Effect of Chlorpyrifos Insecticide On The Ossification of Wader Pari Fish Vertebrae (Rasbora lateristriata)

Abstract

Due to high growth, chlorpyrifos was one of the solutions to increase food production. However, this compound is dangerous because it belongs to the organophosphate group, which blocks the activity of the acetylcholinesterase (AChE) enzyme and causes nervous failure in an animal. Due to heavy rain, this insecticide will run off and contaminate the river's body and affect aquatic life. Rasbora lateristriata pari was a non-target animal of chlorpyrifos. This study aimed to determine the effect of chlorpyrifos exposure on the behavior of the R. lateristriata's feeding and swimming response, as well as the morphology and ossification process of the vertebrae. The study was conducted for seven days. Four groups of fish were exposed to chlorpyrifos with concentrations of 0, 0.001, 0.005, and 0.01 ppm. Observation of the ossification and morphological process of vertebrae is carried out using AR-Ab bone staining. Observation of R. lateristriata's behaviors is carried out using descriptive analysis. It was found that the fish exposed to chlorpyrifos showed some behavioral abnormalities in swimming and feeding responses. Fish exposed to 0.005 ppm chlorpyrifos showed vertebral abnormalities, which is haemal kyphosis. Kyphosis refers to Λ-shaped vertebral curvature. However, the ossification process represented by Ar-Ab staining is going well. The novelty in this study relates to the research results obtained. This study provides an initial overview of the vertebrae of R. lateristriata exposed to the insecticide chlorpyrifos. The benefits of this findings are to become a source of initial information related to R. lateristriata for future research.