BHC not found to reduce the shell quality of hens' eggs.

Abstract

SEVERAL organochloride pesticides are said to have detrimental effects on the eggshell quality of a variety of avian species. The eggshell thickness of ducks is reduced by feeding dieldrin and DDE1,2; that of American kestrels by DDE3; of Japanese quail by DDT4 and of American sparrow hawks by a mixture of DDT and dieldrin5. Indeed, a mathematical relationship seems to exist between DDE residues and shell thinning6. Major structural defects, apart from shell thinning, have also been found to occur in the eggshells of quail fed DDT or chlordecone7. Now that the use of DDT has been, or is about to be, banned in many parts of the world, γ-BHC (lindane) is becoming the most widely used pesticide in this class. However, little is known about its effects on birds. Whitehead et al.8 found that feeding γ-BHC at moderate levels (about 100 mg/kg diet) to hens permanently reduced their egg production by 25%, although no detrimental effect was observed on shell thickness. In contrast, Sauter and Steele9 have claimed that feeding it to hens at a lower level, 10 mg/kg diet, slightly reduced shell thickness.