Cathaemasia hians infection in Black stork in Slovakia: morphological and histopathological study

Abstract

SummaryCathaemasia hians is an obligate trematode parasite of Black storks that are on the List of protected birds in Europe. In the present study, adult trematodes were isolated from the Black stork post mortem and morphological study revealed C. hians species. In total, 10 worms were found in the oesophagus and the ventriculus of the bird. Histopathological examination of the tissue samples of oesophagus, proventriculus and ventriculus was performed on paraffi n sections using a set of staining procedures. The sporadic lesions were seen in the tela submucosa of oesophagus containing connective tissue mast cells, eosinophils and heterophils and some foci were surrounded by the fi brous tissue. In addition, a few infl ammatory nodules had larval-like material inside, probably being of the same species. There were no visible morphological alterations in the epithelial layer of lamina propria mucosae of proventriculus, rich in goblet cells as well as in the tela submucosa. Majority of trematodes were localized in the ventriculus, where the lamina propria mucosae was damaged or disrupted sporadically. In these sites, in the tela submucosa, a various food-originated inorganic/organic material and eggs of C. hians were deposited, stimulating a weak infl ammatory response. Nodules containing larvae were not observed in any of ventriculus tissue layers. This study demonstrated, for the fi rst time, infection with adults of C. hians trematode in the Black stork nesting in Slovakia. The presence of larvae and eggs in the tissues of the upper gastrointestinal tract of bird was associated with mild infl ammatory response but feeding behaviour of adult worms in the ventriculus probably contributed to the enhanced susceptibility of the lamina propria mucosae to mechanical damage by inorganic material. Although larval stages have not yet been documented in the intermediate hosts in Slovakia, our report indicates that the life cycle of C. hians might occur in Central Europe.

First report of one ecto- and two endoparasite species of the black stork (Ciconia nigra) in Portugal

“…Scientific studies regarding these birds are difficult to accomplish since they are hard to access and protected by European laws. Thus, living animals can only be found after sustaining serious injuries [9,12,18], like in the present study.…”

“…Massive infections by this parasite can cause serious health problems when combined with cachexia or lower immunity of the hosts [9,13]. This is also the first reference for this parasite in a black stork captured in Portugal.…”

“…Information concerning parasitological fauna found in C. nigra is available in only a few published works, but data are still scarce and more studies are necessary in this area [9][10][11][12][13][14]. The main reason for this lack is related to the black stork's habitat, since these birds breed in dense wood areas where precise nesting surveys are difficult to carry out.…”

“…The main reason for this lack is related to the black stork's habitat, since these birds breed in dense wood areas where precise nesting surveys are difficult to carry out. Moreover, because they are included in the list of protected animals in Europe [9], human contact with them should be avoided in order to not disturb them in their natural habitat.…”

Presence of one ecto- and two endoparasite species of the black stork (Ciconia nigra) in Portugal

“…The main reason for this lack of information is related to the black stork’s habitat, since these birds breed in dense wood areas where precise nesting surveys are difficult to carry out. Moreover, because they are included in the list of protected animals in Europe [9] , human contact should be avoided in order to not disturb them in their natural habitat.…”