Preliminary Assessment of Growth Performance and Nutrient utilization of Clarias gariepinus (Burchell, 1822) Fingerlings fed Cirina forda (Westwood, 1849) as Protein Source

The potentials of Cirina forda as a replacement for fishmeal in the diets of Clarias gariepinus&nbsp; fingerlings were evaluated in 56 days. Five diets namely diets A (100% fishmeal and 0%Cirina forda), B (75% fishmeal and 25% Cirina forda), C (50% fishmeal and 50% Cirina forda), D (25% fishmeal and 75% Cirina forda), and E (0% fishmeal and 100% Cirina forda) were compounded and given to the fingerlings at 5% body weight. Growth performance traits and nutrient compositions were measured, recorded and analysed. The highest final mean weight and mean weight gain were obtained in diet E containing 100% Cirina forda while the least values were recorded in diet C at 50% inclusion of Cirina forda. This indicates that Clarias gariepinus can tolerate 100% Cirina forda as a protein source without any inclusion of fishmeal. This will subsequently reduce the cost of feed production in the culture of Clarias gariepinus.</p

Length-Weight Relationship and Fecundity of Clarias Gariepinus in a Tropical Reservoir, Southwest, Nigeria

This study considered the length-weight relationship and fecundity of Clarias gariepinus in Ero reservoir, a tropical reservoir in Ekiti, Southwest Nigeria. Four hundred and eighty eight (488) specimens of the fish species were collected during the period of study spanning between April 2003 and March 2005. Gears employed were gillnets, cast nets, basket traps and hook and lines. Standard length ranged between 29.1 and 33.1 cm, while weight ranged from 225.87 to 373.48 g. The linear relationship of length and weight of the C. gariepinus population showed isometric growth pattern with &lsquo;b&rsquo; values being higher than 3. Mean fecundity was 769. High positive correlation was recorded between fecundity and standard length (r = 0.71, p&lt;0.05) and also between fecundity and weight (r = 0.874, p&lt;0.05). Keywords: Clarias gariepinus, length-weight relationship, Ero reservoir, Nigeri

Preliminary evaluation of some aspects of the ecology (growth pattern, condition factor and reproductive biology) of African pike, Hepsetus odoe (Bloch 1794), in Lake Eleiyele, Ibadan, Nigeria

Abstract A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year