Previous Page Table of Contents Next Page


4.3 Anti-nutritive and Toxic Factors in Forage Tree Legumes

B.W. Norton


Introduction
Screening Techniques for Plant Toxins
Secondary Plant Compounds in Forage Tree Legumes
Conclusions
References


Introduction

Plants have co-evolved with predator populations of bacteria, insects, fungi and grazing animals, and have developed defence mechanisms which assist their survival. Leguminous trees and shrubs often have thorns, fibrous foliage and growth habits which protect the crown of the tree from defoliation. Many plants also produce chemicals which are not directly involved in the process of plant growth (secondary compounds), but act as deterrents to insect and fungal attack. These compounds also affect animals (including humans) and the nutritive value of forages. Mycotoxins (fungal metabolites) produced by saprophytic and endophytic fungi are also a potential source of toxins in forages.

The effects of both secondary metabolites and mycotoxins vary with animal species. Non-ruminants (e.g. pigs, poultry and horses) are usually more susceptible to toxicity than ruminants which have the capacity to denature potential toxins in the rumen. The nature and action of toxins in plants have been the subject of several reviews (Duke 1977, Rosenthal and Janzen 1979, Hegarty 1982, Seawright et al. 1985, Barry and Blaney 1987), in which attention was focused on pasture plants of commercial importance.

This section reviews the information available on the anti-nutritive and toxic compounds which have been found in forage tree legumes.

Screening Techniques for Plant Toxins

In plant introduction and range evaluation programmes, there is a need to rapidly screen large numbers of plants for nutritive value, palatability and potential toxicity. Since it is usually not feasible to collect sufficient herbage to feed ruminants, alternative techniques have been developed using laboratory animals (e.g. mice, rats, rabbits and guinea pigs) as test animals. Rats have been used to detect a wide range of plant toxins potentially harmful to man and other monogastric animals. Since the rat is more sensitive to plant toxins than ruminants, several workers have used a rat bioassay to test the presence of toxins in tropical pasture legumes (Bindon and Lamond 1966, Strickland et al. 1987). Although toxicity to rats is not necessarily indicative of similar problems in ruminants, the process allows rapid identification of potentially toxic species which can then be investigated further in feeding trials with ruminants. The results of these bioassays will be discussed in this section. With the increasing interest in tree legume species, there is a need to extend these trials to a wider range of species.

Secondary Plant Compounds in Forage Tree Legumes

Secondary plant compounds may produce toxic effects in ruminant animals (e.g. cyanide, nitrate and fluoroacetate), may depress intake and/or utilisation of feed components (mycotoxins, high tannins), or may enhance feed nutritive value (low tannins, anti-protozoa! activity). Table 4.3.1 provides a summary of the compounds which have been found in tree legume species which may affect animal productivity. The list of species and compounds is not exhaustive, and some compounds listed may not be toxic. Although mycotoxins in forages are known to cause some commercially important toxicoses in grazing stock (e.g. ryegrass staggers, lupinosis and facial eczema), no comparable reports can be found for stock consuming tree species.

The mode of action of some of the compounds (tannins, cyanogenic glycosides and saponins) has been described in detail by other reviewers and will not be attempted here. In the following section, the significance of these compounds to the nutritive value of the major tree legume species will be discussed.

Acacia

Mulga (Acacia aneura) is the most common Acacia species used for stock feeding in Australia. As mentioned in Section 4.2, mulga is of low nutritive value. Many acacias have high concentrations of phenolic compounds in their leaves, the major compounds being lignin and tannins. The tannins may be further categorised into hydrolysable tannins (polyesters of garlic acid and hexahydroxyphenic acid derivatives) and condensed tannins (proanthocyanidins). In ruminants, the ingestion of hydrolysable tannins can cause death, but these animals have a higher tolerance of condensed tannins. The condensed tannins in mulga inhibit plant protein degradation in the rumen and decrease rumen availability of sulphur, which then depresses the digestibility of plant cell walls. It is also possible that these tannins inhibit microbial enzymes in the rumen and decrease the availability of plant proteins for digestion in the intestines.

Table 4.3.1. A list of secondary compounds found in some forage tree legume species.

