Submitted to: American Society of Parasitology
Publication Type: Abstract Only
Publication Acceptance Date: June 30, 2001
Publication Date: June 30, 2001
Citation: Li, X., Fayer, R., Trout, J.M., Lunney, J.K. 2001. Infectivity of Microsporidia for Food Animals: Livestock and Poultry. [Meeting Abstract].American Society of Parasitology.
Three species of Encephalitozoon were grown in cell culture and spores were harvested for infectivity studies. E. cuniculi (Ec) and E. intestinalis (Ei) were grown in MDBK cells;E. hellem (Eh) was grown in WI-38 human lung fibroblasts. For each species, 1 x 106spores were inoculated orally into each test animal. Infectivity was tested in 8-month-old NIH miniature pigs, ,neonatal Holstein calves, and 1-week-old turkey poults.Twelve pigs were divided into 4 groups of 3 each, one group received Ec, another received Ei, a third group received Eh, and the fourth gruop was an uninoculated control. Eight calves were divided into groups, 4 calves received Ei, 2 received Ec, 1 received Eh, and 1 served as a control. Ten turkeys poults were divided into 2 groups of 5 each. One group received Eh, and the other group served as a control. Feces were collected daily for 28 days ffrom pigs and calves and for 7 days from turkeys. Fecal smears were prepared, stained with Calcofluor White, and examined for the presence of spores by fluorescence microscopy. At the end of the fecal collection periods, animals were euthanized. Tissues were collected, fixed in 10% neutral buffered formalin, paraffin embedded, sectioned and stained with the hot gram chromotrope technique. Stained slides were examined by brightfield microscopy for the presence of intracellular stages. Neither spores nor intracellar stages were observed in fecal smears or tissue sections of any of the test or control animals. These results suggest that exposure by oral inoculation of Encephalitozoon spores did not produce infections in pigs, calves or turkeys.