The occurrence of Sarcocystis spp. in the myocardium of alpacas (Vicugna pacos) with associated risk factors in the Peruvian Andes

Abstract

Sarcocystis is a threat to food security in the Peruvian Andes. The Sarcocystis species that forms microcysts in the myocardium of alpacas is S. masoni n. sp. (known as "S. lamacanis"). There is a lack of current studies estimating the prevalence of this parasite in alpacas, although this information is crucial for the control and prevention of sarcocystosis. The aim of this study was to determine the frequency and cyst density of Sarcocystis masoni n. sp. in the myocardium of alpacas in Huancavelica, a province of the Andean region of Peru. Myocardial samples for histological analysis were taken from 104 alpacas slaughtered in an o cial abattoir in the area. All alpacas (100%) presented this parasite. About 44% (95% CI: 34.5-53.5%), presented from 31 to 45 microcysts per mm2 of myocardial histological slide (cyst density). Cyst density was signi cantly higher (p<0.05) as the age of the animals increased. In addition, cyst density was signi cantly higher (p<0.05) in 4-and 5-years-old males compared to females of the same age. These results con rm that myocardial sarcocystosis is highly endemic in alpacas in Peru.

Sarcocystis spp. of New and Old World Camelids: Ancient Origin, Present Challenges

“…Microscopic sarcocysts, referred to as Sarcocystis sp., S. lamacanis or, more recently, S. masoni , were reported in the cardiac muscle of llamas and guanacos from Argentina, alpacas from Peru, and alpacas bred in the extra-Andean countries China, Iran, and Australia [ 17 , 33 , 46 , 62 , 63 , 64 , 65 , 66 ]. Microcysts were, in some cases, also observed in other body locations in addition to the myocardium, such as liver, kidney, spleen, lung, tongue, and skeletal muscles [ 17 , 33 , 62 , 63 ].…”

“…Available studies on the prevalence of camelid sarcocystosis show high-to-very-high values both in SACs and OWCs [ 38 , 50 , 51 , 52 , 53 , 56 , 57 , 66 , 68 ]. Representative examples of these reports are presented in Table S1 .…”