CATDOLL : CATDOLL: What do tilapia eat?

What does tilapia eat to grow?

Tilapia is an omnivorous fish that mainly feeds on plants. The digestive tract contents of tilapia in ponds are mostly organic debris and other plant feeds (such as aquatic plants, commercial feeds, etc.), followed by phytoplankton, zooplankton and a small amount of benthic animals.

When tilapia is raised artificially, it can be fed 2 to 3 days after entering the aquaculture water surface. Under artificial breeding conditions, various feeds can be fed, such as wheat, corn, cake meal, etc., which are all high-quality feeds.

The protein content in the feed should be 32% to 35% at the beginning. When the individual size grows to about 200 grams, the feeding amount can be adjusted to 2% of the total weight of the fish, and the protein content in the feed should be guaranteed to be 27% to 29%. When the individual reaches about 300 grams, tilapia enters the fastest growth period.

Additional information:

Reproductive capacity

Tilapia matures early, has a short spawning cycle, and hatches young fish in its mouth. It does not require high breeding conditions and reproduces naturally in large areas of static water. Tilapia reaches sexual maturity at 6 months old, and a female fish weighing about 200 grams can carry about 1,000 to 1,500 eggs.

During the breeding period, the male fish has beautiful nuptial colors, and two openings on its abdomen: the anus and the urogenital opening. White semen flows out when the abdomen is squeezed. The female fish has three holes on its abdomen: the anus, the genital opening, and the urinary opening.

When the water temperature is 18-32℃, the mature male fish has the ability to "dig a nest". The mature female fish enters the nest to mate, produces mature eggs and immediately holds them in the mouth to fertilize them. The fertilized eggs develop in the female fish's mouth. When the water temperature is 25-30℃, the young fish can hatch in 4-5 days. The young fish leave the mother's body when the yolk sac disappears and has certain abilities.

Wheat, corn, cake and meal are all high-quality feeds. Tilapia has a wide range of diets and can be fed with a variety of feeds under artificial breeding conditions.

When feeding tilapia, the protein content in the feed should be 32% to 35% at the beginning, and the daily feeding amount should be 3% to 5% of the total weight of the fish. When the individual size grows to about 200 grams, the feeding amount can be adjusted to 2% of the total weight of the fish, and the protein content in the feed should be 27% to 29%. When the individual reaches about 300 grams, tilapia enters the fastest growth period, and the daily feeding amount is maintained at 1% to 2% of the fish body weight, and the protein content in the feed is above 35%.

Tilapia should be fed twice a day, and the amount of food should be enough for the fish to eat within 30 minutes.

Tilapia should be fed with appropriate green fodder (red duckweed, ryegrass, etc.) every day, and the green fodder should be controlled at about 0.3-0.5% of the body weight of the fish in the pond. It is best to use granular bait, and the bait storage time should not exceed 15 days. The bottom valve of the water flow pool should be opened every 3-4 days to thoroughly drain the sewage.

Additional information:

Tilapia has a well-developed stomach that can secrete gastric acid, which can digest some algae that other fish cannot use. Under pond culture conditions, most of the contents of the digestive tract are organic debris and other plant feeds, followed by phytoplankton, zooplankton and a small amount of benthic animals, such as water earthworms and chironomid larvae.

As tilapia grows, its diet changes. In the juvenile stage, it mainly feeds on zooplankton, and as the fish grows, it gradually switches to plant feed.

Reference source: Baidu Encyclopedia-Tilapia

Tilapia is an omnivorous fish that mainly feeds on plants. It does not require high feed quality and has a strong digestive ability. It can digest and absorb algae that other fish cannot use, such as Microcystis and Anabaena. A small amount of concentrated feed combined with a large amount of roughage can meet its needs. In addition, it can also eat the residual feed debris on the bottom of the pond and in the water to keep the water fresh.

The reservoir tilapia likes to eat green tilapia the most, but it also eats shrimp, dead fish, small fish, grass, some selenium, some plankton or unicellular algae (their feces are black) because there is no frozen food to eat. The feces of the tilapia in commercial farms are yellow.

