Category: AGRICULTURE

African Catfish farming – part 2

Catfish farming as a livelihood 

According to him, catfish fingerlings  should be stocked in grow-out ponds and given a daily fare of high protein feeds like trash fish, golden kuhol, and chicken innards.

“The amount of feed should be just about right for the fish population,” he said. “Give too much and you will pollute the water, As with other types of fish, the two most important things about raising catfish in grow-out ponds is maintenance of water quality and proper feeding. If you do these two things right, you can’t fail.”

Before we left his house in Imus, Cavite, Madlangbayan gave us the pamphlet which he distributes to the farmers who buy his catfish fingerlings. The pamphlet was in Tagalog. We have translated it into English and are reproducing it below for use as a guide by the country’s catfish farmers.

 

How to raise African catfish (Clarius gariepinus)

Preparing excavated ponds. The size of the pond depends on the operator, but  the ideal size is 200 to 1000 square meter. The depth should be one meter or deeper. The dikes or embankment around the pond should be at least 50 centimeters wide. The sides should be surrounded by a fish net to protect growing catfish from predators.

Water should enter the pond from an inlet in a corner of the pond and should flow out in an outlet in the corner opposite the inlet. This will ensure the maintenance of good water quality. There should be a net at  the outlet to prevent the escape of fish.

Preparing embankment or cement ponds. Cemented ponds need to be provided with an aerators to augment the oxygen supply of the water. Oxygen  depletion is a common phenomenon in cemented tanks; hence, there may be a need to constantly add water to the pond. The operator should also add kangkong or water lily in the water to give fish refuge from intense sunlight.

All the other steps in excavated pond preparations should be followed.

Caring for the catfish. The stocking density should be 10 cat fish per square meter. The operator can increase this population if there is constant water exchange and replenishment or if the water quality is very good.

“The fish should be fed twice a day – once in the morning and once in the afternoon. The amount of feed depends on the size of the fish. On the average, 100 pieces of fish should receive one and a half kilograms of feed daily. Feed the fish on the same spot daily.

Do not overfeed the fish. Overfeeding may result in the deterioration of water quality and will make the fish vulnerable to parasites and diseases.

The following are good feed for catfish: fish(roundsead or galungong, dilis, etc.) trash fish, fish entrails, pig and chicken intestines, golden apple snails or golden kuhol, termites worms, and insects.

Changing the water in the fishpond should be undertaken gradually to avoid stressing the fish.

Polyculture of catfish and tilapia. You can grow catfish and tilapia at the same time in the same pond. The stocking density should be three catfish and two tilapia per square meter. Follow the feeding schedule outlined above. Tilapia multiples fast and the fingerlings they produce  can serve as food for the growing catfish.

Other information about the African catfish. The price of catfish fingerlings depends on their size. The fish grow rapidly and are easy to raise and can be harvested two to three months after stocking in grow-outponds.

Depending on the water quality and management there will be tow to four pieces per kilogram of catfish at the time of harvest. Some farmers have harvested five kilogram specimens.

The flesh of the fish is soft unlike that of the Thai catfish or Clarias batrachus, which is tough and leathery.

The African catfish could be the basis for good and profitable livelihood project.

Source: Greenfields, April 1993

African Catfish farming – part 1

Catfish farming as a livelihood

 

This fish is called African catfish or Clarias gariepinus said catfish breeder Berting Madlangbayan of Bayan Luma, Imus Cavite. “It’s flesh is as soft and delicious as that of native catfish. But this fish is larger than native catfish. If properly fed and stocked in ponds with well-managed water, it will grow to 500 grams in two and a half to three months.”

Madlangbayan has a commerce degree (1965) and is a  “farmer at heart.”  He has been a fishpen operator in Batangas where he suffered a  series of business setbacks , has worked at the Bank of Philippines Islands, and has attended a number of seminars on fish breeding , production and management. In 1990, he started the difficult task of inducing catfish to spawn, a highly experimental field where even many fisheries experts have failed.

Hard work, dedication and bold experimentation have paid off. He succeeded in developing a reliable method of inducing Clarias gariepinus to spawn.

For business reasons, Madlangbayan said he could give Greenfields readers only a general outline of the breeding method that he uses.

“I uses eight-month to one year-old breeder fish that have been stocked in tanks with clean, deep well water,” he said. “I can quickly identify ready to spawn female catfish from their distended or swollen bellies.

“Next, I inject a commercial spawning hormone that has been properly mixed with a culture medium into the testes or muscle of the fish. I use about 0.5 ml of this solution for every fish. The injection process is a delicate one: you have to hit the right muscle so that the hormone could be conducted to the pituitary gland of the animal this induces it to spawn. If done correctly the female will spawn 10 to 20 hours after the injection.

If hormone mixing and the injection are not done right, he added there will be delayed spawning or no spawning at all.

Madlangbayan said he could not reveal the precise details of the process (the correct mix of hormone with culture medium and other things) because he’s in business and every businessman should have a few trade secrets up his sleeve to stay ahead of competition.

We said we understood his position perfectly and did not press him for details.

The fry that develop eat their own yolk sac for five days and then are given a pure protein feed by Madlangbayan’s workers. They are then transferred to a nursery where, for five to seven days, they receive a high protein feed formulation.

Madlangbayan has perfected his spawning method and now produces about 500,000 catfish fingerlings monthly. He sells them to catfish farmers from Pampanga , Bulacan, and Laguna.

