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african fish farmers are benefiting from improved livelihoods and a better food security status， thanks to the introduction of two strains of improved Nile tilapia in Egypt and Ghana.
This follows 10 years of breeding research， culminating in the introduction of the Abbasa strain of the Nile tilapia（Oreochromis niloticus） in Egypt. The species is indigenous to much of Africa. It grows 28 percent faster than most of the common varieties in Egypt， such as the Kafr El Shaikh strain.
The second new tilapia Akosombo strain， which was developed by the Water Research Institute （WRI） in collaboration with WorldFish Center， an international non-profit research organization， and the Food and Agriculture Organization （FAO）， can grow up to 30 percent faster than the non-improved varieties in Ghana.
“Tilapia production in Ghana is projected to increase 10-fold by 2015 as a result of introducing the new strain，” said Dr. Felix Klenam Attipoe， the Officer-in-Charge at WRI.
According to researchers， the short maturity period of the new strains allows farmers to save on labor costs and the costs of feeding the fish.
“In our experience， the improved strains require a little less food and because they grow to market size more quickly， farmers may be able to produce more fish harvests per year，” said Dr. Malcolm Beveridge， Director of Aquaculture and Genetics at WorldFish.
Whereas it takes up to eight months for the non-improved varieties to attain maturity， the new strains take only six months. This in turn has a positive trickle-down effect for the consumer. Beveridge explained that an increase in fish production means prices may not go up as fast as they otherwise would， thereby making fish more affordable to poor consumers. Fish accounts for over 30 percent of total animal protein consumption in the diets of Africa’s poor according to WorldFish research.
“The impact of the improved strains on productivity， profitability， affordability and consumption by poor consumers will differ from place to place， depending on factors such as access of farmers to seeds and to markets and to the volumes of farmed fish that are being sold，” said Beveridge.
Even though the Nile tilapia is the single most popular freshwater fish species in Egypt and Ghana， some experts would rather grow other types of fish.
They feel that growing tilapia has a lot of challenges to overcome when compared to the improved African catfish， for example. The female Nile tilapia incubates the eggs and the newly hatched fry in her mouth for a couple of weeks， during which time she does not feed. She stops growing for a few weeks before spawning， diverting resources she would otherwise use for growth into the production of eggs. Many commercial hatcheries throughout the world treat newly hatched fry with very small quantities of a hormone called methyltestosterone for four-five weeks after hatching to ensure all-male tilapia fish. Small female fish in the pond becomes problematic if there are too many of them because they deprive the male fish of oxygen and nutrients. At any rate， owing to their small size， they will fetch less attractive prices in the market. In addition， the tilapia fish is said to be bony thus its fillet yield is lower than that of the improved African catfish， for example.
However， Beveridge explained that male tilapia do not incur such constraints during growth， which is one of the reasons why farmers prefer growing all-male tilapia fish. He added that the size of the fish is not always that important， and that poorer consumers may opt for the small fish.
Developing better growing strains of fish is only part of the solution to improving supplies of affordable fish through aquaculture to African consumers.
Beveridge acknowledged that problems can occur throughout the feeds value chain： lack of reliable supplies of quality feedstuffs， poor feed manufacturing and inadequate storage and distribution.
These challenges can often be addressed by farmer access to affordable credit. This is where farmers can form producer organizations that “can help increase access to affordable credit， reduce feed costs and help secure better prices when farmers come to sell，” observed Beveridge.
This follows 10 years of breeding research， culminating in the introduction of the Abbasa strain of the Nile tilapia（Oreochromis niloticus） in Egypt. The species is indigenous to much of Africa. It grows 28 percent faster than most of the common varieties in Egypt， such as the Kafr El Shaikh strain.
The second new tilapia Akosombo strain， which was developed by the Water Research Institute （WRI） in collaboration with WorldFish Center， an international non-profit research organization， and the Food and Agriculture Organization （FAO）， can grow up to 30 percent faster than the non-improved varieties in Ghana.
“Tilapia production in Ghana is projected to increase 10-fold by 2015 as a result of introducing the new strain，” said Dr. Felix Klenam Attipoe， the Officer-in-Charge at WRI.
According to researchers， the short maturity period of the new strains allows farmers to save on labor costs and the costs of feeding the fish.
“In our experience， the improved strains require a little less food and because they grow to market size more quickly， farmers may be able to produce more fish harvests per year，” said Dr. Malcolm Beveridge， Director of Aquaculture and Genetics at WorldFish.
Whereas it takes up to eight months for the non-improved varieties to attain maturity， the new strains take only six months. This in turn has a positive trickle-down effect for the consumer. Beveridge explained that an increase in fish production means prices may not go up as fast as they otherwise would， thereby making fish more affordable to poor consumers. Fish accounts for over 30 percent of total animal protein consumption in the diets of Africa’s poor according to WorldFish research.
“The impact of the improved strains on productivity， profitability， affordability and consumption by poor consumers will differ from place to place， depending on factors such as access of farmers to seeds and to markets and to the volumes of farmed fish that are being sold，” said Beveridge.
Even though the Nile tilapia is the single most popular freshwater fish species in Egypt and Ghana， some experts would rather grow other types of fish.
They feel that growing tilapia has a lot of challenges to overcome when compared to the improved African catfish， for example. The female Nile tilapia incubates the eggs and the newly hatched fry in her mouth for a couple of weeks， during which time she does not feed. She stops growing for a few weeks before spawning， diverting resources she would otherwise use for growth into the production of eggs. Many commercial hatcheries throughout the world treat newly hatched fry with very small quantities of a hormone called methyltestosterone for four-five weeks after hatching to ensure all-male tilapia fish. Small female fish in the pond becomes problematic if there are too many of them because they deprive the male fish of oxygen and nutrients. At any rate， owing to their small size， they will fetch less attractive prices in the market. In addition， the tilapia fish is said to be bony thus its fillet yield is lower than that of the improved African catfish， for example.
However， Beveridge explained that male tilapia do not incur such constraints during growth， which is one of the reasons why farmers prefer growing all-male tilapia fish. He added that the size of the fish is not always that important， and that poorer consumers may opt for the small fish.
Developing better growing strains of fish is only part of the solution to improving supplies of affordable fish through aquaculture to African consumers.
Beveridge acknowledged that problems can occur throughout the feeds value chain： lack of reliable supplies of quality feedstuffs， poor feed manufacturing and inadequate storage and distribution.
These challenges can often be addressed by farmer access to affordable credit. This is where farmers can form producer organizations that “can help increase access to affordable credit， reduce feed costs and help secure better prices when farmers come to sell，” observed Beveridge.