World distribution and utilization of mulberry and its potential for animal feeding

Manuel D. Sánchez
Animal Production Officer
Animal Production and Health Division
FAO, Rome

INTRODUCTION

The scientific name of mulberry is Morus spp., a genus belonging to the Moraceae family of the Urticales subclass. Mulberry is usually associated with sericulture, the production of silk through the silkworm (Bombyx mori). The domestication of mulberry started several thousands of years ago as a requirement for silkworm rearing (FAO, 1990).

Considering that the silk trade has existed for a long time throughout the Old World and that mulberry is also cultivated for its fruit and for landscaping, its germplasm has been taken to many countries, and it now has a very wide distribution range in Asia and Europe (from Korea to Spain, including China, India, Central Asia and the Near East); in Africa (North and East Africa) and in the Americas (from the United States to Argentina, including Mexico, Central America, Colombia and Brazil). The origins of most cultivated mulberry varieties are believed to be in the China/Japan area and in the Himalayan foothills.

Silk production was important in Europe during the nineteenth and early twentieth centuries, as it was in Japan and Korea up to the middle of the twentieth century. Silk production nowadays is dominated by China and India.

Although in some countries of Asia mulberry leaves have been traditionally fed to farm animals, interest in the intensive production of mulberry and its utilization for animal production started in several countries in the late 1980s and early 1990s. The attractive biomass yields, palatability and exceptionally high nutritive value for ruminant and monogastric animals have been the reasons behind the great interest in mulberry for animal feeding in recent years.

This introductory paper gives a general framework of mulberry in the world without going into specific details, which will be covered and discussed in other conference papers.

SPECIES AND VARIETIES OF MULBERRY

There are about 68 species of the genus Morus, and the majority of them occur in Asia (Datta, 2000). In China, there are over a thousand varieties under cultivation. They originated from four main species, the White mulberry (Morus alba), the Lu mulberry (M. multicaulis), the Mountain mulberry (M. bombycis) and the Guangdong mulberry (M. atropurpurea) (Yongkang, 2000).

In India the main species are M. indica, M. alba, M. serrata and M. laevigata, which grow naturally in the north of the country (Ravindran et al., 1997). Most of the cultivated varieties belong to either M. indica or M. alba. In Mysore, India, the Central Sericulture Research and Training Institute keeps 244 mulberry cultivars: 78 indigenous, 44 exotic, 21 unknown and 101 elite hybrids (Sastry, 1984).

In the republics of the former Soviet Union, the most common species are M. multicaulis, M. tartarica and M. nigra (Datta, 2000). In Indonesia (West Java) there are seven species: M. alba (varieties tartanica and macrophyla), M. nigra, M. multicaulis, M. australis, M. cathyana and M. mierovra (Katsumata, 1972). In Viet Nam there are over 100 varieties, mainly M. alba, M. nigra and M. laevigata (Katsumata, 1973). According to Janaki Ammal (1960) only M. rubra is native to the Americas.

The most popular species in the world are believed to be M. alba and M. indica. These have been the subject of intensive selection from open pollination, controlled hybridization and selection and mutation breeding in several countries, resulting in over a thousand varieties, including many polyploids. In Brazil there are about 90 varieties, all M. alba (de Almeida and Fonseca, 2000).

A key to the taxonomy of mulberry, as proposed by Chinese scientists, is included in the paper on mulberry in China on p.11 (Huo, 2000).

CURRENT USES OF MULBERRY

Sericulture

The most important use of mulberry globally is in the production of silkworm, which feeds exclusively on its leaves. The country with the largest area of mulberry is China with approximately 626 000 ha, then India with nearly 280000 ha. Several other countries, such as Thailand and Brazil (35 000 ha), still have some mulberry production but on a much smaller scale.

Silk projects have been and are being started in various developing countries, particularly in Africa and Latin America. Regardless of how successful or sustainable they have been, these projects have been responsible for the introduction and dissemination of mulberry varieties under different soil and climatic conditions.

Fruit

All throughout Asia, but particularly in Central Asia and in the Near East, mulberry is highly appreciated for its delicious fruit, which is consumed fresh, or in the form of juice or conserves. A few mulberry orchards also exist in Latin America.

Wood

Especially in the Indian subcontinent, mulberry wood is used for handicrafts, cabinet work and for sporting woods (e.g. grass-hockey sticks and tennis rackets). Its thin branches are woven into baskets.

Landscaping

In Asia, southern Europe and in the southern United States, mulberry trees are utilized for landscaping (Tipton, 1994). Their resistance to pruning and their low water requirements make them very suitable plants for urban conditions, house gardens, street shade and city embellishment.

Medicine

A variety of medicinal properties has been attributed to the different parts of the mulberry plant (Datta, 2000). Leaves are also dried and used in infusions in Asia (e.g. China and Thailand).

Forage

Silk producers have traditionally fed mulberry surpluses from silkworm feeding to farm animals and to herbivorous carp in polyculture fish ponds (Gongfu, Zengqi and Houshu, 1997). In this sense, farm animals are well integrated into silk production. There have even been economic studies of the combined benefits from silk and dairy production in India (Mehla, Patel and Tripathi, 1987). A review of mulberry for animal feeding has been published by FAO (FAO, 1999).

