Livestock Research for Rural Development

Volume 9 Number 1

Use of Trichantera gigantea leaf meal and fresh leaves as livestock feed

Nguyen Thi Hong Nhan, T R Preston* and Frands Dolberg**

Department of Animal Husbandry, Faculty of Agriculture, Cantho University, Vietnam
*University of Tropical Agriculture, Thu Duc, Ho Chi Minh City, Vietnam
**Department of Political Science, University of Arhus, Denmark

 

ABSTRACT

Studies were done to detemine the optimum inclusion rates in poultry diets of meals made from sun dried leaves of Trichantera gigantea meals, and of the fresh leaves in diets for ducks, as locally available sources of carotene and plant protein. Three trials were made in collaboration with smallholder farmers in Cantho City.

 In trial 1 a randomized block design was used with three levels (0, 2 and 6% air dry basis) of Trichantera leaf meal with 180 laying hens. The second trial lasted 10 weeks and evaluated 0 or 6% Trichantera leaf meal in the diet of 300 laying quails. The results for mean egg production and egg quality of laying hens and quails were similar for the control and experimental diets. The cost of production tended to be lower for diets with Trichantera leaf meal.

 In the third trial, 200 ducks were fed from 21 to 60 days of age to evaluate fresh leaves of Trichantera and water spinach in fattening diets. There were no significant differences between treatments for daily weight gain and feed conversion ratio. Carcass parameters were not affected by treatments, except that breast muscle percent increased with increasing intake of Trichantera.

 

Key words : Trichantera gigantea, water spinach, laying hen, laying quail, ducks.

 

Introduction

Village surveys in the Mekong delta (Nguyen Thi Kim Dong, personal communication) have shown that protein is likely to be the first limiting factor in poultry diets at the level of small scale farmers. Research is needed to explore the possibility of utilizing locally available protein resources, especially the leaves from multipurpose trees and water plants, to replace the conventional protein-rich concentrate meals. It is common practice by farmers in tropical countries to use small amounts of green feed to protect against possible vitamin deficiencies and to provide unidentified growth factors.

The multi-purpose tree Trichantera gigantea (Preston T R and Murgueitio E 1994), introduced into Vietnam from Colombia in 1991 has adapted readily to a wide range of ecosystems throughout Vietnam (Nguyen Ngoc Ha and Phan Thi Phan 1995; Nguyen Thi Hong Nhan et al 1996). The crude protein content of the foliage (leaves and the thin stems, which are also consumed by the animals) varies from 18 to 20 % in dry matter and apparently most of that is true protein and has a good amino acid balance (Rosales M, personal comunication). According to some early work there are few secondary plant compounds and the calcium content has been found to be particularly high compared to other fodder trees (Galindo et al 1989). Water spinach is another potential source of leaf protein and carotene (Naren Toung et al 1994) and is widely used by farmers in the Mekong Delta as a supplementary feed for their animals.

Three on-farm trials were conducted with the following objectives:


Materials and methods

Trial 1:

A total of 180 laying hens housed in cages made from bamboo were allocated to three diets; the control (C) containing 54% yellow maize and two test diets with broken rice instead of maize and either 2 or 6% of meal from sun dried leaves of Trichantera gigantea. The diet composition is in Table 1.

 

       
Table 1: Composition of diets for laying hens in Trial 1
Ingredients, %

Control

TG2

TG6

Maize meal

34

17

0

Broken rice

20

37

54

Rice bran

16

14

11

Soya bean meal

10

10

10

Coconut meal

4

4

4

Fish meal

10

10

10

Feather meal

3

3

3

Mineral mix

3

3

3

Lys+Met supp.

0.2

0.2

0.2

Trichantera leaf meal -

2

6

N*6.25, % in DM

18.5

18.5

18.8

Feed cost (VND/kg )

2400

2275

2150

 

Trial 2:

Three diets were fed to 300 laying quail during a period of ten weeks. The control diet contained yellow maize which in the experimental diets was replaced by Trichantera gigantea leaf meal (6% of diet) and cassava root meal as partial (TGP) or total (TGT) replacement of the maize meal. Details of the diets are in Table 2.


