Prevalence of Sarcocystis spp in Argentinean cattle

MORÉ, G.; JURADO, S.; TEITELBAUM, D.; ABRAHAMOVICH, P.; BACIGALUPE D.; RAMBEAUD M.; VENTURINI M.C.; VENTURINI L.

Calgary

Congreso; The 22nd International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP 2009); 2009

Sarcocystis infections affect cattle worldwide and are frequently asymptomatic. Bovines are intermediate hosts for S. cruzi, S. hirsuta and S. hominis, which have canids, felids and primates as respective definitive hosts. The objective of this study was to determine prevalence of different Sarcocystis spp in cattle from Argentina. Blood, heart and loin samples (n=300) were collected at slaughter from 142 cows, 73 steers, 72 heifers and 13 bulls from 8 provinces in Argentina. Ten grams of muscle were homogenized in a meat grinder with PBS, centrifuged, filtered and observed in a stereomicroscope. Sarcocysts were classified as thin wall (S. cruzi) or thick wall cysts (S. hirsuta or S. hominis), and a subset was further characterized by transmission electron microscopy (TEM). Antibody detection was performed by immunofluorescence antibody test (IFAT) using S. cruzi bradyzoites as antigen and serum samples diluted at 1/25, 1/200 and 1/800. Ninety nine point three percent of heart samples had S. cruzi and no thick wall sarcocysts; 72% of loin samples had S. cruzi sarcocysts, 27% had thick wall sarcocysts, and 25.6% had both kinds of sarcocyst. Thick wall sarcocysts were detected in samples from 7 provinces. Thick wall sarcocysts were identified as S. hominis and S. hirsuta by TEM. IFAT titer distribution was as follows: 23.7% of animals had a titer of 25, 55% had a titer of 200, 21% had a titer of 800 and 0.3% were negative. This is the first report of S. hominis and S. hirsuta in Argentina.