

CHRONIC TOXICITY OF SOME NEW INSECTICIDES TO BOB-WHITE QUAIL 
Introduction 
Early pharmacological research on DDT indicated its hich ili 
‘pointed to the possibilities of the compound being Se aaateae nage eae 
body tissues. Subsequent studies have shown that other new insecticides of 
the chlorinated hydrocarbon group possess some of the same characteristics 
(Lehman, 1948). These qualities of resistance to metabolic activity and 
capabilities for storage in tissues increase hazards to vertebrate life 
beyond those that might be evident as acute poisoning effects. 
Numerous field and laboratory studies by the Fish and Wildlife Service 
and others have shown in a general way the immediate hazards to wildlife that 
result from some insecticide applications. These studies have shown that 
control work involves dosages of DDT that are not sufficient for rapid acute 
poisoning of birds and mammals. However, these dosages, because of various 
qualities of the toxicants, and certain features of control activity, may 
impose hazards of chronic poisoning. 
Coburn and Treichler (196) conducted studies with DDT to determine its 
chronic poisoning levels for quail. The comparatively small amount of 0.025 
percent of the compound administered in feed over a period of two months | 
proved critical for 50 percent of the test animals. Over this same period 
some mortality resulted with the minimum amount tested (0.005 percent). At 
0.40 percent, the highest concentration used in feeding tests, an acute 
response was found with a 100 percent kill of 10 test birds in 2) hours. 
In 1947, other evaluations of new insecticides were made to determine 
dosage levels that result in chronic poisoning of quail. In addition to 
DDT, TDE or DDD (dichlorodiphenyldichloroethane), benzene hexachloride and 
toxaphene (chlorinated camphene) were tested. Medication was in feed at 
the level of 0.025 percent of each insecticide, and twenty 12-week-old quail, 
equally divided as to sexes, comprised a test group for each toxicant. In 
preliminary tests extending over lL days, deaths attributed to insecticide 
poisoning were as follows: DDT, 3; TDE, 2; benzene hexachloride, 1; and 
toxaphene, 1. Weight records for birds in these tests failed to show any 
marked differences, although DDT-fed birds not only suffered the greatest 
mortality but also showed the least gain in weight. Additional evaluations 
of new insecticides in 198-9 provide the basis for this report. 
It was previously found that 0.025 percent of toxicant was not suffi- 
ciently high to provide for comparisons among compounds of lower toxicity 
than DDT. Also, medication at this level required dosing over rather ex- 
tended periods before effects were apparent. In order to remedy these 
objections to the earlier routine, the concentration of toxicant in feed 
was increased to higher levels of 0.05 and 0.1 percent. 
