Effects of exposure of higher doses of cypermethrin in layers hens

Abstract

Cypermethrin (CY), a type II pyrethroid has become a major class of insecticides used to control of ectoparasites that infecting caged layer hens. Although many studies have been done on toxicity of CY on mammals and fishes, little has been evaluated on chicks, especially hens. Thus, this study was carried out on forty-five, 70 weeks old laying hens to evaluate the safety of cypermethrin emulsifiable concentrate 15% (CY-EC) and cypermethrin dust (CY-D). Birds received CY-EC or CY-D applied as a spray and dust, respectively, at the rate of 3-fold higher doses than recommended by the manufacturer and hematological and serum biochemical parameters were evaluated. Results obtained to hematological and biochemical findings showed that CY-EC significantly (p<0.05) increased the levels of hemoglobin, MCV and MCHC while WBC reduced in the treated birds. Similarly, significantly increase in MCHC values was marked in CY-D treated birds; additionally, WBC and basophils values became significantly reduced (p<0.05). There were no statistical differences in the serum chemistry values between layer hens groups before or after CY-EC treatment. However, layer hens CY-D-treated presented decrease of total protein and GGT when compared with the control while glucose showed significantly high values. It can be concluded that CY-EC and CY-D affecting some hematological and biochemical parameters when applied on 3-fold higher doses than recommended by the manufacturer. © Asian Network for Scientific Information, 2013.