Trial 3:

In the third trial, 200 Snow White ducks were fattened from 21 to 60 days of age with diets based on broken rice and rice bran and with fresh leaves of Trichantera gigantea or water spinach (Ipomoea aquatic) offered on free choice basis. The basal diet was modified by reducing the levels of soya bean meal and fish meal by 10%. The treatments were: Control (basal diet), SBTG (Trichantera ad libitum and 10% reduction of soya bean meal in the basal diet); SBWS (same as SBTG but with water spinach instead of trichantera); FMTG (same as SBTG but with replacement of fish meal); and FMWS (same as FMTG but with water spinach). There were 4 replicates of the five dietary treatments (ten ducks per treatment/replicate). The composition of the control diet is in Table 5. The leaves were fed freshly harvested on ad libitum basis. At the beginning, and at the end of the experimental period and every 10 days in between, all ducks were individually weighed. Daily feed consumption was recorded on a pen basis.


Results and discussion

Trial 1: Laying hens

Substitution of maize by broken rice and trichantera leaf meal lowered the cost of the diet from 2,400 to 2150 VND/kg (1USD=VND11,000) with no change in the protein content.

The effects of the diets on production and on egg composition of egg are shown in Table 2.

Table 2: Effect of diets on production and composition of egg in laying hens .
 

Control

TG2

TG6

SE/Prob.

Egg production (%)

74.5

75.4

75.1

0.5/0.9

Feed consumption (g/egg)

138

138

121

3.2/0.6

Egg weight (g/egg)

56.9

56.5

56.2

0.9/0.8

Egg yolk (%)

26.9

26.8

26.4

0.3/0.57

Yolk color*

8.89

8.76

8.3

0.1/0.2

Feed cost (VND/egg )

329

313

260

0.6/0.3

*On scale of 1 to 10        

 

There were no differences in egg production between the three treatments; feed conversion was similar on the control and 2% Trichantera leaf meal diets (138g /egg) but a little lower with 6% Trichantera leaf meal (121g /egg). Feed cost (VND/egg) decreased gradually from 329 in the control to 313 and to 260 in the TG2 and TG6 treatments .


Trial 2: Laying quails

       
Table 3: Composition of diets for laying quails (Trial 2)
 Ingredient ( % )

Control

TGP

TGT

 Maize meal

 35

 20

 -

 Cassava root meal

 -

 15

 35

 Broken rice

18

 18

18

 Rice bran

 10

 4

 3

 Soybean meal

 18

 18

 18

 Fish meal

 16

 16

 16

 Feather meal

3

 3

 3

Lys + Met

 0.2

 0.2

 0.2

Trichantera leaf meal

 -

 6

 6

N*6.25 in DM

 24.8

 24.2

 24.1

 Mean values for egg production, feed conversion and egg quality are given in Table 4.

         
Table 4: Effect of diets on production and quality of eggs

  

Control

 TGP

TGT

 SE/Prob.

Egg production (%)

 84.8

 91.2

 89.7

 2.7 / 0.26

Feed consumption (g/egg)

 23.9

 23.4

 22.8

 1.3 / 0.8

Egg weight (g/egg)

 9.9

 10.4

 10.1

0.2 / 0.28

Egg yolk (%)

 28.9

 28.9

 28.4

 0.7 / 0.9

Yolk color*

 5.2

 6.3

5.8

 0.3 / 0.09

Feed cost (VND/egg)

 71

68

68

 2.2 / 0.5

 * On scale 1-10        

 

There was an indication (P=0.26) for egg production to be higher on the diets containing Trichantera leaf meal. Feed conversion was similar on all diets. Yolk color tended to be better (P=0.09) on the diets containing the Trichantera leaf meal. 