Species

Plant part

Compound

Reference

Acacia aneura

leaf

condensed tannins, oxalate

1

Acacia cambagei




leaf

cyanogenic glycoside (CG)

2


CG hydrolase



oxalate


bark



Acacia cana

leaf, stem

selenium

2

Acacia doratoxylon

leaf, stem

CG

2

Acacia georgina


leaf, stem

CG hydrolase (no CG)

2


fluoroacetate

2

Acacia salicina


leaf, bark

tannins

3

pods

saponins

4

Albizia chinensis




bark

echinocystic acid

5


glycosides, oleanolic acid



sterols


leaf

condensed tannins

6

Albizia lebbeck



flowers

various sterols

7

leaf

pipecolic add derivatives

8

root

echinocystic acid

9

Calliandra calothyrsus

leaf

condensed tannins

6

Calliandra haematocephala

leaf

pipecolic acid derivative

10

Calliandra portoricensis


leaf

tannins, saponins, flavonoids,

11


glycosides


Gliricidia sepium





leaf

pinitol

12

leaf

condensed tannins

6

leaf

coumarins, melilotic add

13

leaf

CG, nitrate

14

seed

canavanine, heat stable toxin

9

Leucaena leucocephala



leaf

mimosine

15

leaf

condensed tannins

6

leaf

flavanol glycosides

16

Sesbania grandiflora


leaf, seed

condensed tannins, glycosides

17

flowers

methyl oleanolate

18

Sesbania sesban



leaf

saponin
(glucuronide-oleanolic acid)

19

leaf

saponin, heat labile toxin

20

seed

saponin
(stigmasta galactopyranoside)

21

* References: 1. Gartner and Hurwood (1976); 2. Cunningham et al. (1981); 3. Everist (1969); 4. Hall et al. (1972); 5. Rawat et al. (1989); 6. Ahn et al. (1989); 7. Asif et al. (1986); 8. Romeo (1984); 9. Sotelo et al. (1986); 10. Marlier et al. (1979); 11. Aguwa and Lawal (1987); 12. Calle et al. (1987); 13. Griffiths (1962); 14. Manidool (1985); 15. Hegarty et al. (1964); 16. Lowry et al. (1984); 17. Andal and Sulochana (1986); 18. Kalyanaguranathan et al. (1985); 19. Dorsaz et al. (1988); 20. Shqueir et al. (1989); 21. Kholi (1988)

Tannins do not appear to be present in all Acacia species, and perhaps low tannin species could be selected for further study. Tannins may also be associated with the poor acceptability of young mulga leaves, although volatile oil content is also highest in young leaf (Melville 1947). There is recent evidence that some ruminal microorganisms are able to metabolise tannins, or able to remain active in a high tannin environment, and may be used as inoculants to overcome the detrimental effects of tannins in ruminants (Section 4.6).

Mulga also contains sufficient insoluble oxalate to affect the availability of calcium (Gartner and Hurwood 1976). Where oxalate concentrations are high, calcium oxalate crystals may be formed in the kidney leading to urolithiasis. However, given time to adapt, the microorganisms in the rumen can metabolise moderate amounts of oxalate, and there is little reason to suspect that oxalate poisoning is a serious problem when feeding mulga.

Cyanogenic glycosides (CG) occur in many Acacia species and, when ingested and hydrolysed to free hydrogen cynanide (HCN), cause cyanide toxicity. Cynanide combines with haemoglobin in blood and inhibits respiratory enzymes, ultimately causing death. The response of ruminants to CG ingestion varies. In the rumen, HCN is converted to thiocyanate using available sulphur and thiocyanate is absorbed and excreted. Thiocyanate is a goitrogen, inhibiting the activity of the thyroid gland, and often the effect of CG ingestion is seen as the development of goitre (thyroxine or iodine deficiency). Iodine supplementation overcomes this effect. The ruminal trapping of sulphur may also induce a sulphur deficiency which can be corrected by supplemental sulphur (Wheeler et al. 1975). The formation of HCN from this glycoside requires the presence of a specific hydrolytic enzyme in the plant tissue. Table 4.3.1 shows that both enzymes are not always present and, in the absence of the hydrolytic enzyme, CG are not toxic.

The seeds and pods of Georgina gidyea (Acacia georgina) contain fluoroacetic acid (FA), an organic acid found in a range of other plants (e.g. Dichapetalum, Gastrolobium and Spondanthius). This compound inhibits the Krebs cycle by formation of fluorocitrate and is used as a poison for rats and rabbits. FA and its derivatives are also used as insecticides. Fluorine is a cumulative poison, and its effects are often observed only after stock have been grazing plants containing these compounds for a significant time. When compared with other FA containing plants, G. gidyea has only low concentrations, and FA poisoning is only a problem when the plant is the sole source of food during a drought. It is of some interest that native Australian mammals (e.g. kangaroos and possums) normally consume the seeds of G. gidyea with impunity, suggesting that these species have developed a mechanism for tolerance of toxicity (Twigg et al. 1986).

