In vitro anthelminthic efficacy of Dichrocephala integrifolia (Asteraceae) extracts on the gastro-intestinal nematode parasite of mice: Heligmosomoides bakeri (Nematoda, Heligmosomatidae)

<p><b>OBJECTIVE</b>To evaluate the ovicidal and larvicidal activities of aqueous and ethanolic extracts of leaves of Dichrocephala integrifolia (D. integrifolia) against the eggs (fresh and embryonnated), the first and second larval stages of Heligmosomoides bakeri. In order to verify if this medicinal plant possesses active compounds capable of inhibiting the embryonation and hatching of eggs or to induce the mortality of larvae (L1 and L2).</p><p><b>METHODS</b>dried extracts were diluted in distilled FIV water to obtain five different concentrations: 625, 1,250, 2,500, 3,750 and 5,000 µg/mL. Fresh eggs obtained from artificially infected mice feces were exposed to these different concentrations for 48 h. Time of contact for embryonated eggs was 6 h while L1 and L2 larvae were exposed for 24 h. Distilled water (placebo) and 1.5% DMSO were used as negative controls.</p><p><b>RESULTS</b>Distilled water, and 1.5% DMSO had no effect on embryonation, hatching and larval survival. Aqueous extracts of D. integrifolia showed a weak activity against all stages of the parasite at all concentrations tested. On the contrary, the ethanolic extract of D. integrifolia inhibited the embryonation of 87.5% of fresh eggs, the hatching of 81.1% of embryonated eggs and induced the mortality of 98.1% and 98% of L1 and L2 larvae respectively at 5,000 µg/mL.</p><p><b>CONCLUSIONS</b>The results of the present study indicate that the ethanolic extracts of D. integrifolia contained compounds with ovicidal and larvicidal properties. In spite of these results, in vivo tests, studies on toxicity and mechanism of action of active compounds are also needed to validate the utilisation of this medicinal plant by population of Dschang-Cameroon to treat gastro-intestinal parasites.</p>

A comparative study of the ovicidal and larvicidal activities of aqueous and ethanolic extracts of pawpaw seeds Carica papaya (Caricaceae) on Heligmosomoides bakeri

OBJECTIVE@#To assess the ovicidal and larvicidal activities of aqueous and ethanolic extracts of pawpaw seeds Carica papaya (Caricaceae) on the eggs and first stage larvae (L(1)) of Heligmosomoides bakeri.@*METHODS@#Eggs of this parasite were obtained from experimentally infested mice (Mus musculus) and larvae were from eggs after incubation at 25∘C for about 72 hours. The eggs and larvae were exposed to ten different concentrations (0.125, 0.25, 0.375, 0.5, 0.75, 1.0, 1.25, 1.75, 2.25 and 2.75 mg/mL) of both aqueous and ethanolic extracts respectively for 72 hours. Distilled water and 0.05% ethanol used as placebo and negative control, respectively.@*RESULTS@#Placebo and negative control group all showed average 92% embryonnation, 98% egg hatching and 2% larval mortality, and did not affect development and larval survival. The extracts inhibited embryonic development, egg hatching and larval survival. In general, the ovicidal and larvicidal activities increased with increasing concentration of different extracts. The aqueous extract was found to be more potent on eggs than on larvae. At 2.75 mg/mL, only 8% of eggs embryonnated and 50% hatched to L(1) vs 57% embryonic development and 79% hatching occurred in the ethanolic extract. However, this later extract was more efficient in preventing larval development producing 96% mortality as against 68% with the aqueous extract.@*CONCLUSIONS@#These results shows the ovicidal and larvicidal properties of aqueous and ethanolic pawpaw seeds extracts.

Endoparasites of rodents and their zoonotic importance in Germi, Dashte-Mogan, Ardabil province, Iran

In order to verify the infectivity of rodents with endoparasites in Germi [Dashte-Mogan, Ardabil Province] the current study was undertaken. Using live traps, 177 rodents were trapped during 2005-2007. in field laboratory, all rodents were bled prior to autopsy, frozen at -20[degree sign] C, and shipped to the School of public Health, Tehran University of Medical Sciences, Iran. In parasitological laboratory, every rodent was dissected and its different organs were examined for the presence of any parasite. Blood thick and thin smears as well as impression smears of liver and spleen were stained with Geimsa and examined microscopically. Two species of rodents were trapped; Meriones persicus [90.4%] and Microtus socialis [9.6%]. The species of parasites found in M. persicus and their prevalences were as follows: Hymenolepis diminuta [38.8%], Hymenolepis nana [2.5%], Trichuris sp. [40.6], Mesocestoides larva [=tetraptrathyridium] [3.1%], Capillaria hepatica [6.9%], Moniliformis moniliformis [11.3%], Syphacia obvelata [2.5%], Taenia endothoracicus larva [0.6%], Physaloptera sp. [0.6%], Dentostomella translucida [0.6%, Heligmosomum mixtum [0.6%], Strobilocercus fasciolaris [0.6%], and Aspiculuris tetraptera [11.8%]. There were no statistical differences between male and female for infectivity with parasites in either M. persicus or M. socialis. No blood or tissue protozoan parasite was found in any of the rodents examined. Among different species identified, some had zoonotic importance. Therefore, the potential health hazard of these species needs to be considered to prevent infectivity of humans

Scanning electron microscopy of boreostrongylus seurati [nematoda: heligmosomidae] from the Egyptian desert gerbil gerbillus gerbillus with notes on its phylogeny

A heligmosomid nematode Boreostrongylus seurati, belonging to the subfamily Nippostrongylinae, was described and figured based on specimens collected from duodenum of Egyptian gerbil Gerbillus gerbillus [Olivier]. Both light and scanning electron microscopy were used to describe adult worms and their bursa and the synlophe. The ultrastructural morphology of some features of the worms was also described including mouth opening, cuticular surface, spicules, cephalic and bursal papillae