American Journal of Innovative Research and Applied Sciences. ISSN 2429-5396 I www.american-jiras.com
138
| Saviour Isonguyo Umanah
1
| and | Tony Dapa
2
|
1.
University of Uyo | Department of Fisheries and Aquatic Environmental Management | Uyo | Nigeria |
2.
University of Uyo | Department of Fisheries and Aquatic Environmental Management | Uyo | Nigeria |
|Received | 09 July 2017| |Accepted | 18 July 2017| |Published 24 July 2017 |
ABSTRACT
Background: Stocking density refers to the weight of fish per unit volume or the number of fish stocked at the beginning of an
experiment. Available space and adequate water for exchange are two factors which could greatly affect the productivity of aquaculture
in conjunction with the target species, hence, must be optimally utilized. Objectives: African Sharptooth catfish, albino Clarias gariepinus
was cultured at four different densities in collapsible tanks to evaluate the effect of stocking density on growth response, survival rate
and feed utilization. Materials and methods: Two hundred and seventy (270) fish with initial weight of 1.09g, 0.80g, 0.61g, 0.71g
were stocked at 15/m
2
, 20/m
2
, 25/m
2
and 30/m
2
respectively. The experiment lasted for 140 days. The experimental fish were fed 6%
of their body biomass daily and the weight and length were taken biweekly while the physico-chemical parameters were recorded weekly.
Results: The final mean weights of the fish stocked at stocking densities of 15/m
2
, 20/m
2
, 25/m
2
and 30/m
2
were 104.21 ±10.38g,
106.65 ± 11.04g, 110.23 ± 23.68g and 78.88 ± 7.58g respectively. The corresponding mean values of specific growth rate were 0.03,
0.04, 0.03, 0.03. The feed conversion Ratio (FCR) was 1.62, 1.06, 1.36, 1.29 and survival rates were calculated to be 82.22%, 85%,
45.67% and 60% accordingly. At the end of the experiment the result showed that the survival rate of the stocking densities of 15/m
2
,
20/m
2
and 30/m
2
were not significantly different (P>0.05) but stocking density 25m
2
was significantly different (P<0.05) from stocking
densities 15/m
2
, 20/m
2
and similar to stocking density 30/m
2
, stocking density 25/m
2
had the highest mean weight gain (110.23g ±
23.68) compared to the other treatments which was the best. Conclusion: It was concluded from the results that high stocking densities
had negative impacts on the growth performance and feed utilization of the albino Clarias gariepinus.
Keyword: aquaculture, fish, survival rate, proximate composition
1. INTRODUCTION
Aquaculture refers to the breeding, rearing and harvesting of plants and animals in all types of water environments including
ponds, rivers, lakes and the oceans [1]. Fish culture being an integral subset of Aquaculture is fundamentally important for
reliable generation of fish to meet human nutritional needs. Fish provides a relatively cheap source of animal protein when
compared to beef [2]. Fish has long remained an important source of quality protein consumed by the world’s population
[3]. The endeavour to satisfy the high demand for fish in view of its health benefits and the deficiency of the natural waters
to efficiently meet such fish demands have generated a perennially increasing interests in aquaculture. These interests
have consequently lead to mounting pressures on certain cardinal factors of production. Available space and adequate
water for exchange are two factors which could greatly affect the productivity of aquaculture in conjunction with the target
species, hence, must be optimally utilized. Many species of fish have been tried in aquaculture. The African aquaculture
has been dominated by the farming of the Clariid fishes of which the African sharptooth catfish (Clarias gariepinus) is the
most popular and of great economic importance as food fish [4,5]. The species, Clarias gariepinus attracts good prices in
Nigerian markets [6,7], due to its tasty flesh devoid of sharp bones. It is hardy, exhibiting great tolerance for high stocking
density even in low oxygen waters, good growth rate, efficient food conversion and excellent nutritional profile, and
medicinally valuable [8,9,10].
Like many other vertebrates [11], the African sharptooth catfish (Clarias gariepinus), has a synonymous strain, albino C.
gariepinus [12,13]. The albino has pinkish or yellowish body colouration, white belly and red eyes [14]. Albinism is a genetic
abnormally caused by an autosomal recessive gene in the homozygous state resulting in deficit melanin production [15,16].
According to these authors, it can also be induced artificially by exposing the eggs or brood stocks to heavy metals such as
arsenic, cadmium, copper, mercury, selenium, or zinc. Three types of albinism have been identified namely: true (total or
complete) albinism, marked by total absence of melanin, normal skin and eye pigmentation; leucism, in which exists
abnormal skin pigmentation but normal eye colour; and partial albinism recognized by restricted normal skin colour but
normal eye colour [15-14-17,18,19]. While the other authors regarded leucism as partial albinism, Miller (2005) classified
them as distinct. The albino fishes are prominent as ornamental fishes due to their striking appearance [18].
The future of aquaculture in Africa lies in producing more fish using less land, water and financial resources [20]. In
aquaculture, fish growth rate determines fish size and production which affect the price of fish [21]. Most fish culturists
THE EFFECT OF STOCKING DENSITY ON THE GROWTH
PERFORMANCE AND FEED UTILIZATION OF ALBINO Clarias
gariepinus REARED IN COLLAPSIBLE TARPULIN TANKS
*
Corresponding and author Copyright © 2017: Saviour Isonguyo Umanah. All Rights Reserved. All articles published in American Journal of Innovative Research and
Applied Sciences are the property of Atlantic Center Research Sciences, and is protected by copyright laws CC-BY. See: http://creativecommons.org/licenses/by-nc/4.0/.