International Journal of Marine Science2016, Vol.6, No.31, 1-7
1
Research Article Open Access
Comparison of Spawning Rate between Wild and Improved Strain of
Oreochromis shiranus
(Boulenger, 1897)
David Mbamba
1
, Kumbukani Mzengereza
2,
, Wales Singini
2
, Fanuel Kapute
2
, Hastings Zidana
1
1. National Aquaculture Centre, P. O. Box 44, Domasi, Zomba, Malawi
2. Mzuzu University, Department of Fisheries Science, P/Bag 201, Luwinga, Mzuzu, Malawi
Corresponding author email
International Journal of Marine Science
2016, Vol.6, No.31do
Received: 01 Jun., 2016
Accepted: 20 Sep., 2016
Published: 21 Sep., 2016
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
:
Mbamba D., Mzengereza K., Singini W., Kapute F. and Zidana H., 2016, Comparison of Spawning Rate Between Wild and Improved Strain of
Oreochromis
shiranus
(Boulenger, 1897), International Journal of Marine Science, 6(31):1-7 (doi
Abstract
The study was conducted to determine the spawning rate of Malawian Tilapia,
Oreochromis shiranus
bred in hapas and
placed in ponds at the Malawi’s National Aquaculture Centre (NAC). Two strains compared were improved strain from fifth (F5)
generation brooders which were procured from a selective breeding program and the wild strain. The brood stock fish were grouped
into 3 size categories (24-59g which was designated as treatment 1), 60-99g brooders were denoted as treatment 2 and treatment 3
comprised of brooders that were >100g. Two reproductive parameters were measured every fortnight: number of eggs produced and
condition factor (CF) of the fish. The results showed no significant differences in the number of eggs produced between improved and
wild strain (P<0.05). The study has demonstrated the significance of using body weight and standard length in selecting both wild and
improved strain as a selection criterion for brooders in Malawian Tilapia aquaculture industry.
Keywords
(F5) Generation brooders;
Oreohromis shiranus
; Malawi; Aquaculture; Standard length
Introduction
Fish is the most important source of animal protein in Malawi comprising 60–70% protein (Balarin, 1987).
However, due to the dwindling catches from natural water bodies, fish consumption has declined from 14.9 kg to
around 4.6 kg per capita (GoM, 2013). Development of a resilient and sustainable fish farming industry in Malawi
would be significant to the economy and food security of the country. The decline in wild fish supply has had
serious and detrimental consequences to the health and nutritional standards of many Malawians. However, the
flourishing of fish farming in Malawi as an alternative to dwindling wild stocks is dependent on many factors such
as quality and adequate number of fingerlings as inputs. Good quality and adequate fingerling production remains
a significant bottleneck to continued expansion of aquaculture development in Malawi. Despite that Tilapia
aquaculture continues to expand and represents an important source of fish to domestic and export markets
(Webster, 2006), the supply of adequate number of quality fingerlings poses a challenge in its advancement.
Most cultured Tilapias in Malawi are grouped into two genera (Trewavas, 1982) Tilapia which are macrophagous
and substrate spawners and
Oreochromis
which are microphagous and mouth brooders. The term Tilapia in other
cases was referred to
Oreochromis
species before the separation into its distinct genus. The present study focused
on
Oreochromis shiranus
which is cultured by over 90% of the fish farmers in Malawi either in monoculture or
poly culture with other species (NAC, 2004). Tilapia species (
Oreochromis
species
included), have an excellent
aquaculture potential because of their herbivorous and omnivorous feeding habits, high tolerance to wide range of
water quality, ease of handling, resistance to diseases and parasites (ICLARM, 1991).
The need to develop effective criteria for brood stock selection is pre-requisite for mass fingerling production for
Oreochromis shiranus.
The knowledge of effect of body weight and length on spawning cannot be over
emphasized because it is a positive step towards rapid expansion of aquaculture in Malawi.
The selection of brooders of
Oreochromis shiranus
with potential to give optimum number of eggs is necessary in
fingerling production. Apparently, there is paucity of information on number of eggs that a specific size of either
