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ANNEX C
Integrated Livestock-Fish Farming in India

V.G. JHINGRAN
AND
B.K.SHARMA

Central Inland Fisheries Research Institute
Indian Council of Agricultural Research
Barrackpore 743 101, West Bengal, India

Abstract

The integration of fish culture with livestock rearing holds great promise and potential for augmenting production of animal protein, betterment of the economy, and generation of employment in rural India. Until recently, however, no worthwhile attempt was made in this direction even though 80% of the country's population live in villages, and are undernourished and in urgent need of gainful employment.

The work done on pig-fish farming and duck-fish farming in India is described and the results obtained, including the economics of integrated systems, are compared with those of modern semi-intensive fish culture. Integrated farming systems involving fish production have opened up new horizons of high animal protein production at very low cost. Fish yields of 7,300 kg/ha/yr and 4,323 kg/ha/yr were achieved for pig-fish and duck-fish farming, respectively. The pig and duck manure replaced fish feed and pond fertilizers. The costs/kg of fish produced were Rs1.07 (pig-fish) and Rs1.61 (duck-fish). The raising of ducks on a fish pond fits very well with the ecological niche concept of polyculture: the unutilized surface water niche in fish culture becomes occupied.

The possibilities of combining horticulture and fish culture by growing vegetables, fruit trees, and cattle fodder on the terraced embankments of ponds and using pond detritus as fertilizer are also discussed.

Introduction

About 80% of India's population live in rural areas at subsistence or near subsistence level. These rural folk are greatly undernourished and need not only a large supplement of animal protein to their diet but also new sources of gainful employment. Fish culture could contribute substantially towards solving these crucial problems, but no worthwhile impact in this direction has been made so far because of the various constraints against the adoption of existing high-yielding aquaculture technologies. One of the most serious constraints is the high cost of inputs, especially fish feed and pond fertilizers. This cost can be reduced considerably and fish production increased by combining fish culture with raising livestock. If livestock, such as pigs, ducks and poultry, are raised on pond embankments and the fish utilize the waste animal feeds and animal excreta, then fish production can be greatly enhanced by the increase in the biological productivity of the water. Supplemental feed and fertilizers are not needed in such a system and the cost of inputs is therefore reduced.

Integrating fish culture with livestock raising has been well-developed in China, Hungary, Germany, Malaysia and certain other countries (Hickling 1960; Wolny 1966; Ling 1971; Tapiador et al. 1977; Woynarovich 1979).

Little attention has been paid to the recycling of animal wastes through fish production in India, but cattle manure is used for fertilizing fish nursery, rearing and stock ponds (Alikunhi 1957; Sharma 1974; Jhingran 1974). Attempts have also been made in recent years to combine livestock raising with fish culture and to standardize the number of animals required per unit of water area for adequate manuring and high fish yields in the absence of fertilizers and supplemental feed. The integration of pig and duck farming with fish culture was attempted for the first time in India in District Nadia, West Bengal (Sharma et al. 1979a, 1979b).

The work done so far in India on the integration of livestock raising with fish culture is presented in this paper.

Pig-Fish Farming

POND MANAGEMENT AND HARVESTING

An experiment was conducted in a 0.1-ha pond, situated in a 5-ha agricultural farm owned by the Don Bosco Society, Krishnagar, District Nadia, West Bengal. The water remained static, with no circulation or aeration, and the average depth was 3 m. Existing pigsties, situated a little away from the pond, were used, but due to the lack of drainage channels, the urine and washings from the pigsties could not be added to the pond. The existing stock of fish in the pond was first removed by poisoning with Mahua (Bassia latifolia) oil cake at 250 ppm. Lime was also applied 15 d before poisoning at 200 kg/ha.

The pond was stocked in January 1977 with fingerlings of the Indian major carps, catla (Catla catla), rohu (Labeo rohita), mrigal (Cirrhina mrigala); the Chinese carps-the silver carp (Hypophthalmichthys molitrix) and the grass carp (Ctenopharyngodon idella)-and the common carp (Cyprinus carpio) (Table 1).

Pig manure was collected from the pigsties, weighed and dumped in heaps at the four corners of the pond each morning. No supplemental fish feed or fertilizers were used other than chopped green cattle fodder, which was given to the grass carp. This was grown on the terraced embankments of the pond, together with lettuce and spinach, and other crops such as papaya, bananas and coconuts. No aquatic vegetation was provided for the grass carp. The pond bottom was raked once every week to release any gases. Lime was applied four times during the course of experiment at 200 kg/ha/application.

