The presence of endogenous anti-nutritional factors within plant feedstuffs is believed to be the largest single factor limiting their use within compounded animal and fish feeds at high dietary levels. Table 11 summarizes the major groups of anti-nutritional factors present in plant feedstuffs with more specific examples given in Table 12. Although these factors vary in their individual toxicity to fish, a large proportion of them can be destroyed or inactivated by heat treatment processes (Tacon & Jackson, 1985).
Unfortunately toxicological studies have not been performed on the majority of these anti-nutritional factors; on a general basis however their presence in untreated foodstuffs normally results in anorexia, reduced growth and poor feed efficiency when used at high dietary concentrations. For review see NRC (1983), Hendricks & Bailey (1989) and Lovell (1989).
| PROTEINS | PROTEASE INHIBITORS HAEMAGGLUTININS |
|---|---|
| GLYCOSIDES | GOITROGENS CYANOGENS SAPONINS ESTROGENS |
| PHENOLS | GOSSYPOL TANNINS |
| MISCELLANEOUS | ANTI-MINERALS ANTI-VITAMINS ANTI-ENZYMES FOOD ALLERGENS MICROBIAL/PLANT CARCINOGENS TOXIC AMINO ACIDS |
| Feedstuff | Anti-nutritional factor 2 |
|---|---|
| CEREALS | |
| Barley (Hordeum vulgare) | 1,2,5,8 |
| Rice (Oryza sativum) | 1,2,5,8,13 |
| Sorghum (Sorghum bicolor) | 1,4,5,7,18 |
| Wheat (Triticum vulgare) | 1,2,5,8,11,18,22 |
| Corn/maize (Zea mays) | 1,5,8,19 |
| ROOT TUBERS | |
| Sweet potato (lpomoea batata) | 1,19 |
| Cassava (Manihot utilissima) | 1,4 |
| Potato (Solanum tuberosum) | 1,2,4,8,18,19 |
| LEGUMES | |
| Broad/faba bean (Vicia faba) | 1,2,5,7,22 |
| Chick pea/bengal gram (Cicer arietinum) | 1,4,5,8,11 |
| Cow pea (Vigna unguiculata) | 1,2,5,11 |
| Grass pea (Lathyrus sativus) | 1,9 |
| Haricot/kidney bean (Phaseolus vulgaris | 1,2,4,5,6,11,12,18 |
| Hyacinth/field bean (Dolichus lablab) | 1,2,4 |
| Lentil (Lens culinaris) | 1,2,6 |
| Lima bean (Phaseolus lunatus) | 1,2,4,5,7 |
| Lupin (Lupinus albus) | 1 |
| Mung bean/green gram (Phaseolus aureus) | 1,5,6,11,13 |
| Field pea (Pisum sativum) | 1,2,4,5,6,12 |
| Pigeon pea/red gram (Cajanus cajan) | 1,2,4,5 |
| Rice bean (Vigna umbellata) | 2 |
| Runner bean (Phaseolus coccineus) | 1,2 |
| Sword/jack bean (Canavalia gladiata) | 1,2,4,6 |
| Velvet bean (Stizobolium deeringianuum) | 1,22 |
| Winged bean (Psophocarpus tetragonolobus) | 1,2 |
| Carob bean (Ceratonia siliqua) | 1,7 |
| Guar bean (Cyamopsis psoraloides) | 1 |
| Alfalfa/lucerne (Medicago sativa) | 1,6,8,12 |
| Black gram (Phaseolus mungo) | 1,5 |
| lpil (Leucaena leucocephala) | 23 |
| OILSEEDS | |
| Groundnut (Arachis hypogaea) | 1,2,5,6,8 |
| Rapeseed (Brassica campestris napus) | 1,3,5,7 |
| Indian mustard (Brassica juncea) | 1,3,13 |
| Soybean (Glycine max) | 1–3,5,6,8,11,12,14,16,17 |
| Sunflower (Helianthus annuus) | 1,7,20 |
| Cottonseed (Gossypium spp.) | 5,8,10,12,24 |
| Linseed (Linum usitatissimum) | 4,8,13,15 |
| Sesame (Sesamum indicum) | 5 |
| Crambe (Crambe abyssinica) | 3 |
1 Compiled from the data of Kay (1979) and Liener (1980)
2 1-Protease inhibitor,
2-Phytohaemagglutinins,
3-Glucosinolates,
4-Cyanogens,
5-Phytic acid,
6-Saponins,
7-Tannins,
8-Estrogenic factors,
9-Lathyrogens,
10-Gossypol [a dietary level of 0.05% free gossypol suppresses growth and severelyreduces blood haematocrit and haemoglobin in rainbow trout, a minimum of0.03% causes growth depression, and 0.009% causes histological liver changes,including necrosis and ceroid deposition (Herman, 1970). By contrast, dietarygossypol levels of up to 0.18% were reported to be tolerated by Tilapia aureawithout growth reduction (Robinson, Rawles & Stickney, 1984). However,according to Lovell (1989) the addition of 0.85 to 1.0 part of ferrous sulphate toeach part of free gossypol in the diet of pigs and poultry has proven successful inblocking the toxic effects of gossypol],
11-Flatulence factor,
12-Anti-vitamin Efactor,
13-Anti-thiamine factor,
14-Anti-vitamin A factor,
15-Anti-pyridoxinefactor,
16-Anti-vitamin D factor,
17-Anti-vitamin B12 facto
18-Amylaseinhibitor,
19-Invertase inhibitor,
20-Arginase inhibitor,
21-Cholinesterase inhibitor,
22-Dihydroxyphenylalanine,
23-Mimosine,
24-Cyclopropenoic acid