Albizia

Albizia lebbeck or Indian siris has been more intensively studied than the faster growing A. chinensis. A major difference between the species is in tannin content. Albizia chinensis contains significant levels of condensed tannins and proanthocyanidins while A. lebbeck contains no extractable tannins (Ahn et al. 1989). Green leaf, fallen leaf and flowers of A. lebbeck have all been shown to be highly palatable and of high nutritive value for sheep (Lowry 1989). Less is known about A. chinensis although it is readily accepted (either fresh or dried) by young goats as a supplement to low quality straws (Robertson 1988, Ash 1990) and is eagerly browsed by does and their kids.

A variety of secondary compounds have been isolated from Albizia species, some having biological activity. A range of sterols (taxerol, cycloartemol, lupeol, campesterol and sitosterol) have been found in the flowers of A. lebbeck (Asif et al. 1986) and a saponin (echinocystic acid) was reported in root extracts (Shrivastava and Saxena 1988). Saponins are glycosides of steroid or triterpenoid compounds (e.g. ursane, oleanane and lupane) and, by their detergent action, have been implicated in the formation of bloat in cattle grazing white clover pastures. Triterpenic substances and glycosides of echinocystic acid (saponin) have been isolated from the bark of A. chinensis, and these bark extracts have been found to have molluscicidal (Ayoub and Yankov 1986), spermacidal (Rawat et al. 1989) and insecticidal (Tripathi and Rizvi 1985) properties. Rahman et al. (1986) also reported that alkaloids from the seeds of A. lebbeck are fungicidal and cytotoxic to selected lines of cancer cells growing in vitro. As the name suggests, the neutral non-protein amino acid albizzine was first isolated from Albizia lebbeck, but no toxic activity has been reported.

Whilst these compounds may provide some protection against plant predators, they do not appear to affect the palatability and intake of forage trees by ruminants. It has been observed that whilst goats will eat the bark of some browse trees, little bark damage is found when goats browse A. chinensis. The high content of saponins in bark may be deterring consumption. There appear to be no reports of saponins in Albizia leaf and the dried leaf is non-toxic when fed to rats (Ahn 1990). Although there is a paucity of information on the effects of A. chinensis fed to ruminants, it appears that Albizia species may prove to be a valuable new source of forage for ruminants.

Calliandra

All Calliandra species appear to contain condensed tannins, with high levels (>10%) in C. calothyrsus. When fed to rats (20% of diet), feed intake (palatability) was high but all rats lost weight (Ahn 1990). Tannins are known to have a direct effect on metabolism. Chickens fed high tannin sorghums develop leg abnormalities (Elkins et al. 1978). Barry et al. (1986) found that plasma growth hormone levels increased with increased intake of condensed tannins by sheep. Tannins react not only with dietary protein but also with enzymes of the gut wall and protein in saliva

Ruminants appear to be more tolerant of tannins than non-ruminants, although few studies have been conducted with forage tree legumes. Palmer and Schlink (1992) have reported that wilting (25°C for 24 h) Calliandra calothyrsus (calliandra) depressed feed intake in sheep when given a sole diet over an 8 day period. Ahn et al. (1989) have shown that drying decreases extractable tannin content of tree legumes, including Calliandra. Table 4.3.2 shows the results from an experiment where frozen (fresh) and dried calliandra were fed as supplements to sheep given a low quality (barley straw) diet. The removal of tannins by polyethylene glycol (PEG) infusion resulted in an increased consumption of straw when frozen calliandra was fed. Drying alone increased straw intake and the digestibility of the cell walls (NDF). PEG infusion increased the digestibility of N. particularly in the rumen, which resulted in higher urinary N losses as ammonia. It was concluded from this study that the presence of both tannins and a heat labile compound in fresh calliandra depresses feed utilisation, and that drying removes a factor (not tannin) which is depressing the digestibility (and intake) of barley straw by these sheep. The nature of this factor is not known, and clearly deserves further study. At the level of feeding used in this study, drying effectively removed the detrimental effect of both tannins and the unknown heat labile factor. There is a need to confirm these effects at higher levels of forage intake, and to reconcile these positive effects of drying with the negative effects found by Palmer and Schlink (1992).

Although there are no reports of secondary compounds in C. calothyrsus, the leaves of C. portoricensis were found to contain saponins, flavonoids and glycosides (Aguwa and Lawal 1987). These extracts have bactericidal (Adensina and Akinwusi 1984, Aguwa and Lawal 1987) and helminthicidal properties in dogs (Adewuni and Akubue 1981). Pipecolic acid, a non-protein amino acid, and its derivatives have been isolated from the leaves of C. haematocephala (Marker et al. 1979) and these compounds were shown to have insecticidal properties (Romeo 1984). The effects of these compounds on sheep is not known, but it does seem possible that some may be useful as stock and human medicines.