Tilapia Farming

Tilapia is a tropical fish with wide adaptability, strong reproductive capacity, omnivorous diet, strong disease resistance, high feed utilization rate, fast growth and delicious meat. It has become a widely cultivated freshwater fish. In particular, the onee tilapia (Oreochromis niloticus♂×Nile tilapia♀) is popular among breeders because of its high male rate, fast group growth and high yield. Maoming City, Guangdong Province, has made full use of the local location advantages and natural conditions to vigorously develop the onee tilapia farming industry and achieved remarkable results. Tilapia farming has a certain scale in Maoming City. In 2003, the area of ​​tilapia monoculture and polyculture reached 380,000 mu, and the output was 130,029 tons, an increase of 44.73% over 89,845 tons in 2001, accounting for 1/3 of the output of the same variety in the province. The output of tilapia farming ranks first among the same varieties in the province. Based on the current pond farming technology, farming experience and reference to relevant onee tilapia technical data, the high-yield pond farming technology and operating procedures for onee tilapia have been formulated.

1 Pond conditions

1.1 Area and water depth The ideal pond area is 5 to 25 mu, with 10 to 15 mu being the best. The water depth of the fingerling pond is 1.0 to 1.8 m, and the water depth of the commercial fish pond is 2.5 to 3.0 m; the height of the pond bank is 35 to 55 cm above the water surface.

1.2 The shape of the fish pond is rectangular and east-west oriented, which is good for ventilation and sunshine. The length-to-width ratio of the fish pond is 1.5-3.0:1.

1.3 The bottom of the pond should be flat and easy to operate with a net. It should be loam or sandy loam. The silt at the bottom of the pond should be controlled within 14 to 20 cm. The pond should have good water retention and no water leakage.

1.4 The water source is mainly surface water. The water source conditions for pond fish farming should consider the following factors:

1) The water quality must meet the requirements of fishery water quality standards GB11607-89;

2) The amount of water must be able to meet the needs of fishery production, especially in the main season of fishery production from May to November, there must be sufficient water entering the pond for pond watering and water replacement. During the production season, the amount of water replacement is generally required to be 10-20% at a time;

3) Each pond has its own relatively independent water inlet and outlet system;

4) The water transparency of the pool is about 30 cm.

1.5 Electricity and fishing machinery are guaranteed. The electricity for commercial fish ponds is required to reach 1kW/mu. When conditions permit, a diesel generator with sufficient power is required as a self-contained power source. Each pond is equipped with 1 to 3 3kW impeller or waterwheel aerators according to the size and stocking volume. Smaller and shallower fish ponds can be equipped with 1 to 3kW water spray aerators. For ponds using hard granular feed, each pond can be equipped with 1 to 2 automatic feeding machines. If gravity irrigation and drainage are not possible, sufficient water injection and drainage equipment should be provided.

2 Preparation before stocking

2.1 Pond cleaning and repair: Repair the pond bank, bottom, water inlet and outlet pump system, etc. to avoid water leakage.

2.2 Remove silt Remove silt once a year to ensure that the silt thickness is controlled within 14 to 20 cm.

2.3 Pond cleaning and disinfection

2.3.1 Dry pond cleaning Dry pond cleaning is to leave only 8-12cm deep water at the bottom of the pond after repairing the fish pond, and use 4-5kg of tea bran or 50-80kg of quicklime per mu to clean the pond and remove toxins. After 3 days of exposure to the sun, the water is returned. The injected water is filtered through a 40-60 mesh screen to remove impurities.

2.3.2 Bleaching powder for pond cleaning contains about 30% effective chlorine. Use 13.5kg of bleach per acre of water with a water depth of 1m, that is, 20g per cubic meter of water, to make the water concentration reach 20ppm, or use 100-150kg of quicklime.

2.4 Apply base fertilizer After the pond returns to water, apply 250 kg of organic livestock and poultry manure per mu to improve water quality. The organic livestock and poultry manure must be fermented and decomposed, and disinfected with 1% to 2% lime. Seeds should be planted 7 days after fertilization.

3. Origin, quality and specification requirements of farmed fish species

3.1 The stocking species must come from a production farm approved by the business department and with an aquatic seed production license.

3.2 Requirements for stocked fish The stocked fish are required to be pure species, uniform in size (within 10% individual weight difference), strong and healthy, and free of injuries and diseases. The all-male tilapia species mainly include the hybrid F1 generation (Oni fish) of pure Aurelia tilapia♂ and pure Nile tilapia♀, Taiwan F1 generation tilapia, and other hybrid F1 generation tilapia with a male rate of more than 92%, a catch rate of more than 85% and fast growth.

4. Fish fry cultivation

4.1 Cultivation Pond The cultivation pond should be 2-3 mu in area, with a water depth of more than 1.5m, sufficient water source, and convenient water inlet and outlet. Before stocking, the pond should be thoroughly cleaned and disinfected, and exposed to the sun for 3-5 days.

