Histopathology of gill tissue koi carp (Cyprinus carpio) infected Myxobolus sp. with treatment of diflubenzuron

Along with the development of aquaculture activities, certainly, there are many problems that can interfere with the cultivation process one of the causes is because of parasite attacks on fish. One of the parasites that often attacks koi fish is Myxobolus sp. The purpose of this study was to determine the histological picture and the effect of giving Diflubenzuron on the damage to the gill tissue of koi fish (Cyprinus carpio) with the treatment of Diflubenzuron. The method used in this study is an experimental method using 5 treatments namely (A) healthy fish, (B) fish infected with Myxobolus sp., (C) fish infected with Myxobolus sp. and Diflubenzuron dose 0.01 mg, (D) of fish infected with Myxobolus sp. and Diflubenzuron dose 0.02 mg and (E) fish infected with Myxobolus sp. and Diflubenzuron dose 0.03 mg. Histopathological observations were made on gill tissue. The level of gill tissue damage can be determined by the scoring method. Based on the results of the study, there were three tissue damages found in histopathological observations of gill tissue, namely oedema, hyperplasia, and lamella fusion. Treatment of Diflubenzuron with different doses has a different effect on the level of gill tissue damage. The conclusion of this study, the treatment of Diflubenzuron 0.02 mg (D) has the best effect compared to other doses, evidenced by the reduction in damage to the gill tissue.