In countries south of the Himalayas, where mulberry trees occur in nature, their foliage has been part of the traditional mixed diet of domestic ruminants. In India there have been numerous research reports on the use of mulberry residues and leaves for various domestic animals, from cows to poultry. In general terms, Indian scientists have considered mulberry foliage as medium-quality forage.

Some small farmers in East Africa, mainly in the United Republic of Tanzania and in Kenya, harvest foliage from mulberry trees and include it as part of the diet offered to ruminants in confinement. Although its nutritive value is recognized in these countries, there has been little planting of mulberry for this purpose.

Since the late 1980s and mainly in the late 1990s, the cultivation of mulberry as forage has expanded considerably in Latin America, in Central America and in the Caribbean in particular, but it is still mainly associated with research institutions. This has been mainly the result of the initial studies carried out by the Tropical Agriculture Research and Higher Education Center (CATIE) in Costa Rica and in other Central American countries (Benavides, 1994) and the expansion by a number of research and development projects. There have been, however, in other countries in Latin America (e.g. Brazil and Colombia), independent initiatives to feed mulberry leaves to various species of farm animals.

MULBERRY RESEARCH

Beginning in the nineteenth century extensive research on the various components of the cultivation of mulberry has been carried out in several countries, depending on the viability of the local silk industry. A great deal of work took place in several European countries, for example, France, Italy, Bulgaria and Poland. By the middle of the twentieth century, silk production in Europe had practically disappeared. Significant production and research also took place in Japan and Korea in the middle of the twentieth century.

Currently, most of the mulberry research for sericulture takes place in China and India, with several institutions actively involved in both countries. For fruit and for silk production, studies are being carried out in the Central Asian republics of the former Soviet Union, for example, in Uzbekistan, Turkmenistan, Tajikistan and Kyrgyzstan.

Studies on mulberry as animal feed are being or have been conducted in Japan, India, the United Republic of Tanzania, Kenya, Costa Rica, Colombia, Mexico, El Salvador, Guatemala, Brazil and Cuba. The most active research on mulberry for animal feeding is currently taking place in Cuba. Research includes agronomic aspects, harvesting modalities, forage preservation and animal trials.

POTENTIAL OF MULBERRY FOR ANIMAL PRODUCTION

It is not by chance that mulberry germplasm is causing so much interest as an alternative high-quality feed for farm animals. Over several hundreds, and perhaps thousands, of years, mulberry species and varieties have been selected and improved to feed the silkworm, which is nutritionally very demanding. The aim has been to produce greater quantities of leaves of higher quality under a wide range of conditions (in the tropical, subtropical and temperate regions).

Although, in general terms, the principles of mulberry cultivation for sericulture purposes should apply to its cultivation as forage for feeding farm animals, there are certain important differences. Frequency of harvesting and, in particular, planting density, can be intensified if the goal is to feed ruminants, since the quality is already high enough and the main purpose is to increase overall biomass yields. The issues of maintenance of soil fertility and plant persistence become important if huge quantities of nutrients are extracted from the soil in the biomass under cut-and-carry systems.

Individual leaf picking, as is commonly practised for silkworm feeding, can only be justified for small-scale or family units of mini-livestock, such as snails, guinea pigs or rabbits. Mechanical harvesting might be more appropriate for ruminant feeding in larger operations.

Feeding ruminants

The urgent need for a high-quality feed for ruminants in the tropics, in particular for small ruminants, and the excellent characteristics of mulberry, are the justifications for the great enthusiasm over its intensive cultivation and use as a feed supplement for cattle, and as the main feed for goats.

The nutritional quality of locally produced mulberry leaves is equivalent to that of grain-based concentrates. Thus, they are an ideal supplement in most forage diets.

The greatest impact of mulberry on livestock productivity is to be expected in the dairy cattle sector in the tropical regions.

Feeding mini-livestock

The nutritive value of mulberry leaves becomes greater in inverse proportion to animal size, since metabolic rate and hence nutrient requirements decrease with size (to the power of 0.75). Mulberry leaves should be the preferred feed for guinea pigs, rabbits and perhaps snails. The performance of dairy goats fed mulberry-based diets in Costa Rica has been impressive (Oviedo et al., 1994). Many more excellent results are to be expected when mulberry is offered to other herbivores, particularly small species.

Mulberry for browsing

Several studies have examined the possibility of mulberry for direct browsing by cattle in Italy (FAO, 1993), in France (Armand and Meuret, 1995) and in Japan (Kitahara, 1999). Although the results have been promising, a great deal of work will need to be done before mulberry is incorporated into grazing systems on a large scale.

The Table summarizes the utilization of and research on mulberry in different parts of the world.