The dissolved oxygen (DO) and biochemical oxygen demand (BOD) of the pond water were monitored and the quantity of manure added regulated accordingly. The DO ranged from 3 to 6 ppm and the BOD from 4.08 to 9.05 ppm.

Table 1. Yields of fish and pigs from an integrated farming experiment at the Don Bosco Agricultural Farm, Krishnagar, District Nadia, West Bengal, India, using a 0.1-ha fish pond stocked with a total of 850 fish and a culture period of 12 mo.

1. Fish
SpeciesAverage weight at stocking (g)Composition of stock (%)Average weight at harvest (g)Total weight harvested after 12 mo (kg)Survival
(%)
Contribution to total yield (%)
atla48201,100120.75064.116.5
Rohu28201,000  95.60055.813.1
Mrigal2320   809  77.74056.410.6
Silver carp  9152,100219.00080.430.0
Grass carp  5201,300191.80085.226.2
Common carp  3  5   450  25.75083.3  3.5
  Total yield      730.640 kg  

2. Pigs
No. of piglets
for fattening
Average initial
weight (kg)
Period of
growth (mo)
Average finished
live weight (kg)
Total weight
(kg)
First group
8
22.5895.4763.200
Second group
5
25.0466.5332.500
   Total yield1,095.700 kg

The pond was harvested after 12 mo and yielded 730 kg of fish. All the species stocked showed good growth rates (Table 1).

PIG HUSBANDRY

Two groups of Landrace piglets were raised during the course of experiment: the first group (8 piglets) for 8 mo and the second group (5 piglets) for 4 mo. The pigs were confined to the pigsties and fed on pig mash concentrate at an average rate of 1 kg/pig/d. Green grass or green cattle fodder was also fed every day and sod (turf with soil) provided once a week to prevent mineral deficiency. This diet kept the pigs in a healthy condition and hygiene was of a high standard. Table 1 gives the initial and final weights of the pigs.

ECONOMICS

Details of the input costs and returns for fish culture and pig raising are given in Table 2. The fish were sold at the farmgate. The costs of production/kg were Rs1.07 for fish and Rs4.15 for pigs (US$1.00 = Rs 8.00).

Table 2. Input costs and returns for a year's production of fish and pigs from an integrated farming experiment using a 0.1-ha pond at the Don Bosco Agricultural Farm, Krishnagar, District Nadia, West Bengal, India (US$1.00 = Rs 8.00).

A. Fish   
 1. Input costsQuantityUnit cost or value
(Rs)
Total cost or value
(Rs)
  Mahua cake (Bassia latifolia)800g0.41/kg331.20
  Fingerlings850 fish8.25/kg136.94
  Lime100 kg0.24/kg24.00
  Potassium permanganate1 kg21.40/kg21.40
  Labor, netting, etc.--170.00
  Pond rental0.1 ha1,000/ha/yr100.00
    Total783.54
 2. Returns   
  Fish sales730.64 kg7.62/kg5,567.48
B. Pigs   
 1. Input costs   
  Piglets (first group)8 (180 kg)5.50/kg990.00
  Feed1,976 kg1.00/kg1,976.00
  Piglets (second group)5 (125 kg)5.50/kg687.50
  Feed690 kg1.00/kg690.00
  Green fodder, etc.--104.00
  Depreciation cost of pigsties-construction cost, Rs 3,000; life expectancy, 30 yr-  
    Total4,547.50
 2. Returns   
  Sale of pig meat1,095.70 kg5.50/kg live weight6,026.35

C. Summary 
 Total operational costs= Rs 5,331.04
 Interest on working capital at 10%= Rs 533.10
  Total variable costs= Rs 5,864.14
 Total returns= Rs 11,593.83
 Net profit= Rs 5,729.69
 Net profit as a % of total variable costs= 98%

Duck-Fish Farming

POND MANAGEMENT AND HARVESTING

A 1.48-ha rectangular pond was used with average depth of 1.5 m, but rising to 2.5 m during the rainy season. The pond was prepared for fish stocking as described above.

