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The main branches of the middle cerebral artery were defined in 16 cerebral hemispheres. It was observed that in 14 (87.5%) hemispheres, the main trunk of the middle cerebral artery bifurcated into two common branches which, in turn, branched further into cortical branches.
A total of 114 elk faecal samples from the Polesie National Park and adjacent forest districts were examined in 2013 and 2014. Three samples were positive. The positive samples were from the village of Wereszczyn, the Sobibor forest district, and the Polesie National Park and Forest district, Parczew. Morphometric examination revealed that the oocysts belong to the species Eimeria alces. This is the second identification of the parasite in elk in Poland and the fifth worldwide.
Ashworthius sidemi, a nematode belonging to the family of Trichostrongylidae, is a primary parasite of the Asian deer, mainly sika deer (Cervus nippon), with which it was introduced to Ukraine, as well as Slovakia, the Czech Republic and France. Migrating red deer carried this parasite from neighboring countries to Polish territory. Until now, in Poland, this parasite has been recorded in European bison, red deer, roe deer and fallow deer. As a result of post-mortem examinations of 10 elk, 2 of them from the Augustów Forest and Biebrza Marshes, A. sidemi were found in abomasa for the first time in Poland. The intensity of the invasions was 120 and 7 specimens, respectively. This finding of Ashworthius sidemi in elk indicates a further expansion of the focus of ashworthiosis in BiaŁowieża towards the north into the Biebrza Marshes and the Augustowska Forest. The growth of the elk population and their tendency for long distance migrations can contribute to the spread of the parasitosis in much greater distances than deer. On the basis of our own research and data from the literature, the current spread of ashworthiosis in Poland is discussed.
After dissection examination was made of 20 roe deers (in January, May, August and October), from which over 35,000 parasites, localized in subcutaneous tissue, lungs, abdominal cavity and the alimentary tract, were collected. In all 26 parasite species were found, the prevalence and intensity of infection of which are discussed in relation to the seasons of the year. Very high infection of the abomasum by nematodes was found, affecting all the roe deers examined. Compared with other regions of Poland the roe deers in the Borecka Forest are several times more intensively infected by these nematodes, mean intensity of infection being 1671 specimens. Maximum intensity of infection by these parasites occurs in August (3537 specimens) and minimum in January (750). The roe deers in the Borecka Forest have acquired O. antipini + O. lyrataeformis and S. dagestanica from elk, and also O. ostertagi + O. lyrata from European bison. In addition they are also found to share parasites with red deer (O. leptospicularis + O. kolchida and S. boehmi + S. mathevossiani).
Tereny bytowania łosia europejskiego znajdują się w części Polski północno-wschodniej i wschodniej. Jest to obszar mało uprzemysłowiony o stosunkowo czystym środowisku naturalnym bez skażeń związkami fluoru. W badaniach naszych interesowała nas jaka jest zawartość fluoru w zębach tych zwierząt oraz kształtowanie się zależności pomiędzy wiekiem a zawartością fluoru w zębach. Stwierdziliśmy wzrost zawartości fluoru w zębach wraz z wiekiem.
Polska leży w granicznym obszarze bytowania losia w Europie Środkowej. Jest to teren podmokły z rozległymi dolinami rzecznymi o małym uprzemysłowieniu i małym skażeniu emisjami przemysłowymi. Łosie bytujące na tym terenie stanowią dobry materiał do badań nad zależnością jaka istnieje pomiędzy wiekiem osobniczym a kumulacją fluoru w kości. Zależność powyższą w analizie regresji najlepiej opisuje model iloczynowy y = axb, gdzie x jest zmienną niezależną ( wiek), a y jest zmienną zależną (zawartość fluoru).
Podczas awarii reaktora w Czarnobylu w 1986 r. przedostała się do atmosfery chmura pary z radionuklidami. Niektóre z radionuklidów, ze względu na długotrwałą emisję promieniowania beta i gamma, mogą wywoływać odlegle negatywne skutki biologiczne. Duże powinowactwo do wielu produktów rozszczepienia wykazuje tkanka kostna. W celu potwierdzenia tych założeń zbadano promieniowanie gamma całych fragmentów żuchwy losi w komorze scyntylatora oraz promieniowanie beta z ekstraktu kostnego żuchwy. Otrzymane wyniki wykazały, że w badanych żuchwach łosi z terenów północno-wschodniej Polski nie doszło do retencji radionuklidów.
Population dynamics of ungulates (European bison Bison bonasus, elk Alces alces, red deer Ceruus ela.ph.us, roe deer Capreolus capreolus, wild boar Sus scrofa, non-native fallow deer Dama dama, and cattle) were analysed in the Białowieża Primeval Forest (BPF, 1250 km2), one of the largest remaining tracts of ancient mixed and deciduous forests in the lowlands of Europe. Forty percent of BPF belongs to Poland, and 60% to the Belarus Republic. Polish and Betarussian game departments inventories of ungulate numbers (1946-1993) and archival data on censuses and hunting statistics (1798-1940) are presented. The recorded ranges of densities of native wild ungutates were: European bison 0-1.5 inds/km2, elk 0-0.6, red deer 0-5.4, roe deer 0.6-4.8, and wild boar 0.2-3.8 inds/km2. Fallow deer were introduced in 1890 (maximum density reached in 1914 was 1.2 inds/km2) and were eradicated by 1920. Cattle were traditionally pastured in the Forest, and its grazing impact was heaviest in 1880-1914 (maximum recorded density 6.7 inds/km2). In 1798-1993, the community of wild ungulates consisted of three to six species, with total densities varying from < 2 to 14.4 inds/km2 (65 to 1180 kg of crude biomass per 1 km2). Roe deer, wild boar, and red deer were usually the dominants. However, in 1860-1971, cattle constituted from 15% to 80% by numbers and from 37% to 87% by biomass of all ungulates in Białowieża Forest. Data on population trends within a five-species assemblage of native wild ungu­lates were subject to multiple regression analysis to determine the roles of predation (by wolves Canis lupus and lynxes Lynx lynx), competition, food, weather variables, and humans in shaping population densities and increase rates of ungulates. Growth of the mean annual temperature had positive effect on densities of all ungulates, probably through improving food supply and feeding conditions. Bison and elk were shaped by intra- and interspecific competition for food. Bison numbers have heen significantly limited by humans, due to both uncontrolled exploitation in years of political instability and deliberate culling in years of protection. Red deer and roe deer were primarily shaped by predation from wolves and lynx, respectively. Compe­tition for food influenced red and roe deer when they had erupted after predator extermination. Wild boar was influenced predominantly by food availability, especially the highly variable crops of oak seeds.
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