Comparación de tres técnicas de concentración de heces para recuperar ooquistes de Cryptosporidium

cryptosporidium is a parasite which causes cryptosporidiosis. its infectious stage, the oocyst, is eliminated with the host feces, calves being the main source of human infection. the aim of the present work was to compare three methods of feces concentration to recover cryptosporidium oocysts. a total of 166 calves were studied. an only sample of fresh feces was analyzed using the following methods: modified telemann, water ether, and tris tween 80. the identification of oocysts was carried out by modified staining kinyoun technique. the number of concentrated oocysts per technique was quantified in 20 fields at 1000x. from a total of 166 analyzed samples, 22 were cryptosporidium positive. the average number of recovered oocysts per technique was: modified telemann (124.2±159.5), water ether (153.0±156.3), tris tween 80 (92.2 ± 98.3). anova demonstrated that there are no significant differences between these methods. according to the results obtained, the three techniques may be used to concentrate cryptosporidium oocysts. even if there are no differences in sensibility and specificity between these methods, the water ether technique proved to be simple, low-cost, and effective to recover oocysts, particularly if the oocysts condition is to be kept.