17 



mercuric chloride (Dieter 1974). At 12 weeks, 

 increases in each of the activities of five 

 plasma enzymes (creatine kinase, aspartate 

 aminotransferase, cholinesterase, fructose-di- 

 phosphate aldolase, and lactate dehydroge- 

 nase) of birds were proportional to the log 

 dose of the respective agents. In addition, the 

 pattern of enzyme responses in the experi- 

 mental groups had changed, and was illustra- 

 tive of the specific type of substance that had 

 been fed. The data suggest that qualitative 

 and quantitative identification of environ- 

 mental contaminants in birds, and perhaps a 

 variety of wild animals, may be possible by 

 utilization of multiple plasma enzyme assays. 

 Residue analyses after 12 weeks of feeding 

 showed that DDE accumulated in carcasses 

 and livers at concentrations up to fourfold 

 higher than those in the diets. In contrast, 

 residues of Aroclor 1254 attained in carcasses 

 were identical to, and in livers one-half of, the 

 concentration in the feed. 



Wild-trapped starlings (Sturnus vulgaris) 

 were fed concentrations of DDE or Aroclor 

 1254 (5, 25, and 100 ppm, dry weight) that 

 were found to be sublethal when fed to pen- 

 reared coturnix quail for 12 weeks (Dieter 

 1975). Although the experimental design had 

 been to compare plasma enzyme responses at 

 3, 7, and 12 weeks, reliable measurements 

 could only be made through 7 weeks of the ex- 

 periment because of unexpected mortality. 

 Variations in enzyme response were greater in 

 wild than in pen-reared birds, but not enough 

 to mask the toxicant-induced changes in en- 

 zyme activity. Cholinesterase, lactate dehy- 

 drogenase, creatine kinase, and aspartate 

 aminotransferase activities increased in those 

 fed the organochlorine compounds. Evalua- 

 tion of enzymatic profiles appears to be a po- 

 tentially valuable technique to monitor the 

 presence of toxicants in wild populations, es- 

 pecially if used to complement standard 

 chemical residue analyses. After feeding for 

 7 weeks, liver residues of either organo- 

 chlorine compound were about threefold 

 higher than the concentrations fed daily. 

 However, 4 times as much DDE as Aroclor 

 1254 had accumulated in the carcasses. 



Dietary DDE at levels from 10 to 

 1,000 ppm (dry weight) inhibited nasal gland 

 secretion in mallards maintained in fresh 

 water (Friend et al. 1973). However, in subse- 

 quent studies on the effects of dietary DDE 



(10-250 ppm, dry weight) on osmoregulation 

 and nasal gland function in mallards, Pekin 

 ducks, black guillemots (Cepphus grylle), and 

 common puffins, DDE had minimal effects on 

 plasma electrolyte levels and total nasal gland 

 Na.K-ATPase activities in each of these 

 species (Miller et al. 1976). Liver DDE levels 

 in experimental ducks and guillemots were 

 comparable with those reported for seabirds 

 found dead after kills; levels in starved puffins 

 were much higher. Therefore, DDE at envi- 

 ronmental levels may not affect osmoregula- 

 tion of nasal gland Na.K-ATPase in ducks or 

 in these two species of marine birds. 



Coturnix quail were fed 1 ppm (dry weight) 

 dieldrin, 2 ppm DDE, or the two chemicals to- 

 gether (Ludke 1974). When fed alone, both 

 dieldrin and DDE reached their highest con- 

 centrations in the birds' livers after 28 days 

 on treatment, followed by a slight decrease 

 after 56 days. In whole-body samples (carcass 

 minus liver), dieldrin residues increased stead- 

 ily throughout the treatment period. Dieldrin 

 residues in the birds exposed to dieldrin alone 

 were always similar to residues in birds that 

 were exposed to dieldrin in combination with 

 DDE. In birds fed DDE, either alone or in 

 combination with dieldrin, DDE residues in 

 the carcass increased similarly for 28 days. 

 After 56 days, DDE residues were signifi- 

 cantly greater in the birds fed the dieldrin and 

 DDE mixture. The continued increase of DDE 

 residues when both DDE and dieldrin were 

 fed suggests an interaction in which dieldrin 

 promotes an increased uptake or retention of 

 DDE. 



No weight loss or mortality occurred among 

 bobwhite (Colinus virginianus) fed a control 

 diet or those fed chlordane (10 ppm, dry 

 weight) alone. However, birds that were 

 fed endrin (10 ppm, dry weight) or a combina- 

 tion of chlordane and endrin lost weight and 

 died within a few days (Ludke 1976). Mori- 

 bund individuals had lost considerable body 

 weight and contained much less body fat than 

 did individuals that were not exhibiting signs 

 of intoxication when sacrificed. Birds that 

 died from intoxication averaged weight losses 

 of 32.2% (endrin-treated) and 31.4% (chlor- 

 dane + endrin-treated) when compared with 

 the control group. Individuals that survived 

 exposure had significantly lower brain resi- 

 dues than those that died. Residues of endrin 

 were significantly lower (by 38%) in brains of 



