Ograniczanie wyników

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

Znaleziono wyników: 19

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:  larval stage
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
The infection patterns of parasites are often tied to host behavior. Although most studies have investigated definitive hosts and their parasites, intermediate host behavior may play a role in shaping the distribution and accumulation of parasites, particularly the larval stages. In an attempt to answer this question, more than 4,500 pulmonate snails were collected from 11 states in the mid-Atlantic and Midwestern United States in the summer of 2012. These snails were necropsied and echinostome metecercariae were commonly observed infecting the snails as 2nd intermediate hosts (20.0%). The snails included species of 3 genera with distinct differences in the infection patterns of Echinostoma spp. metacercariae among them. Physa spp. (comprising of P. acuta and P. gyrina) snails exhibited a significantly higher prevalence of infection (23.5%) than both Lymnaea columella (11.6%) and Helisoma spp. (comprising of H. anceps and H. trivolvis) (14.2%; P < 0.05), with no difference in prevalence observed between the latter 2 genera (P > 0.05). The intensity of metacercariae within the snail hosts was significantly different between the 3 genera (P < 0.05), with L. columella having the highest intensity (24.3 ± 5.6), followed by Physa spp. (15.2 ± 1.5) and Helisoma spp. (5.0 ± 0.9). Differences in prevalence and intensity were also observed when the different snail families co-habited the same body of water. The disparities in infection patterns are likely due to distinct differences in the behavioral and feeding ecology of the snail hosts.
The morphogenesis of the digestive tract and swim bladder of ide Leuciscus idus (L.) was analyzed using histopathological methods. At the moment of hatching, ide larvae are more advanced in their development than the larvae of other teleost fish species. Endo-exogenous nutrition began on day 2 post hatch. At this stage of development, the intestine was lined with a single-layered cylindrical epithelium, and both liver and pancreas began to function. Signs of digestion and enterocyte protein and lipid absorption were observed on day 6 of development. The mucus cells in the mouth, esophagus and gullet produced neutral and acidic mucins. Intestinal cuboid cells appeared on the fourth day and only began secreting acidic carboxyl and sulfate mucins. The differentiation of the air duct and the posterior chamber of the swim bladder was observed on the day of hatching, and the bladder inflated after 24 hours. The anterior chamber began to form on day 9, and it inflated with gas between days 23 and 25 of larval development.
Over a two-years period, a survey was carried out in order to increase the knowledge of digeneans parasitising the commonest intertidal gastropods on the Patagonian coast, Southwestern Atlantic Ocean. A total of 4,725 gastropods were examined. Six species of digenean parasitising four snail species were found; four of them were registered for first time: Maritrema sp. 1 (Microphallidae) in Crepidula dilatata (Calyptraeidae), Parorchis sp. (Philophtalmidae) and sporocyst of Renicolidae in Trophon geversianus (Muricidae), and Diphterostomum sp. (Zoogonidae) in Buccinanops globulosus (Nassariidae). Two other species were found in Siphonaria lessoni (Siphonariidae): Maritrema sp. 2 and Hemiuridae. One snail species, Tegula patagonica (Trochidae) was not parasitised. These gastropods act as first intermediate host, and C. dilatata, S. lessoni and B. globulosus also frequently host metacercariae within the sporocyst. Overall prevalences varied from 0.16% of Diphterostomum in the intertidal population of B. globulosus to 33.45% of Maritrema sp. 1 in C. dilatata.
The morphology of the third larval stage of Morica hybrida Charpentier, 1825 (Tenebrionidae: Pimeliinae, Akidini) is described and illustrated. The description is based on diagnostic characters of Tenebrionidae classification on head, legs and ninth abdominal segment. The larva of Morica hybrida shows numerous affinities with previously described larvae of Pimeliinae and is clearly included within tribe Akidini. The larva of M. hybrida shows a high similarity with the larva of M. favieri, although they differed by the presence or absence of additional small spines in distal part of ninth abdominal segment, and the shape of the margin of labrum. In addition, similarities with larvae of Akis spp. corroborates the proximity of these two Mediterranean genera of Akidini.
The last larval stage of Heliotaurus ruficollis Fabricius, 1781 (Tenebrionidae: Alleculinae, Omophlini), a subterranean detritivore, is described in detail. The larva of H. ruficollis has the distinguishing characters of the subfamily Alleculinae and the tribe Omophlini, and it may be distinguished from the larvae of Omophlus species by the more rounded apex of tergum 9 and the fact that the ventral portion of tergum 9 is at the same level than sternum 9.
A cross – sectional study of bovine, porcine and dog cysticercosis was carried out in Bukuru Plateau State Nigeria,in 2010 using Gyel Bukuru abattoir, Fwagul and Kuru trade centre slaughtering abattoir, as study areas. Two hundred and twenty-five samples were collected at random comprising of seventy-five samples each from cattle, dog and pig respectively, where twenty-five samples were taking for raw meat, cooked meat and feaces in relation to the sex of the animals examined. The overall prevalence rate of 28 (12.44 %) was recorded out of the total sample of 225. Raw meat records 10 (4.44 %), cooked meat record 7 (3.11 %) and feaces records 11 (4.98 %) infection rate. X2 analysis show no significant difference in the prevalence rate of cysticercus in meat and cyst in feaces of the examined animals (p > 0.05). There was no record of infection in cattle, both in beef and feaces in different sexes of the cattle examined, sex specific incidence rate obtained in both studies did not differ significantly (p > 0.05). The female animal studied had the highest infection rate of 17 (60.71 %).There was significant difference in tapeworms encountered with the meat and feaces examined (p < 0.05) Taenia solium had the highest infection rate of 14 (6.22 %), Dipylidium caninum had 12 (5.33 %) with the least infestatioin recorded in T. hydatigena 2 (0.89 %). Hence no record of T. saginata infection was encountered in the present study. However mixed infection was recorded in Dog with T. hydatigena & D. caninum.
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.