The pathology of Myxidium giardi Cépède, 1906 infections in wild and cultured eels, Anguilla anguilla L.

• Published in: Journal of Fish Diseases
• Main Author: COPLAND, J. W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1983
• Subjects: Anguilla anguilla
• Online Access: http://dx.doi.org/10.1111/j.1365-2761.1983.tb00099.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-2761.1983.tb00099.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2761.1983.tb00099.x

Abstract. The histopathology of Myxidium giardi infections in wild and cultured elvers, fingerlings and adult eels is described. The lesions in the target organs of the kidney and gills were minimal. Marked granulomatous changes were evident in the spleen, peritoneal fat and, to a lesser extent, the liver and gas gland. The granulomatous reaction consisted of a mononuclear infiltration into the spore mass and proliferative fibrosis of the surrounding connective tissue, Histological evidence of an immunological response is described. The types of M. giardi cysts are described‐a primary interstitial cyst of the kidney and gill, a secondary cyst of the gills and a glomerular spore mass. Primary interstitial cysts in the kidney were observed to rupture and formed spore masses in the interstitial tissue. Evidence of vascular spread and the presence of spore emboli is presented. It is suggested that primary multiplication occurs in the primary interstitial cyst of the kidney and gills, and secondary multiplication in the secondary gill cyst and glomerular spore mass from which mature spores are released to the environment.