Experimental Infection of Swine by Isospora suis Biester 1934 for Species Confirmation

Abstract

Key words: Isospora suis -life cycle -neonatal isosporosis -pathogenicityIsospora suis has been considered an important enteroparasite of piglets which causes coccidiosis in neonatal swine (Ruzicka & Andrews 1983). Yellowish-pasty diarrhoea is the most characteristic clinical sign of the disease which is more prevalent in piglets between 5 to 21 days old. It does not respond to any antibiotic treatment (Lindsay 1989) but experiments with an anticoccidial drug toltrazuril have been successfully used experimentally (Mundt 1994) as well as in some swine farms (Kondela et al. 1991, ByeungGie 1995 pressures of oocysts by the time of faecal examination. Life cycle and oocyst structure of Sarcocystis species were unknown at the time of their articles publication.In the present study an experimental infection of thin wall type oocysts was performed in piglets for the confirmation of I. suis species characterized by clinical signs, possible small intestine tissue lesions, oocyst structure and life cycle observations. MATERIALS AND METHODSThin wall oocysts were isolated from four faecal samples collected in swine farms and cultivated according to the method described by Long et al. (1976) with some modifications. Faecal samples were filtered through a metalic sieve of 50 meshes, centrifuged in 800 g for 5 min to obtain the pellet and cultivated in 2% potassium dichromate solution with oxygen aeration at room temperature of about 25 o C during at least 72 hr. This type of oocysts was inoculated in four-five-day-old pigs free of contamination: pig 1 received 6.6 x 10 4 sporulated oocysts, pig 2 received 10 3 oocysts, and pigs 3 and 4 received 4 x 10 4 oocysts.They were kept in individual metal cages and fed with cow milk. Daily observations of pigs for dehydration level, general conditions, faecal consistency and oocyst production were performed until the 21st day after inoculation. MacMaster and Sheather' s methods were used for oocyst identifi-

Bumped kinase inhibitor 1369 is effective against Cystoisospora suis in vivo and in vitro

“…Isospora suis ) is one of the leading causes of diarrheal disease in suckling piglets. The disease is usually non-fatal but of high morbidity in affected litters (Lindsay et al, 1985; Roepstorff et al, 1998; Sayd and Kawazoe, 1998). Cystoisosporosis is characterized by watery-to-pasty non-hemorrhagic diarrhea, impaired weight gain and reduced and uneven weaning weights in piglets, and consequently imposes significant economic losses on the pig farming industry (Mundt et al, 2005, 2007; Shrestha et al, 2015).…”

Infection dynamics of Cystoisospora suis (Isospora suis) on a pilot swine farm in Carabobo State, Venezuela

“…Los resultados obtenidos coinciden con lo señalado por otros autores, quienes determinaron mayores valores de prevalencia en las dos primeras semanas de vida, y podría deberse a la falta de un adecuado programa de profilaxis y control en la granja, lo que trae consigo mayor presión de infección en esta edad (9,12) ; sin embargo, en otros estudios se determinó mayores tasas de prevalencia en camadas de 3 y 4 semanas de vida (5,7,14) . Dado que los lechones nacen con un sistema inmune inmaduro, la transferencia calostral de anticuerpos y células inmunes parece ser un factor esencial para controlar las infecciones a esa edad.…”

“…En Venezuela, se determinó que la prevalencia de C. suis en lechones y cerdos de 0 a 13 semanas de edad fue 21.8 y 26 %, respectivamente (10) , mientras que se encontró 75 % de prevalencia en granjas ubicadas en el estado Carabobo (11) . Con respecto a la edad, se ha determinado mayor prevalencia en camadas con dos semanas de vida (12) , mientras que otros autores señalan mayor prevalencia en camadas de tres y cuatro semanas de edad (13) . Referente a la época del año, algunos autores (5,14) no señalaron efecto estadísticamente significativo sobre la presencia de C. suis en lechones; sin embargo, Meyer et al (6) demostraron en granjas de Alemania mayor incidencia de diarrea por C. suis en verano y otoño (66.3 y 61 %, respectivamente).…”