35 results about "Oreochromis" patented technology

The invention discloses a preparation method of feed capable of protecting the liver of GIFT oreochromis niloticus and boosting the immunity of the GIFT oreochromis niloticus and a feeding method of the feed. The preparation method comprises the steps of feed preparation and chitosan addition. The feeding method of feed comprises the step of feed feeding. After the GIFT oreochromis niloticus is fed for 9 weeks by adopting the feeding method, the immunity index of the GIFT oreochromis niloticus is obviously increased, the liver stress is decreased, the oxidative stress resistance capacity of the liver is enhanced, the activity of superoxide dismutase, catalase, glutathione and glutathion peroxidase in the liver is obviously improved, and the level of the malonaldehyde is lowered; the level of glucose, cholesterol and low-density cholesterol in serum is obviously lowered; the level of alkaline phosphatase and high-density cholesterol is obviously increased. The chitosan added to the feed is metabolites generated by fermentation of microorganisms without antagonism and is small in molecular weight, easy to absorb, low in cost and relatively easily available. After the feed is taken by the GIFT oreochromis niloticus, the feed is easy to digest and absorb by the GIFT oreochromis niloticus, and residues are barely remained in bodies; the feed has a very good immunopotentiator effect and meets the requirements on novel green healthy additives.

The invention relates to a real-time fluorescence PCR (polymerase chain reaction) method for identifying the gender of oreochromis niloticus, and belongs to the technical field of molecular biology. The research comprises selecting gender-related gene AMH of oreochromis niloticus to design a pair of specific real-time fluorescence PCR primers, wherein the expression quantities of the gene in male fish and female fish have significant difference, the gender of the oreochromis niloticus can be identified by comparing the expression quantity of gene AMH with the expression quantity of adult fish ovary AMH gene. The method provided by the invention is strong in specificity, high in reliability and can be used for identifying the gender of tilapia mossambica at fingerling stage.

Vibrio vulnificus can cause infections in aquaculture-raised fish and is considered an opportunistic human pathogen. We isolated V. vulnificus from diseased hybrid tilapia (Oreochromis niloticus X O. aureus) cultured in a North American water reuse aquaculture facility. We have characterized the isolate using biochemical and molecular methods, developed a disease infection model, and determined that formalin-inactivated whole-cell vaccine provides protection against V. vulnificus. The V. vulnificus isolate was determined to be biotype 1, 16S rRNA type B, vcg type C, and vvhA type 2. Fish vaccinated with the formalin-inactivated whole-cell vaccine responded to vaccination as measured by agglutinating antibody titer. In two separate trials, vaccinated tilapia exhibited relative percent survival of 73 and 60% following challenge with the homologous isolate. In additional trials, vaccinated tilapia exhibited survival values of up to 87.5% following challenge with a heterologous isolate. Use of a mineral oil adjuvant enhanced protection.

The present invention relates to antimicrobial peptides, isolated and purified from extracts of tilapia (Oreochromis niloticus) gills. Such peptides may be produced by chemical synthesis or by expression in heterologous systems, such as bacteria and yeasts, by conventional molecular biology techniques. These peptides show antimicrobial activity against various organisms, including Gram positive bacteria, Gram negative bacteria, fungi and viruses. The invention also includes compositions for controlling pathogens comprising these antimicrobial peptides. The use of such peptides in vaccine preparations, as molecular adjuvants, is also part of the invention.

The invention discloses a method for prompting balanced growth and immune fortification of oreochromis niloticus fries. The method comprises following steps of seedling culture, basic diary food preparation, composite traditional Chinese medicine preparations and seedlings feeding. Compared with the prior art, the method for prompting balanced growth and immune fortification of oreochromis niloticus fries has following advantages: (1) the method is capable of effectively prompting balanced growth of oreochromis niloticus fries so that uniformization of fries; (2) basic diary food in the method is prepared through proper proteins, fat ratio and traditional Chinese medicine ratio such that immunity stress response capabilities of oreochromis niloticus fries are improved; (3) basic diary food and traditional Chinese medicine belong to green feeds and satisfy the safety standard and cause no pollution on fish and water so that the healthy breeding requirement is satisfied.

The invention discloses a method for improving the streptococcus iniae infection-resisting capacity of GIFT oreochromis niloticus during high-temperature stress. The method comprises the following steps: preparing basic ration and a compound Chinese medicinal herb formula, and feeding feed. Due to the adoption of the method, the immunity index of the GIFT oreochromis niloticus during high-temperature stress can be effectively increased, the liver damage is reduced, meanwhile, the streptococcus iniae infection-resisting capacity of the GIFT oreochromis niloticus can be improved, the morbidity is reduced, and the survival rate of the GIFT oreochromis niloticus infected with streptococcus iniae can be increased. Several Chinese medicinal herbs involved in the method are relatively available and relatively low in cost; a production technology is simple. The basic ration with the compound Chinese medicinal herbs has relatively good palatability, and after the basic ration is taken by the GIFT oreochromis niloticus, drug residues in bodies of the GIFT oreochromis niloticus are relatively few, and therefore, the GIFT oreochromis niloticus meets the requirements on green healthy aquatic products.

The invention discloses a method for increasing the survival rate of adults of live oreochromis niloticus. The hormone level, the alexin level and the hepatic antioxidant adaptive capacity can be improved within a short time by increasing breeding density and performing tensioning net stress, and nonspecific immunity is improved. The contents of protein, glucose and triglyceride in blood of the oreochromis niloticus can be increased by feeding feedstuff with high protein level of 36%-39% before the oreochromis niloticus is conveyed, and energy reserve is improved. Moreover, 0.5%-0.8% of compound heartleaf houttuynia herb is added in the feedstuff and contains herba houttuyniae, scutellaria baicalensis, radix isatidis, fructus forsythiae, honeysuckle and the like, and the anti-stress capability of the oreochromis niloticus can be improved. In a conveying process, the water temperature is controlled in a range of 19-23 DEG C, the salinity of water is 8%o-12%o, and dissolved oxygen is sufficient. The metabolic activity of the oreochromis niloticus is low, but the immunity of the oreochromis niloticus is high, so that energy loss in the conveying process is reduced, excretion of metabolin is reduced, and the anti-stress capability is improved. After the oreochromis niloticus is treated by using the method, the survival rate of the adults of the live oreochromis niloticus and the live oreochromis niloticus conveying distance are obviously improved during conveyance.