Gliricidia

There is varying opinion about the nutritive value of Gliricidia sepium (gliricidia). It is generally agreed that it is a high quality forage, but of low palatability when first introduced to animals. Carew (1983) found that gliricidia in the diet of sheep and goats induced diarrhoea and depressed consumption of dried leaves during the first 3 weeks of feeding. Similar observations were made by Robertson (1988) where goats took 5 days to adapt to prescribed intakes of fresh and dried gliricidia leaves. The odour of the leaves has been implicated in this initial reluctance of animals to eat gliricidia (Brewbaker 1986). However, once adapted, there appear to be no long-term detrimental effects on sheep and cattle (Chadhokar 1982). The composition and quality of milk of dairy cows given 30% of their diet as fresh gliricidia leaves was not affected (Chadhokar 1982).

Table 4.3.2. The effects of drying Calliandra calothyrsus and infusion of polyethylene glycol (PEG) on dry matter and N utilisation in sheep given barley straw diets supplemented with Calliandra (adapted from Ahn 1990).

Component

Frozen

Oven-dried


-PEG

+PEG

-PEG

+PEG

Intake (g/day)


Tannins

17.7a*

17.7a

14.6b

14.6b


Barley straw

624.0a

761.0b

721.0b

742.0b


Calliandra

180.0

180.0

189.0

189.0


Total

804.0a

941.0b

910.0b

931.0b

Digestibility (%)


Dry matter

39.9

39.6

46.3

44.1


NDF

39.3a

40.6a

49.0b

46.5b


Nitrogen (N)

20.7a

39.2b

31.6c

43.4b

N utilisation (g/day)


N intake

10.2

10.9

10.7

10.8


N in faeces

8.1a

6.6b

7.4c

6.1b


N in urine

4.0a

5.9b

3.9a

5.4b


N balance

-1.9

-1.6

-0.5

-1.1

* Values within a line with different subscripts differ significantly (P < 0.06)

The tannin content of gliricidia leaves does not appear to interfere with plant protein availability but may be one of the factors affecting palatability (Table 4.3.3). Ahn (1990) found that drying removed all extractable tannins from gliricidia increased straw intake, dry matter and N digestibility and N balance in sheep. However, it is not possible to decide whether these effects were due to the tannins or some other factor removed or inactivated during drying. Even though drying removed tannins and improved nutritive value, sheep still consumed gliricidia with reluctance, suggesting that the factor(s) associated with poor palatability were not removed by drying.

The factors affecting palatability of gliricidia in ruminants are probably the same as those that depress digestibility and growth in rabbits and chickens given gliricidia leaf meal diets (Raharjo and Cheeke 1985). Gliricidia and calliandra were the least palatable of the forages offered in this study. Ahn (1990) also found depressed intakes, weight loss and foetal deaths in rats offered a diet containing 20% dried gliricidia leaf. Gliricidia bark and seeds are reported to be used as a rat poison in some countries (Sotelo et al. 1986) suggesting that a toxic principle is present. Coumarins have been found in gliricidia leaf (Table 4.3.1); these compounds are precursors of phyto-oestrogens which have caused infertility and abortion in sheep grazing clover in Australia (Cox and Braden 1974). However, Chadhokar (1982) fed diets containing 75% gliricidia to pregnant sheep and found only beneficial effects of supplementation. Sotelo et al. (1986) have reported a thermostable toxin in gliricidia seeds which killed mice within l week of feeding. These authors isolated a non-protein amino acid, canavanine (2-amino-4-guanidooxy-butyric acid) from gliricidia seeds, and this compound may be associated with the toxicity of gliricidia in non-ruminants. However, many of these reports require confirmation by further experimentation. Nevertheless, despite the problem with palatability in ruminants, the undoubted value of gliricidia as a source of forage makes continued study of this species still worthwhile.

Leucaena

The value of Leucaena leucocephala (leucaena) as a feed for stock has been documented by many workers even though all parts of the plant contain the non-protein amino acid mimosine (b -[N-(3-hydroxy-4-oxopyridyl)]-a -aminopropionic acid) which is highly toxic to non-ruminants. Mimosine acts by interfering in cellular mitosis, and the symptoms of toxicity are alopecia, reduced appetite, reduced weight gain and often death. It is recommended that diets for pigs and poultry should contain less than 10% leucaena.

