Integrated farming of fish and livestock
Although fish farming is integrated with the husbandry of most domesticated animals, pig and duck raising appear to have been most successful in this respect. In the agricultural economy of China, pigs have a special significance. They are considered as ‘costless fertilizer factories, moving on hooves’, and pig manure forms the main source of home-made fertilizer. So the farmer has to raise them to meet the needs of crop farming, as well as fish farming.
The pig sties can be built on fish farm embank-ments and aquatic plants from the ponds and associated water bodies, along with crop wastes, can be used for feeding the pigs. Part of the pig manure, raw or fermented, can be used very conveniently for fertilizing the ponds and the rest used for fertilizing agricultural fields. From the point of view of utilization of manure, the production of cattle and chicken are also important. As mentioned earlier, duck raising in association with fish farming has proved to be mutually beneficial. The ponds and their embankments provide the space for duck rearing and the ducks fertilize the ponds with their excreta, as well as feeding on unwanted organisms growing in ponds, such as snails, which may be carriers of water-borne diseases.