and were in larval stages. The majority of specimens were eye parasites with Tylodelphys clavata as the eudominant species. The dominant species, Acanthocephalus lucii, belongs to the intestine parasite community. Three marine species were found: Bothriocephalus scorpii, Hysterothylacium aduncum and Echinorchynhus gadi. The results indicate that the parasite fauna consists mostly of freshwater species, common in various types of European waters, while marine species were rarely observed.
A study was carried out in a shallow, eutrophic Oświn Lake, within Seven Islands Reserve (north-eastern Poland), in order to determine the infection of fish with monogeneans as sensitive indicators of water quality. This paper presents comparative analysis of the occurrence of Monogenea in fishes from two, distinctly separated pools of the lake, differing in environmental conditions. The impact of fish size and sampling season on the infection parameters was also analyzed. Material and methods. In 1998 and 1999, a total of 1091 fish representing 8 dominant species were examined. Samples were collected four times a year (in May, July, August, and October) simultaneously from the eastern and western parts of the lake. Results. 16 species of Monogenea (and some unidentified specimeus) occurred in the fish examined, most of them from the Dactylogyridae family: Dactylogyrus sphyrna, D. auriculatus, D. intermedius, D. anchoratus, D. falcatus, D. tincae, D. wunderi, D. zandti, D. difformis, D. nanus, D. distinguendus, D. crucifer, D. caballeroi. Furthermore, Tetraonchus monenteron (Tetraonchidae), Gyrodactylus elegans (Gyrodactylidae), and Paradiplozoon megan (Diplozoidae) were detected. Monogenea occurred abundantly on the gills of pike, roach, rudd, white bream, carp bream and crucian carp, but rather sporadically in tench and perch. The highest species variety and diversity of monogenean guilds were detected in carp bream and roach. It was proved that D. crucifer and D. difformis were significantly more abundant in the western pool compared to the eastern one. Infection of fish with Dactylogyridae was season-dependent, contrary to the infection of pike with T. monenteron. Intensity of infection of white bream with D. sphyrna and roach with D. crucifer increased with fish body length; such a relationship did not appear for the other monogeneans and their hosts. Conclusion. Presence of common Monogenea in the fish examined, lack of rare species, poor diversity of monogenean guilds and relatively low infection rate could be connected with the low stability of the lake environment. Location-dependent occurrence of D. crucifer and D. difformis indicated that the exchange between fish groups from the eastern and western parts of the lake is limited.
A diagnostic deworming of 21 Przewalski horses, free−living in the Chernobyl exclusion zone Ukraine, and of six stabled domestic horses, has been conducted eighteen years after the Chernobyl nuclear disaster. This survey yielded 31 species (of 5 families and 3 classes, 28 species of nematodes, 1 species of cestodes, and 2 larvae of botflies). A total 29 and 19 helmith species has been recorded in the Przewalski horse and domestic horse respectively. Only six helmith species were common for the two horse species. Species from the family Strongylidae constituted the dominant helmith group. Four cyathostomine species (Cyathostomum catinatum, Cylicostephanus minutes, C. longibursatus, Cylicocyclus nassatus) formed the majority of helmith parasites both in the Przewalski and domestic horses. The presently reported study revealed that Przewalski's horses keep their typical biological features and high resistance to parasitic infections. A substantial growth of heard was observed as well as good clinical health state of horses. This can be an argument favouring the use of Przewalski horses in re-naturalization of ecological disaster areas.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.