Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 164

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Цель работы состояла в познании некоторых факторов, обусловляющих массовое появление элафостронгилоза в Беловежской Пуще. Исследовано сезонную динамику удаления личинок 1 стадии Elaphostrongylus cervi, а также видовой состав и экологию улиток, являвшихся посредственными хозяевами упомянутого нематода, а также экстенсивеость, интенсивность и сезонную динамику их заражения. В сезонной динамике удаления личинок 1 стадии Е. cervi оленями отмечено наличие 2 пиков. Первый, меньший, наблюдался в феврале, затем удаление личинок значительно понижалось, чтобы в мае совершить огромный прыжок и достичь второго пика. Установлено 5 видов сухопутных личинок, являвшихся посредственными хозяевами Н. cervi в спонтанной инвазии. Это были: Succinea putris, Bradybaena fruticum, Perforatella bidentata, Arion subfuscus и Zonitoides nitidus. Экстенсивность спонтанного заражения улиток личинками Е. cervi колеблется в пределах 6,6—27,4%. Наивысшую интенсивность инвазии, составляющую 557 личинок, отмечено у улиток S. putris. С июня по август экстенсивность заражения улиток S. putris личинками Е. cervi удерживалась на сближенном уровне, а в сентрябре показывало тенденцию к понижению. Наиболее существенную роль в распространении элафостронгилоза среди оленей Беловежской Пущи играют улитки S. putris и В. fruticum из-за своей экологии и наиболее многочисленного появления в охотничьем угодье.
Examinations were carried out in Białowieska Forest, Borecka Forest, Lower Silesian Forest, woods in Olsztyn District, Słowiński National Park, and in experimental hunting areas of the Forest Research Institute in Iława and of the Warsaw Agricultural University in Rogów. Samples of the skin from the ear and nose were taken from 136 shot roe deers. Skin samples were cut into 1-2 mm pieces, incubated in a physiological solution in 25°C for 24 hours and examined for the presence of microfilariae. Microfilariae of Dipetalonema rugosicauda were found in roe deers in all examined hunting grounds. Prevalence of invasion oscillated from 6,6% to 57,1 %. The wide dispersion of D. rugosicauda in Poland is caused by common occurrence in our country of the intermediate host and vector of this nematode - tick Ixodes ricinus.
The objective of the study was to establish possibilities of the development of the I stage larvae of E. cervi in fishes and amphibians, and possibilities of paratheny in the organism of these animals. In the alimentary tract of the fishes both the I stage and the invasive (i.e. III stage) larvae can not cross the intestine barrier and undergo digestion. However, in the frag organism the I stage larvae of E. cervi are capable of crossing the wall of the alimentary canal and of going through a part of their development, though not attaining the II stage. The invasive larvae fed to the frogs penetrate under the peritoneum, into the mesenterium and the muscles and there they survive inside cysts. Frogs as parathenic hosts for E. cervi can be dangerous for predators feeding on amphibians. The larvae of E. cervi liberated in their organism can pass through the cerebral phase of their development thus causing neural clinical symptoms.
Single doses (from 300 to 1000 larvi per an animal) of invasive larvae E. cervi Cameron, 1931, obtained from experimentally infected snails Helix pomatia L. were given to 17 guinea pigs and 17 golden hamsters. Clinical nervous symptoms in the form of paresis and paralysis of limbs occurred only in the guinea pigs which were given a dose of 1000 larvi. These animals died in the period from the 75th to 117th day of infection. From their central nervous system single adult males and females of E. cervi were isolated. In the lungs and mesenteries of 2 dead pigs live larvae of E. cervi were found. This fact proves that the guinea pig can fulfil the role of a final and a paratenic host of E. cervi. No clinical symptoms were noticed in any hamster. In hamsters dissected on the 7th day of infection live larvae of E. cervi were found in the mesentery and in the fleshy part of the diaphgram. After 14 days the larvae found both in the mesentery and in the diaphragm were dead and surrounded by cellular infiltration. A strong tissue reaction of the hamster after the administration of E. cervi larvae is responsible for the larvae destruction and resorption.
Dirofilariosis caused by the Dirofilaria repens nematodes is widely dispersed in southern Europe, Asia and Africa among dogs, cats, other carnivores and occasionally, humans. The first case of D. repens infection, found in Poland in 2007, concerned humans. In 2009, dirofilariosis was first registered in dogs in 3 focuses in central Poland, Warsaw, Pruszków and Żyrardów, whose range grew considerably with the subsequent identification of D. repens microfilariae in 119 dogs in Warsaw and 18 districts of the Mazowieckie Province. The microfilariae of D. repens were found in blood samples taken from 1588 dogs from all 16 provinces of Poland. D. repens was also recently detected in a mixture of Culex pipiens and Aedes vexans mosquitoes collected in Mazowieckie Province using Real Time PCR. The results of this study confirms the acclimatisation of D. repens on the territory of Poland and a possibility for it to close its life cycle in domestic species of mosquito.
Three 1 year old sheep were infected per os with 1000, 2000, and 13000 invasive larvae of Elaphostrongylus cervi. Animals did not show any clinical symptoms of invasion. No larvae of this nematode were found in the samples of faeces during the experiment. During post mortem examination of infected sheeps no parasites or their larvae were found in tissues, and no pathological lesions caused by parasites were observed.
Faeces of red deers from Białowieża Forest containing first stage larvae of Elaphostrongylus cervi have been stored during live years in -20°C. After this time 52% of the larvae survived. These larvae were fully alive and in experimentally infected snails Helix pomatia developed to the infectious stage.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 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.