The culture of Blackspot
seabream, Pagellus bogaraveo
Aquaflow Technical Leaflet 2002-57
European Network for the Dissemination of Aquaculture
RTD Information (Q5CA-2000-30105) and previously FAIR-3837, URL: http://www.aquaflow.org/
The blackspot seabream (Pagellus bogaraveo) is a
species with a promising future for aquaculture, due to its high market
value, its scarcity in traditional fishing grounds and its biological
characteristics, such as a good capacity to live in captivity, endurance and
low susceptibility to disease. The overall objective of this ongoing project
is the development and optimization of blackspot seabream culture
techniques, in order to determine its practicability for industrial culture.
Three specific targets are focused upon:
a) Obtaining natural and/or induced spawnings.
b) Optimizing larval rearing and weaning techniques.
c) Increasing knowledge on specific feeding
requirements and adequate tanks and cages for ongrowing.
Natural spawning occurs during February and May. At
these periods in the year 2000, 12 million eggs were obtained which came
mainly from broodstock captured from the wild. Natural spawns in 2001
yeilded 19 million eggs, of which only 1 million came from reared
broodstock. The studies on induced spawning are still ongoing, although this
method (i.e. outside the periods mentioned above) gave rise to a total of 2
million larvae in 2000 and 4 million in 2001.
Larval rearing was carried out in the Spanish
Institute of Oceanography (at the Coastal Center of Vigo). The traditional
sparid rearing protocols were adapted and improved in order to meet the
specific characteristics of blackspot seabream. Weaning of larvae was
successfully carried out when larvae were 50 days old, yielding survival
levels of around 20%-30% (entirely weaned fish). Several larval feeding
experiments were conducted and a number of samples were taken to undertake
biochemical analysis. These results will be subsequently used as markers for
nutritional larval condition. The biochemical analysis is being done in the
Marine Research Center of Vilanova de Arousa (Xunta de Galicia-Spain).
The growth performance of juveniles was assessed in
both tanks and sea cages (Consellería de Pesca de la Xunta de Galicia,
Bueu-Pontevedra). The mean weights achieved in the tanks and in the cages,
from a mean initial weight of 34 g and after 24 months, were 395 and 495
grams respectively. Ongrowing experiments are being also undertaken in cages
with two main objectives: to find a suitable diet and to determine the
effect of this diet on the final quality of the product. To meet these
objectives, researchers are comparing the effect on growth of feeds with
different levels (qualitatively and quantitatively) of fat and the same
level of protein, on the characteristically high level of perivisceral fat
deposition of this species when it is fed in captivity and on the flesh
composition of the obtained fish.
For more information:
Dr. Mercedes Olmedo
Instituto Español de Oceanografía Centro Oceanográfico de Vigo
Cabo Estay Canido. Apdo. 1552 36280 Vigo
Spain
Phone : +34 986 462929
Fax : +34 986 492351
E-mail : mercedes.olmedo@vi.ieo.es