Angewandte Parasitologie最新文献

Ivermectin is lethal to Bulinus (Physopsis) globosus, Biomphalaria pfeifferi, and Lymnaea natalensis at concentrations of 0.08 micrograms/ml and above. Studies show that these snails will not recover from a 24 h exposure to 2.00 micrograms/ml of Ivermectin in the laboratory at 28 +/- 2 degrees C. A time dependent toxicity to snails was recorded and an exposure of adult snails to sub lethal concentrations significantly reduced the number of eggs laid (r = -0.08, t = 2.64, P less than 0.05).

Cambendazole 10(-4) M significantly reduced the level of glycogen in both the parasites. Lactic acid level was found enhanced. Oxygen consumption was suppressed by 63 and 94% in A. galli and H. gallinae, respectively, by 10(-4) M cambendazole. Haloxon did not cause any significant change in glycogen and lactic acid level in either parasite, but reduced oxygen consumption by 23 and 31% in Ascaridia galli and Heterakis gallinae, respectively.

A review is given on the situation of resistance in the German cockroach (Blattella germanica) to insecticides during the last 15 years in the GDR, and conclusions are drawn for the future. From 23 samples trapped in various localities and subsequently reared in the laboratory, susceptibilities were measured against lindane, pyrethrin + PBO, trichlorfon, dichlorvos, and propoxur, the most used insecticides against cockroaches in our country. Detection of resistance was done with discriminating doses and the degree of resistance was measured with the doses-mortality method in deposit tests. In no case we found any resistance to propoxur but, for the first time, strains with a low resistance to dichlorvos. There was a distinct increase in the resistance to lindane, trichlorfon and pyrethrins + PBO during the lost years. A strain selected with pyrethrins in the laboratory showed marked group resistance to all tested pyrethroids (permethrin, cyfluthrin, cypermethrin, tetramethrin, deltamethrin, bioresmethrin, bioallethrin), but no cross resistance to the other insecticides.

Eggs of opisthorchiid flukes have very characteristic muskmelon-like surface structure of their shells and can be differentiated using this mark from eggs of heterophyid flukes. Surface structure and morphological details in operculum and abopercular end can be observed using scanning electron microscopy. Eggs recorded very often in stool of Laotians belong mostly to Opisthorchis viverrini and sporadically to Metagonimus yokogawai.

Trypanosoma barrettoi sp.n. is described from the blood of the armored catfish Hypostomas paulinus Ihering, from the State of São Paulo, Brazil. The total length averages 40.22 microns, of which 14.22 microns is free flagellum.

The morphology of L4 of Cylicostephanus minutus, Cylicotetrapedon bidentatus, Petrovinema poculatum, Cylicocyclus radiatus, C. triramosus, Cylicodontophorus euproctus, C. mettami, C. mongolicus, Poteriostomum imparidentatum, Gyalocephalus capitatus and Craterostomum acuticaudatum is discussed. The species are named in accordance with the new system, which is outlined in the introduction. The criteria for the identification of larvae killed during their 4th skinning include distinctive marks occuring in the 4th and 5th stages: gut morphology, position of cervical papillae, excretory opening, morphology of the caudal part of the female. For L4, generic characteristics have not been distinguished (except Petrovinema spp.). Larvae of small Strongylinae species are similar to those of Cyathostominae.

The kidneys of rats, experimentally infected with Trichinella spiralis were studied by means of light and fluorescent microscopy. The results obtained suggest that this is a case of a proliferative intra- and extracapillary nephritis. Highest intensity of the pathological process was noted between the 30th and 50th day of the infection. The immunofluorescent reaction of kidney glomeruli demonstrated that the immune complexes were located predominantly in the basal membrane and the mesangium. The serological investigation showed that the maximum level of circulating immune complexes existed between 14th and 21st day after the infection.

In vitro studies with Paramphistomum microbothrium indicated that the trematode is capable of synthesizing its complex lipids using exogenous substrates. U-14C glucose and 2-14C acetate were predominantly incorporated into phospholipids while 1-14C oleic acid and U-14C palmitic acid appeared more in the neutral lipids. A large proportion of the labelled acetic acid incorporated into neutral lipids appeared in the triglycerides. P. microbothrium is capable of synthesizing its cholesterol de novo.

It was established that antigens of diphyllobothriids entered the organisms of nestlings of gulls (Larus fuscus) and terns (Sterna hirundo) through the intestine. In terns, the most intensive neutralization of parasite antigens was found in the intestine inducing a weak response of the immune system. In gulls, there was no complete neutralization of the parasite antigens in the intestines. The antigens penetrated into the blood stimulating a response of the immune system. The intensity of the local immunity of terns seems to result from the absence of invasion in adult birds.