It is now known that in areas where leucaena is indigenous (Central America), and in parts of Asia, ruminants consuming leucaena appear able to degrade the ruminal metabolite of mimosine, 3-hydroxy-4(1H)-pyridone (DHP), to harmless end-products (Jones and Lowry 1984). This capacity is associated with a specific bacterial population in the rumen of these adapted animals. However, where leucaena has been introduced to ruminant populations without this adaptation, symptoms of toxicity such as alopecia, excessive salivation, lack of coordination of gait, enlarged thyroid glands (low serum thyroxine) and reduced fertility are often observed (Jones 1979). These symptoms have been reported in Papua New Guinea (Holmes et al. 1981) Australia (Hegarty et al. 1976) and can be expected in other areas of the tropics where leucaena has been newly introduced.

Toxicity in ruminants is caused by DHP, which is a potent goitrogen. The severity of toxicity is related to the level of leucaena consumed, and diets containing less than 30% are generally considered safe for ruminants. Alternatively, ruminal organisms capable of degrading DHP may be introduced into the rumen of stock grazing leucaena (Jones and Megarrity 1986), thereby removing this restraint to increased use of leucaena. The management strategies needed to maximise animal productivity from leucaena are reported in Section 4.5.

Table 4.3.3. The effects of drying supplemental Gliricidia and Calliandra leaf on the intake and utilisation of barley straw by sheep (adapted from Ahn 1990).

Component


Gliricidia

Calliandra

Fresh

Dried

Fresh

Dried

(a) Intake (g/day)


Tannins

4.0

0.0

23.8

16.4


Barley straw

392.0a*

680.0b

436.0a

691.0b


Tree forage

200.0

200.0

204.0

200.0


Total

593.0a

880.0b

640.0a

891.0b

(b) Digestibility (%)


Dry matter

42.3a

60.5b

36.3a

59.0b


Nitrogen

24.6a

47.4b

7.3c

39.9d

(c) N utilisation (g/day)


N intake

8.3a

8.5a

9.2b

9.7b


N in faeces

6.3a

4.5b

8.6

5.8a


N in urine

2.9

2.6

2.4

1.4


N balance

-0.9a

1.4b

-1.7a

2.5b

* Values with a line with different subscripts differ significantly (P < 0.06)

Sesbania

Two species of Sesbania are potentially useful forage sources - the slower growing tree S. grandiflora and the rapidly growing short-lived species S. sesban. Sesbania grandiflora leaves and pods are reported to be palatable and non-toxic for cattle (NAS 1979). Some other reports suggest that the white flowering variety is non-toxic, while the purple flowering type is toxic (Hutagalung 1981). Dried leaves of S. grandiflora have been fed (20% of diet) to milking cows (Tendulkar et al. 1984) and goats (15% of diet) without detrimental effects (van Eys et al. 1985, Ash 1990). Sesbania sesban has also been successfully fed as a sole diet to goats (Singh et al. 1980) and as a supplement to low quality forage for young sheep (Reed and Soller 1987). In this latter study, S. sesban (50% dry matter) was fed for 91 days, during which time the sheep grew at a rate of 48 g/day.

A major difference between the species is that S. grandiflora contains condensed tannin precursors (cyanidins) in leaves, whilst no tannin can be detected in S. sesban. However, both species contain compounds potentially toxic to non-ruminants. The methyl ester of oleanolic acid has been isolated from the flowers of S. grandiflora and shown to have haemolytic effects on sheep and human erythrocytes (Kalyanaguranathan et al. 1985). Olvera et al. (1988) found poor growth and high mortality in Tilapia fingerlings at all levels of inclusion (10-35%) of S. grandiflora leaf meal in a fish meal diet. Similar results were obtained when leaf meal of S. grandiflora was substituted in starter rations for chickens (A. Ash, personal communication).

Oil from the seeds of S. sesban is accorded specie properties in Ayurvedic medicine, and is reported to have bactericidal, cardiac depressant and hypoglycaemic actions. The saponin, stigmasta-galactopyranoside has recently been isolated from S. sesban seeds (Kholi 1988). Dorsaz et al. (1988) have isolated glucuronide derivatives of oleanolic acid which has molluscicidal activity against Biophalaria glabrata, one of the known snail vectors of schistosomiasis. This saponin also showed spermicidal and haemolytic activity. Tripathi and Rizvi (1985) also found that S. sesban extracts had anti-feeding activity against moth larvae. Shqueir et al. (1989) found that the inclusion of S. sesban leaf meal in poultry diets (10% of diet) proved fate. to young chicks, and that the provision of either cholesterol or sitosterol with the diet significantly improved survival. The authors reported that the leaves contain a saponin-like toxin and a heat labile factor. It is clear from these studies that both Sesbania species contain a number of toxins with specific activity against a variety of organisms.

