Prevalence and intensity of Sarcocystis spp. infection in animals slaughtered for food in Lithuania

Abstract

The exact prevalence of Sarcocystis spp. infection in animals slaughtered for food is unknown in Lithuania. Therefore, the present study was initiated to evaluate Sarcocystis spp. infection in the carcasses of cattle (n = 206), sheep (n = 61), pigs (n = 73) and horses (n = 72) raised in Lithuania for food. The prevalence and intensity of Sarcocystis spp. infection were assessed under light microscopy by analysing 1 g of stained and squashed muscle samples. All the investigated muscle types (oesophagus, diaphragm, heart, neck, jaw, back, leg and tongue) were found to have been infected with microcysts rather than with macrocysts. A high prevalence of infection was established in cattle (44.9–98.1%) and sheep (100%), whereas the prevalence of this infection in pigs (30.1–50.0%) and horses (34.7–63.9%) was considered to be moderate. Significant differences in the infection prevalence were detected in the majority of muscle groups of cattle and in some muscle groups of pigs and horses. Similarly, significant differences in the median (Md) intensity of infection were observed in the majority of the muscle groups of cattle (Md = 4–29) and sheep (Md = 21–73) and only in some muscle groups of pigs (Md = 4.5–16) and horses (Md = 1–3). Cases of intense infection (> 40 cysts in a sample) were relatively often detected in sheep (44.9%) and cattle (19.1%), and rarely in pigs (3.7%). Hence, based on the varying rates of infection in the examined samples, the infection was identified as being intense in sheep and cattle, moderate in pigs and low in horses.