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FEEDING AND NUTRITION IN EUROPEAN PERCID FISHES - A REVIEW
Patrick Kestemont', Xueliang Xul, Gersande Blanchard', Charles MWlard2, Murielle
Gielen2, Jean Brun-Bellut3 and
Pascal Fontaine3. 1. The University of Namur, Belgium. 2. University of Liege,
Belgium. 3. Universit6 H. Poincar6,
Nancy, France, patrick.kestemont(tfundp.ac.be.
Introduction. In Europe, two species belonging to
the Percidae family are currently under investigation
in aquaculture: the Eurasian perch Perca fluviatilis
and the pikeperch Stizostedion (or Sander)
lucioperca. Despite the fact that both species are
highly prized food fish, feeding and nutrition of
Eurasian perch and pikeperch are still in their
infancy. Indeed, few publications deal with the
nutritional requirements of European percid fishes,.
and most of them focus on Eurasian perch. Short
reviews of percid feeding and nutrition have been
published by Barrows and Lellis (1996), Brown et al.
(1996), Kestemont et al. (1996), Kestemont and
M6lard (2000) and Brown and Barrows (2002). The
present paper summarises the main nutrition issues
related to broodstock management, larval rearing and
juvenile ongrowing in European percid fishes since
the PERCIS II conference held in Vaasa in 1995.
Broodstock nutrition. Reproductive performances
of Eurasian perch are largely affected by the origin of
breeders, wild or captive. Survival of captive females
prior to ovulation or after spawning are low, and egg
and larval quality are poor, often ranging between 0
and 5%, regardless of spawning period (normal or
out-of-season) (Migaud et al., 2003). It has been
suggested that gamete quality of Eurasian perch
could be improved by improving broodstock
nutrition. Performances of breeders held during their
entire  vitellogenesis  period  in  recirculating
aquaculture system under natural profiles of day
length and temperature, and fed different formulated
diets enriched with vitamin E, vitamin C or HUFA
were compared to performances of breeders fed
natural food (NF, chironomid larvae and prey fish) or
reared in ponds (C). Survival rate of breeders fed NF
was significantly higher than in the other groups.
Both diet and culture conditions significantly affected
performances of Eurasian perch breeders, since
fertilisation and hatching rates were maximal in fish
reared in ponds, but differences between NF and
formulated diets were also significant. The better egg
quality of fish fed NF can be related to an
improvement in their biochemical composition,
namely the level of thyroid hormone (T3) as well as
the K+/Mg' and K7/Na+ ratios. Total lipid content and
fatty acid composition of eggs were, however, not
significantly different between treatments.
More research is still needed in order to improve
broodstock nutrition and management in captive
Eurasian perch breeders to secure high quality eggs
and larvae. To our knowledge, there is no data
available regarding the influence of dietary treatment
on reproductive performances and the nutritional
requirements of pikeperch breeders.
Larval nutrition. No specific larval nutrition
investigations have been performed recently in
Eurasian perch and most research efforts have been
paid to improve survival and growth rates, and
minimise cannibalism (Fiogbd and Kestemont, 2003,
Kestemont et al., 2003). Up to date, Eurasian perch
larvae are still fed Artemia nauplii until they reach 50
mg b.w., and then can be trained to dry feed usually
formulated for marine fish larvae. However, the main
pancreatic and intestinal enzymes are efficient from
early developmental stages, suggesting that a
compound diet could be provided very early to perch
larvae  (Cuvier-Peres  and  Kestemont,  2002).
Dynamics of total lipids and fatty acids during
embryogenesis and early larval development suggest
that docosahexaenoic acid (DHA), and to a lesser
extend, eicosapentaenoic acid (EPA), play a major
role during early life stages of Eurasian perch and
must be present at a sufficient level in larval diets to
support growth performances (Abi-Ayad et al.,
2003). In pikeperch, recent investigations have
compared different diets as initial food and
determined the optimal weaning time to dry diet.
Enrichment of Artemia nauplii with vitamin C and
HUFA is recommended since it reduces significantly
morphological deformities (compared to standard
Artemia or dry feed) and support high growth rate
(Xu et al., this book). It has been also suggested that
a formulated feed should be introduced at the day 19
post-hatch in order to avoid some essential nutrients
deficiency leading to morphological deformity
(Kestemont et al., 2002).
Nutrition of juveniles and adults. While
requirements of some indispensable amino acids have
been determined recently for yellow perch (for
review, Brown and Barrows, 2002), there are few
published nutritional requirements for European
percids. Fiogbe et al. (1996) estimated the protein
requirements of Eurasian perch as 36-56 % of the
diet, depending on mathematical model chosen , and
recommended 40-49% in practical diets. Lipid
nutrition is another major concern in Eurasian perch,
since high lipid diets usually formulated for
salmonids can support rapid growth but are
susceptible to impair liver function by excess storage
of fat into the hepatocytes. Kestemont et al. (2001)
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