Evaluation of rodenticidal potential of yellow oleander (Thevetia neriifolia tuss.) seed powder in wild female African giant rat (Cricetomys gambianus W.)

Abstract

Cricetomys gambianus is a wild rodent species attacking crops. Conventional rodent control is via the use of synthetic rodenticides with  health and environmental concerns. Thevetia neriifolia seed reportedly has rodenticidal potential in the laboratory rodents. However,  rodenticidal activity of T. neriifolia seed has not been evaluated in wild rodent species. Therefore, this study attempted to evaluate the  rodenticidal potential of yellow oleander seed powder in wild C. gambianus. Twenty wild-caught female C. gambianus were acclimatized  for 4 weeks in Animal house and randomly allocated into 4 groups including control. The T. neriifolia seed was dried under the shade,  blended, and mixed with a commercial feed with 4 different concentrations of the seed powder (0%, 20%, 40%, and 80%) and then turned  to pellet. The acclimatized animals were fed with appropriate concentrations of the formulated feed for 8 weeks. Body-Weight and Feed- Intake of the animals were taken. Their behavior before and after introduction of the feed was also recorded. At termination, tissue  samples (Kidney, Liver, and Heart) were collected for histopathology analysis. Data were analyzed in SPSS using ANOVA and means  separated using DMRT at α . The results showed no significant effect on the animals' mean Body-Weight and Feed- 0.05 Intake (p˃0.05).  No mortality and behavioral changes were observed in the animals at all the concentrations. No visible lesions in the kidney, liver, and  heart across the treatment groups compared to control. In conclusion, T. neriifolia seed powder did not have rodenticidal effect on the  wild female C. gambianus. Therefore, it could not be used as a rodenticide in the management of wild rodent species population.