Trial 3: Fattening ducks

   
Table 5: Composition of the control diet for growing ducks
Ingredients ( % )

 Control

Broken rice

 40

Rice bran

 36

Soybean meal

 12

Fish meal

 12

Crude protein in DM

 18.8

It was not possible to collect precise data on the intake of the trichantera leaves and the water spinach but spot observations taken on weighing days indicated that the average intake (fresh basis) was in the range of 70-80 g/duck/day. This is equivalent on a dry matter basis to some 10% of the total daily intake. Sarria (1994) reported slightly higher levels of intake of Trichantera leaves, as a proportion of diet dry matter, in pigs. Growth performance data (Table 6) showed no differences between treatments.  

             
Table 6 : Effect of trial diets on growth performance of ducks
  Control SBTG SBWS FMTG FMWS SE/Prob.
Live weight, kg            
Initial

0.49

0.52

 0.51

 0.5

 0.51

 0.01/0.10

Final

 1.64

1.65

 1.64

 1.72

 1.6

 0.03/0.26

Gain (g/d)

 30.7

30.3

 30.7

 32.9

29.3

 0.03/0.13

Feed intake (g/d)            
Basal diet

 144

140

 139

 133

 140

 0.08/0.10

Trichantera leaves

0

70-80g/duck/day

 

 

At the end of the trial, four ducks per treatment (two females and two males) were slaughtered. Table 7 shows the results of the carcass analysis . The only significant effect of treatment was for breast muscle which increased from 8.05 % on the control to 10.5 for the FMTG treatment ( P=0.004). The skin color was observed to take on a bright yellow appearance in the ducks having access to the Trichantera.

 

             
Table 7: Effect of diets on carcass composition and intestine of ducks
 

Control

SBTG

SBWS

FMTG

FMWS

SE/Prob.

Carcass, % LW

73.84

 71.16

 76.36

 73.27

 75.87

 2.2/0.49

Breast muscle, %

 9.3ab

10.47a

 8.05b

10.51a

 9.09b

 0.4/0.004

 Leg muscle, %

6.75

6.73

 6.56

 6.85

 6.1

0.28/0.4

Length, cm            
 Small intestine

184

 185

 182

 185

189

2.7/0.6

 Large intestine

 136

 133

 141

 134

 141

6.2/0.8

 Caecum

 30.9

 31.1

 31.9

 32.2

 34.8

 1.04/0.12

 

A vitamin/mineral premix was not included in the diets and no deficiency symptoms were observed. This is an important advantage in rural areas where premixes may not be available or are expensive.

 
Conclusions and recommendations


Acknowledgments

 This research was supported financially by the International Foundation for Science through a grant (B /2231-1) to the senior author.

 
References

Galindo W, Rosales M, Murgueitio E and Larrahondo J 1989 Sustancias antinutricionales en las hojas de Guamo, Nacedero y Matarratón. Livestock Research for Rural Development. Volume 1, Number 1: 36-47

Naren Toung, Ogle B and Preston T R 1994 Optimum protein supply and level of inclusion of water spinach ( Ipomea aquatica ) in sugar cane juice based diets for growing ducks . MSc thesis in Sustainable Livestock Systems in the Tropics . Swedish University of Agricultural Sciences : Uppsala .

Nguyen Thi Hong Nhan, Nguyen van Hon, Vo Van Son, Preston T R and Dolberg F 1996 Effect of shade on biomass production and composition of the forage tree Trichanthera Gigantea. Livestock Research for Rural Development. Volume 8, Number 2: 93-98

Nguyen Ngoc Ha and Phan Thi Phan 1995 Vegetative propagation capacities and effect of fertilization on biomass production of Trichanthera gigantea. Livestock Research for Rural Development. Volume 7, Number 1 (10kb)

Preston T R and Murgueitio E 1994 Strategy for sustainable livestock production in the tropics . CONDRIT Ttda : Cali , Colombia .

Sarria Patricia 1994 Efecto del Nacedero ( Trichantera gigantea ) como reemplazo parcial de la soya en cerdas en gestacion y lactancia recibiendo una dieeta basica de jugo de cana . Livestock Research for Rural Development , Volume 6 , Number 1:62-73

Received 10 January 1997