The pond was initially stocked in January 1977 (Table 3). After partial harvesting in October 1977, however, a second stock of catla fingerlings was added to the remaining stock and the percentage species composition became catla, 12%; rohu, 13%; mrigal, 27%; silver carp, 12%; grass carp, 11%, and common carp, 25%.

During the daytime the duck manure was spread on the pond by the ducks themselves. Manure produced at night was collected from the duck houses and added to the pond. No supplemental feed or fertilizer was used, but lime was applied twice during the course of the experiment at 250 kg/ha/application.

The pond was harvested twice during the one-year experiment: partial harvesting after 9 mo and final harvesting after 12 mo. The total yield was 6,397 kg, which corresponds to 4,323 kg/ha/yr. The details of growth, production, survival and contribution by various species are shown in Table 3.

DUCK HUSBANDRY

One hundred Khaki Campbell-Bengal runner cross ducklings were reared over the pond. They were allowed to range freely over the water by day and sheltered at night in a floating duck house made of bamboo matting over empty oil drums, positioned close to the pond bank. The ducks depended initially on the natural food available in the pond, but were fed 100 g/head/d of balanced poultry feed from August 1977, supplemented with chopped aquatic weeds (e.g., Hydrilla and Potamo-geton) and occasionally with molluscs. In July 1977, some of the ducks died due to an unspecified disease, and were replaced by fresh ducklings.

After attaining maturity, the ducks laid 1,835 eggs. They attained an average weight of 2.5 kg after 12 mo. A total of 250 kg of ducks (live weight) for consumption was also produced (Table 3).

Table 3. Yields of fish and ducks (eggs and live weight for meat) from an integrated farming experiment at the Anjana fish farm, Krishnagar, West Bengal, India using a 1.48-ha pond stocked with a total of 9,400 fish (6,340/ha) harvested after 9 and 12-mo growth periods (for catla alone, a second stocking was made after the 9-mo harvest-see text).

1. Fish
SpeciesAverage initial
weight (g)
Composition of
stock(%)
Growth period
(mo)
Average weight
at harvest (g)
Total weight
at harvest (kg)
Survival
(%)
Contribution to
total yield (%)
Catla       
First stocking43109904801.15096.319.2
Second stocking  3498429.300  
Rohu28189413346.50090.613.1
   12633488.650  
Mrigal23289495305.80072.615.4
   12513677.300  
Silver carp  51591,643632.00094.230.2
   121,9201,300.300  
Grass carp  510121,7201,092.00076.817.1
Common carp  51912206161.20053.1  2.5
Miscellaneous----163.100-  2.5
   Total yield          6,397.300 kg 

2. Ducks
No.of ducklings raisedAverage initial weight (g)Growth period
(mo)
Average finished weight (kg)Total finished weight (kg)No. of eggs produced
100250122.5002501,835

ECONOMICS

Details of the input costs and returns for fish culture and duck raising are shown in Table 4. The cost of production for fish was Rs1.61/kg. The fish were sold at a fixed government price of Rs5.50/kg as against the prevailing farmgate price of Rs8.00/kg by deliberate policy to make them available to local consumers. The eggs were also sold at a very low price (Table 4). The ducks were not sold at the end of the experiment.

Chicken-Fish Farming

Integration of fish culture with chicken farming has only recently been initiated in India and few results are available. Research on the fertilizing efficiency of chicken manure in fish ponds, either alone or in combination with cattle manure, has been done by Banerjee et al. (1969), who observed that a combination of chicken and cattle manure worked better than the cattle manure alone in fertilizing nursery ponds. It has also been reported that poultry manure is a complete fertilizer, with the characteristics of both organic as well as inorganic fertilizers (Banerjee et al. 1979). Ray and David (1969) found that chicken manure produced a large population of rotifers quicker than cattle manure. A fish yield of 670 kg/ha/90 d has been reported by Banerjee et al. (1979), using poultry manure and no supplemental feeds.

Table 4. Input costs and returns for a year's production of fish, duck eggs and ducks sold for meat from an integrated farming experiment at the Anjana fish farm, Krishnagar, West Bengal, India using a 1.48-ha pond stocked at 6,340 fish/ha (US$1.00 = Rs 8.00).