4.2 Water quality 7-8 days before stocking, fresh water should be added. The water should be filtered through a 40-60 mesh net to remove impurities. The water depth should be 80cm, and fertilizer (organic fertilizer, chemical fertilizer or green manure, etc.) should be added later. Fish fingerlings should be released after plankton has reproduced in large quantities. After 10 days of stocking, the water depth should be increased to 1.5m.

4.3 Temperature When stocking fry, the temperature difference between the water temperature of the transport fry and the water temperature of the cultivation pond

No more than plus or minus 2 degrees Celsius. The water temperature for cultivation should be kept above 22 degrees Celsius.

4.4 Stocking density: 80,000 to 100,000 fry of the same batch per mu, and release enough at one time.

4.5 Cultivation and Management: The fry are mainly fed with fresh blood pulp of livestock and poultry or cooked soybean powder in the first 3 days after being put into the pond; and are fed with cooked soybean powder, rice bran, yellow powder, low-grade flour and other powders in the next 17 days.

4.6 Fish fry out of the pond for rearing

1) After 20 days of cultivation, the fry generally grow to 3-5cm and can be taken out of the pond and divided into vegetable ponds for fish fingerling cultivation.

2) Remove from the pond and separate. Stop feeding the fish one day before removing from the pond. The nets should be smooth and fine. It is best to open the nets at 9 am on a sunny day. Avoid opening the nets under the scorching sun. The operation should be light and quick, and the fish should be separated and transferred to the pond immediately without lifting water.

5 Fish breeding

5.1 Before stocking, the culture pond and the fry pond should be cleaned and disinfected. Use a 40-60 mesh screen to filter the water and remove impurities. Apply 250kg of pig manure or other livestock and poultry manure per mu. The organic livestock and poultry manure should be fermented and decomposed, and disinfected with 1%-2% lime. The water should be fresh and transparent, about 25cm, and the fry should be stocked after 7 days. The culture water depth should be more than 1.5m.

5.2 Stocking density: 8,000 to 15,000 fry of the same size of 3cm or 5cm should be stocked per mu.

5.3 Feeding After stocking, feed the fish with granular feed containing 32% crude protein and a particle size of 1.5-2mm. Feed twice a day, at 8-9 am and 5-6 pm, and the daily feeding amount is 7-8% of the fish body weight.

5.4 After 20 days of cultivation, the fish grow into mature species, generally reaching a total length of 10-11 cm and a body weight of about 25-50 grams, and can be cultured in separate ponds.

5.5 Disinfection of fish fry and fingerlings The drugs and methods for fish disinfection are mainly the following:

1) Salt: concentration 2%~4%, soak for 5~10 minutes.

2) Bleach: concentration 10ppm~20ppm, soak for about 10 minutes.

3) Penicillin: 80,000 units/50L, soak in water for 5 to 10 minutes.

5.6 Stop feeding the day before leaving the pond. Use smooth and fine 12-mesh seine nets and cages for trapping and sorting. Open the nets and sort at 9 a.m. on a sunny day. Avoid operating under the scorching sun. Use bamboo sieves for sorting, and stock the fish in different sizes.

6. Fish farming in ponds

6.1 Apply base fertilizer After the pond is filled with water, apply 250 kg of organic livestock and poultry manure per mu to improve water quality. The organic livestock and poultry manure must be fermented and decomposed, and disinfected with 1% to 2% lime, and then sow seeds after 7 days.

6.2 Stocking density: High density breeding is adopted. 800 to 1500 tilapia fingerlings are prepared for stocking at one time. At the same time, 35 silver carps with tails of 4 to 5 inches, 40 bighead carps, and 15 snakeheads with tail weight of 15 grams are stocked per mu.

6.3 Feeding and management

6.3.1 Feed with complete hard pellet feed, the protein content of which shall not be less than 28%. Processing quality standards of hard pellet feed:

1) The powder content of hard pellet feed is less than 3%.

2) The diameter of hard pellet feed particles is 20% of the effective diameter of the fish body, and the ratio of diameter to length is 1:1.5~2.0.

3) The feed must be non-deteriorating, have good physical properties and stable nutritional content.

4) The uniformity of feed processing and the particle size of feed raw materials meet the quality requirements of aquatic feed processing.

5) Hard pellet feed has good stability and palatability. Tilapia prefers soft feed.

6.3.2 Feeding amount should be based on weather, water temperature, dissolved oxygen and water quality. Feed twice a day, at 8-9 am and 5-6 pm, feed pellet feed, artificial feeding should be done at set points in the pond, daily feeding amount is calculated as the stock of the day × daily growth rate (reference value 1.2%) × feed coefficient (take the empirical value of 1.7), the next day's feeding amount is calculated as the feeding amount of the previous day × 1.012, and so on.

