Performance of growing goats fed Gliricidia maculata
Introduction
In the tropical wet zone of south east Asia, most of the arable land has been utilised for high value food crops and industrial crop production (Chen et al., 1991). The ruminant livestock production in these areas plays a complementary role in utilising the by-products of crops and getting some income from land unsuited to crop production. The fibrous crop by-products are the major potential feed resources, and the by-products from rice are most abundant, followed by those from cassava, maize, cotton seed and banana. However, the fibrous crop by-products are characterised by extensive lignification of the cellulose and the hemicellulose, and by low levels of protein, soluble carbohydrates and minerals. As a consequence, the intake and digestibility of these feeds are not sufficient to sustain satisfactory levels of production. Supplementation with protein, but also with soluble carbohydrates, is very important for obtaining a good production (Chen et al., 1991). The leaves from leguminous trees and shrubs are cheap and readily available sources of protein. One of the possible species that can be used is Gliricidia maculata. Ella (1988) reported that the annual dry matter (DM) leaf yield of Gliricidia was around 23 t/ha.
The chemical composition and nutritive value of Gliricidia place it among the high quality forages from tropical areas. NFTA (1987) reported that the evaluations of Gliricidia as an animal feed for beef and dairy cattle, sheep and goats have shown promising results. The range of nutritive values found, as percent of DM were according to NFTA (1987) dry matter digestibility (DMD) 48–77%, crude protein (CP) 18–30%, acid detergent fibre (ADF) 18–34%, neutral detergent fibre (NDF) 27–50%, crude fibre (CF) 13–30%, ether extract 4–8%, ash 6–10% and calcium 1–2%.
The utilisation of Gliricidia as a fodder for farm animals has been tested in Central America, Africa and Asia (Devendra, 1990) and according to Wiersum and Nitis (1992) and Stewart and Simons (1994) Gliricidia has the potential to become a major source of feed for goats and cattle in dry land farming areas. The objectives of the present experiment were to evaluate the effect of feeding different levels of Gliricidia leaves as a protein source in diets based on locally available crop by-products on the growth of goats and to see if the digestibility of rice straw could be improved by supplementation with Gliricidia.
Section snippets
Location and climate of the study area
The experiment was conducted at the experimental farm of the National University in Ho Chi Minh City. The climate in the area is tropical monsoon, with a dry season between November and April and a wet season from May to October with an average of 1600 mm rainfall. The mean annual temperature is 28°C. The experiment was conducted between April and June 1998, a year when the wet season started very late (June).
Experimental animals and feeds
The animals were selected from a flock of goats raised in a confinement system. For the
Results
The chemical composition of the feeds used in the experiments is shown in Table 1. Cassava chips and rice straw had low contents of CP while Gliricidia leaves, cotton seed cake and rice bran contained high amounts of CP. Gliricidia, cotton seed cake and rice straw had a high content of NDF and ADF.
In the growth experiment there were significant differences among the treatments in the total intake of DM, OM, CP, ADF and NDF (Table 2). Total DM intakes were higher for the diets containing
Discussion
Gliricidia has a strong, unpleasant odour and it is reported (Nitis et al., 1991) that cattle may go off feed when firstly introduced to a Gliricidia sepium diet, while goats did not seem to be affected. The odour can be minimised by wilting, by harvesting the leaves in the evening and feeding to livestock the next day (Nitis et al., 1991). The goats in this experiment had been fed Gliricidia maculata earlier. The animals were adapted to eating the Gliricidia within the first few days of the
Conclusions
Replacing 30% of the DM in the diet with Gliricidia resulted in increased total intake of DM, OM and CP. There were no significant differences in growth rate due to level of Gliricidia in the diet. DM digestibility for straw was 55.5%, and for pure Gliricidia, 64.1%. Combinations of straw and Gliricidia had intermediate digestibilities, somewhat lower than calculated values suggesting that there was no positive interaction between the straw and the Gliricidia. The results indicated that
Acknowledgements
The authors would like to acknowledge the Swedish International Development Authority (SIDA) which sponsored this study. We also thank the Swedish University of Agricultural Sciences, Department of Animal Nutrition and Management, Uppsala and members of the staff of the Animal Nutrition Department of the University of Agriculture and Forestry, Ho Chi Minh City.
References (31)
The effect of supplementation with leaves from the leguminous trees Sesbanina grandiflora, Albizia chinensis and Gliricidia sepium on the intake and digestibility of Guinea grass hay by goats
Anim. Feed Sci. Technol.
(1990)- et al.
Supplementation of rice straw with crop by-products. In Legume straw supplementation
Anim. Feed Sci. Technol.
(1988) - et al.
The voluntary intake and digestibility of combination of cereal crop residue and legume hay for sheep
Anim. Feed Sci. Technol.
(1985) - et al.
Fodder tree and straw diets for sheep: intake, growth, digestibility and the effects of phenolics on nitrogen utilization
Anim. Feed Sci. Technol.
(1990) - et al.
Replacement value of Gliricidia sepium for growing goats
Anim. Feed Sci. Technol.
(1994) - AOAC, 1985. Association of Analytical Chemists. Official Methods of Analysis, 12th Edition. Arlington, VA, USA, 975...
- et al.
Effect of Gliricidia maculata on growth of Bannur ewes
Trop. Grassl.
(1980) - Chen, C.P., Halim, R.A., Chin, F.Y., 1991. Fodder trees and fodder shrubs in range and farming systems of the Asian and...
- Crowder, L.V., Chheda, H.L., 1982. Tropical Grassland Husbandry. Longman, London, 562...
- Devendra, C., 1990. Shrubs and tree fodders for farm animals. Country case study. In: Proceedings of a Workshop,...