Fish Feed Machine Knowleagde

1. Protein is the main nutritional index of compound feed for fish
The protein content in the feed is one of the criteria for measuring the nutritional level of the feed, but it is not that the higher the protein content, the higher the quality of the feed. Protein is the main nutritional index of fish compound feed. The level of protein directly affects the internal quality of fish feed.

Fish have a low sugar utilization capacity. Protein is the main nutrient for fish growth, and most of it must be obtained from food. Therefore, the protein content of aquatic feed is generally required to be much higher than that of poultry and livestock feed. In order to ensure the healthy growth of fish. In essence, fish and shrimp do not need protein but amino acids. But animals cannot synthesize amino acids from simple inorganic substances, they must directly or indirectly obtain amino acids from ingesting animal and plant foods. Therefore, fish and shrimp compound feed should not only pay attention to the quantity of protein, but also pay attention to its quality.

Excessive protein content will not only cause waste of feed protein resources, but also cause liver and gallbladder disease, fish body obesity, intolerance of stress like human obesity, and increase the pressure on pond water quality management. Too high protein content fish can not metabolize, it will excrete more organic waste into the water body, which not only increases the cost, but also causes damage to the water environment, forming eutrophic fertilizer water.

Too low protein content, on the one hand, will cause slow growth of fish and poor disease resistance, on the other hand, it will delay production opportunities. Too low protein content can not meet the physiological needs of the fish body, malnutrition, poor growth, the feed coefficient will be high, and sometimes it will cause physical weakness and disease.

2. Fish with different diets and different growth stages have different feed protein nutrition.
Different types of fish and different growth stages have different optimal protein requirements. Carnivorous fish need high-protein feeds, while vegetarian fish have lower protein requirements. Appropriate protein content is generally less than 30% for herbivorous fish (such as grass carp), 30-35% for omnivorous fish (such as crucian carp), and 35-40% for carnivorous fish (such as catfish).

Fish in the seedling stage must have a high nutritional requirement for protein in order to meet the urgent physiological needs of new organisms. Large seedlings or finished fish can appropriately reduce the nutritional level. Therefore, mastering the optimal protein level of fish feed is of great benefit to guiding fishery production.

For omnivorous fish such as carp and crucian, the optimum protein content of the feed at the spray fry stage is 40%-45%, and the optimum protein content of the feed at the seedling stage is 35%-40%. The protein content is 30% to 35%.

For herbivorous fish, the optimum protein content of feed at the seedling stage is 30% to 32%, and the optimum protein content of feed at the adult stage is 25% to 28%.

The optimal protein content of catfish feed at the seedling stage is more than 40%, and the optimal protein content of feed at the adult stage is more than 35%.

3. Different water temperature should also appropriately adjust the protein content in the feed.
For example, the protein content should be relatively reduced in the hot season. Just like people, eat lighter in the hot summer to facilitate the digestion and absorption of fish. Otherwise, fatty liver and other phenomena will occur. Similarly, the low temperature season should relatively increase the protein content of the feed, just like people eat some dog meat and mutton in winter, increase the heat accumulation of the fish body to dissolve the erosion of the freezing to the body, so as to ensure the energy required for fish metabolism and growth.

4. Fish feed protein index should be based on animal protein.
According to the source of raw materials, protein can be divided into two categories: animal protein and vegetable protein. Fish meal, meat and bone meal, and blood meal are rich in animal protein. The amino acids contained in these proteins are similar to those required for fish growth. This protein not only has a high absorption rate, but also has the advantages of fast absorption and low water pollution. Therefore, the protein of high-quality aquatic feed should be based on this animal protein. However, cottonseed meal, alfalfa meal, rapeseed meal, etc. mainly contain vegetable protein. Aquatic feed fish produced from this raw material has a low absorption rate, slow absorption, and serious water pollution.

In addition, in essence, the absorption and utilization of protein by fish is the utilization of essential amino acids, because protein is composed of amino acids. Vegetable protein contains fewer essential amino acids for fish, which is the fundamental reason why aquatic feeds tend to emphasize animal protein. As long as this obstacle is overcome, aquafeeds can surpass the dependence on animal protein.