Should the aerator be opened after bacillus subtilis is used on aquaculture

2022-04-24 0 By

Chinese surface water has been found to contain 68 antibiotics, with aquaculture one of the main sources of contamination, according to a recent study.While strictly restricting the use of antibiotics in aquaculture, we should increase the research on antibiotic substitutes in aquaculture.Bacillus subtilis is widely used in aquaculture as a microecological agent which can replace antibiotics and has good antibacterial and stability.Bacillus belongs to gram-positive bacteria, aerobic, can produce spores, is a kind of heterotrophic bacteria with high activity digestive enzyme system, high temperature resistance, stress resistance.Bacillus can reduce the content of nitrate and nitrite in water, so as to improve water quality.It can also compete with harmful algae and various pathogenic bacteria in the breeding environment to form dominant populations, so as to have a certain inhibitory effect.Bacillus species, currently available are: bacillus subtilis, coagulated bacillus, bacillus, bacillus licheniformis, slow short wax bacillus, bacillus, annular bacillus, big strong bacillus, bacillus, Oriental, bean sprouts spore bacillus coli, bacillus lactobacillus, butyric acid, spindle, etc.1. Characteristics of Bacillus subtilis and its mechanism of Action Bacillus subtilis is a short rod-shaped, non-pod movement gram-positive bacteria, strictly aerobic, is China’s Ministry of Agriculture officially approved the use of probiotics, with the following characteristics:1) Acid resistance, salt resistance, high temperature resistance (100 ℃) and extrusion resistance, can be affected by pellet feed processing, especially aquatic pellet material processing, which is the condition that many other microorganisms do not have.2) In the storage process in the form of spores, in the dormant stage, does not consume feed nutrients, does not affect the quality of feed.In the upper segment of the intestinal tract, the rapid resurrection, transformation into a metabolic role of nutritional cells.3) The reactivated spores can produce a large number of protease, amylase, phytase and hemicellulose hydrolase to supplement the deficiency of intestinal enzymes in cultured animals and improve the utilization rate of feed, thus promoting the growth of animals.4) In the process of growth and reproduction, it can produce more than 18 kinds of AN acid, vitamin B, VC and VK and other effective active ingredients to maintain animal health and provide nutritional needs.5) A large amount of aerobic, the formation of intestinal anaerobic environment, conducive to the proliferation of lactic acid bacteria and other beneficial bacteria, improve the role of intestinal biological barrier, resist the colonization and invasion of pathogenic bacteria.6) Can produce vibrio and yeast active substances, fish hydrophila, hemorrhagic septicemia pathogen, large yellow croak pathogen, Chinese mitten crab pathogen and staphylococcus aureus have a strong inhibitory effect.7) It can decompose carbon, nitrogen, phosphorus and sulfur pollutants, decompose complex polysaccharides, proteins and water-soluble organic matter, and improve water quality.To sum up: fast propagation: fast metabolism, fast propagation, four hours of multiplication 100,000 times, standard bacteria four hours can only multiply 6 times;Strong vitality: no humidity can withstand low temperature -60℃, high temperature +280℃, strong acid, strong alkali, antibacterial disinfection, high oxygen (oxygen reproduction), low oxygen (anaerobic reproduction);Large volume: the volume is four times larger than the general pathogenic bacteria molecules, occupying space advantage, inhibiting the growth and reproduction of harmful bacteria.2. Application of Bacillus subtilis in fish culture Adding Bacillus subtilis in feed can promote the growth of fish, adding beneficial source bacillus subtilis in feed can significantly increase the weight gain rate and survival rate, reduce the feed coefficient, and reduce the contents of AN nitrogen, nitrite and COD have significant effects.Feeding bacillus subtilis can improve the digestive enzyme activity of fish.Bacillus subtilis can produce a variety of enzymes, improve the host digestive enzyme activity, intestinal nutrient digestion and absorption, feed utilization has a direct impact.Adding bacillus subtilis into fish bait can inhibit pathogenic bacteria, stimulate immune system and improve immunity.3. Application of Bacillus subtilis in shrimp Culture Bacillus subtilis had obvious inhibition effect on Vibrio harveyi, which reduced the cumulative fatality rate of black tiger shrimp by 90%.Significantly reduce mortality rates.4. Application of Bacillus subtilis in improving water quality Long-term cultivation will accumulate a large number of residual bait, excreted waste, animal and plant residues and harmful gases (AN, hydrogen sulfide, etc.) at the bottom of the aquaculture water, which often lead to water quality deterioration and poisoning of aquatic animals.It is found that the metabolism of some beneficial microorganisms in aquaculture water has oxidation, hydrogenation, nitrification, denitrification, phosphorus solubilization, sulfurization and nitrogen fixation, and can decompose the above organic substances into carbon dioxide, nitrate and liusuan salt.In this way, it can not only remove harmful substances and purify water in time and effectively without interrupting the breeding process, but also provide nutrients