What if the crab has rust spots?

There are rust spots on the body surface of river crabs, brown and reddish brown spots on breastplate, toenail and footsteps, even scorched, and sometimes white spots. These spots further develop into black ulcers, and in severe cases, the carapace is eroded into holes, which leads to bacterial and fungal infection, which seriously affects the feeding of river crabs and leads to the death of river crabs.

The occurrence of this disease is mainly caused by the deterioration of pond water quality, excessive heavy metal ions, or by some Vibrio which can decompose chitin of river crab chitin from the wound.

Prevention and control of rust spots on crabs

1. To provide a good growing environment for river crabs, clear the pond thoroughly, remove the sludge, clean the pond with quicklime and apply quicklime every 15 to 20 days to keep the water fresh.

2. Care should be taken in the process of transportation, fishing and breeding to prevent river crabs from being injured.

3. To treat diseased crabs, the average water depth was 1 meter per mu, and the whole pond was sprinkled with 0.5 kilograms of bleach powder. At the same time, the river crabs were given norfloxacin powder, 0.2 grams per kilogram of feed for 3 consecutive days.