Although no reports of acute toxicity in ruminants were found, many of these trials were of limited duration. In grazing studies with goats in Australia, goats showed a high preference for the bark of S. sesban, even when sufficient leaf was available, killing many trees. No toxic effects were found in goats consuming this bark. It has been observed that the bark of S. sesban accessions may be either green or red, and goats readily consumed green bark. It is not known whether goats have the same preference for the red-barked variety, or whether the colour is indicative of compounds detrimental to ruminants. This aspect of grazing behaviour needs further study. In a year-long field grazing study at the University of Queensland, heifer cattle were initially reluctant to browse S. sesban. However, after 3 months they began to consume Sesbania selectively and their weight gains dramatically improved with no indication of toxicity (Gutteridge and Shelton 1991).

Conclusions

Although many different, and some potentially dangerous, compounds have been isolated from many of the potentially useful forage legume trees, little is known about the specific effects of these compounds on ruminant metabolism. The intense interest in leucaena has generated research which firstly identified the regional problem of mimosine and DHP toxicity, and then proceeded to provide a practical solution to the management of this problem. A newer set of forage trees is now available and is being agronomically evaluated. Their nutritive value needs to be intensively studied before they can be released for widespread use.

References

Adensina, S.K. and Akinwusi, D.D. (1984) Biological effects of Calliandra portoricensis and Lagenaria brevifolia extracts. Fitoterapia 55, 339-342.

Adewuni, C.O. and Akubue, P.I. (1981) Preliminary studies on the antihelminthic properties of aqueous extract of Calliandra portoricensis (Jacq.) Benth. Bulletin of Animal Health and Production in Africa 29, 172-175.

Aguwa, C.N. and Lawal, A.M. (1987) Pharmacologic studies on the active principles of Calliandra portoricensis leaf extracts. Journal of Ethnopharmacology 22, 63-71.

Ahn, J.H. (1990) Quality assessment of tropical browse legumes: tannin content and nitrogen degradability. PhD thesis, The University of Queensland.

Ahn, J.H., Robertson, B.M., Elliott, R., Gutteridge, R.C. and Ford, C.W. (1989) Quality assessment of tropical browse legumes: tannin content and protein degradation. Animal Feed Science and Technology 27, 147-156.

Andal, K.R. and Sulochana, N. (1986) Chemical examination of the seeds of Sesbania grandiflora. Fitoterapia 57, 293-294.

Ash, A.J. (1990) The effect of supplementation with leaves from the leguminous trees Sesbania grandiflora, Albizia chinensis and Gliricidia sepium on the intake and digestibility of Guinea grass hay by goats. Animal Feed Science and Technology 28, 225-232.

Asif, M., Mannan, A., Itoh, T. and Matsumoto, T. (1986) Analysis of Albizia flower oil. Fette Seifen Anstrichmittel 88, 180-182.

Ayoub, S.M.H. and Yankov, L.K. (1986) The molluscicidal factor of tannin-bearing plants. International Journal of Crude Drug Research 24, 16-18.

Barry, T.N. and Blaney, B.J. (1987) Secondary compounds of forages. In: Hacker, J.B. and Ternouth, J.H. (eds), The Nutrition of Herbivores, Academic Press, Sydney, pp. 91-120.

Barry, T.N., Allsop T.F. and Redekopp, C. (1986) The role of condensed tannins in the nutritional value of Lotus pedunculatus. 5. Effects on the endocrine system and on adipose tissue metabolism. British Journal of Nutrition 56, 607-614.

Bindon, B.M. and Lamond, D.R. (1966) Examination of tropical legumes for deleterious effects on animal reproduction. Proceedings of the Australian Society of Animal Production 6, 109-116.

Brewbaker, J.L. (1986) Leguminous trees and shrubs for Southeast Asia and South Pacific. In: Blair, G.J., Ivory, D.A. and Evans, T.R. (eds), Forages in Southeast Asia and South Pacific Agriculture. Proceedings of a workshop held at Cisarua, Indonesia. ACIAR Proceedings No. 12. ACIAR, Canberra, pp. 43-50.

Calle, J., Rivera, A. and Joseph-Nathan, P. (1987) Pinitol from the leaves of Gliricidia sepium. Planta Medica 53, 303.

Carew, B.A.R. (1983) Gliricidia sepium as a sole feed for small ruminants. Tropical Grasslands 17, 181-184.

Chadhokar, P.A. (1982) Gliricidia maculata: a promising legume fodder plant. World Animal Review 44, 36-43.

Cox, R.I. and Braden, A.W. (1974) The metabolism and physiological effects of phytooestrogens. Proceedings of the Australian Society of Animal Production 10, 122-129.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1981) Plants of Western New South Wales. NSW Government Printing Office, Sydney.

