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International Journal of Aquaculture, 2013, Vol.3, No.22, 126
-
132
126
Research Report Open Access
Fatty Acid Profiles and Growth of African Catfish Larvae Fed on Freshwater
Cyclopoid Copepods and
Artemia
as Live Starter Feed
P. Chepkwemoi
1
,
G. N. Bwanika
1
,
J. Kwetegyeka
2
,
G. Mbahizireki
1
,
L. Ndawula
3
,
A. A. Izaara
4
1
Department of Biological Sciences, Makerere University, P.O. Box 7062, Kampala, Uganda
2
Department of Chemistry, Makerere University, P.O. Box 7062, Kampala, Uganda
3
National Fisheries Resources Research Institute, P.O. Box 43, Jinja Uganda
4
Mukono Zonal Agricultural Research and Development Institute, P.O. Box 164, Mukono, Uganda
Corresponding author email:
;
Authors
International Journal of Aquaculture, 2013, Vol.3, No.22 doi: 10.5376/ija.2013.03.0022
Received: 26 Jun., 2013
Accepted: 5 Jul., 2013
Published: 22 Jul., 2013
Copyright © 2013
Chepkwemoi. This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Chepkwemoi, 2013, Fatty Acid Profiles and Growth of African Catfish Larvae Fed on Freshwater Cyclopoid Copepods and
Artemia
as Live Starter Feed,
International Journal of Aquaculture, Vol.3, No.22 126-132 (doi: 10.5376/ija.2013. 03.0022)
Abstract
The possibility of utilizing freshwater crustaceans (Cyclopoid copepods) as an alternative live starter feed for African
catfish (
Clarias gariepinus
,
Burchell, 1822)
larvae was explored. Larvae cultured in experimental tanks under ambient hatchery
conditions were tested on three experimental diets for three days following commencement of exogenous feeding: freshly
decapsulated
Artemia
cysts, early stages of Cyclopoids-copepods and a combination of the two. Change in total length measurements
of larvae was used as a measure of growth. Fatty acid profiles of four-day old larvae were determined using Gas
chromatography-mass spectrometry (GC-MS) method. Overall, growth of catfish larvae was significantly different (F=25.94, P<0.05)
across diets. Cyclopoid-
Artemia
-
fed larvae grew faster (9.1±0.89) mm, followed by Cyclopoid-fed larvae (8.8±0.92) mm and
Artemia
-
fed larvae (8.6±0.79) mm. Similarly, significantly high composition of α linolenic acid (LNA), Arachidonic acid (AA), and
Docosahexaenoic acid (DHA) were recorded for Cyclopoid copepods-fed larvae than for
Artemia
-
fed larvae (LNA, F=14.7, P=0.028;
AA, F=12.1, P=0.037 and DHA, F=101.9, P=0.002, respectively). These essential fatty acids play a significant role in the structural,
physiological and functional development of larval fish thus promoting growth. A combination of Cyclopoid copepods with
Artemia
was of an added advantage possibly due to the large-sized
Artemia
that makes catchability easy. These results demonstrated that
partial or total replacement of
Artemia
with Cyclopoid copepods as a live starter feed for African catfish larvae is feasible but call for
further investigations on cost benefit analysis.
Keywords
Clarias gariepinnus
;
Larvae; Cyclopoid copepods;
Artemia
;
Essential fatty acids; Starter diet
Introduction
Aquaculture continues to expand worldwide to meet
increasing human demand for fish following a decline
in capture fisheries (FAO, 2008). The African catfish
(
Clarias gariepinus
,
Burchell, 1822) is a popular
species for aquaculture in sub-Saharan Africa, and in
Uganda, 60% of aquaculture production is owed to its
culture (FAO, 2006). The African catfish, like other
sensitive first-feeding larvae, faces considerable
challenges in larval nutrition, (Cahu and Infante, 2001;
Takeuchi, 2001; Infante and Cahu, 2001). The larval
stage is a critical stage in a fish’s life cycle that
necessitates an appropriate exogenous nutrition once
the embryonic yolk is used up. Larvae of most
cultured species are generally poorly developed in
physiological and morphological capacities incapacitating
their use of manufactured feeds. As such, culture of
appropriate and adequate quantities of live food is
important in larval rearing of many aquaculture
species (Whyte et al
.
, 1989;
Santiago et al., 1989).
This stems from the fact that live foods do not only
carry adequate supplies of macro-micronutrients,
vitamins and sometimes antibiotics, but also provide a
medium of enzymes that facilitates digestion
(
Lubzens, 1987).
The supply of shelf Brine shrimp (
Artemia
)
cysts
forms the basis of hatchery-based catfish seed
production in Uganda. However, this does not go
without challenges. The existing monopoly of this
product on the market combined with costs associated
with its importation into the country and unpredictable
market supply impacts greatly on the costs of catfish
seed production that makes it untenable for upcoming
hatchery operators. Secondly, continual low survival
rate (15%) of hatchery-based catfish seed has been
