Larvae development

Fig. 5.5. Best-fit regression lines of A proportion (the difference in the proportion of larvae developing at 25 and 19°C) into free-living males ( ), free-living females ( ) or iL3s that developed by the homogonic route of development (a) through an infection. Error bars are 95% confidence intervals. Some error bars are smaller than the symbol.

Riddle, D.L. and Albert, P.S. (1997) Genetic and environmental regulation of dauer larva development. In Riddle, D.L., Blumenthal, T., Meyer, B.J. and Priess, J.R. (eds) C. elegans II. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York, pp. 739-768. 

Early life-stages. Hatching and larvae development as endpoints of toxicity... 

Adult females lay eggs in other inseets and the larvae develop as parasites, killing the host. A number of them ean be purehased as biologieal eontrol agents see p.97). 

Tapeworm. A parasitic intestinal cestode worm having a flattened, band-like form. The eggs of tapeworms are ingested by the intermediate host, they produce the larval stage in tissues. When the flesh of intermediate host is eaten, the larvae develop within the alimentary canal of the definitive host into adult tapeworms. 

Hopkins, W. A., Congdon, J. D. Ray, J. K. 2000. Incidence and impact of axial malformations in bullfrog larvae developing in sites impacted by coal combustion byproducts. Environmental Toxicology and Chemistry, 19, 862-868. 

Among the two genotoxicity tests, the Mutatox is a commercial test using a bacterial strain and is no more difficult to perform than the well known Microtox test. The test on induction of micronuclei in erythrocytes of Xenopus laevis larvae developed by van Hummelen et al. (1989) requires specialized skills and training and is routinely performed only in a few laboratories. However, this test is currently being standardized by ISO (International Standardization Organisation). 

Mosquitoes have long been identified as pests and vectors of disease. It has also been known for some time that tires have the potential to serve as ideal breeding grounds for mosquitoes, especially when tires occur in large numbers in stockpiles. Because of the shape and impermeability of tires, they may hold water for long periods of time providing sites for mosquito larvae development. 

Most work has centred on cyclophyllidean species whose larvae develop in mammals. Few studies have been made on the other cestode orders, such as the Pseudophyllidea whose larvae develop in lower vertebrates, especially fish, amphibia and reptilia. Apart from the H. nana/rodent system, discussed earlier, the most studied species have been those which are either readily maintained in laboratory animals or are of medical, veterinary or economic importance, i.e. Echinococcus granulosus, E. multilocularis, Mesocestoides corti, Taenia crassiceps, T. hydatigena, T. multiceps, T. ovis, T. saginata and T. solium. The account given here has been restricted largely to these species. 

Pupa— An insect in the nonfeeding stage during which the larva develops into the adult. 

Insects that parasitize other insects are called parasiloids. They lay eggs singly or in groups near, on, or inside the bodies of other insects. The parasitoid larvae develop as internal parasites. Parasitoids eventually kill the host, then pupate inside or crawl outside and pupate near the dead husk. 

Beneficial Effect Larvae develop as parasites of caterpillars, sawfly and beetle larvae, and other insects. Females also kill hosts by stinging them and feeding on body fluids. Ichneumon wasps are extremely important... 

Life Cycie Females lay eggs inside host eggs or larvae wasp larvae develop inside hosts, eventually killing hosts and pupating in or on them. Many species overwinter as mature larvae in cocoons in some species adult females overwinter. One to 3 generations per year usual some with up to 10 generations. 

Life Cycle Females lay single eggs in soil burrows larvae prey on insects that fall into burrows larvae develop for several years before adulthood. One generation takes 2-3 years. 

Life Cycie Overwintering eggs hatch in spring larvae develop for 4-6 weeks, then pupate in cocoons on nearby trees adults emerge in 2 weeks, mate, and lay eggs on old cocoons. Up to 3 generations per year. 

After reaching the intestine of human, the eggs liberate larvae which penetrate the bowel wall and enter the portal blood system from where they are carried to the liver, lungs and different parts of the body. The larva seldom develops into the adult in the human intestine as man is not its natural host. In cats and dogs, the larvae develop into male and female adults. 

Considering, that in recent years the salinity of Aral waters has steadily grown, and in October 2005 B. gr. noctivaga larvae developed in a top layer of the bottom surface at a salinity of up to 134 ppt in the northern part of the Eastern basin, it is possible to speak about their high resistance to this factor. Also we noted that in the... 

Buprofezin is a specific poison for Homoptera, but the mode of action is not known. It is included in this chapter because it probably interferes with molting or chitin synthesis in some way It inhibits embryogenesis and progeny formation of some insects at very low concentrations (see Ishaaya, 1992). Cyromazil was first marketed in 1980 and is an insect growth regulator. Insect larvae, particularly fly larvae, develop cuticular lesions before they eventually die. 

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