Differential survival of 3rd stage larvae of Contracaecum rudolphii type B infecting common bream (Abramis brama) and common carp (Cyprinus carpio)

Abstract

The main fish host reaction to an infection with third stage anisakid nematode larvae is a response in which host immune cells (macrophages, granulocytes, lymphocytes) in affected internal organs initially are attracted to the parasite whereafter fibroblasts may enclose the parasite forming granuloma. Generally, the reaction is non-lethal to the parasite which may survive for years in the fish host retaining infectivity to the final host. This may also apply for the anisakid nematode Contracaecum rudolphii (having the adult stage in cormorants, using copepods as first intermediate/paratenic host and zooplankton feeding fish as paratenic hosts). The present study has shown that most Contracaecum rudolphii larvae survive in bream (Abramis brama) (from Lake Balaton, Hungary) whereas the majority of the nematode larvae die in Cyprinus carpio (from Lake Hévíz, directly connected to Lake Balaton). Both cyprinid host species interacted with the nematode larvae through establishing a marked cellular encapsulation around them but with different effects. The differential survival in common carp and bream may theoretically be explained by ecological factors, such as the environmental temperature which either directly or indirectly affect the development of nematode larvae, and/or intrinsic host factors, such as differential immune responses and host genetics.

Molecular characterization of zoonotic anisakid Contracaecum spp. larvae in some fish species from Lake Nasser, Egypt

“…Different cross sections of 3rd larval stages of Contracaecum spp. were detected, surrounded by fibrous capsules and inflammatory reactions, which was consistent with the findings of Molnár et al (2019), who discovered that 3rd stage larvae of C. rudolphii infecting the intestinal wall of Abramis brama and Cyprinus carpio encapsulate with fibroblasts and are surrounded by host immune cells forming granuloma. Thus, the pathogenicity of Contracaecum third larval stage is dependent on the infected fish species, the size and number of parasitic nematodes, and the site of infection, which is consistent with the findings of Molnar et al (2006).…”

Morphology and Molecular Studies of Contracaecum Larvae (Nematoda: Anisakidae) in Some Fish species from Sulaimani Province, Kurdistan Region, Iraq

“…(1). Furthermore, there are few publications on the specific identification of Contracaecum larva in fishes from the world (Szostakowska & Fagerholm, 2007;Shamsi & Aghazadeh-Meshgi, 2011;Shamsi et al, 2017;Molnár et al, 2019;Pekmezci & Yardimci, 2019). The present investigation identifies the third larval stage of Contracaecum by using molecular genetic approach.…”

Ultramorphology and molecular studies of Contracaecum larvae (Nematoda: Anisakidae) collected in five Cyprinid fish species from Sulaimani Province, Kurdistan Region-Iraq

“…2018 ; Malviya et al ., 2018 ). There are a few publications on the specific identification of the larval stages of Contracaecum in fishes from the world ( Szostakowska & Fagerholm, 2007 ; Shamsi & Aghazadeh-Meshgi, 2011 ; Shamsi et al ., 2017 ; Molnár et al ., 2019 ; Pekmezci & Yardimci, 2019 ).…”