Prevalence of Sarcocystis spp. in water buffaloes in Vietnam.

Muscles from heart, tongue, oesophagus, neck and abdomen from 502 adult water buffaloes (Bubalus bubalis) slaughtered in Ho Chi Minh City, Vietnam, between 1996 and 1997 were examined for Sarcocystis cysts by a combination of ocular and histological examination. Sarcocysts were present in 396 (79%) of the animals and the prevalence increased with age from a 57% infection rate among 2-3 year old animals to 93% among 6-7 year olds. The prevalence was higher in animals originating from the northern part (89%) than in those from the southern part (69%) of the country. Four species of Sarcocystis were identified. S. levinei (74%) was the most common species found, followed by S. fusiformis (41%), S. buffalonis (33%) and S. dubeyi (12%). All four species were present in 8% of the infected animals. The most common site for sarcocyst location was oesophagus, followed by cervical muscles, tongue and heart.