Histopathological changes in the stomach wall of the European grayling Thymallus thymallus associated with severe infection by the nematode Cystidicoloides ephemeridarum

Infection status of masu salmon Oncorhynchus masou by the parasite Salmonema cf. ephemeridarum (Nematoda, Cystidicolidae)

“…A few studies have reported the influence of freshwater nematodes on salmonids (Frantová & Moravec, 2003; Iaria et al, 2021; Kulikowski et al, 2017). These studies showed histopathological effects of nematodes, such as focal disruption of the gastric laminae mucosae of the hosts, which might decrease the digestive function of the hosts.…”

“…One of the reasons for the negative effect of infection intensity on the condition factor of fish is that the nematodes sometimes invade the mucous lining of the stomach, thereby reducing its digestive function. Several studies have mentioned the resulting histopathological changes, including focal atrophy or disruption of gastric laminae mucosae at the attachment site of the nematodes (Frantová & Moravec, 2003; Iaria et al, 2021; Kulikowski et al, 2017). In addition, histopathological samples taken from the gastric wall of experimentally infected O. masou had these same features (see Appendix B).…”

“…Kulikowski et al, 2017). These studies showed histopathological effects of nematodes, such as focal disruption of the gastric laminae mucosae of the hosts, which might decrease the digestive function of the hosts.…”