6.3.3 Feeding method Feeding by feeding machine can save 6-8% of feed compared with manual feeding, and the fish feed evenly and the fish are of uniform size. Therefore, it is recommended to promote the use of feeding machine to feed hard pellet feed. Each pond should be equipped with at least one feeding machine.

6.4 Water quality management Water quality management is one of the key technologies for achieving high yield and implementing healthy aquaculture in ponds. The main regulatory measures are as follows:

1) Keep the water fresh, fresh and tender. Regulate the water quality by fertilizing, controlling water discharge and injection, using quicklime and other measures to keep the water transparency between 25 and 35 cm.

2) The pH value is maintained at 7-8.0. Quicklime, organic fertilizer, chlorine preparations, etc. can be used to regulate water quality. Quicklime is used to control the pH value of the pond water, which is very effective for the acidic nature of most ponds in Maoming City. Sprinkle quicklime solution once per acre per month, generally 7.5-15kg per acre per meter.

3) The dissolved oxygen is above 3mg/L for 24 hours and not less than 5mg/L for 16 hours. The main technical measures are: fertilizing the water quality, controlling the appropriate fertility of the pool water, using biological oxygenation; frequently injecting new water to replenish the dissolved oxygen in the pool water; preventing the water quality from being too fertile, removing silt, etc., so as to reduce the consumption of dissolved oxygen by oxygen-consuming factors.

4) Aerator equipment: equipped with impeller aerator at the standard of 0.3kW per mu. Generally, it is turned on twice a day, from 12:00 to 2:00 noon and from 2:00 to 4:00 in the morning.

5) Prevent the occurrence of "old water" and "water transfer". The following measures are mainly adopted: First, add new water in time or use an aerator to increase oxygen to prevent water quality deterioration; second, sprinkle quicklime, the amount used per mu is 25kg, make pulp and pour wine, and add new water to the original water level; old water can be adjusted by using copper sulfate to treat it for 2 to 3 days and then adjusting it with quicklime.

6.5 Cultivation out of the pond

1) When the fish grow to a certain size, they can be taken out of the pond and sold as commercial fish.

2) Stop feeding the day before selling.

3) When catching and selling, only as many fish as are sold should be rounded up to avoid over-catching and damaging the fish.

7 Fish disease prevention and control Tilapia is susceptible to parasitic or bacterial gill rot, ulcers and frostbite in low-temperature pond water. Avoid drastic changes in water temperature and take oral sulfonamides and antibiotics for prevention; high-temperature pond water breeding will cause ascites (abdominal distension) and red fin desquamation. You can use 15ppm quicklime to spray and take oral antibiotics for prevention and treatment.

Introduction to Tilapia Tilapia, commonly known as African crucian carp, belongs to the order Perciformes, the suborder Perciformes, the family Cichlidae, and the genus Tilapia (also known as the family Cichlidae, the genus Cichlidae). The genus is native to Africa and has more than 600 species, of which 15 are currently farmed. Tilapia is a group of small and medium-sized fish. Its appearance and individual size are somewhat similar to crucian carp, and its fins are more like those of mandarin fish. It is a euryhaline fish that can survive in both sea and fresh water; it tolerates low oxygen and generally lives in the lower layer of water, but changes its water layer with changes in water temperature or fish size. Tilapia has a wide range of diets, most of which are omnivorous and mainly plant-based. They are very greedy and have a large food intake; they grow rapidly, especially in the juvenile stage. The growth of Tilapia is closely related to temperature. The growth temperature is 16-38℃, and the optimum temperature is 22-35℃. Tilapia was first introduced to Taiwan Province from Singapore by Wu Zhenhui and Guo Qichang in 1946. In memory of these two people, it was first called "Tilapia". It was introduced to mainland my country from Vietnam in 1957 and is also known as "Vietnamese fish". Because it is native to Africa and looks like local crucian carp, some people call it "African crucian carp". There are two types of tilapia introduced to Yingshan Hot Spring in Hubei: one is called Mozambique tilapia, which was brought to Yingshan Hot Spring from Jingshan County in 1972; the other is called Nile tilapia, which was introduced by Hubei Fisheries Research Institute in 1979. After they settled down, they all lived well. Indian Dr. Modadugu Vijay Gupta developed and disseminated the cheap technology of clear water aquaculture (using tilapia) and won the 2005 World Food Prize. [Edit this section] Characteristics of tilapia Tilapia has the characteristics of omnivorous diet, tolerance to low oxygen, intolerant to low and high temperatures, and strong reproduction: 1. Omnivorous diet: Tilapia is an omnivorous fish that mainly feeds on plants. The digestive tract contents of tilapia in the pond are mostly organic debris and other plant feeds (such as aquatic plants, commercial feeds, etc.), followed by phytoplankton, zooplankton and a small amount of benthic animals. 2. Tolerance to low oxygen: Tilapia has a strong tolerance to low oxygen, and its suffocation point is 0.07-0.23 mg/L. When the dissolved oxygen in the water is 1.6 mg/L, tilapia can still live and reproduce. When the dissolved oxygen in the water is above 3 mg/L, its growth is not affected. 3. Intolerant to low and high temperatures: The survival temperature range of tilapia is 15-35℃. When the water temperature is below 15℃, tilapia is in a dormant state. The highest critical temperature of tilapia is about 40℃-41℃, the most suitable growth temperature is 28℃-32℃, and the breeding temperature of tilapia is above 20℃. 4. Strong reproduction: Tilapia matures early, has a short spawning cycle, and incubates young fish in the mouth. The breeding conditions are not high, and it reproduces naturally in large areas of static water.

