Cypermethrin-induced Repeated-dose Immuno-toxicity in Oryctolagus Cuniculus: An Investigation into Pathology of Spleen and Blood

Background: Cypermethrin is a pyrethroid insecticide widely used in agriculture and medicines. Its toxicity effects on spleen and blood in male and female rabbits is studied in this research. Methods: Age- and weight-matched does/females (n=24) and bucks/males (n=24) of Japanese White rabbits were subjected to intraperitoneal cypermethrin administration @50, 100 and 150 mg.kg-1 b.wt. in groups B, C and D, respectively.  The experimental rabbit does and bucks were tested for hematology alterations after each of 5 CY-treatments, at days 1, 8, 15, 22 and 29.  One rabbit doe and one rabbit buck were sacrificed fortnightly (days 15, 29, 43, 57 and 71) to obtain spleen for histological studies. Results: CY-treated rabbit bucks developed anemia, leukopenia, neutropenia, monocytosis, eosinophilia and basocytopenia mostly in dose and time dependent manner.  In contrast, rabbit does show transient but significant leukocytosis, neutropenia, lymphopenia, monocytosis, eosinophilia and basophilia only in high dose group.  Moreover, spleen histology revealed congestion, depletion of white pulp with increased red pulp and hemosiderin deposition in CY treated rabbit bucks, but not rabbit does. Conclusions: This study concludes that immuno-toxicity by cypermethrin insecticide is not similar in male and female subjects.