Dorsaz, A.C., Hostettmann, M. and Hostettmann, K. (1988) Molluscicidal saponins from Sesbania sesban. Planta Medica 54, 225-227.

Duke, J.A. (1977) Phytotoxin tables. CRC Critical Reviews in Toxicology 5, 189-237.

Elkins, R.G., Featherston, W.R. and Rogler, J.C. (1978) Investigations of leg abnormalities in chicks consuming high tannin sorghum grain diets. Poultry Science 57, 757-762.

Everist, S.L. (1969) Use of fodder tress and shrubs. Queensland Department of Primary Industry Advisory Leaflet No. 1024.

Gartner, R.W.J. and Hurwood, I.S. (1976) The tannin and oxalic acid content of Acacia aneura (mulga) and their possible effects on sulphur and calcium availability. Australian Veterinary Journal 52, 194-196.

Griffiths, L.A. (1962) On the co-occurrence of coumarin, O-coumaric acid and melilotic acid in Gliricidia sepium. Journal of Experimental Botany 13, 169-175.

Gutteridge, R.C. and Shelton, H.M. (1991) Evaluation of Sesbania sesban - a new forage shrub species for tropical and subtropical Australia. Final Technical Report, Meat Research Corporation, Canberra, 12 pp.

Hall, N., Boden, R., Christian, C.S., Condon, R., Dale, F., Hart, A., Leigh, J., Marshall, J., McArthur, A., Russel, V. and Turnbull, J. (1972) The Use of Trees and Shrubs in the Dry Country of Australia. Australian Government Public Service, Canberra, 558 pp.

Hegarty, M.P. (1982) Deleterious factors in forages affecting animal production. In: Hacker, J.B. (ed.), Nutritional Limits to Animal Production from Pastures. CAB, Farnham Royal, UK, pp. 133-150.

Hegarty, M.P., Schinckel, P.G. and Court, R.D. (1964) Reaction of sheep to the consumption of Leucaena glauca and to its toxic principle mimosine. Australian Journal of Agricultural Research 15, 153-167.

Hegarty, M.P., Court, R.D., Christie, G.S. and Lee, C.P. (1976) Mimosine in Leucaena leucocephala is metabolised to a goitrogen in ruminants. Australian Veterinary Journal 52, 490-496.

Holmes, J.H.G., Humphrey, J.D., Walton, E.A. and O'Shea, J.D. (1981) Cataracts, goitre and infertility in cattle grazed on an exclusive diet of Leucaena leucocephala. Australian Veterinary Journal 57, 257-260.

Hutagalung, R.I. (1981) The use of tree crops and their byproducts for intensive animal production. In: Smith, A.J. and Gunn, R.G. (eds), Intensive Animal Production in Developing Countries. Occasional Publication No. 4, British Society of Animal Production, pp. 151-184.

Jones, RJ. (1979) The value of Leucaena leucocephala as a feed for ruminants in the tropics. World Animal Review 31, 13-23.

Jones, R.J. and Lowry, J.B. (1984) Australian goats detoxify the goitrogen 3 hydroxy-4(1H) pyridone (DHP) after ruminal infusion from an Indonesian goat. Experientia 40, 1435-1436.

Jones, R.J. and Megarrity, R.G. (1986) Successful transfer of DHP-degrading bacteria from Hawaiian goats to Australian ruminants to overcome the toxicity of leucaena. Australian Veterinary Journal 63, 259-262.

Kalyanaguranathan, P., Sulchana, N. and Murugesh, N. (1985) In vitro haemolytic effect of the flowers of Sesbania grandiflora. Fitoterapia 56, 188-189.

Kholi, D.V. (1988) A new saponin, Stigmasta-5,24(28)-diene-3beta-O-beta-D-galactopyranoside from the seeds of Sesbania sesban. Fitoterapia 59, 478-479.

Lowry, J.B. (1989) Agronomy and forage quality of Albizia lebbeck in the semi-arid tropics. Tropical Grasslands 23, 84-91.

Lowry, J.B., Cook, N. and Wilson, R.D. (1984) Flavonol glycosides distribution in cultivars and hybrids of Leucaena leucocephala. Journal of the Science of Food and Agriculture 35, 401-407.

Manidool, C. (1985) Utilization of tree legumes with crop residues as animal feeds in Thailand. In: Relevance of Crop Residues as Animal Feeds in Developing Countries. Proceedings of an international workshop, Khon Kaen, Thailand, pp. 249-269.

Marlier, M., Dardenne, G. and Casimir, J. (1979) 2S, 4R-carboxy-2-acetylamino-4-piperidine in the leaves of Calliandra haematocephala. Phytochemistry 18, 479-481.

