INTEGRATED ANIMAL-FISH-MIXED CROPPING SYSTEMS

C. Devendra
Division of Agriculture, Food & Nutrition Sciences
International Development Research Centre
Tanglin P O Box 101
Singapore 9124

ABSTRACT

Integrated animal-fish-mixed cropping combining one or more animals is discussed in the context of relevance and the development of sustainable production systems. Two broad categories of systems are presently identifiable: (1) systems combining crops and ruminants (buffaloes, cattle, goats and sheep), and (2) systems combining crops, non-ruminants (pigs, chickens and ducks), ponds and fish. With specific reference to fish, the latter system is a time-honoured practice in which meager resources are effectively used interactively to maximise animal protein production. In recent years, recognition of the importance of other animals like ruminants, and different rates of production and quality of nitrogenous manure from them, has promoted efforts to explore the integration of both systems with fish production. The potential benefits are associated with increased efficiency in the use of the existing crop and animal resources, reduced dependence on purchased concentrates are used for feeding fish, and concurrent reduced cost of feeding and production. The efficiency of nitrogen utilisation for fish biomass production is relatively higher in systems where concentrates are used, however, the use of nitrogenous manure from animals has less pollution capacity. The implications for research are directly concerned with the development of more fully integrated systems in animal-fish-mixed farming that are distinctly more sustainable, provide for efficient resource use, are economically beneficial, and can promote environmental integrity. These aspects necessitate a clear systems orientation for their realisation and vigorous inter-disciplinary efforts.

INTRODUCTION

Integrated farming is common to most parts of Asia simply because of the preponderance of small farm systems which form the backbone of traditional agriculture. For small farmers, these systems enable a means of diversifying the use of meagre resources in the context of a rational means of reducing risk. Additionally, it also enables increased efficiency in the use of these same resources in a manner that there will be livelihood, security and stability to farming systems.

A variety of integrated systems have been used involving one or more animals throughout Asia. These can be broadly classified into two categories:

Systems Combining Crops And Ruminants

These are essentially terrestrial and are concerned with both perennial crops and animals, mainly ruminants (buffaloes, cattle, goats and sheep), in systems that do not involve the use of ponds.

Systems Combining Crops, Non-ruminants, Ponds and Fish

These systems directly involve the use of water, fish, mainly non-ruminants like pigs and ducks and also crop production such as vegetables and rice. Both types of systems have evolved fairly independently for a variety of reasons. The first category has until recently, seldom involved fish, whereas in the second category, the link with water has enabled easy integration between crops, fish, pigs and ducks, all of which have a special affinity for this resource. In both categories, the search is for practical technologies that can promote efficient use of natural resources, the interactions and interrelationships of which can also promote sustainable production systems.

These need to be identified with rural development processes in which the integrated systems developed are environmentally sound, technically appropriate, economically viable and socially beneficial to small farmers.

This paper examines the scope for integrating both systems, and in particular, how the second category can be broadened to include ruminants in integrated systems with fish.

TYPES OF INTEGRATED FISH SYSTEMS

There exist several types of integrated systems involving fish. These are briefly discussed.

Rice-Fish System

The specific focus on fish is historical and also commonplace since Asian farmers have been raising fish since time immemorial. Wild fish have been known to have entered flooded rice fields naturally, but this situation has been depleted due to reduced stocks of wild fish, fish diseases, toxic effects of chemical inputs and also degeneration for water resources. In recent years, these circumstances have shifted increased attention to research on the natural association between rice and fish, with considerable success. The advantages associated with this type of farming system are:

• reduced cost of rice cultivation through the removal of weeds, insects and pests that are consumed by the fish,
• increased fertilisation of the rice plants,
• provision of feed for fish, including the pollen from the rice flowers,
• increased production (rice and fish).

Integrated Pig-Duck-Fish-Vegetable Systems

The integrated system involving pig production, fish farming, duck keeping and vegetable production, or a combination of these (Devendra and Fuller, 1979) is traditional and widely practised in South East Asia and China. The inter-relationships between the component parts of the system are illustrated in Figure 1. The system is based on the use of ponds which not only meets the needs of pigs, but also enables fish and ducks to be kept. Water is also useful for vegetable production.

