Abstract
The present experiment investigated the effects of adding pig manure and chicken manure as supplementary feeds for rearing Sarotherodon mossambicus (Tilapia mossambica) in the laboratory.
The feeding test lasted for four weeks under stable aerated conditions. Various portions (10%, 40%, 60% w/w) of the two types of manure were mixed with dried tubifex worm pellets, whilst the control group consisted of tubifex worm alone. The metals studied were Mn, Fe, Cu and Pb.
The diets supplemented with 40% and 60% manure contained significantly (p < 0.05) greater amounts of all the metals tested except iron. The concentration of metals in the fish tissues (gill, viscera, flesh) was related to the amount of manure supplement. Harmful effects were reflected by significantly lower (p < 0.05) protein content in fish fed on manure-supplement diets, with the sole exception of the 10% pig manure supplement. Histological damage was also observed in the gills and the hepatopancreas of fish fed on diets supplemented with 60% pig manure and with 40% or 60% chicken manure.
Of the two kinds of animal manure investigated as potential supplementary feeds for rearing tilapia, the results indicate that pig manure is likely to be the better choice. Copyright © 1984 Published by Elsevier B.V.
The feeding test lasted for four weeks under stable aerated conditions. Various portions (10%, 40%, 60% w/w) of the two types of manure were mixed with dried tubifex worm pellets, whilst the control group consisted of tubifex worm alone. The metals studied were Mn, Fe, Cu and Pb.
The diets supplemented with 40% and 60% manure contained significantly (p < 0.05) greater amounts of all the metals tested except iron. The concentration of metals in the fish tissues (gill, viscera, flesh) was related to the amount of manure supplement. Harmful effects were reflected by significantly lower (p < 0.05) protein content in fish fed on manure-supplement diets, with the sole exception of the 10% pig manure supplement. Histological damage was also observed in the gills and the hepatopancreas of fish fed on diets supplemented with 60% pig manure and with 40% or 60% chicken manure.
Of the two kinds of animal manure investigated as potential supplementary feeds for rearing tilapia, the results indicate that pig manure is likely to be the better choice. Copyright © 1984 Published by Elsevier B.V.
| Original language | English |
|---|---|
| Pages (from-to) | 351-360 |
| Journal | Conservation & Recycling |
| Volume | 7 |
| Issue number | 2-4 |
| DOIs | |
| Publication status | Published - 1984 |