Leucaena leucocephala

Koa haole, ipil-ipil, white popinac, lead tree, wild tamarind, cow tamarind, shack shack

Deep-rooted tree or arborescent shrub up to 10 m high with bipinnate leaves, lanceolate leaflets and yellow-white flowers in long-stalked heads. (The flat pods contain small seeds that are popular in jewellery and novelties.) Native to Mexico, but cultivated widely in the tropics as a fodder plant, especially on dry wastelands where little else will grow. For prepared fields and planted pastures it is desirable to interplant koa haole with a grass cover, most commonly Guinea grass - a mixture that has proved excellent for fattening. Koa haole cannot be grazed heavily and continuously without being exterminated; it should not be used for grazing more than five months a year. Topping the plants about 1 m above the ground keeps the young shoots within reach of browsing cattle and prevents cows from snagging their udders on the stumps. On acid soils, liming is essential.

Toxicity. The leaves and seeds contain the glucoside mimosine, which may cause loss of hair in horses and young cattle. The addition of iron salts decreases toxicity, and if the treated material is allowed to stand for a week before being mixed with feeds, little toxicity remains. The mimosine content can also be reduced by soaking in water and drying. Sheep should be introduced to koa haole gradually to increase their ability to detoxify the feed. The ill effects of mimosine are erratic, and sometimes no effects are observed even when koa haole is the sole feed.

The young foliage is very palatable to cattle, rich in protein and nutritious. Pods and seeds are used in some countries as a concentrate for cattle. Feeding trials with swine have shown no ill effects from rations consisting of up to 15% koa haole leaves. The leaves should not be fed to breeding animals, however, as they may affect reproduction. When included in poultry rations, production usually decreases and the birds take longer to reach sexual maturity. A small (5%) inclusion of dried koa haole seems to increase the hatchability of eggs in some cases.

As % of dry matter

DM

CP

CF

Ash

EE

NFE

Ca

P

Ref

Fresh leaves,

Thailand

21.0

18.1

8.4

6.5

46.0

56

Fresh twigs,

young, Malaysia

31.6

27.8

10.4

3.5

3.2

55.1

0.54

0.29

292

Fresh browse,

dough stage, Hawaii

30.7

24.2

24.2

8.9

2.7

40.0

515

Pods, Zimbabwe

21.7

25.6

5.8

1.4

45.5

19

Seeds, Zimbabwe

91.0

35.8

11.4

4.4

7.5

40.9

499

Digestibility (%)

Animal

CP

CF

EE

NFE

ME

Ref

Browse

Cattle

65.0

35.0

36.0

74.0

2.13

515

Nylon bag degradability

a

b

c

12hr

48hr

Ref

(%)

(%)

(/hour)

(%)

(%)

Leucaena, crushed, Ghana

DM

28.7

55.7

0.0209

65.8

627

Leaves, freeze dried

DM

74.7

82.1

630

N

83.3

"

Leucaena, 6 weeks

DM

70.1

632

Leucaena, 12 weeks

DM

64.3

"

[P (rumen degradability at time t) = a+b*(1-exp(-c*t))]

Amino acid composition as % of crude protein

Leaf

Ref

433

Arg

Cys

Gly

Hys

Ils

Leu

Lys

Met

Phe

Thr

Try

Tyr

Val

6.4

3.3

5.1

2.7

5.0

9.0

6.7

1.4

5.4

4.6

-

4.3

5.8

Seed

Ref

376

Arg

Cys

Gly

Hys

Ils

Leu

Lys

Met

Phe

Thr

Try

Tyr

Val

4.3

0.6

-

3.5

1.9

2.4

2.9

0.3

1.9

1.9

0.5

1.4

3.2