Possible species differences between Sarcocystis from mule deer and cattle

Area of Science:

• Veterinary Parasitology
• Protozoology
• Wildlife Disease

Background:

• Sarcocystis are protozoan parasites with complex life cycles involving intermediate hosts (like cattle and deer) and definitive hosts (canids).
• Understanding Sarcocystis species diversity is crucial for animal health and food safety.

Purpose of the Study:

• To investigate the potential species distinctiveness of Sarcocystis parasites found in bovine (Bos taurus) and mule deer (Odocoileus hemionus hemionus).
• To determine if different Sarcocystis isolates from these ruminants utilize canids as definitive hosts.

Main Methods:

• Experimental infection of a coccidia-free domestic dog (Canis familiaris) and a captive coyote (Canis latrans) with Sarcocystis-infected bovine and mule deer meat.
• Monitoring canine hosts for the presence and morphology of sporocysts shed in feces.

Main Results:

• Both canine hosts successfully shed Sarcocystis sporocysts 10-15 days post-ingestion of infected meat.
• A statistically significant difference in sporocyst size was observed between isolates originating from bovine and mule deer.

Conclusions:

• The findings suggest that Sarcocystis from cattle and mule deer are likely distinct species.
• The life cycle appears host-specific, requiring both a ruminant intermediate host and a canid definitive host for each Sarcocystis type.