Country summary of mulberry area (1 000ha), use and research

	Country	Area	Utilization				Research
			Silk	Fruit	Forage	Other*	Agr.	Breed.	Feed
AFRICA	Egypt and Tunisia	n.a.**	Ö	Ö			Ö
	Ethiopia	n.a.	Ö				Ö
	Kenya	n.a.	Ö		Ö		Ö		Ö
	Madagascar	n.a.	Ö				Ö
	Tanzania	n.a.			Ö				Ö
AMERICAS	Argentina and Bolivia	n.a.				Ö1
	Brazil	38	Ö		Ö		Ö	Ö	Ö
	Colombia	n.a.	Ö		Ö		Ö
	Costa Rica	n.a.			Ö		Ö		Ö
	Cuba	<1			Ö		Ö		Ö
	Dominican Rep.	<1			Ö
	El Salvador	<1			Ö				Ö
	Guatemala	n.a.			Ö				Ö
	Honduras and Panama	<1			Ö
	Mexico	<1	Ö	Ö	Ö	Ö1	Ö		Ö
	Panama	<1			Ö
	Peru	n.a.				Ö1
	Saint Vincent	<1			Ö
	United States	n.a.				Ö1			Ö
ASIA	Afghanistan	n.a.			Ö
	China	626	Ö			Ö2	Ö	Ö
	India	280	Ö		Ö	Ö3	Ö	Ö	Ö
	Indonesia	n.a.	Ö
	Japan	n.a.	Ö	Ö	Ö	Ö2	Ö	Ö	Ö
	Korea	n.a.	Ö		Ö		Ö	Ö
	Kyrgyzstan	n.a.	Ö	Ö			Ö
	Malaysia	n.a.	Ö				Ö
	Pakistan	n.a.	Ö		Ö		Ö
	Philippines	n.a.	Ö				Ö
	Syrian Arab Republic and Turkey	n.a.		Ö
	Tajikistan	n.a.	Ö				Ö
	Turkmenistan	n.a.	Ö	Ö			Ö
	Viet Nam	n.a.	Ö		Ö		Ö	Ö
	Uzbekistan	n.a.	Ö				Ö
EUROPE	Bulgaria	n.a.					Ö
	France	n.a.			Ö	Ö1	Ö		Ö
	Greece	n.a.				Ö1
	Italy	n.a.				Ö1	Ö		Ö
	Poland	n.a.					Ö
	Spain	n.a.				Ö2

* Other uses: ¹Landscaping and gardening; ²Medicinal and infusion;
³ Handicrafts and cabinet work ** n.a. data not available

Armand, D. & Meuret, M. 1995. Culture en sec et utilisation en élevage de Morus alba "Kokuso 21" en Provence. Rapport final (1991-94). Avignon, France, INRA.

Benavides, J.E. 1994. Arboles y arbustos forrajeros en América Central. Costa Rica, CATIE.

Datta, R.K. 2000. Mulberry cultivation and utilisation in India. Proceedings of the electronic conference. de Almeida, J.E. & Fonseca, T.C. 2000. Mulberry germplasm and cultivation in Brazil. Proceedings of the electronic conference.

FAO. 1988. Mulberry cultivation. FAO Agricultural Services Bulletin No. 73/1, Rome. 127pp.

FAO. 1990. Sericulture training manual. FAO Agricultural Services Bulletin, No. 80, Rome. 117pp.

FAO. 1993. Possibility of combined utilisation of Morus alba and Trifolium subterraneum in the Tuscan Maremma (Italy), p. 206-209. By P. Talamucci & A. Pardini. REUR Technical Series No. 28. Rome, FAO.

FAO. 1999. Mulberry, an exceptional forage available almost worldwide, by M.D. Sánchez. World Animal Review, 93(2): 36-46.

Gongfu, Zhong; Zengqi, Wang & Houshui, Wu. 1997. Land-water interactions of the dike-pond system. Namur, Belgium, Presses universitaires de Namur. 130 pp.

Huo, Yongkang. 2000. Mulberry cultivation in China. Proceedings of the electronic conference.

Janaki Ammal, E.K. 1960. The effect of Himalayan uplift on the genetic composition of the flora in Asia. JIBS, 39(3): 327-333. Cited by Sastry, 1984.

Katsumata, 1972. Mulberry species in West Java and their peculiarities. J. Sericultural Sci. Japan, 42(3): 213-223. Cited by Sastry, 1984.

Katsumata, 1973. Mulberry species in South Vietnam. J. Sericultural Sci Japan, 42(1): 81-88. Cited by Sastry, 1984.

Kitahara, N. 1999. Utilisation of fodder trees for the production of milk and meat (3). Livestock Res., 53(9): 969-972. (in Japanese)

Mehla, R.K., Patel, R.K. & Tripathi, V.N. 1987. A model for sericulture and milk production. Agricultural Systems, 25: 125-133.

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Sastry, C.R. 1984. Mulberry varieties, exploitation and pathology. Sericologia, 24(3): 333-359.

Ravindran, S., Ananda Rao, A., Girish Naik, V., Tikander, A., Mukherjee, P. & Thangavelu, K. 1997. Distribution and variation in mulberry germplasm. Indian J. Plant Genetic Resources, 10(2): 233-242.

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