Preliminary Investigations of Disease-Causing Organisms in the White-Clawed Crayfish Austropotamobius Pallipes Complex From Streams of Northern Italy

Abstract

A total of 99 live and 3 dead white-clawed crayfish Austropotamobius pallipes complex were collected during the summer and autumn of 2003 from one creek in Emilia Romagna region and four watercourses in Friuli Venezia Giulia region (Northern Italy) for experimental breeding and health status monitoring. Fifty-one animals from the Bidente River were maintained in tanks for breeding, and restocking, while another 30 specimens (27 living and 3 dead) were examined in the laboratory to evaluate their health status. Parasitological surveys were carried out on gills; mycological examinations on the exoskeleton (the walking legs and the abdomen); bacteriological examinations of inoculations from the haemolymph, and histopathological analysis on full transverse and sagittal sections of cephalothorax and abdomen.In the branchial-chambers, the gill filaments and the exoskeleton were observed for ectocommensal peritrich protozoans Epystilis spp. and Cothurnia sieboldii. In crayfish sampled from five streams and rivers, Branchiobdella italica, B. astaci, B. parasita and B. hexodonta were isolated. Heavily damaged gills in the presence of branchiobdellid cocoons were observed in the crayfish found dead in Orvenco creek.Hyaline and dematiaceous hyphomycetes were frequently observed and Fusarium spp. and Saprolegnia sp. were isolated from cuticular lesions.Mortalities occurred in two tanks, after 2 and 4 weeks respectively, in the adult crayfish coming from Bidente River utilized for breeding, with approximately a 23.5% cumulative mortality rate. In both cases the crayfish were weak, anorexic and lethargic. Bull. Fr. Pêche Piscic. (2006) 380-381 : 1271-1290 -1272 -Four and eight moribund samples respectively, coming from the two breeding tanks in which the mortalities occurred, underwent examination. In the first case the mortalities were attributed to Thelohania-like organisms and in the second case the mortalities were associated with enteric bacteria Citrobacter freundii.Key-words: white-clawed crayfish, Austropotamobius pallipes complex, diseases, Northern Italy. INVESTIGATIONS PRÉLIMINAIRES SUR LES PATHOLOGIES DES ÉCREVISSES À PATTES BLANCHES AUSTROPOTAMOBIUS PALLIPES COMPLEX DANS DES COURS D'EAU DU NORD DE L'ITALIE RÉSUMÉ

Eroded swimmeret syndrome in female crayfish Pacifastacus leniusculus associated with Aphanomyces astaci and Fusarium spp. infections

“…and Fusarium sp. The latter was isolated from the melanised remains of the swimmerets and, based also on other studies (Alderman & Polglase 1985, Chinain & Vey 1988, Vey 1988, Edgerton et al 2002, Quaglio et al 2006, Makkonen et al 2010, Dörr et al 2012, would be the main candidate for consideration as the ESS disease agent.…”

High-throughput discrimination of bacteria isolated fromAstacus astacusandA. leptodactylus

“…Typically, bacteria isolated from crayfish include both Gram-negative and Gram-positive species, as representatives of the genera Acinetobacter, Aeromonas, Bacillus, Citrobacter, Corynebacterium, Flavobacterium, Micrococcus, Pseudomonas, Staphylococcus and Vibrio (Smith and Söderhäll, 1986;Vey, 1986;Alderman and Polglase, 1988;Edgerton et al, 2002;Romero and Jiménez, 2002;Quaglio et al, 2006aQuaglio et al, , 2006bJiravanichpaisal et al, 2009;Longshaw, 2011;Mickeniene and Šyvokiene, 2011). Bacterial infections leading to mortalities have been documented in both farmed and wild crayfish, and were also reported in asymptomatic animals (Edgerton et al, 2002;Quaglio et al, 2006aQuaglio et al, , 2006bCooper et al, 2007;Jiravanichpaisal et al, 2009;Johnson and Paull, 2011;Longshaw, 2011;Longshaw et al, 2012). Mostly, bacteria found in freshwater crayfish inhabit the ecosystem in which they live, may be found in water and sediments, and they reside on the exoskeleton, gills or in the gut.…”

“…Mostly, bacteria found in freshwater crayfish inhabit the ecosystem in which they live, may be found in water and sediments, and they reside on the exoskeleton, gills or in the gut. Bacteriological investigations of crayfish have predominantly been performed on their haemolymph using standard microbiological methods, and also by histopathological examinations of tissues (Colwell et al, 1975;Johnson, 1976;Scott and Thune, 1986;Madetoja and Jussila, 1996;Edgerton and Owens, 1999;Edgerton et al, 2002;Romero and Jiménez, 2002;Quaglio et al, 2006b;Jiravanichpaisal et al, 2009). When performing health status evaluations, considering correct identification and treatment of bacterial diseases and conditions, of (primarily) farmed crayfish, speed is always an issue.…”

Fossil clitellate annelid cocoons and their microbiological inclusions from the Eocene of Seymour Island, Antarctica

“…Few branchiobdellid (crayfish worm) cocoons have been illustrated or described in previous studies. However, at least some cocoons attributed to this group are elliptical, with a smooth to weakly filamentous or scabrate outer layer, and at least one prominent polar extension forming an attachment to the commensal crayfish host (Quaglio et al, 2006;Geasa, 2014) (Figure 11.3).…”