Culture of Zooplankton (Brachionus Calyciflorus, Moina Micrura And Daphnia Pulex) As Live Food for Heterobranchus Bidorsalis Hatchlings.
ABSTRACT
Live food Zooplankton population density in different zones of Awuma River at Shabu was investigated and Brachionus calyciflorus, Moina micrura, and Daphnia pulex screened from the littoral zone of the River at Shabu before the onset of the rainy season was isolated into the monospecific culture in the laboratory.
Cow dung, chicken droppings, groundnut cake, soybean cake, rice bran, and single super phosphate were combined in different proportions of three, four, and five combinations of manure in solution in three replicates for a culture period of 9, 11, and 12 days for each of the zooplankton respectively.
Effects of concentration, a combination of manures, and duration of production of the zooplankton were investigated. Dissolved oxygen, (mg/L) temperature (0C), carbon dioxide (mg/L), and total alkalinity (mg/L) of the water used for the various treatments were monitored.
Chlorella Vulgaris was cultured using the repeated subculture method. Effects of filtrate of the combined manure and C. Vulgaris on the population density of B. calyciflorus and M. micrura were determined.
Influence of temperature on percentage fertilization, hatchability of Heterobranchus bidorsalis eggs, and survival rate of hatchlings was investigated in Jos in a controlled temperature hatchery. The effects of Artemia shell-free, live B. calyciflorus, D. pulex, M. micrura, and a combination of M. micrura & B. calyciflorus on percentage weight gain,
total body length, condition factor, and percentage survival rate were also determined. The fish eggs (500) were mixed with milt and spread on mosquito net kakaban in aquaria in 4 treatments (260C, 280C, 300C, and 320C) in three replicates.
The numbers of unfertilized eggs were counted after 6 hours from the time of mixing of the eggs with the milt. The kakabans were removed after the hatching and hatchlings were counted then and after 3days.
Fry (50) of 3 day-olds were placed in a 10 litre plastic bowl in five treatments of 3 replicates for 16 days. The initial average length (cm) and xvii weight (g) of the fry were recorded. Littoral zone of Awuma River had the highest population density of live food microorganisms.
INTRODUCTION
Naturally, fishes in the wild depend on plankton for the survival of their hatchlings throughout their fry growing seasons. Some zooplankton is essentially used to feed fry of fish species that do not accept artificial feeds (Bryant & Matty, 1980).
Arrhenius and Hanson (1993) reported that some fish species feed exclusively on zooplankton during their entire life while about 90% of foods of herring (Clupea harengus) consist of zooplankton.
Sipaúba-Tavares and Bachion (2002) reported that zooplankton reproduction and growth rate increases the availability of better food quality for subsequent trophic levels.
Live food micro-organisms are important food sources for many fish species and the success of culturing zooplanktivorous fish fry depends primarily on zooplankton, their composition, and density (Fernando, 1994).
Zooplankton, which most fries depend naturally upon as their live food, depends on phytoplankton that constitutes the major primary producer in the aquatic food web. Many species of live food organisms used in larviculture have superior and natural nutritional value than formulated diets.
However, some live food zooplankton are selected as food sources in larviculture based on certain qualities such as purity, availability, acceptance, nutritional indicators (digestibility and organism nutrients/ energy), easy availability, easy reproduction, and economically viability (Watanabe & Kiron, 1994).
Sipaúba-Tavares and Bachion (2002) reported that the culture of Cladocerans offers the possibility of obtaining a large number of live food organisms within short periods of time under optimum conditions of temperature, food, and water quality.
These live food microorganisms are valuable sources of protein, lipids, fatty acids, minerals, and 2 enzymes. They are inexpensive and should serve as an alternative to the brine shrimp which are expensive non-freshwater organisms.
Okunsebor et al. (2008) reported that the survival rate and total body length of Clarias gariepinus fry fed on shell-free Artemia were not significantly different (p<0.05) from those fed on cultured Moina micrura as starter feed.
REFERENCES
Adewunmi, A.A. (2009). Catfish culture in Nigeria: prospects and problems. Aquaculture
Research, 36: pp. 479-585.
Adigun, B.A. (2005). Water quality management in Aquaculture and Freshwater
zooplankton production for use in fish Hatcheries. National Institute for
Freshwater Fisheries Research, New Bussa. 25pp.
Adewolu, M. A., Ogunsanmi, A.O. and Yunusa, A. (2008). Studies on growth
performance and feed utilization of two Clarias catfish and their hybrid reared
under different culture systems. European Journal of Scientific Research, 23( 2):
pp. 252-260.
Adeyemo, A.A., Oladosu, G.A. and Ayinla, A.O. (1994). Growth and survival of fry of
African catfish species, Clarias gariepinus (Burchell), Heterobrachus bidorsalis
(Geoffrey) and Heteroclarias reared on Moina dubia in comparison with other
first feed sources. Aquaculture, 119: 41-45.
AOAC (1984) Official Methods of Analysis of the AOAC, 13th ed. Association of
Official Analytical Chemists,Washington, D.C. 1285 pp.
APHA/AWWA/WPCF (American Public Health Association, American Water Work
Association, Water Pollution Control Federation 1985) Standard methods for the
examination of water and waste water, 16th Edition, Washington, DC, American
Public Health Association, 1268p.
Arimoro, F.O. and Ofojekwu, P.C. (2003). Incidence of feeding, growth and survival of
the toothed carp, Aphyosemion gairdneri larvae reared on the freshwater rotifer, B.
calyciflorus. Tropical Freshwater Biology, (12, 13): 35-43.
Arimoro, F.O. and Ofojekwu, P.C. (2004). Some aspects of the culture, population
dynamics and reproductive rates of the freshwater rotifier, B. calyciflorus fed
selected diets. Journal of Aquatic Sciences, 19 (2): 95-98.
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