Bull. Eur. Ass. Fish Pathol. 6 (4), I JO, 1986
Amyloodinium ocellatum INFESTATION IN YELLOW­
TAIL, Serio/a dumerili, INTENSIVELY REARED IN
SICILY, ITALY
By P. AJELL01 AND A. D'ALBA2
(Brown,
salinity was 380Jo ( ± 2). The fish affected
1931) (Blastodinidae: Dinoflagellida) is a
by the disease showed a loss of appetite
parasitic dinoflagellate that may cause
and
serious
swimming. Externally the skin had areas
Amyloodinium
ocellatum
mortality
in
marine
fish
in
aquaria.
In
of
Italy,
the
first
case
of
serious
weight
and
depigmentation,
an
incoordinate
especially
·on
the
head, and fin erosion. The gills appeared
oodiniasis was reported by Ghittino et al.
anaemic and in some fishes there was
(1980) in intensive reared juvenile seabass
necrosis of the gill epithelium. In each
(Dicentrarchus labrax). The disease was
tank
also observed in hatchery-reared gilthead
mortality more than 800Jo.
seabream
The
dinoflagellate
Amyloodinium
ocellatum was identified by microscopic
(Sparus aurata) (Barbaro and
Francescon, 1985).
In October 1985, a serious mortality of
yellowtail
(Serio/a dumerili) was reported
the
prevalence
was
the
examination of smears of skin and gills
(Fig. 1).
Subsequently, in seabass and gilthead
in an intensive fish farm in Sicily.
The yellowtail had been caught in the
sea in September of the same year and
then placed in two farm tanks (100 m3),
seabream placed in different tanks, the
same disease was observed.
These fish were treated with 0. 75 ppm
300 fish in each. Their mean weight was
copper sulphate
150 g.; the water temperature l 7°C
continuous application for
in September, l 3°C
1OOOJo,
( ± 2)
( ± 2) in October; the
(Paperna
1984), with
6 days. This
successfully eliminated the parasite.
.I
Fig.
I.
Bull. Eur. Ass. Fish Pathol.
Prophylaxis treatment consists of quar­
antining fish newly introduced to the fish
farm, improving management practices
(lower stocking density, cleanliness) and
treatment with 0.3 ppm copper sulphate
every fifteen days during the months in
which the disease
frequently occurred
(Giorgetti - 1986).
6
(4), 111, 1986
A c kn owl e dge m e n t s
The authors thank Mr. Pietro Arculeo, laboratory
technician for his co-operation and assistance.
Refere nces
Barbaro A. and Francescon A. (1985). Parassitosi
da Amyloodinium ocel/atum (Dinophyceae)
-
N.
5: 745-752.
Ghittino P., Bignami A., Annibali A. and Boni
Juvenile sea bass, for example, might
be treated from April to September.
su
larve di Sparus aurata allevate. Oebalia, XI 2,
L.
( 1980). Prima segnalazione di grave Oodiniasi
in branzini (Dicentrarchus labrax) allevati inten­
sivamente in acqua salmastra. Riv. It. Piscic.
Ittiop., XV: 122-127.
Sum m ary
The
parasitic
ocella1u111 caused
intensively
dinoflage llate
more
reared
than
A111y/uodi11 i u111
mortalit y
80%
yellowtail.
A
in
therapeutic
treatment by conti nuous application or 0.75 ppm
copper sul p h ate for
6
Giorge11i G. (1986). Personal comunication.
I. (1984). Chemical control of Amyloo­
diniu111 ocella1u111 (Brown 1981) (Dinoflagellida)
Paperna
infections: in vitro tests and treatment trials
with infected fishes. Aqu acu l tur e 38: 1-18.
days eliminated the parasite.
Prophylactic measures had to be used to reduce
the incidence or the disease.
Authors' addr es se s:
1 lstituto Zoopr ofilat t ico
62 90129 Palermo.
Spe rimen talc dclla Sicilia .. Sczionc di Palermo. Piazza Generale Turba,
-
1
i s t i t uto
Zooprofilattico Sperimcntalc dcllc Vt•nc1ic. Labora1orio di l 1 t io patologia, Via della
Roggia 92 - 33030
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...
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B as ald e lla
di Campoformido. (Lldinc).