Backyard integrated pig-fish culture in the Philippines
Integrated pig-fish culture is not a new concept; it has been practiced for many years in many parts of Asia. Raising pigs and fish at the same time has several advantages:
- Fish farmers can produce fish without feeding and hauling manure to fertilize the pond.
- Pig-fish culture maximizes land use by integrating two farm enterprises in the same area.
- The fishpond serves as a sanitary disposal place for animal wastes.
- Backyard integrated pig-fish culture provides additional income and a cheap source of animal protein for the family.
Establishing the system
1. Pond construction
- Establish the pond near a water source. However, the site should be free from flooding. Inlet and outlet pipes should be installed and screened.
- One pig can sufficiently fertilize a 100-150 mē pond with its manure. The water depth should be maintained at 60-100 cm. With this recommended pond area and water depth together with the right stocking density, problems of organic pollution are avoided.
- A diversion canal can be constructed to channel excess manure into a compost pit or when manure loading needs to be stopped.
- Nutrient-rich water from the pond can be used for vegetables grown on the pond dike or adjacent to the pond.
2. Location of the pig pen
There are two optional designs for locating the pig pen. It can be constructed on the dikes near the fishpond. Preferably, the floor should be made of concrete (or other impermeable material to catch pig manure and urine) and should slope toward the pond. A pipe is necessary to convey the manure and urine into the pond. An alternative design is to construct the pig pen over the pond. In this case, the floor can be made of bamboo slats spaced just enough to allow manure and urine to fall directly into the pond but not too wide for the feet of the pigs to slip into (thus, causing injuries). The pen should have a floor area of 1 m x 1.5 m for each pig.
- Stock the pond (approximately 100-150 mē) with fingerlings (200 fish/100 mē once it is filled up with water. Three optional fish culture systems are suggested here, of which Polyculture 2 is based on experience in Viet Nam and Thailand. Both polycultures contain predators to control tilapia recruits (if these are mixed-sex). The recommended stocking rates are as presented in Table 1.
- Stock the pig pen with one weanling (8-10 kg or 1.5 month old).
- Fish and piglets can be stocked at the same time.
4. Pig feeding
- Feed the pigs twice a day. Supplemental feeds such as kangkong (Ipomoea aquatica) may be given.
- Harvest the fish after 4-5 months. Collect fingerlings (if present) for the next growing season; sell the surplus. Partial harvesting for family consumption can also be done as needed.
- Sell the pig after 4-5 months.
- If possible, scrape out the organic waste or mud on the pond floor and use as fertilizer for the vegetable crop.
- High cost of inputs for pig growing (feeds and weanlings)
- Consumers may be reluctant to eat fish produced in manure- loaded ponds, creating potential marketing problems.
- Farmers want their animals close to their homes (because of theft problems) and this may not be always possible.
Table 1. Suggested stocking rates
Monoculture: 100% tilapia (Oreochromis niloticus) - 2 fish/mē, 3-5 g average weight
85% tilapia - 170 fingerlings, 3-5 g average weight
13% common carp (Cyprinus carpio) - 26 fingerlings
2% snakeheads (Channa striata) and catfish (Clarias batrachus) - 4 fingerlings,
1-2 g average weight
50% Pangasius micronemus - 100 fingerlings, 10 g
30% tilapia - 60 fingerlings, 3-5 g
20% kissing gourami (Helostoma temmincki) - 40 fingerlings, 1-2 g average weight
Possible solutions to overcome some of the limitations
1. Raise crossbred/native pigs to reduce feed cost.
2. Occasionally, fish from ponds, which were overloaded with manure, can have a «muddy» or off-flavour taste which can be removed through the following measures:
- Stop loading manure to the pond a few days before harvesting fish.
- Transfer harvested fish to a net enclosure installed in a clear pond at least 4-6 hours (better several days) prior to selling or eating them.
Cost and return (in Philippine peso) of the backyard
integrated pig-fish culture for a 5-month period
Rate of return on investment = 1 369.90/780 x 100 = 176%
Notes: 1. For P100 invested, the farmer gets P176.00
2. Entire capital cost can be recovered in one production cycle and still retain a surplus
3. 1992: US$1 = P26
Issues for further consideration
Given the better acceptance and adoption rates of this technology in other countries in Asia, there seem to be specific constraints to this in the Philippines. Pigs are resource-intensive and need a concentrate-based diet for them to grow and produce quality wastes for fishpond fertilization. Experiments have shown that leucaena (ipil-ipil) leaves can be toxic to pigs at relatively low levels. Growing crossbred pigs and native pigs can be fed lower-quality feeds but this does not necessarily result in overall lower feed cost per unit of pig weight produced. Growth is poorer and even if feeds are not purchased, effort and other resources are needed in their use. Pig production is often affected by marketing risks and problems, which should be considered by new entrants.
The scraping out of pond mud for crop and vegetable fertilization is labour-intensive and also requires a drained pond, which is not possible in many locations where rural fishponds have been sited.