Integrated Systems Involving Various Animals

Unlike the traditional integrated system involving ponds and pigs-ducks-fish and vegetables that have been practised for centuries, the inclusion of ruminants into these is relatively new. There are several reasons for this, the chief the fact that ruminants, unlike pigs and ducks, are not normally reared concurrently with fish, adjacent to ponds by virtue of their orientation towards more extensive grazing systems in Asia. Secondly, extensive systems do not enable easy concentration and collection of dung in sizable amounts for use in fish ponds. This being possible only where animals are maintained in stall-fed systems. Thirdly, feedlots that provide a large supply of dung for use by fish are relatively uncommon in most parts of Asia; this further has not encouraged the development of integrated systems combining fish and ruminants. These reasons are reflected also in the very limited research into such systems, and associated with this, development of suitable methodology to promote such enterprises.

It is not surprising therefore that results from such integrated systems, and the effects of interactions of the components (crops, fish and individual animal species) are one of paucity. This has also not enabled identification of which animal species provides the best fit into such integrated systems, in individual situations, and in the long term, enable more specific research attention on the various factors that affect productivity, economic benefits and also contribute to sustainability. One of the few studies in this direction concerns integration of goats and ducks with fish in Malaysia. A 30–40 % increase in growth rate has been reported in this system in which also the performance of grass carp was more superior than that of big head carp (Mukherjee, 1985).

Complementary to the relationships between vegetable production and integration with pigs, fish and ducks, Figure 2 illustrates a parallel situation including ruminants. The reference to crop production refers mainly to annual types, examples of which are as follows:

Figure 1. Integrated pig-fish-duck-vegetable system.

Figure 2. Relationships between crop-animal interactions and fish production..

Table 1. Relative dung and nitrogen production in different animal species (per head/day).

In the ponds, several water weeds are invariably present, a very good example of which is water hyacinth (Eichornia crassipes) which has been used for feeding both pigs and also ruminants (Devendra, 1988). The special features of this type of integrated system are as follows:

• Complementary of ruminants to utilise nonmarketable crop residues in situ, the manure production from which can be used by fish;

• Availability of water plants which can also be simultaneously utilised by ruminants;

• Reduced cost of feeding and production due to more intensive use of available indigenous feeds. The use of purchased concentrate supplements is restricted to dairy cattle;

• Demonstrable benefits in terms of significant income generation from the sale of crops, animals, fish and some by-products like rice-bran in rice-based systems;

• Development of sustainable integrated systems combining fish and animals;

• With small farms, the meagre resources are put to more effective.

The future of such systems is dependent on the following factors:

• Demand for animal products and market outlets;
• Type of ruminant species, numbers and managements system (semi-intensive vs intensive);
• Type and quantity of available feeds, especially crop residues;
• Type of feeding system including pre-treatments and supplements;
• Access to availability of tree fodders for utilisation by ruminants, e.g., leucaena (Leucaena leucocephala), gliricidia (Gliricidia sepium) and sesbania (Sesbania grandiflora);
• Reduced availability of land for grazing and the development of more intensive stall-feeding systems;
• Access to ponds and water supply;
• Rising cost of feed and feed formulations.

The amount of dung produced by individual animal species as well as nitrogen (N) is mainly a function of type of species, size, age, sex, feeding regime and also health of animals. Table 1 provides an indication of the relative contribution by individual species on the assumption that their function in all cases is meat production and that they are stallfed.

It is clear that there are distinct qualitative and quantitative differences between the manures produced by individual species (Mueller, 1980). In particular, attention is drawn to differences in the N content in the faeces. With ruminants in general, the distribution of N in faeces and urine is approximately the same, but with non-ruminants, the percentage of N is higher in urine.

Smith, Calvert and Menear (1973) reported for instance that pigs and poultry had 33 – 67 % and 25 – 75 % of total N in faeces and urine respectively. Additionally, there is also the issue of differential rates of N breakdown between faeces. Goat manure for example has characteristics of biuret from which ammonia is distinctly more slowly released (Devendra, 1983).

Table 2. Estimated number of pigs, dairy cows and buffaloes required to produce the same yield, 174.7 kg of fish/200 m²/yr, as 26.7 ducks (extrapolated fish yield 8,735 kg/ha/yr and 1,335 ducks/ha), based on equivalent nitrogen manure inputs to the fish pond (Edwards, 1983).

