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Report 2 (of 6): Hungary for
Fish - Hungary
Introduction
Breeding and cultivation of common
carp (Cyprinus carpio) has been the backbone
of fish farming in Hungary for many years - approximately
two-thirds of the total aquaculture production. Szarvas,
located in southern Hungary, is a region with a particularly
long tradition of fresh water fisheries. However,
attempts to boost productivity without damaging the
natural environment has led many in the region to
seek an alternative fish to farm. Luckily, Szarvas
is home to a fisheries research institute that has
been developing efficient fish-pond technologies based
on organic matter recovery.
The Hungarian Fisheries Research Institute
or HAKI, which belongs to the Ministry of Agriculture,
is a leading institute in aquaculture and fisheries
research in Hungary. Through their work, HAKI has
found a fish more suited to intensive fish farming
than the traditional common carp. The African catfish
is proving to be one of the most ideal aquaculture
species in the world. A hardy, adaptable and a pioneer
of the fish species, it can not only adapt its feeding
habits based on food availability, but it is also
able to withstand harsh conditions and is easily farmed
in capitivity.
Fish Farming in Hungary
Hungary is a typical land-locked country
of Central Europe, located in the Carpathian Basin.
Freshwater fish are a very popular food in Hungary
based largely on cooking traditions. The climate and
geography of the country make it particularly suitable
for the development of pond farming. Ponds are often
constructed on areas too difficult to use for other
farming purposes, on alkaline soils for example. The
most important type of fish farmed in Hungary is the
common carp (Cyprinus carpio L.), as in many
other central European countries. Breeding this fish
has a long tradition in Hungary and its techniques
have been known and used worldwide in carp breeding
programs. Yet pressures to increase production and
questions about breeding quality, together with technology
advancements, has led some to try potential alternatives.
HAKI and the Akvapark Association
The Hungarian Fisheries Research Institute
or HAKI has played an important role in developing
intensive fish production systems in Hungary. Research
is carried out on foreign species such as sturgeon,
catfish and tilapia as well as species native to Hungary,
such as the common carp. HAKI's research and development
has been spread throughout the country through the
government's Ministry of Agriculture.
The Akvapark Association is a Non-governmental
Organisation or NGO set up by HAKI, comprising of
small-scale private enterprises that act as the business
side of the institute's work. The main objective of
the Association is to coordinate available aquaculture
facilities and to conduct joint research and training
programs between members. The Association includes
companies involved in agricultural farming, duck breeding,
vegetable oil production, fish farming and fish pond
construction.
Szarvas Fish
As part of the Akvapark Association,
the Intensive Warm Water Fish Farm, also known as "Szarvas
Fish" is one of the small-scale private enterprises.
The company produces, processes and markets mainly African
catfish because of their ability to breathe air out
of water. The fish are fed by automatically at l0 -
60 minute intervals and consume a diet containing 42-48
per cent protein. This is why African catfish have one
of the least fat contents of any fish. The farm produces
and sells African catfish as fry, fingerlings, market
fish or in processed form on ice, deep-frozen or smoked.
African Catfish
The African catfish, Clarias gariepinus
is a freshwater fish originally from Central Africa,
and is widely considered to be one of the most important
tropical catfish species for aquaculture. They traditionally
inhabit calm waters from lakes, streams and rivers
to swamps and floodplains. African catfish have traditionally
been farmed for almost 20 years on the African continent,
but this has not proved particularly successful due
to unreliable production techniques. In many other
countries such as China, India, Brazil, Hungary and
The Netherlands where appropriate techniques and technologies
do exist, breeding these fish has proved very worthwhile.
The catfish looks similar to an eel
in shape, having a long cylindrical body with very long
dorsal fins. It is more likely to be recognised however,
for its four pairs of unbranched barbels. The African
catfish is known for possessing some uncommon characteristics
that make it particularly suitable for intensive fish
farming.
The most common habitats frequented
are floodplain swamps and pools in which the catfish
can survive during the dry seasons due to a special
air-breathing organ that functions like a lung. This
allows the fish to get its oxygen out of the air so
there is no need for devices to put oxygen into the
water, as needed for other farmed fish. This respiratory
organ is composed of two pear-shaped air chambers
containing two branched structures. These cauliflower-like
structures are supported by cartilage and covered
by tissue that can absorb oxygen from atmospheric
air. The accessory air-breathing organ allows the
fish to survive for many hours out of the water or
for many weeks in muddy marshes.
