Contribuição para o estudo do Ascaris lumbricoides em laboratório

Abstract

With the purpose of standardising techniques for the laboratory study of Ascaris lumbricoides, faeces were collected from children parasitised by A. lumbricoides, during a 24 hour period. The fecal samples were sieved and resuspended several times in water. The sediment containing the eggs was cultivated in H2SO4 0.1N in tissue culture flasks, at 28 degrees C. The culture of embryonated eggs was determined every ten days starting from the 20th day of culture achieving around 98.0% embryogeny on the 80th day of culture. The best day to recover larvae from mice was determined by infecting 9 groups of 5 mice per os with 200 embryonated eggs/mouse. Each mouse was sacrificed by cervical rupture starting on the 4 day up to the 12 day of infection. On the 8 day after the infection 0.45% of the larvae were recovered from the lungs. The inoculum determination was performed by using 5 groups of 10 infected mice with 200, 400, 800, 1,600 and 3,200 embryo eggs/mouse. The best age for recovery of infection was achieved by using 4 groups animals, with 5 mice/group, with age varying from 20 to 50 days and an inoculum of 3,200 eggs. The best recovery (1.9% was obtained from the group of 20 days of age.

Ascaris lumbricoidesandAscaris suumvary in their larval burden in a mouse model

“…In a mouse model of ascariasis, A. suum has tended to be the species of choice, with A. lumbricoides much less commonly used (Stewart, 1917, 1918; Sprent, 1952b; Bhowmick, 1964; Cho, 1967; Buske & Engelbrecht, 1968; Kumar & Singh, 1968; Maung, 1978; Massara et al ., 1990, 1991; Peng et al ., 2012; Gazzinelli-Guimarães et al ., 2013). To the best of our knowledge, no previous study has provided a detailed comparison of the larval burden of the two ascarid species derived from the two most important organs in early migration, the liver and the lungs.…”