Presented by
M. AI Magsoudi
MBRC/LIBFISH
Aqua Component Group
1. INTRODUCTION
There is little use of zooplankton as a live feed for fish in Libya, though Artemia sp. arc fed to decorative fish to some extent. With the prospect of aquaculture development on a wider scale, however, it is appropriate for national fisheries staff to be trained in zooplankton culture techniques.
2. WORK AT MBRC
2.1 Identification of Libyan Species of Artemia
Artemia sp., the most widely used live feed in aquaculture production, occurs naturally in different places in Libya, especially along the coast (Abu Kamash, Tawargah and El-Kuwain Sebkha) and in salty lakes located in the Awbari region of the southern desert (Magsoudi and Vallet, 1994).
No taxonomic work has yet been carried out on Artemia in Libya, although it is well known as traditional food and medicine in the desert. Specimens of various origins have been collected and sent for further study to the Artemia Reference Centre of the University of Ghent. Belgium.
2.2 Isolation of Local Strains of Artemia
Specimens collected in three different sites (Abu Kamash. Tawargah, Awbari) have been cultivated in five-litre jars, being fed on Chlorella culture. The purpose of this work is to isolate pure strains of Artemia.
2.3 Comparison of Cyst ‘Hatchability’
Cysts have been collected in Abu Kamash Sebkha, which is the only Libyan site where Artemia is present and produces cysts. Their ‘hatchability’ has been compared some purchased from a Belgian commercial supplier. It appears that the hatching rate of the ‘Abu Kamash brand’ is not as good as the one of the commercial brand. Possible reasons for this are improper harvesting and cleaning methods and unsuitable storage conditions.
2.4 Production of Live Feed
Artemia: a few nauplii and adults have been collected from Abu Kamash and from Tawargah Sebkha and from Awbari salt lakes. They have been cultivated in 1000 litre-tanks and fed with ‘green water’ (mainly Chlorella) produced by the Aqua component team for further use as fish feed at the MBRC.
Rotifers: a pure strain of Brachionus plicatilis has been obtained from the Malta National Aquaculture Centre and cultivated in five-litre jars with Chlorella. They have been used to feed a few fish fry kept at the MBRC aquarium, and are being kept for further mass production to be used in the planned fish hatchery.
Daphnia sp.: samples were collected from a Tajura salt marsh in 1986 and since been raised in an outside 5 m3 concrete tank. The production is used for feeding small fishes kept at the MBRC display aquarium.
3. CONCLUSION
Continuous production of a few species of zooplankton is carried out on a routine basis at the MBRC in order to feed fishes grown in the display aquarium and experimental tanks. A few improvements to the production effort should be seen to, including:
Cleanliness of the laboratory in order to avoid any possible contamination of the cultures by micro-organisms.
Upgrading of the equipment for mass production.
Installation of a special room for live feed production.
