Mulberry for Rearing Dairy Heifers
Fernando Uribe Trujillo
Hacienda Lucerna Ltda. Bugalagrande, Valle, Colombia
Mulberry (Morus spp) foliage, characterised by its high digestibility and good protein content, has great possibilities to be used in animal feeding, both for ruminants and for monogastrics.
Mr. 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 most spread variety in the country. (Federación Nacional de Cafeteros de Colombia 1984)
Ideal soil for mulberry should have medium texture, with 60cm in depth, phreatic level of at least 1m, good drainage, pH 6-7 and good organic matter. It does not support flooding.
It is reproduced asexually. Stakes should be 15-20cm in length and 18-20mm in diameter. It is important to use matured stems (more than three months of age), and stakes are chosen from the middle part.
Direct planting is not recommended due to high failure, high weeding cost and low resistance to the dry period. Rooting is done on 1.20m x 0.10m beds, where stakes are planted with a spacing of 10 x 20cm, burying 2/3 of the stake. Beds are covered with a plastic sheet to control humidity and weeds. After 45d, the plastic is cut to allow aeration. The operation should last 2-3 months.
Transplanting is done by pulling on the plants from the bed, removing leaves and once planted, by pruning to 10-15cm.
Recommended density lies between 25 to 32,000/ha (e.g. 80 x 40cm; 80 x 50cm; 90 x 40cm). It is advisable to apply 50 kg of calcium phosphate and 400g of organic matter by plant at transplanting.
Strict weed control is required during establishment, since weeds are one of the most important problems of the forage crop.
Three prunings are recommended: 1) Formation pruning (to 20cm) after two or three months of transplanting, to shape the plant (productive crown) and to encourage shooting; 2) Regular harvests at 20-40cm, 1cm higher than the previous cut, every 75-90 days; and 3) Rejuvenating pruning (to 10-20cm) after the plant has formed a multiple-shoot high crown called "deer's antlers" with has low productivity.
Forage production increases up to the third year (Cifuentes, 1992), when yield reaches 30-50t of fresh leaves per year. At Hacienda Lucerna, average production is 50t/ha/year of fresh leaves with 90d cuts. In 1993, an evaluation was initiated with the combination of mulberry with Gliricidia sepium, mixed planted at a spacing of 40-60cm between plants in double lines 1m 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.
Digestibilities between 80-93% have been reported for mulberry leaves and 50% for stems (Benavides, 1995). Velázquez (1992) found mineral contents of 205ppm for calcium, 55ppm for Phosphorus, 6.0ppm for iron and 0.4ppm for zinc.
Mulberry leaves (Kanva 2) from Hacienda Lucerna had 20.0% dry matter, 15.8% crude protein, 11.5% crude fibre, 4.6% ether extract, 50.9% N-free extract and 17.3% ash, with a calculated Net Energy value of 2.4Mcal/kg (González and Mejía, 1994).
The work by Benavides (1995) with goats is a good example of the positive impacts achieved with woody plants, such a mulberry, during the last decade in Costa Rica. The use of larger quantities of mulberry use are reflected in larger 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%) of commercial concentrate (with 16% protein), substituting 25 and 50% with fresh mulberry leaves. Thirty Lucerna (a criollo breed) heifers from 5 days old and 30kg of weight were reared with the restrict suckling method for 112d. Average weight gains were 0.406, 0.437 and 0.406 kg/d for the 0, 25 and 50% 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 dry matter intake||
Gonzales and Mejía, 1994
Benavides. J.E. 1995. Arboles y arbustos forrajeros para las montañas americanas. En: Sistemas Pecuarios Sostenibles para las Montañas Tropicales. pp103-123 CIPAV, Cali, Colombia.
Cifuentes, C.A. y Han, K.M. 1992. Manual de sericultura. Plan Nacional de Rehabilitación Ed. Imprimiendo Ltda., Pereira, Colombia.
Gómez, M.E.; Rodríguez, L.; Murgueitio, E.; Ríos, C.I.; Molina, C.H.; Molina, E. y Molina, J.P. 1995. Arboles y arbustos forrajeros utilizados en alimentación animal como fuente de proteína. pp1-11 CIPAV, Cali, Colombia
González, S.E. y Mejía, I. 1994 Utilización de la Morera (Morus indica) como reemplazo parcial del concentrado en la crianza de terneras. Tesis de grado, Facultad de Zootecnia, Universidad Nacional de Colombia, Palmira, Colombia.
Federación Nacional de Cafeteros de Colombia. 1986. Programa de desarrollo y diversificación de zonas cafeteras. Proyecto sericultura. Bogotá, Colombia.
Velázquez, C.M. 1992. La Morera como fuente de proteína en dietas a base de ensilado de sorgo para novilllos en Cuyuta. Tesis de grado, Facultad de Zootecnia, Instituto de Ciencia y Tecnología Agrícola, Guatemala.