F. Uribe Trujillo
Médico Veterinario Zootecnista
Hacienda Lucerna Ltda.
Bugalagrande, Valle, Colombia
INTRODUCTION
Mulberry (Morus sp.) foliage, characterized by its high digestibility and good protein content, has great possibilities for use in animal feeding, both for ruminants and for monogastrics.
Manuel Vicente de la Roche introduced mulberry to Colombia in 1868, but its propagation only started in 1970 when the Colombian Coffee Growers Federation decided, as part of its diversification programmes, to destine resources for the study and adaptation of mulberry in the coffee regions of Caldas, Risaralda and Cauca. Kanva 2 (M. indica) is the most widespread variety in the country (Federación Nacional de Cafeteros de Colombia, 1984).
CULTIVATION
The ideal soil for mulberry should have medium texture, with 60 cm in depth, phreatic level of at least 1 m, good drainage, pH 6-7 and good organic matter. Mulberry does not tolerate flooding.
Mulberry is reproduced asexually. Stakes should be 15-20 cm in length and 18-20mm in diameter. It is important to use matured stems (more than three months of age), with stakes chosen from the middle part.
Direct planting is not recommended because of high failure, high weeding cost and low resistance to the dry period. Rooting is done on 1.20 m x 0.10 m beds, where stakes are planted with a spacing of 10 x 20 cm, burying two-thirds of the stake. Beds are covered with a plastic sheet to control humidity and weeds. After 45 days, the plastic is cut to allow aeration. The operation should last two to three months. Transplanting is carried out by pulling the plants from the bed, removing the leaves and once planted, by pruning to 10-15 cm.
Recommended density lies between 25 and 32 000/ha (e.g. 80 x 40 cm; 80 x 50 cm; 90 x 40 cm). It is advisable to apply 50 kg of calcium phosphate and 400 g of organic matter per plant at transplanting.
Strict weed control is required during establishment since weeds are one of the mayor problems of the forage crop.
Three prunings are recommended: formation pruning (to 20 cm) after two or three months of transplanting, to shape the plant (productive crown) and to encourage shooting; regular harvests at 20-40 cm, 1 cm higher than the previous cut, every 75-90 days; and rejuvenating pruning (to 10-20 cm) after the plant has formed a multiple-shoot high crown called "deer's antlers" which has low productivity.
Forage production increases up to the third year (Cifuentes and Han, 1992), when yield reaches 30-50 tonnes of fresh leaves per year. At Hacienda Lucerna, the average production is 50t/ha/year of fresh leaves with 90 days cuts. In 1993, an evaluation was initiated with the combination of mulberry with Gliricidia sepium, mixed planted at a spacing of 40-60 cm between plants in double lines 1 m apart. The objective was to profit from the N fixation by Gliricidia. With this system annual yields of fresh foliage of 60t/ha of mulberry and 30t/ha of Gliricidia, have been obtained.
NUTRITIVE VALUE
Digestibilities between 80 and 93 percent have been reported for mulberry leaves and 50 percent for stems (Benavides, 1995). Velázquez (1992) found 205 ppm of Ca, 55 ppm of P, 6.0 ppm of Fe and 0.4 ppm of Zn.
Mulberry leaves (Kanva 2) from Hacienda Lucerna had 20.0 percent DM, 15.8 percent CP, 11.5 percent CF, 4.6 percent EE, 50.9 percent N-free extract and 17.3 percent ash, with a calculated net energy value of 2.4 Mcal/kg (González and Mejía, 1994).
ANIMAL RESPONSE
The work by Benavides (1995) with goats is a good example of the positive impacts achieved with woody plants, such as mulberry, during the last decade in Costa Rica. The use of larger quantities of mulberry is reflected in bigger flocks and better production.
In Guatemala, when feeding increasing levels of mulberry to young bulls on a base diet of sorghum silage, total intake and weight gains improved while consumption of salt and mineral decreased (Velázquez, 1992).
At Hacienda Lucerna a study was conducted in order to evaluate mulberry as partial replacement of concentrate in the rearing of diary heifers (Gonzalez and Mejía, 1994). The work consisted in the technical and economic evaluation with replacement heifers of tree levels (100, 75 and 50 percent) of commercial concentrate (with 16 percent protein), substituting 25 and 50 percent with fresh mulberry leaves. Thirty Lucerna (a criollo breed) heifers from five days old and 30 kg of weight were reared with the restricted suckling method for 112 days. Average weight gains were 0.406, 0.437 and 0.406 kg/day for the 0, 25 and 50 percent replacement, respectively.
From this experiment, the following conclusions were drawn:
TABLE 1
Daily intake (kg) of heifers supplemented with fresh mulberry leaves
|
|
Treatments (concentrate: mulberry) |
||
|
|
100: 0 |
75: 25 |
50: 50 |
|
Total DM intake |
0.372 |
0.514 |
0.415 |
|
Mulberry intake |
0 |
0.307 |
0.299 |
Source: Gonzales and Mejía, 1994.BIBLIOGRAPHY
Benavides. J.E. 1995. Arboles y arbustos forrajeros para las montañas americanas. In: Sistemas pecuarios sostenibles para las montañas tropicales,. p.103-123., Cali, Colombia, CIPAV.
Cifuentes, C.A. & Han, K.M. 1992. Manual de sericultura. Plan Nacional de Rehabilitación. Ed. Imprimiendo Ltda., Pereira, Colombia.
Federación Nacional de Cafeteros de Colombia. 1986. Programa de desarrollo y diversificación de zonas cafeteras. Proyecto sericultura. Santafé de Bogotá, Colombia.
Gómez, M.E., Rodríguez, L., Murgueitio, E., Ríos, C.I., Molina, C.H., Molina, E. & Molina, J.P. 1995. Arboles y arbustos forrajeros utilizados en alimentación animal como fuente de proteína. p.1-11. CIPAV, Cali, Colombia.
González, S.E. & Mejía, I. 1994. Utilización de la morera (Morus indica) como reemplazo parcial del concentrado en la crianza de terneras. Facultad de Zootecnia, Universidad Nacional de Colombia, Palmira, Colombia. (thesis).
Velázquez, C.M. 1992. La morera como fuente de proteína en dietas a base de ensilado de sorgo para novillos en Cuyuta. Facultad de Zootecnia, Instituto de Ciencia y Tecnología Agrícola, Guatemala. (thesis).