A. Fish    
 1. Input costsRate/haQuantityUnit cost or value
(Rs)
Total cost or value
(Rs)
  Mahua cake (Bassia Latifolia)    250 ppm6,400 kg0.38/kg2,432.00
  Lime250 kg372.5 kg0.30/kg111.75
  Fingerlings6,340       9,400    -2,506.75
  Insecticide (BHC)    1 kg     1.5 kg7.50/kg11.25
  Netting and other miscellaneous costs---997.51
  Labor (security and fish handling)-  2,761.54
  Pond rental-   1.48 ha1,000.00/ha/yr1,500.00
     Total10,320.80
 2.Returns    
  Fish sales 6,397 kg5.50/kg*35,183.00
B. Ducks    
 1. Input costs    
  Ducklings 140  approx 9.00/head1,272.00
  Poultry feed 1,510 kg        1.00/kg1,510.00
  Medication --97.00
  Depreciation cost of floating duck house-contribution cost, Rs 2,500; life expectancy, 5 yr    500,000
     Total3,379.00
 2. Returns    
  Egg sales 1,835      0.40/egg*734.00
  Ducks for meat 250 kg (live weight)10.00/kg2,500.00
     Total3,234.00

C. Summary 
 Total operational cost=Rs 13,699.80
 Interest on working capital at 10%=Rs   1,369.98
  Total variable costs=Rs 15,069.78
 Total returns=Rs 38,417.00
 Net profit=Rs 23,347.72
 Net profit as a % of total variable costs=155%

Discussion

Experiments on integrated livestock-fish farming have opened up a new horizon of high animal protein production at very low cost. Besides providing cheap protein-rich food, integrated farming has proved to be an efficient means of waste disposal and has allowed savings on the use of inorganic fertilizers and supplemental feeds in fish production.

The yield of 7,300 kg/ha/yr from the pig-fish experiment, without the use of any supplemental feeds or inorganic fertilizers, is high compared to the average yields of 3,543 kg/ha/yr, achieved through polyculture with intensive feeding and fertilization in the Eastern region of India (Anon. 1977); 4,290 kg/ha/yr from Krishnagar, West Bengal (Sharma et al. 1978); 4,250 kg/ha/yr from District Nadia, West Bengal (Murshed et al. 1977) and 3,232 kg/ha/6 mo at Kalyani, West Bengal (Sinha et al. 1973). The yield from the present experiment is also significantly higher than the yields obtained from pig-fish rearing in other countries, e.g., in Illinois, U.S.A., 3,625 and 4,140 kg/ha/yr with polyculture of Chinese carps (Buck et al. 1979); 3,667 kg/ha/yr in Penang (Le Mare 1952) and 5,500 kg/ha/yr in France (Bard et al. 1976).

The fish, besides consuming the large amounts of natural food produced in the pond, were also observed to feed directly (especially the bottom feeders) on pig manure (Sharma et al. 1979a). Maar (1956) has reported that pig manure contains 70% digestible food for fish. Le Mare (1952) observed that the food, while passing through the alimentary canal of the pig, gets mixed with certain enzymes which continue to digest the manure even after voiding. Manure therefore has high food value for fish.

About 2,000 kg of pig manure was recycled in the 0.1 ha pond during the 12 mo experiment. One pig voids from 550 to 600 kg manure in one year and therefore about 35 to 40 pigs would be sufficient to fertilize 1 ha of water. These observations are in close agreement with pig-fish farming practice in China, where 35 to 45 pigs/ha are used (Tapiador et al. 1977).

In India, pig-fish farming has a special significance, as it can improve the socioeconomic status of many of the weaker rural communities, especially the tribal communities which traditionally rear pigs. Demonstrations of the technology, financial assistance and water areas must, however, be provided. According to a 1972 livestock census, the pig population in India was 6.5 million (Anon. 1976), which is sufficient to bring 0.16 million ha of water into pig-fish farming.

The fish yield of 4,323 kg/ha/yr from the duck-fish experiment, without the use of any supplemental feed or inorganic fertilizers, is also high compared to the yields of 4,290 kg/ha/yr, obtained from the same pond during 1973 to 1974 (Sinha and Sharma 1976; Jhingran and Sharma 1978; Sharma et al. 1978); 3,543 kg/ha/yr in Eastern India (Anon. 1977), and 4,258 kg/ha/yr from District Nadia, West Bengal (Murshed et al. 1977), which were achieved with heavy supplemental feeding and fertilization. The present yield is also higher than that from duck-fish farming in Taiwan: 3,500 kg/ha/yr (Ling 1971).

