Incidence and histopathology of encysted progenetic metacercaria of Clinostomum complanatum(Digenea:Clinostomidae) in Channa punctatus and its development in experimental host

• Published in: Asian Pacific journal of tropical biomedicine 2012-06, Vol.2 (6), p.421-426
• Main Authors: Shareef, PA Ahammed, Abidi, SMA
• Format: Article
• Language: English
• Subjects: adult; Animals; Channa; Channa punctatus; Chickens; Chordata - parasitology; Clinostomum; Clinostomum complanatum; complanatum; Disease Models, Animal; Encysted; Encysted progenetic metacercaria; Experimental; Experimental infection; Fish Diseases - epidemiology; Fish Diseases - parasitology; Fish Diseases - pathology; Histocytochemistry; Histopathology; Host-parasite; Host-parasite interaction; Incidence; India; infection; interaction; metacercaria; Metacercariae - growth & development; Metacercariae - isolation & purification; Metacercarial; Metacercarial transformation; Microscopy; Original; Ovigerous; Ovigerous adult worm; Parasitology; progenetic; punctatus; transformation; Trematoda - growth & development; Trematoda - isolation & purification; Trematode Infections - epidemiology; Trematode Infections - parasitology; Trematode Infections - pathology; Trematode Infections - veterinary; worm
• ISSN: 2221-1691; 2588-9222
• DOI: 10.1016/S2221-1691(12)60068-9

Objective:To study the incidence of encysted progenetic metacercariae of Clinostomum complanatum(C. complanatum) in Channa punctatus(C. punctatus), associated histopathology and the experimental infection to laboratory chicken to obtain ovigerous adult worms.Methods:Live C. punctatus were brought from local fish market of Aligarh, India, dissected and examined on a monthly basis for the presence of C. complanatumcysts. For histochemistry, infected tissue sections with attached cysts were processed for haematoxylene and eosin staining. Cysts were aseptically fed to 4 day old leghorn chicken to obtain adult worms. Mechanically excysted metacercaria and the ovigerous adult worms were stained in carmine to prepare permanent slides.Results:One year survey for the infection of encysted progenetic metacercaria of C.complanatuminC. punctatusrevealed the prevalence, intensity and abundance of 24.7%, 2.27and 0.608, respectively. Histopathology showed heavy infiltration of immune cells at the site of cyst attachment and some tissue damage was also evident. Following feeding to experimental chicken, about 41.07% of the encysted metacercariae were able to excyst and migrate back to bucco-pharyngeal region where they tenaciously attached and fed on blood, and transformed into ovigerous adult worms from 62 hours onwards of post infection.Conclusions:The parasite is potentially pathogenic to the host, and the availability of a suitable intermediate host can be a contributing factor for the occurrence of C. complanatummetacercaria either in the excysted or encysted form, indicating loose host specificity and zoonotic potential.