Search results
Results from the WOW.Com Content Network
Cestodes are parasites of vertebrates, with each species infecting a single definitive host or group of closely related host species. All but amphilinids and gyrocotylids (which burrow through the gut or body wall to reach the coelom [ 6 ] ) are intestinal, though some life cycle stages rest in muscle or other tissues.
Some of these fish parasites have heteroxenous life cycles (i.e. they have several hosts) among which sharks (certain cestodes) or molluscs (digeneans). The high biodiversity of coral reefs increases the complexity of the interactions between parasites and their various and numerous hosts. Numerical estimates of parasite biodiversity have shown ...
About 90% of nematodes reside in the top 15 cm (6") of soil. Nematodes do not decompose organic matter, but, instead, are parasitic and free-living organisms that feed on living material. Nematodes can effectively regulate bacterial population and community composition—they may eat up to 5,000 bacteria per minute.
Macroparasites [8] (worms or helminths) including nematodes such as parasitic roundworms and pinworms, tapeworms (cestodes), and flukes (trematodes, such as schistosomes). Diseases caused by helminths are sometimes termed infestations, but are sometimes called infections.
Macrocyclic lactones (such as ivermectin) are effective against adult and migrating larval stages of nematodes. Praziquantel is the drug of choice for schistosomiasis, taeniasis, and most types of food-borne trematodiases. Oxamniquine is also widely used in mass deworming programmes. Pyrantel is commonly used for veterinary nematodiasis.
Dec. 2—Proposed rules pushed by Gov. Kay Ivey that would place various restrictions on "inappropriate" books for children, including where public libraries shelve them, amount to censorship ...
Vertebrates, the best-studied group, are hosts to between 75,000 and 300,000 species of helminths and an uncounted number of parasitic microorganisms. On average, a mammal species hosts four species of nematode, two of trematodes, and two of cestodes. [85] Humans have 342 species of helminth parasites, and 70 species of protozoan parasites. [86]
Schistosomes, unlike other trematodes, are long and cylindrical worms and are sexually dimorphic. The male S. mansoni is approximately 1 cm long (0.6–1.1 cm) [5] and is 0.1 cm wide. It is white, and it has a funnel-shaped oral sucker at its anterior end followed by a second pediculated ventral sucker.