PRODUCTIVITY OF FISH

In the light of the observations that nitrogenous manure inputs to ponds is dependent on several factors, it is clear that these will in turn influence the productivity of fish in ponds. Quantitative studies on this aspect are limited and in any case usually restricted to the involvement of individual animal species.

In an effort to overcome these influences as well as difficulties in comparing data from various workers, Edwards (1983) attempted to estimate the number of pigs, dairy cows and buffaloes required to produce a mean yield of 174.7 kg of fish/200/m²/yr from the manure of 26.7 ducks, equivalent to an extrapolated yield of 8735 kg/ha/yr from 1335 ducks. The number of animals required to produce this quantum of fish was 410 pigs, 40 dairy cows and 85 buffaloes. Table 2 presents the details of this calculation.

EFFICIENCY OF NITROGEN UTILISATION

Associated with limited information on the productivity of fish in different integrated systems, not very much is known about the efficiency of N utilisation in these systems.

Edwards (1991) has recently reported data on the relative N efficiencies in both intensive and semiintensive systems. In the former system N is supplied in the form of protein in complete pellet feed, and in the latter, N is supplied as fertiliser. The relative efficiencies for N converted into fish biomass are 21–53 % and 15–25 % in the intensive and semiintensive systems respectively, indicating a lower efficiency in the latter (Table 3).

Additionally, Edwards (1991) has calculated that based on N released into the environment, the integrated system has approximately 20–30 times less polluting capacity than an intensive system per kg of fish produced. This point is important since it further emphasises the value of integrated systems, together with reduced dependence on purchased concentrate feeds and concurrent reduced cost of feeding and production.

IMPLICATIONS FOR RESEARCH

The foregoing analysis suggests that there exists several important implications for research and development. These include inter alia:

1. Relevance and rationale for choice of animal component(s).

2. Interdisciplinary is especially useful to include inter-commodity participatory links between animal and fish scientists.

3. Increased efficiency of utilisation of existing meagre resources within small farm systems require carefully selected integration of the components (crops, animals and fish).

4. An understanding of the role of each component, interactions between them, and the development of methodology to support measurements. A strong systems perspective, complete with the different stages (diagnosis, design, testing and onfarm application and extension) will enhance research programmes.

5. The efficiency of utilisation of nutrients, and the relative contribution of the components of the system.

6. Socio-economic analysis is essential to provide diagnosis of the circumstances and changes, to include the elements of processing, utilisation and marketing.

7. The systems approach will also enable an assessment of sustainability, environmental effects as well as economic impact.

Table 3. Nitrogen efficiencies in a theoretical intensive system and experimental semi-intensive systems (Edwards, 1991).

REFERENCES

Devendra, C. (1981). Non-conventional feed resources in Asia and the Pacific. APHCA/FAO Publ. No. 7. FAO Regional Office for Asia and the Pacific, Bangkok, Thailand, viii + 151 pp.

Devendra, C. (1983). Goats: husbandry and potential in Malaysia, Bull. No. 158, Ministry of Agriculture, Malaysia, Kuala Lumpur, iii + 177 pp.

Devendra, C. and M. Fuller. (1979). Pig Production in the Tropics. Oxford University Press, Oxford, England, xii + 172 pp.

Edwards, P. (1983). The future potential of integrated farming systems in Asia. Proc. V World. Conf. Anim. Prod., Vol. 1: 273–281.

Edwards, P. (1991). Integrated fish farming. INFORFISH Int., 5: 45–52.

Mueller, Z.O. (1980). Feed from animal wastes. FAO Anim. Prod. Hlth Paper, No. 18 xi + 190 pp.

Mukherjee, T.K. (1985). Integration of aquaculture and livestock farming; an experiment of study for rural development. Proc. II Asian Conf. on Technology for Rural Development, Kuala Lumpur, Malaysia, p. 377–391.

Smith, L.W., Calvert, C.C. and J.R. Menear. (1973). Dehydrated poultry manure as a protein supplement for sheep. Proc. Md. Nutr. Conf. p. 35–42.