Milk shrimp disease is a serious problem for aquaculture operations around the world. It’s caused by a bacteria called Vibrio alginolyticus, which affects the shell and outer tissues of crustaceans such as shrimp and crab. The symptoms of this disease include white lesions on the body, their shell discoloring and softening, appetite loss, lethargy, and ultimately, death.
There are several potential causes of milk shrimp disease. Poor water quality is one of the main ones, particularly high levels of ammonia or nitrate in the water. Other possible causes include overcrowding, poor nutrition, stress due to shipping or handling, and inadequate sanitation. In some cases, even specific temperature changes can cause this disease to occur.
The most effective way to prevent the spread of milk shrimp disease is to maintain good water quality and proper nutrition in aquaculture tanks. Regular water testing should be done, and any changes in water chemistry should be addressed quickly.
Symptoms of Milk Shrimp Disease
The most common symptom of milk shrimp disease is white lesions or spots on the body, shell, and appendages. These lesions will usually appear as white flecks or patches that can turn into larger areas of discoloration. The affected shrimp can also have signs of lethargy and appetite loss.
In more severe cases, the shell will become soft and easily breakable. If left untreated, the infection can quickly spread throughout the tank and lead to death of most or all of the shrimp.
Diagnosing Milk Shrimp Disease
Milk shrimp disease is typically diagnosed by visual inspection of the shrimp. If white lesions or patches are present, a sample should be taken for laboratory analysis to confirm the presence of Vibrio alginolyticus. In some cases, further testing will be necessary to determine the exact cause of the infection.
Stages of Milk Shrimp Disease
Milk shrimp disease progresses in three stages.
The first stage is the initial infection, which occurs when Vibrio alginolyticus enters the body of a shrimp or crab. During this stage, white lesions and discoloration usually appear on the shell and other tissues, but the infected crustacean will still be active and eat normally.
The second stage begins once the infection has spread throughout the body and begins to affect other organs. At this point, the shrimp will begin to have signs of lethargy, appetite loss, and discoloration.
The third stage occurs when the infection has become so severe that it causes death. This stage is usually identifiable by their shell softening and breaking, as well as complete mobility loss and appetite loss.
Treating Milk Shrimp Disease
The most effective treatment for milk shrimp disease is to improve water quality and nutrition in the tank. Regularly cleaning the tank and changing out water can help prevent the spread of infection. If the infection has already progressed, antibacterial medications will be necessary to treat existing lesions and reduce symptoms.
Preventing Milk Shrimp Disease
The best way to prevent milk shrimp disease is to maintain a healthy and clean environment for the shrimp. Proper water quality and nutrition should be closely monitored, and any changes in water chemistry should be addressed quickly. Regularly cleaning the tank and changing out water is also important in order to reduce the buildup of bacteria that can lead to infection. Stocking the tank with a diverse range of shrimp species can also help prevent disease, as many types of illnesses are species-specific.