Tilapia is native to Africa. It looks like local crucian carp, so some people call it "African crucian carp". Currently, the main species farmed in my country are Nile tilapia, Mozambique tilapia, and Aurelia tilapia.

Tilapia has the following characteristics: it has a omnivorous diet, is resistant to low oxygen, is not resistant to low or high temperatures, and has strong reproductive capacity:

1. Omnivorous diet: Tilapia is an omnivorous fish that mainly feeds on plants. The digestive tract contents of tilapia in ponds are mostly organic debris and other plant feeds (such as aquatic plants, commercial feeds, etc.), followed by phytoplankton, zooplankton and a small amount of benthic animals.

2. Tolerance to hypoxia: Tilapia has a strong tolerance to hypoxia, with a suffocation point of 0.07-0.23 mg/L. When the dissolved oxygen in the water is 1.6 mg/L, tilapia can still survive and reproduce. When the dissolved oxygen in the water is above 3 mg/L, its growth is not affected.

3. Intolerant to low and high temperatures: The survival temperature range of tilapia is 15-35℃. When the water temperature is below 15℃, tilapia is in a dormant state. The highest critical temperature of tilapia is about 40℃-41℃, the most suitable growth temperature is 28℃-32℃, and the breeding temperature of tilapia is above 20℃.

4. Strong reproduction: Tilapia matures early, has a short spawning cycle, and incubates young fish in the mouth. It does not require high reproduction conditions and reproduces naturally in large areas of static water. Tilapia reaches sexual maturity at 6 months. A female fish weighing about 200 grams carries about 1,000-1,500 eggs. During the breeding period, the male fish has beautiful nuptial colors, and has two openings on its abdomen, the anus and the urogenital opening. White semen flows out when the abdomen is squeezed. The female fish has three holes on its abdomen, namely the anus, the genital opening, and the urinary opening. The water temperature is 18℃-32℃. Mature male fish have the ability to "dig a nest". Mature female fish enter the nest to mate, produce mature eggs and immediately hold them in their mouths, so that

The eggs are fertilized and develop in the female fish's mouth. When the water temperature is 25℃-30℃, the young fish can hatch in 4-5 days. The young fish leave the mother's body when the yolk sac disappears and has a certain ability.

Feeding method:

1. Clean the fish pond. 7-10 days before stocking the fish, drain the pond water, clean it carefully, and disinfect it with quicklime. The amount of quicklime is 150 catties per mu. Block the inlet and outlet with iron gauze or mesh.

2. Stocking of fish. When the water temperature rises to above 18°C ​​after March, stocking begins. For ponds that mainly stock tilapia, stock 2,000 to 3,000 2-3 inch fish per mu; for ponds that stock silver carp, bighead carp, and grass carp, stock 1,000 to 1,500 aoki fish of the same size per mu.

3. Feeding. The crude protein content of the feed should be over 25%. Tilapia compound feed, wheat bran or oil cake can be fed once in the morning and afternoon every day. The feeding amount is 7% of the fish body weight before the fish grows to half a catty; after half a catty, change to 5%.

4. Harvest. The fish can be harvested after 100-120 days of feeding, and more than 70% of the fish can reach more than 1 catty. The commercial fish yield per mu should not be less than 800-1000 catties.