Fish Diseases and Management

2.2.6 Wound ulcers

An ulcer may be caused as a result of traumatic injury, microbial or parasitic lesions.  After the formation of ulcer, affected area becomes susceptible to infection by opportunistic pathogens such as Myxobacteria and Saprolegnia spp. Ulcer development causes damage to the semi permeable membrane separating the environment and milieu interior leading to the failure of osmotic regulation.

Wound healing

In fishes wound healing is temperature dependent. At higher temperature the wound healing is faster and it is completely retarded at lower temperature. Wound healing in fish is faster than that of terrestrial animals due to the direct contact with water and the animal body.

Malphigian cells help in wound healing. The malphigian cells migrate from the surrounding tissues  and form a single layer of epidermis over wound  to enclose it, following which slower and temperature dependent reconstruction of the epithelial cover can be achieved by normal mitotic proliferation. Wound healing may lead to formation of scars at the wounded area. Contamination of ulcerated surface by bacteria prevents the migration of peripheral epithelial cells thereby inhibiting the process of wound healing.