Table 10. List of commonly used manures for North African catfish Clarias gariepinus nursry ponds and their N:P ratio and NPK content
Type	N:P ratio and NPK content (%)
	N:P ratio	Nitrogen (N)	Phosphorus (P)	Potassium (K)
Cow dunga	3.41	1.91	0.56	1.40
Pig manure	2.06	2.8	1.36	1.18
Poultry manure	1.99	3.77	1.89	1.76
Duck manure	1.9	2.15	1.13	1.15
Source: Tacon (1987)