A bacterial agent for preventing and treating white stool syndrome of Litopenaeus vannamei and its preparation method and application

Abstract

The invention relates to a bacterial agent for preventing and treating white stool syndrome of Litopenaeus vannamei and its preparation method and application. The bacterial agent of the invention is a fermented bacterial powder prepared by spray-drying the fermented liquid of Enterococcus faecalis. The preparation method of the bacterial agent for preventing and treating white stool syndrome of Litopenaeus vannamei of the present invention comprises the following steps of successively drying Enterococcus faecalis through shake flask culture, first-level seed culture, second-level seed culture and fermentation culture to obtain the control Inoculum of Litopenaeus vannamei white stool syndrome. The application of the bacterial agent for preventing and treating white stool syndrome of Litopenaeus vannamei according to the present invention is to mix the bacterial agent into the feed according to the ratio, and then use the feed to feed the common bacteria in ponds that produce (treat) or do not produce (prevent) white stool. Lime prawns. The Enterococcus faecalis bacterial agent of the present invention can significantly inhibit the growth and reproduction of pathogenic bacteria such as Vibrio cholerae, Edwardsiella tarda, Aeromonas hydrophila, etc., has broad-spectrum antibacterial properties, can prevent and treat white stool disease of Litopenaeus vannamei, and has a good control effect Reached more than 78%, the effect is remarkable.

Description

technical field [0001] The invention belongs to the technical field of microbial bacterial agent disease prevention, and relates to a bacterial agent for preventing and treating white stool syndrome of Litopenaeus vannamei and its preparation method and application. Background technique [0002] According to the 2017 China Fishery Yearbook data, the output of Litopenaeus vannamei in China reached 932,300 tons in 2016. However, since 2010, the frequent white stool syndrome of prawns has been one of the major problems affecting the sustainable development of the shrimp aquaculture industry. one. The main symptoms of white stool syndrome of Litopenaeus vannamei are: the feces of sick prawns are slender and white (such as cotton thread), sticky, and gather in a large number in the air outlet floating under the water surface, and emit a foul smell. At present, Litopenaeus vannamei is mainly treated with antibiotics such as enrofloxacin, or combined with some traditional Chinese ...

AI Technical Summary

Problems solved by technology

[0005] (2) Cao Haipeng et al. believe that the pathogenesis may be due to the massive growth and proliferation of Vibrio cholerae in the intestinal tissue of Litopenaeus vannamei, adhesion to the intestinal mucosa, and the production of virulence factors on the surface, causing damage to the intestinal wall and mucosa, and further through the hemolymphatic circulation to the The hepatopancreas tissue reproduces and produces toxins in it, leading to hepatopancreas enlargement, erosion and other lesions, which eventually lead to dysfunction of the hepatopancreas and intestines, causing the disease and death of Litopenaeus vannamei

There is no report on the prevention and treatment of white stool syndrome of Litopenaeus vannamei with Enterococcus faecalis