#3930
imported_Martin
Participant

from end of an article online:

Quote:
Fowler and Lock (1974) described the possibility of inclusion of poultry waste as a feed ingredient in catfish ration. Some farmers in Asia build poultry cages on a wooden platform above a fish pond, poultry feed together with spilled feed fall directly into the pond where it is consumed by the fish. This system is very practical, no cleaning of poultry cages is necessary, and poultry situated above the fish pond enjoy an excellent air circulation which has a significant cooling effect for laying birds which are particularly sensitive to heat stress. This system in terms of livestock waste management increases the profit derived from fish and totally eliminates the pollution problem. It is estimated that one laying hen will produce enough manure to generate about 6–8 kg/year of fish biomass. Manure derived from individual confined livestock species (annually) can support the following annual production range of fish biomass (Muller, 1980).

Manure from Fish biomass production (kg/year)
One dairy cow 100 – 200
One beef cattle 90 – 160
One sheep 10 – 17
One laying hen 6 – 8
One replacement bird 4 – 5
One broiler 3 – 4
One turkey 7 – 8

The conversion ratio of manure to fish biomass is related to numerous factors, particularly the fish species, climatic conditions and pond water management.

It can be concluded that fish cultures are an excellent outlet, closing circularly integrated recycling systems without further pollution discharge. This is even more true when fish ponds can be switched over to cropping every second year, a system quite commonly used in Asia. This practice supports both high production of disease free fish and high crop yields.

In Alabama, Nerrie and Smitherman (1979) used pelleted chicken manure to feed tilapia stocked at approximately 10,000/ha. to 120 kg/ha/day of pelleted chicken manure was considered safe. Average fish production of 14 kg/ha/day resulted from using chicken manure, the pelleted manure supplemented with soybean and corn meals increased fish production to 22 kg/ha/day.

RECYCLING OF ANIMAL WASTES AS A SOURCE OF NUTRIENTS FOR FRESHWATER FISHCULTURE WITHIN AN INTEGRATED LIVESTOCK SYSTEM

see also:
Fish farming and the risk of spread of avian influenza (pdf file) by ornithologist Chris Feare.