Catfish can be grown at very high
densities due to a number of reasons. They are air-breathers,
making oxygen demand easy to meet, they have a relatively
high tolerance to poor water quality and have an unusual
behavioural response in that they are not aggressive
in large numbers. This is because they 'school
up', lying stacked on top of each other with their
skins touching. In this situation they show little
or no aggression.
Taste
The flesh of African catfish is tasty,
free of any off-flavour and fish-bones. It has a mild
taste and a firm texture that doesn't fall to pieces
when prepared. The fish meat is lean with around 2-4
per cent fat (most of it unsaturated fatty acids),
and a high protein level of approximately 18-21 per
cent. The fish has such a mild, almost neutral taste,
that it goes well with potatoes, rice and vegetables.
With the absence of a strong fish smell while preparing,
catfish fillets are often favoured to regular sea-fish.
Typical nutritional value per 100
grams:
| Fat |
2.5 grams |
| Protein |
17.3 grams |
| Iron |
0.3 milligrams |
| Vitamins |
A and B |
| Calories |
108 |
Geothermal Aquaculture
Aquaculture is the farming of aquatic
organisms such as fish, shellfish and aquatic plants,
in natural or controlled marine or freshwater environments.
Most research work into aquaculture is carried out
at the HAKI institute in large systems that are water-efficient
and environmentally friendly, by recycling the water
in which the fish are grown. Natural heat from within
the Earth or geothermal energy as it's known
provides a clean and reliable way to heat water in
the tanks.
The aim of geothermal aquaculture
is to heat the water to the optimum temperature for
fish growth. It is particularly suitable for fish
farming because fish require heating at lower temperatures
where there is an abundance of geothermal resources.
Catfish reach their optimum growth rate at approximately
32ºC (90ºF). The use of geothermal energy for raising
catfish, shrimp, tilapia, eels, and tropical fish
has produced crops faster than by conventional solar
heating. Using geothermal heat allows better control
of pond temperatures, which in turn optimises growth.
The Szarvas farm comprises of six
40 metres cubed (m³) volume tanks, five 120 m³ tanks,
two 150 m³ tanks, two 18 m³ tanks and one 24 m³ tank,
a fish storage basin, a fish hatchery and a small
fish processing plant. The farm is supplied by four
groundwater wells that provide geothermal energy and
release water at a rate of 2,000 litres per second.
The temperature of the water flowing through the tanks
is kept constant at 24 degrees celsius (ºC), both
in winter and in summer, which enables to catfish
to grow to a good size in a short space of time.
For further information on fish farming
in Hungary, please contact:
HAKI
H-5540 Szarvas
Anna-liget 8.
H-5541 Szarvas
P.O. Box 47
Hungary
Tel. +36 66 525 300
Fax +36 66 312 142
Email: info@haki.hu
Website: www.haki.hu/english |
SZEGEDFISH Ltd.
P.O. Box 50
H-6701 Szeged
Hungary
Tel. +36 62 461 444
Fax +36 62 469 109
Website: http://www.szegedfish.hu/
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Websites
cdserver2.ru.ac.za/cd/catfish/catfish
The biology and culture of the African Catfish
http://www.aquaflow.org/
European Network for the dissemination of Aquaculture
information
www.uaex.edu/aqfi/page12.html
Aquaculture/Fisheries links
http://www.planetcatfish.com/
Further Reading
Handbook on the artificial reproduction
and pond rearing of the African catfish clarias gariepinus
in Sub-Saharan Africa
Gertjan De Graaf and Johannes Janssen, Nefisco Foundation
FAO Fisheries Technical Paper 362
1996
This paper can be downloaded free
at: www.nefisco.org/downloads/Clarias.PDF
This document is an output from
a project funded by the UK Department for International
Development (DFID) and the European Commission (EC)
for the benefit of developing countries. The views
expressed are not necessarily those of DFID or the
EC.
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