Table 4. Summary of dietary nutrient requirements of North African catfish Clarias gariepinus (requirement expressed for dry feed except where otherwise  mentioned)
Nutrients		Nutrient levels
		Life stage/size class
		Larval rearing	Nursery phase	Grow out		References
		12�14 d	0.5�10 g	10�1 000 g
Protein and amino acids
Crude protein, % min		55 1	50 e,20	40-42 2, 40 3,24 43 2,4,6,16,17,25,26		1,2,3,4,6,16,17,20,24,25,26
Least costed and or appetite feeding protein requirement				35 16, 38 2		2,16
Amino acids, % min of dietary protein
Arginine			4.5 6, 4.45-4.50 c,19			6,19
Histidine			1.0�1.05 5	1.39 17		5,17
Isoleucine				1.56 17		17
Leucine				4.87 17		17
Lysine			5.7 9	4.49 17		9,17
Methionine		2.5 1		3.2 8		1, 8
Phenylalanine				4.56 17		17
Threonine				2.04 17		17
Tryptophan			1.1 7	2.59 17		7,17
Valine				2.08 17		17
Lipid and fatty acids
Crude lipid, % min		9 1�		8.2 15, 10�12 2,11.5 3,13 16,10�17 17		1,2,3,15,16,17
Essential fatty acids, % min
18:2n-6
20:4n-6
18:3n-3
20:5n-3
22:6n-3
n-3 : n-6 ratio		1:1 1				1
Carbohydrate, % recommended		21 1		15�35 2,10,11, 12,15,16,  26-32 17		1,2,10,11,12,15,16,17
Energy
Digestible energy, min kJ/g				14�16 2, 12.7 3, 21		2,3, 21
Metabolizable energy, min kJ/g				13 3�		3
Gross energy, min kJ/g				11�13 4, 21 3,  21.2 15,  22-24 17		3,4,15,17
Protein to energy ratio, mg/kJ				20.5 15, 26�29 2, 31 3, 31�36 4, 21.5�23 17		2,3,4,15,17
Lipid to carbohydrate ratio (g/g)				2.47(lipid 13%, carbohydrate 33.42%) 16		16
Mineralsa
Macroelements (%)
Calcium			0.45 18	1.5 2		2,18
Phosphorus			0.45 18	0.5 2		2,18
Magnesium			0.04 18			18
Sodium
Potassium			0.26 18			18
Microelements, mg/kg dry diet
Iron			30 18			18
Sulphur
Chlorine
Copper			5 18			18
Manganese			≤2.40 18			18
Zinc			20 18			18
Cobalt
Selenium			0.25 18			18
Iodine
Molybdenium
Chromium
Flourine
Vitaminsa
Vitamin A IU/kg			1 000�2 000 18			18
Vitamin D IU/kg			500�1000 18			18
Vitamin E min mg/kg			25�50 18			18
Thiamine min mg/kg			1 18			18
Riboflavin min mg/kg			9 18			18
Pyridoxine min mg/kg			3 18			18
Pantothenic acid min mg/kg			10�15 18			18
Niacin min mg/kg			33.1 23			23
Folic acid min mg/kg			1.2 18			18
Choline min mg/kg			400 18			18
Biotin b min mg/kg				2.49 13		13
Ascorbic acid min mg/kg		150 14, 500 23	11�60 18, 50 22			14,18,22,23
Notes:
a	Mineral and vitamin requirements are generally assumed to be the same as for Ictalurus punctatus.
b	Biotin requirement determined for Clarias batrachus.
c	For hybrids between Clarias gariepinus and C. macrocephalus.
e	For hybrids between Clarias gariepinus and Heterobranchus bidorsalis.
Source:
1	Uys and Hecht (1985)
2	Uys (1989)
3	Machiels and Henken (1985)
4	Degani, Ben-Zvi and Levanon (1989)
5	Khan and Abidi, (2009)
6	Fagbenro, Nwanna and Adebayo (1999)
7	Fagbenro and Nwanna (1999)
8	Fagbenro, Balogun and Fasakin (1998)
9	Fagbenro et al. (1998)�
10	Balogun and Ologhobo (1989)
11	Heinsbroek, Van Thoor and Elizondo (1990)
12	Fagbenro et al. (1993)
13	Mohamed, Ravisankar and Ibrahim (2004)
14	Merchie et al. (1997)
15	Ali and Jauncey (2005a)
16	Ali (2001)
17	Pantazis (1999)
18	Wilson and Moreau (1996)
19	Singh and Khan (2007)
20	Adebayo and Alasoadura (2001)
21	Yilmaz et al. (2006)
22	Adewolu and Aro (2009)
23	Kuczynski (2002)
24	Machiels and Henken (1987)
25	Ali and Jauncey (2005b)
26	Ali and Jauncey (2005c)