The raising of ducks on fish ponds fits very well with the ecological niche concept of polyculture. In conventional polyculture, the major niches are all occupied by various species of fish, except for the water surface niche which is unutilized. The ducks consume such organisms as tadpoles, mosquitos, larvae of dragon flies and other insects, molluscs and aquatic weeds, and thus do not compete significantly with the fish for any food items commonly found in conventional polyculture of carp. Their manure fertilizes the pond, and their disturbance the substrate, while feeding, helps to release nutrient from the soil and further increases fish production. By day, the ducks distribute their manure over the whole pond area.

The polyculture ponds described here for integrated farming lack any aquatic vegetation and the ducks therefore depend mostly on feeding by man. The number of ducks should be kept to an easily manageable number, just adequate for pond fertilization. In the present experiment, 100 ducks provided approximately 10,000 kg of manure over 12 mo. The results and experience obtained suggest that 100 to 150 ducks can give adequate fertilization of 1 ha of water. This is comparable with the recommendation of Behrendt (1978): i.e., 300/ha average and 100/ha where natural food is limited.

The duck population in India has been estimated at 10 million (Anon. 1976). Ducks are mostly concentrated in Tamil Nadu, Kerala, Assam, Orissa, West Bengal and Bihar. They are mainly used to produce eggs. The surplus drakes and ducks which are too old for laying are used for meat. These states also have great potential for fish culture and could greatly increase their animal protein production by integrated duck-fish farming.

Ducks are likely to eat small fish and should be excluded from nursery ponds. Fingerlings of 10 cm or over are recommended for stocking in duck-fish systems.

The chicken population of India has recently been estimated at about 136 million (Anon. 1976) and the integration of chicken farming and fish culture, if developed on scientific lines, could also help solve the animal protein deficiency problem of the country and generate employment opportunities for the rural poor.

Integrated livestock-fish farming not only increases fish production but also cuts down the cost of fish culture operations considerably. The average cost of production in conventional polyculture with supplemental feeding and inorganic fertilization was Rs 2.93/kg in Eastern India (Anon. 1976). Murshed et al. (1977) have also recorded Rs2.67/kg as the cost of fish production by conventional methods in District Nadia, West Bengal. The present costs of production of Rs1.07/kg (pig-fish) and Rs1.61/kg (duck-fish) are much lower.

The annual profits made from pig and duck farming are not very impressive, but the total income from an integrated farming system must be considered to assess economic viability. The waste materials, i.e., pig dung and duck droppings, act as a substitute for supplemental fish feed and fertilizers, which in conventional fish culture account for 58.6% of the total input cost (Anon. 1977). The expenditure incurred by raising ducks and pigs is largely offset by the sales value of pig meat, eggs and duck meat. The percentage returns on total variable costs of 98% (pig-fish) and 155% (duck-fish) would give enough income not only for the maintenance of the farmer's family but also some spare capital for enlarging his scale of operations.

The gap between the demand and supply of inorganic fertilizers is increasing every day due to intensive cropping of the high yielding varieties of cereals. The recycling of organic wastes, through integrated farming systems, can help solve this problem. The cattle fodder, vegetables, and fruit crops grown on the terraced embankments of the pond, which are not normally utilized in the fish culture operations, provided fodder for the grass carp and pigs and extra income to the farmer. The organic detritus removed from the pond bottom can also serve as an efficient fertilizer for growing land crops. This opens up possibilities of combining horticulture and fish culture.

While integration of livestock farming with fish culture gives high yields at low cost, the systems require effective management. One of the problems is the difficulty in combining and balancing the expertise needed in fish and animal husbandry. Overconcentration on one may work to the detriment of the other. Monitoring the DO and BOD of the pond water is absolutely essential as a thick organic sediment settles at the pond bottom, which hastens the depletion of oxygen and enhances the production of toxic gases, and can result in fish kills. The application of manure should be regulated according to the pond water DO. The pond should also be desilted when a significant amount of detritus has accumulated at the bottom.

Animal excreta are a potential source of infection for various parasites and diseases. Studies are being made to investigate the possible human health hazards from integrated livestock-fish farming systems. Obviously, the livestock should be maintained in good health and under hygienic conditions.

References

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