|SPORE Bulletin of the CTA No. 08 - January 1987 (CTA - Technical Centre for Agricultural and Rural Cooperation, 1987)|
With the intensification of pig production in some countries and the consequent problem of disposing manure, there is considerable interest in the traditional Chinese method of raising fish in ponds by feeding them with pig manure. Researchers at the Asian Institute of Technology have been investigating the system and have found it is best suited to warmer areas of the world, where water temperatures exceed 20°C. The fish species most appropriate to the system are Chinese and Indian carp, common carp, tilapia, mullet and silver-striped catfish.
Pig manure itself has little value for the fish, but its fertilizing effect encourages the growth of phytoplankton, which is filtered out of the water by the fish. The production of phytoplankton does, however, brings problems. Photosynthesis can lead to high oxygen levels during the day but at night the oxygen is taken up by the phytoplankton. When oxygen levels fall to zero by the morning, this can be critical for some species of fish.
In Thailand, a yield of 5 tonnes of tilapia has been harvested annually from one hectare in ponds manured by 150 pigs.
Yields can be further boosted with the use of supplementary feed, such as soya bean cake, rice bran and pelleted feed
For further information consult:
Pig International Sept 1985 Watt Publishing Co 18 Chapel Street Petersfield Hants GU32 3DZ IIK
A cheap water treatment system for Sudanese Gezira villages
The Sudanese authorities are now drawing plans to built a new filtration plant using broken bricks as a simple and cheap solution to the problem of providing clean water in Sudan's irrigated Gezira area.
The population of this area related to the use of polluted canal water. In the new filtration plant canal water passes through a concrete tank containing broken locally made bricks, then through a horizontal roughening filter, and finally a standard slow filter. Clear water is handpumped from the tank
The Blue Nile project supplies the new filter to each village at a cost of about 2,400 US dollars. The plants are constructed by the villagers and one person in each village is trained in the basic maintenance of the filter and pump. All parts of the system are produced locally except plastic pipings and pumps.
There are 450 registered villages in Gezira and approximately 500 camps without proper water supply Despite the low costs, financial problems are the main constraints for its ranid adoption
More grain legumes for Africa
The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India, will increase its presence in Eastern and Central Africa for grain legume promotion, reports the institute's bulletin. A consultative group meeting on Grain Legumes, held at the International Livestock Centre for Africa (ILCA), Ethiopia, last December, proposed three alternative mechanisms under which ICRISAT could operate in the region.
It was recognized that ICRISAT already responds to individual national requests for germoplasm, training, information and scientific assistance.
The meeting brought together some thirty-five scientists who reviewed on-going research programmes in this African region on three grain legume crops: chickpea, groundnut and pigeonpea
Participants included representatives from national programmes of Burundi, Ethiopia, Kenya, Rwanda, Sudan and Uganda as well as from research and donor organizations. There was unanimous agreement that the priorities of all national programmes with respect to these three crops include:
- Germplasm collection, exchange and evaluation
- Training at both scientific and technical levels
- Strengthening of national programmes and regional cooperation.
ICRISAT has announced that it is to produce the 'International Arachis Newsletter', in collaboration with the Peanut Collaborative Research Support Programme (Peanut CRSP). It will report a range of topics relevant to groundnut (Arachis hypogaea). It will be published in May and November. All communications and requests should be sent to
The Editor International Arachis Newsietter, ICRISAT
For further information, contact:
International Crops Research Institute for the Semi-Arid Tropics ICRISAT Patancheru
Andhra Pradesh 502 324 India