 

The papaya – part 2

The Papaya 

Papaya is rich in an enzyme called papain, a protease that is useful in tenderizing meat, and other proteins. Its Utility is in breaking down  the tough meat fibers and it has been utilized for thousands of years in its native South America. It is included as a component in powdered meat tenderizers. Papaya enzyme is also  marketed in tablet form to remedy digestive problems. Papain is extremely useful since it retains proteolytic activity over a wide pH range, unlike other proteases. Thus, it is in more widespread use than bromelain, the proteolytic enzyme found in pineapple juice. Latex is extracted on a commercial scale in East Africa, where the green fruit are “tapped” by making incisions on the fruit surface in the morning, and catching the exuding latex over a period of days. The latex is then dried, and ground into powder. The most popular use is a meat tenderizer.

 

The black seeds are edible, and have a sharp, spicy taste. They are sometimes ground up and used as a substitute for black pepper. The papaya is high in digestive properties and has a direct tonic effect on the stomach. It is used in the treatment of stomach ulcers and fevers, and has a high mucus solvent action.

 

All organs of the plant contain laticifers, and white latex flows freely from any cut surface. Long ago, natives learned that papaya latex is a very effective meat tenderizer. Tough meat was wrapped in fresh leaves for several hours to make it tender. The active tenderizing ingredient is a protein-digesting enzyme called papain, which is very similar to human stomach pepsin. Interestingly, some of the early crude studies of plant protein structure   were done by digesting the proteins into pieces with the use of papain.

 

When choosing a papaya, look for one that is fairly large, half yellow or more, and slightly soft. It should yield to gentle palm pressure. Avoid papayas that are too soft, or those that have scars or blemishes.

 

If the skin has no yellow, the papaya will ripen if left at room temperature for a few days. If a papaya is less than half ripe, do not store it in the refrigerator. Cool temperatures shut off the ripening process. A papaya that is one-quarter to one-half ripe should keep for one to two weeks. Completely ripe papayas should be refrigerated and eaten as soon as possible.

 

Papain has been commercially produced by scoring unripened fruits with longitudinal cuts and then collecting the copious latex in containers set on the ground below. The latex is sun- or oven-dried into a powder; the papain powder most commonly is marketed in the United States as Adolph’s Meat Tenderizer. Much of the papain is produced  in Tanzania. There are a variety of other uses for this interesting enzyme, which is fairly similar to another proteolytic enzyme found in pineapple, bromelin.

 

As we can see the uses for papain are diverse and thus it makes it an extremely valuable enzyme. Papain has been employed to treat ulcers, dissolve membranes in diphtheria, and reduce swelling, fever and adhesions after surgery. With considerable risk, it has been applied on meat impcted in the gullet, chemopapain is sometimes injected in cases of slipped spinal discs or pinched nerves, Precautions should be taken because some individuals are allergic to papain in any form and even to meat tenderized with papain.

 

As medicinal product, papain is used in some localities to remedy gastrointestinal and similar ailments. The ripe fruit, when eaten fresh, improves food digestion and is reported to have a complimentary laxative effect.. Its proteolytic enzymes work together to break down  complex proteins to produce small peptides and amino acids that cn be better utilized or transported to other parts of the body. One focus of contemporary biomedical research is determining the most appropriate  applications of these bioreactive natural papaya plant products.

 

Benefits or uses of Papaya include

Digestive enzyme for protein

Tonic effect on the stomach

Has solvent effect on mucous

Disinfectant

Helps stomach ulcers

Aids in fevers

 

The papaya is a good source of vitamins A and C, as well as folate and fiber. In addition, it’ fat-free. Cholesterol-free and low in sodium. And an average serving (1/2 papaya) has only 70 calories.

 

Source:biolife magazine September-october 2008

The papaya – part 1

The papaya

 

Papaya are native to Central America.

Thee are two varietes of papayas, the Hawaiian papaya is the most common variety and may weigh one pound each, and less common Mexican Papaya which can weigh up to 15 punds. They are available all year. Papayas are known for their enzyme, papain, which is the basis for many meat-tenderizing products on the market.

 

Papaya have exacting climate requirements for vigorous growth and fruit production. They must have warmth through the year and will be damaged by light frosts. Brief exposure to 32 Fahrenheit is damaging and prolonged cold without overhead sprinkling will kill the plants. Cold, wet soil is almost is almost always lethal. Cool temperatures will also alter fruit flavor. Papayas make excellent container and greenhouse specimens where soil moisture and temperature can be moderated.

 

It is believed that the papaya originated in southern Mexico, Central America, or West Indies. Now widely cultivated in tropical and subtropical countries, there are about 45 species of papaya. The most common variety in the United States is the Solo papaya, which is grown in Hawaii and Florida. Mexican Papaya are much larger than the Hawaiian types and may be more than 15 inches long.

 

The papaya is considered to be one of the healthiest fruits to eat and to some the most nutritious fruit of all. In 1992, the Center for Science in The Public Interest (CSPI) a Washington based consumer group that studies nutrition, compared 40 fruits for their overall healthfulness. Based on a point system awarded to each fruit for the RDA percentage of the nine individual vitamins plus estimations for potassium and fiber, the papaya was number one,  followed by cantaloupe, strawberries, oranges, and tangerines. Papayas are not only nutritious they are also delicious.