PDFDOI: https://doi.org/10.2478/v10058-009-0019-5
The penetration mechanism of Sphaerirostris picae cystacanths in intestinal wall of the paratenic host Lacerta agilis and characteristic features of inflammatory changes in host intestinal wall are examined. Inflammatory reaction is characterized by predomination of eosinophiles and comparatively small amount of neutrophiles. The reaction is much more pronounced when cystacanth is placed in parallel to the wall of intestine. Extensive edema, plethora, stases in vessels, and slight hemorrhages are observed in submucous membrane. Inflammatory infiltration is less pronounced in case of perpendicular orientation of the proboscis. The secretory glands in cystacanths were not found, secretion on the tegumental surface was not seen, as well as no morphological effect of lytic enzymes on host tissues. The penetration of host intestinal wall is shown to be mechanic, advancement of the cystacanth through the wall of intestine is due to alterations of partial evagination and invagination of the presoma in combination with contractions of the metasoma.