6.2 Research needs
6.3 Research approach
Though fish culture integrated with animal husbandry, such as pig or duck raising, is well established in other parts of the world, it is a relatively new system in Africa. Experience so far shows considerable potential for the development of the system, even though it would require much more skill on the part of the farmer than when he raises fish or animals only. In integrated fish culture trials in the Central African Republic with T. nilotica and C. lazera, yields of 7-10 t/ha of fish per year were obtained by the use of manure of pigs raised near the ponds and without feeding. In addition, some 6 400 kg of pig meat could also be raised, contributing substantially to the income from the farm. Because of the reported success, and the widespread interest in integrated rural development aimed at improving the income and standard of living of farmers, fish culture combined with some form of animal husbandry, is now planned in many countries. In view of this, it is recommended that the Centre undertake essential studies for developing a system of integrated fish culture with fish (Tilapia and Clarias) as the major crops, and pigs as a subsidiary crop. Even though duck raising is also well adapted for integration with fish culture, it is not recommended at present, as duck is not a popular food item, and duck farming will be a rather new and unfamiliar activity in most areas.
In order to evaluate the possible role of fish culture combined with pig raising in integrated rural development, the complementary role of the two crops and the increased income and other benefits that a farmer can derive by integration should be clearly demonstrated. This should be the major objective of research in the Centre. The proposed Regional Lead Centre in China to be established as part of a regional network of aquaculture centres in Asia, would be carrying out critical research on the processes involved in integrated farming, and close liaison with that Centre should be established to benefit from the results of studies there.
Although no public health hazards have been recognized so far in this type of farming, this aspect has not yet been properly investigated. Such studies seem particularly warranted in rural areas of Africa.
(i) Determination of suitable ratios of pond area, fish stock density and number of pigs for integrated farming;
(ii) monitoring of water quality, fish food production and utilization;
(iii) determination of minimum size of farming operation required to increase farmers' income to a required level;
(iv) development of suitable methods of integrated farming under African conditions;
(v) determination of health hazards, if any, involved in integrated culture of fish with pigs;
(vi) evaluation of economic and other benefits derived by integrated farming.
An integrated production unit, consisting of a selected number of ponds with pigstys built on its bank, will be necessary for undertaking the necessary experiments. It is suggested that in the initial experiments all-male T. nilotica be used. Later, identical experiments can be conducted with C. lazera and if found useful, with a combination of the two species. Arrangements should be made for comparative studies of the relative merits of direct introduction of piggery wastes into the ponds and the introduction of wastes after fermentation in special tanks. Different ratios of piglets to pond area (say 40-70/ha) should be tried. The pigs, which should be of quick-growing strains (e.g., Large White) should be fed regularly with suitable feeds (if possible, prepared feeds). The quantity of manure produced should be determined and the water quality and fish food production in the ponds monitored. Management measures, like addition of water and aeration, should be adopted, if found necessary.
The economics of the farming and the income and other benefits that can be derived by it, can be determined from the production of fish and pigs obtained, and a proper assessment of operating costs. Based on the results of production experiments, it should be possible to determine the size of operation (pond area, fish stock and pigs) needed for obtaining the' required level of income.
While the monitoring of fish health and diseases can be done by the Centre's staff, assistance of public health personnel may be necessary to examine whether public health hazards are involved, and to undertake necessary precautionary measures. The assistance of a veterinarian and possibly personnel experienced in pig raising may be required at least in the initial stages, to ensure the adoption of appropriate pig raising methods.