Melville, G.F. (1947) An investigation of the drought pastures of the Murchison district of Western Australia. Journal of Department of Agriculture of Western Australia 24, 1-29.

NAS (1979) Tropical Legumes: Resources for the Future. National Academy Press, Washington DC, 331 pp.

Olvera, N., Martinez, P., Galvan, C. and Chavez, S. (1988) The use of the leguminous plant Sesbania grandiflora as a partial replacement for fish meal diets for tilapia (Oreochromis mossambicus). Aquaculture 71, 51-60.

Palmer, B. and Schlink, A.C. (1992) The effect of drying on the intake and rate of digestion of the shrub legume Calliandra calothyrsus. Tropical Grasslands 26, 89-93.

Rahman, N.N., Aktar, S., Hasan, C.M. and Jabbar, A. (1986) Anticancer agent from Albizia lebbeck. Acta Horticulturae 188, 69-81.

Raharjo, Y.C. and Cheeke, P.R. (1985) Palatability of tropical tree legume forage to rabbits. Nitrogen Tree Fixing Reports 3, 31-32.

Rawat, M.S.M., Negi, D.S., Pant, G. and Panwar, M.S. (1989) Spermicidal activity and chemical investigation of Albizia chinensis. Fitoterapia 60, 168-169.

Reed, J. and Soller, H. (1987) Phenolics and nitrogen utilisation in sheep fed browse. In: Herbivore Nutrition Research. Research papers presented at the Second International Symposium on the Nutrition of Herbivores. Australian Society of Animal Production occasional publication, p. 47.

Robertson, B.M. (1988) The nutritive value of five browse legumes fed as supplements to goats offered a basal rice straw diet. Master of Agricultural Studies thesis, The University of Queensland.

Romeo, J.T. (1984) Insecticidal amino acids in the leaves of Calliandra. Biochemical Systematics and Ecology 12, 293-297.

Rosenthal, G.A. and Janzen, D.H. (1979) Herbivores - their Interaction with Secondary Plant Metabolites. Academic Press, New York.

Seawright, A.A., Hegarty, M.P., James, L.F. and Keeler, R.F. (1985) (eds), Plant toxicology. Proceedings of the Australia-USA Poisonous Plants Symposium. Queensland Department of Primary Industry, Yeerongpilly, Brisbane.

Shqueir, A.A., Brown, D.L., Taylor, S.J., Rivkin, I. and Klasing, K.C. (1989) Effects of solvent extractions, heat treatments and added cholesterol on Sesbania sesban toxicity in growing chicks. Animal Feed Science and Technology 27, 127-135.

Shrivastava, K. and Saxena, V.K. (1988) A new saponin from the roots of Albizia lebbeck. Fitoterapia 59, 479-480.

Singh, C., Kumar, P. and Rekib, A. (1980) Note on some aspects of the feeding value of Sesbania aegyptica fodder in goats. Indian Journal of Annual Science 50, 1017-1020.

Sotelo, A., Lucas, B., Blanc, F. and Giral, F. (1986) Chemical composition of seeds of Gliricidia sepium. Nutrition Reports International 34, 315-322.

Strickland, R.W., Lambourne, L.J. and Ratcliff, D. (1987) A rat bioassay for screening tropical legume forages and seeds for palatability and toxicity. Australian Journal of Experimental Agriculture 27, 45-53.

Tendulkar, S.H., Toro, V.A. and Majgaonkar, S.V. (1984) Utilisation of hadga (Sesbania grandiflora) leaf meal in the diet of lactating cows. Livestock Adviser 9, 43-47.

Tripathi, A.K. and Rizvi, S.M.A. (1985) Antifeedant activity of indigenous plants against Diacrisia obliqua Walker. Current Science India 54, 630-631.

Twigg, L.E., Mead, R.J. and King, D.R. (1986) Metabolism of fluoroacetate in the skink (Tiliqua rugosa) and the rat (Rattus norvegicus). Australian Journal of Biological Sciences 39, 1-15.

van Eys, J.E., Mathius, I.W., Pongsapan, P. and Johnson, W.L. (1986) Foliage of the tree legumes gliricidia, leucaena, and Sesbania as a supplement to napier grass diets for growing goats. Journal of Agricultural Science (Cambridge) 107, 227-233.

Wheeler, J.W., Hedges, D.A. and Till, A.R. (1975) A possible effect of cyanogenic glucoside in sorghum on annual requirements for sulphur. Journal of Agricultural Science (Cambridge) 84, 377-379.


Previous Page Top of Page Next Page