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