Control of carapace canker (Brown spot) of cultured Shrimp
The main results are as follows: (1) the bacteria that can be isolated from the focus are Vibrio, Pseudomonas and Flavohacterium. It is a gram-negative bacilli.
(2) there are dark brown or black spotted ulcers on the body surface carapace and appendages of shrimp with symptomatic ① disease, forming brown depressions. The middle part of the depression is deeper, and the periphery of the depression is shallow and slightly white. In patients with severe ②, the ulcer reaches the soft tissue under the carapace, and some diseased shrimps even frontal sword (the forehead xiphoid process of shrimp, also known as shrimp gun), appendages and tail fan are broken, and the cross section is black. Melanin is deposited around the ulcer of shrimp to inhibit the rapid expansion of the ulcer and form black spots. Pathogenic bacteria can invade shrimp from the wound, causing shrimp infection and death.
(3) the diagnosis can be diagnosed with the naked eye, but it should be distinguished from Fusarium disease. Fusarium disease is mainly manifested in the Gill area of cephalothoracic nail, while the location of carapace canker is scattered, such as dorsal nail, lateral nail, tail fan, antennal scales and forehead sword. Secondly, the mycelium and conidia of Fusarium oxysporum disease were observed under microscope, while brown spot disease was mostly motor bacilli.
(4) the epidemic situation is that the disease is caused by the reproduction of a large number of vibrio caused by poor water quality and sediment. In particular, shrimp injury is the most susceptible to infection, which is one of the common diseases of shrimp.
(5) Prevention and treatment of ① by feeding high quality feed. ② ensures that the water environment is good and the water quality is not polluted. ③ regularly sprinkles disinfectants and water quality improvers to maintain a stable environment.
- Prev
Control measures of White spot Syndrome of cultured Penaeus vannamei
1. Main symptoms. Diseased shrimp anorexia, reduced or stopped feeding, diseased shrimp empty stomach, slow movement, weak bouncing, lying still or abnormal swimming; in the later stage of the disease, white spots appeared in the subcutaneous carapace and appendages of shrimp, and carapace softening was also common, and the head and chest nail was easy to peel.
- Next
Breeding techniques of cultured sea cucumbers
Collection and storage of parent ginseng, artificial spawning, fertilized egg hatching and larval breeding management (control of reasonable cultivation density, water exchange and water quality management, suitable bait and feeding, manufacture and release of attachments) juvenile ginseng cultivation. Bait
Related
- A course of planting techniques and methods on how to grow carrots
- How to plant the latest tulips?
- Is it better to pick tea in the morning or in the afternoon? When is the best time for tea to be picked? what is the third or fifth tea?
- Launch Yuanxiao Happy combination Haocha + Tea Yuan healthy Taste
- Penghu Tourism "Fireworks 20 Parade with You"
- 2022 West Lake Happiness holds "Digital Revitalization Voucher" and draws iphone13 and laptop.
- Banqiao Fuzhou social houses are designed to change start-up combined with police elimination to create a safe and livable environment
- The convenient measure of "mechanical weeding" in Xinbei has been abused and the Agriculture Bureau has imposed heavy penalties on the illegal land consolidation.
- Changgeng University Joins Hands with Four Memory Factories to Rescue Memory Talent Shortage
- The list of Taiwan's top 100 MVP managers is listed by the Director-General of the Farmers' Association of Sanxia District.