Of the farms surveyed, 42% were integrated pig and. fish production farms, on which part or all of the pig. manure was used to fertilize fishponds, and about 10% of. total manure produced on the farms was used for fish. production ( Fig. 4 ) .Liquid Manure from cleaningpigswas directly channelled into fishponds, and solid manure was. either added to the ponds without treatment or composted. for about a week before being used in fishponds. Waste water used for cleaning pigs was discharged into the. fishpond inorder to reduce transportationcosts to thefield