Vigna unguiculata

Cowpea, black-eyed pea, cherry bean, southern pea, wonder pea

Trailing or bushy vigorous-growing annual with large seeds, blue- purple to white flowers, oval to heart-shaped leaves and flattened pods 10-20 cm long. Medium to late maturity (70-140 day).

An excellent crop to grow with maize for silage (one part cowpea vines and two parts maize). Also cultivated as a pasture, hay or silage crop. The straw and seed-harvested vines used for all kinds of livestock. The vines should be cut for hay when most of the pods are all grown and a considerable number of them are mature. If cured by much exposure to the sun, the leaves fall off. Cowpea hay is an excellent roughage for all kinds of livestock; if chopped and moistened, it is suitable for poultry as well. Mixed with ground maize it has proved quite satisfactory for brood sows. There is much waste from trampling if stock is allowed into cowpea fields before the plants are full-grown. To avoid this, cowpeas can be used for zero grazing or can be grazed by pigs before cattle or sheep.

Yields of fresh fodder can be increased by cutting the plants twice in a season. Cowpea can be grown with Sudan grass for hay and with maize for silage. The seeds are initially too expensive for animal feed, but are used to some extent for poultry. The harvesting of seed is costly because of the uneven ripening of the pods. Culled peas are sometimes used for pigs. Although there is no evidence of toxicity, the gain in weight usually decreases as the percentage of raw beans increases in the ration. This effect can largely be eliminated by autoclaving the beans (at 121 C for 15 minutes) before feeding.

As % of dry matter

DM

CP

CF

Ash

EE

NFE

Ca

P

Ref

Fresh aerial part,

Malaysia

11.1

30.6

24.3

14.4

1.8

28.9

2.06

0.31

292

Fresh, mid-bloom,

Tanzania

27.5

17.7

12.7

3.9

38.2

487

Haulm, Nigeria

17.5

24.9

7.8

1.6

48.2

58

Hay, South Africa

14.4

22.3

9.9

2.3

51.1

1.33

0.18

489

Seed, Malaysia

92.6

24.9

5.2

4.0

1.5

64.4

0.27

0.42

292

Seed, Trinidad

88.0

22.5

3.5

3.3

1.4

69.3

117

Pod husks, Nigeria

92.6

13.0

33.4

7.2

0.7

45.7

374

Digestibility (%)

Animal

CP

CF

EE

NFE

ME

Ref

Haulm

Cattle

73.1

48.2

31.3

69.7

2.24

58

Hay

Sheep

64.1

52.7

34.5

80.5

2.38

489

Nylon bag degradability

a

b

c

12hr

48hr

Ref

(%)

(%)

(/hour)

(%)

(%)

Cowpea 3-4 weeks (early)

DM

3.9

71.1

0.0911

51.2

74.1

631

N

37

67.6

0.0535

69

99.4

"

Cowpea 2nd growth,

1 month (late)

DM

10

61.9

0.0647

43.4

69.1

"

N

37.7

53.2

0.0389

57.5

82.7

"

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

Amino acid composition as % of crude protein

Aerial part

Ref

188

Arg

Cys

Gly

His

Ils

Leu

Lys

Met

Phe

Thr

Try

Tyr

Val

4.6

0.9

4.8

1.8

4.3

7.4

3.0

1.8

4.6

4.6

1.4

3.2

5.3

Seed

Ref

259

Arg

Cys

Gly

His

Ils

Leu

Lys

Met

Phe

Thr

Try

Tyr

Val

7.0

-

3.9

3.3

6.2

11.3

6.5

0.9

6.0

5.3

1.3

2.8

4.9