for the propagation of single-celled algae and promote the propagation of algae.The photosynthesis of these algae provides oxygen for the breathing of animals and the decomposition of organic matter in the pond, thus forming a benign ecological cycle, which is beneficial to the growth of aquaculture animals.At the same time, due to the large number of beneficial microorganisms, the dominant population is formed in the pool, which can inhibit the propagation of pathogenic microorganisms and reduce the occurrence of diseases.Bacillus subtilis can consume a large amount of organic matter in water, decompose it into small molecular organic acids, AN-based acids and AN, improve water quality, provide nutrients for monoplasms, and purify water quality.After bacillus subtilis preparation was used in water, the dissolved oxygen and pH of cultured water were not significantly affected, but the an nitrogen, nitrite and sulfide were significantly decreased.It was found that bacillus subtilis was added to the crab pond and fish pond respectively as a water quality improtant. It had significant degradation effect on an nitrogen, nitrite nitrogen and sulfide in the pond. The maximum degradation peak appeared in 3-4 days, and the effective time lasted more than 7 days.The results also showed that Bacillus subtilis could significantly purify water quality and reduce COD, nitrite nitrogen and AN nitrogen in shrimp pond.The results showed that only when the concentration of bacillus subtilis was over 1 000mg/kg, the fish could die of hypoxia due to the oxygen consumption of bacillus subtilis and the oxidation of culture medium in water.Therefore, as a water conditioner according to the water quality every 7 d sprinkling the whole pool 1 times, after use, open oxygen generator in time to ensure the best use effect.5. The use of Bacillus subtilis is recommended in the morning or noon of sunny days, the best to have wind and waves at the same time!Remember: rainy days, hot weather when the solution can not use spore!This kind of weather pond mouth itself is easy to hypoxia, combined with the use of bacillus will accelerate the occurrence of hypoxia!Bacillus subtilis in aquaculture has two directions: one is water purification, bacillus subtilis can consume organic matter in water, it is decomposed into small molecular organic acid, an acid and an, improve water quality, to provide nutrition for single cell algae, can decompose organic matter, comprehensive purifying water environment, improve the bad water quality.The other is taken internally, that is, added to feed to aquatic animals for food.Bacillus subtilis added to the feed for fish feeding, can improve the gastrointestinal function of fish, improve the profit rate of feed, improve meat quality, promote longevity, disease prevention effect is very good, mainly by the occupying effect of Bacillus, and is able to produce beneficial metabolites.Fish can increase about 10%, generally a week can see the effect, the proportion of adding should not be too much,300-500g/t or so, the highest should not exceed 0.1-0.2%.Mix bacillus subtilis and feed evenly and evenly.Bacillus subtilis purification of water quality, high density breeding, per mu of one meter deep water pond, according to 200-400 grams to add, according to the water quality and the depth of how much to use, can be more or less, the best in the morning 9-11 or so when the sun began to use, water temperature is more than 25 degrees appropriate, water temperature is too low, the effect is not good.It is recommended that the water temperature not lower than 15 degrees.Bacillus subtilis is an oxygen consuming bacterium, which needs to increase oxygen when used. If there is no oxygen increasing equipment for freshwater cultivation, the amount of adding can be reduced, which can be about 100g/ mu.Need to be activated before use, specific is: beneficial source bacillus subtilis 1 bag +2 kg brown sugar +20 kg water sealed fermentation for 3-7 days, pond bottom silt more pond can be added to use.Once again, oxygen must be added when used, otherwise aquatic animals may die because of hypoxia. Generally, about 7-10 can be used once.High density farming can be increased use.Under what circumstance should use spore fungus, how to distinguish good from bad?Here is a reference scheme: wash a white plastic bucket, and then fill a bucket of water in the middle of your pond mouth, and then let it stand for half an hour. If there is obvious precipitation at the bottom of the white plastic bucket after half an hour, it means that your pond mouth can use Bacillus subtilis!If not, that can be temporarily used!The same method also can differentiate the bacillus effect that you buy how!When you use it, after two days on the shore you will obviously see the water becomes clear that is even better!If not sure, also in the same position and then half a bucket of water, let stand for half an hour, if the impurities become less, so that you buy the bacillus effect is ok.Special reminder, bacillus to identify beneficial source bacillus.Note: 1. Bacillus is aerobic bacteria, should be used in the morning of sunny days, there is oxygen equipment, open oxygen machine when sprinkling, increase dissolved oxygen, make it in water reproduction quickly form a population advantage.2. Bacillus preparations are mostly powdery products, existing in the form of dormant spores. Before use, they must be activated and multiplied by oxygen fermentation for 6-8 hours to improve the use efficiency of bacillus.