Histopathological study of the influence of Aloe vera extract on wound healing in common carp (Cyprinus carpio)

Although the Aloe vera plant is well known for its anti-inflammatory, anti-viral, anti-bacterial and immunostimulant properties, but it is more known because this herb has a role in wound healing and freshness in human skin. However, Aloe­ vera has not been used for wound healing in aquaculture. This study was carried out to evaluate the healing effect of Aloe vera on the surgical wounds in fish skin. For this purpose, 150 common carps (120-150 g) were divided into following 5 groups. Fish were anesthetized with MS222 (Tricaine methane sulfonate) and then skin wounds with 5mm diameter and full thickness and circular shape were created by surgical punch biopsy on the left side of each fish. In order to study the healing effect of Aloe vera extract following treatments were applied: group 1 received no treatment (control group), group 2 received a permanent floating in 3% Aloe vera extract, group 3 received oral treatment, through diet containing 5% Aloe vera extract, group 4 received a short time bath containing 10% Aloe vera extract (10±1 min) and group 5 received a permanent floating in 0.5 mg/lit malachite green. Tissue samples were taken from the skin wounds at day 7th, 14th and 21st from six fish in each time, fixed in 10% formalin and then processed through routine histological methods.The results showed that epithelialization, regeneration of injured subepidermal compartment, formation of granulation tissue, angiogenesis and formation of scales were better in group 4 than the other groups. In day 21st, formation of normal epidermis, dermis and scale were more completed in group 4 compared to the others. On the basis of these results, it can be concluded that short time bath with Aloe vera has positive effects on the wound healing in fish. However, permanent floating of fish in Aloe vera may alter water quality and food intake and indirectly has negative effects on wound healing. In order to obtain a more solid results further research is recommended.