Prevention and Treatment Protocol for Bacterial Edema in River Crabs

2026-06-05

Location: Shiqiao Town, Dangtu County, Ma’anshan, Anhui Province

Date: June 2nd

Water quality parameters: pH 8.4, ammonia nitrogen 0, nitrite 0

As air temperatures rise, rainfall becomes more frequent, weather conditions are highly variable, and stress levels increase; meanwhile, pond water is turbid, temperatures remain low, stocking densities are high, and dissolved oxygen at the pond bottom is insufficient, leading to excessive internal energy consumption and a higher incidence of edema disease in Chinese mitten crabs.

Clinical signs: The junction between the abdomen and the ventral carapace of affected crabs becomes swollen, resembling the condition of a river crab about to molt. Gentle pressure on the carapace elicits a small amount of fluid extrusion. Affected crabs exhibit sluggish movement, refuse to feed, and ultimately die from asphyxiation due to respiratory distress in shallow water. Edema is often accompanied by bacterial infection–related symptoms such as a mottled liver, black gills, enteritis, and shell ulcers.

The proposed solution is:

1. External disinfection and bottom treatment: Zhongren Jindian, 3 mu per bottle; Super Strong Bottom Cleaner, 3 mu per packet.

2. Oral administration: Mix one packet each of enrofloxacin powder, Gantai Liver & Gallbladder Formula, and Life‑Essence with 40 jin of feed, and administer for 5–7 days.