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AutoresPamela Muñoz A Rubén Mercado P Gabriela Morales T Viviana Bravo O Eduardo Raffo C
Objective. To determine the Cryptosporidium spp. infection frequency by using Ziehl-Neelsen and Auramine stains on samples obtained from diarrheic calves from milking farms of the Valdivia province. To compare both diagnostic tests and to determine the geospatial distribution of the infections caused by this protozoan. Materials and methods. 221 fecal samples of diarrheic calves of 24 milking farms of the Valdivia province were studied. The processing and analysis of the samples was done by Ziehl-Neelsen (ZN) and Auramine (AU) staining techniques, and the results were compared by McNemar statistical test and the concordance level was determined by kappa index. A map was also generated to determine the geospatial distribution of Cryptosporidium infections. Results. 57.9% of all the animals tested were classified as positive with the ZN stain test, while 55.6% of all the animals turned out positive for the AU stain test. The McNemar test showed no significant difference between both diagnostic techniques (p>0.05), while the kappa index showed proper concordance between tests (κ=0.73). 100% of the farms studied showed protozoan presence demonstrating the broad distribution of the parasite, however, and considering the previous factor, it was not possible to determine geospatial associations for the parasite distribution. Conclusions. The infection frequency of Cryptosporidium is higher than 50% in the milking farms studied from the Valdivia province. No difference between the Ziehl-Neelsen and Auramine staining techniques was demonstrated showing very consistent results. It was possible to detect that the number of farms infected correspond to 100% of the farms analyzed.
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2. Thompson R, Olson M, Zhu G, Enomoto S, Abrahamsen M, Hijjawi N. Cryptosporidium and Cryptosporidiosis. Adv Parasitol 2005; 59:78-139. http://dx.doi.org/10.1016/s0065-308x(05)59002-x
3. Chalmers R, Campbell B, Crouch N, Davles A. Clinical laboratory practices for detection and reporting of Cryptosporidium in community cases of diarrhoea in the United Kingdom. Euro Surveill 2008; 15:1-5.
4. Romero R, Pedrozo R, Vera E. La cryptosporidiosis en los terneros recién nacidos. Su etiología, patogenia, síntomas, tratamiento y profilaxis. Revista de ciencia y tecnología 2001; 3:99-108.
5. Díaz-Lee A, Mercado R, Onuoha E, Ozaki L, Mu-oz P, Mu-oz V, Martínez F, Fredes F. Cryptosporidium parvum in diarrheic calves detected by microscopy and identified by immunochromatographic and molecular methods. Vet Parasitol 2010; 176:139-144. http://dx.doi.org/10.1016/j.vetpar.2010.11.001
6. Mu-oz P, Fredes F, Díaz-Lee A, Mercado R, Ozaki L. Detección de Cryptosporidium spp. en terneras de lecherías de la Región Metropolitana mediante Ziehl Neelsen y confirmada por inmunocromatografía y ensayo molecular. Arch Med Vet 2011; 43:111-116. http://dx.doi.org/10.4067/S0301-732X2011000200003
7. Fayer R, Xiao L. Cryptosporidium and Cryptosporidiosis. New York, USA. Ed CRC Press, 2007.
8. De Quadros R, Marques S, Amendoeira C, De Souza L, Amendoeira P, Comparin C. Detection of Cryptosporidium oocysts by Auramine and Ziehl Neelsen staining methods. Parasitol Latinoam 2006; 61:117-120. http://dx.doi.org/10.4067/S0717-77122006000200003
9. Fredes F, Raffo E, Mu-oz P. First report of Cryptosporidium spp. oocysts in stool of Adélie penguin from the Antarctic using acid-fast stain. Antarct Sci 2007; 19(4):437-438. http://dx.doi.org/10.1017/S0954102007000429
10. Dohoo I, Martin W, Stryhn H. Veterinary Epidemiologic Research. Edward Island, Canadá. AVC Inc. 2003.
11. Hänscheid T, E Valadas. Diagnosis of Cryptosporidiosis using PCR or auramine O with LED fluorescent microscopy: Wich end of the stick? Acta Trop 2009; 109:247-248. http://dx.doi.org/10.1016/j.actatropica.2008.08.008
12. Brook E, Christley R, French N, Hart C. Detection of Cryptosporidium oocyst in fresh and frozen cattle faeces: comparision of three methods. Let Appl Microbiol 2008; 46:26-31.