Preprint volume - SIBM

Pre-print Volume – Posters
AQUACULTURE COMMITEE
I. TRAVERSI, A. MANDICH, A. CEVASCO, E. FATTORE * , C. GENEROSO * , A. MASSARI
Dipartimento di Biologia, Università di Genova, viale Benedetto XV, 5 - 16132 Genova, Italia.
traversiilaria@gmail.com
* Istituto Mario Negri, Via Giuseppe La Masa, 19 - 20156 Milano, Italia.
MORPHOLOGICAL AND BIOCHEMICAL RESPONSES
TO ENVIRONMENTAL CONTAMINANTS IN FARMED
AND WILD EUROPEAN SEABASS (DICENTRARCHUS LABRAX)
RISPOSTE MORFOLOGICHE E BIOCHIMICHE A CONTAMINANTI
AMBIENTALI
IN SPIGOLA (DICENTRARCHUS LABRAX) ALLEVATA E SELVATICA
Abstract – The presence of environmental pollutants in both wild and cultured fish is cause of concern. The
European sea bass (Dicentrarchus labrax L., Teleostei, Moronidae) represents one of the most diffused
marine species cultured in the Mediterranean areas. Aim of this study was to investigate the relationships
of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDDs and PCDFs), dioxin-like and non dioxinlike
polychlorinated biphenyl (DL and NDL-PCBs) levels in the muscle of wild and cultured sea bass with
morphological and enzymatic activities as biochemical biomarkers of exposure. In farmed fish, levels of
contaminants were lower than those detected in other studies. The low level of contamination was
confirmed both by enzymatic activities and by gonad, liver and gill morphology showing absence of chronic
alterations.
Key-words: environmental pollutants, biomarker, seabass, aquaculture.
Introduction – Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs)
and polychlorinated biphenyls (PCBs) are persistent contaminants widespread in the
environment and animal tissues (Toft et al., 2003). The integrated use of chemical
analysis and morphological/biochemical markers of exposure makes it possible to
study the impact of anthropogenic contaminants and to compare the effects on wild and
reared fish. The aim of this study was to investigate the relationships between PCDDs,
PCDFs, DL-PCBs, NDL-PCBs levels, morphological endpoints in gonads, liver and
gills and glutathione S-tranferase (GST) and Catalase (CAT) activities as biomarkers of
exposure (Van der Oost et al., 2003) in wild (Wsb) and farmed (Fsb) European sea
bass, Dicentrarchus labrax, selected as bioindicator species
Materials and methods – Farmed D. labrax (n=20; 327.13±57.62 g) were collected,
from an off-shore fish farm located in the Ligurian sea, while wild specimens (n=8,
714.7±58.3), were captured nearby the Cinque Terre National Park,both in February-
March 2009. Fish were measured and weighted and the condition factor (CF: body
weight (g) ×100/length 3 (cm)) and the hepatosomatic index (HSI; liver weight (in
g)/body weight (g) ×100) were calculated. Gonad, liver and gill fragments were
Bouin’s fixed and stained with haematoxylin-eosin. Two series of 4 μm thick sections
were analyzed for presence/absence of alteration of connective stroma, granulocyte and
melanomacrophage centres (MMCs) infiltration, haemorrhages, gamete atresia and
oocytes in testis, for gonads; granulocyte and MMCs infiltration, and lipid deposit in
hepatocytes, for liver; alteration of primary lamellae and respiratory lamellae,
haemorrhages, and relative number of chloride cells and mucous cells, for gills.
Chloride cells were identified by using the mouse raised monoclonal ab-Na, K-
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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