Document 2w56QbXDv7N4GQp6OoQd8nDR

Df:ect of Aroclor 12 54 on King Doves u.nd Kestrels. David B. Peakall, Jefferey L.Linear (Section of Dcology and System~tics, Cornell University) and Stephen D. Lloom (Department of Poultry Science, Cornell University). The brseding success of Ring Doves(Streptopolla ri__riw) fod Aroclor 1254 at lOppn was determined over two generations. Si.: pairs of birds no re fed PCB's for three months, then allowed to Incubate their clutch of two eggs. Then eggs ..ere collected ag_in until six months when they ,,ere allowed to Incubate another clutch. Results are given In table 1. The lew hatching aucoess of the 2nd generation was due to heavy embryonic mortality. The age of embryonic death varied considerably, mainly in the range of 3*8 day3. This finding Is at variance ,.ith that of Scott et. ul.(1971) *ho found significant deorease in hatohability of chicken eggs In tkj first generation with lOppm ..roclor 1248 for eight weeks -ni almost complete failure at both four and eight weeks at 20ppm ..roclor 1248. In this case mortality ooourred lamodi-tely before h-tohing. Dgsshall thinning was not observed in either the fi.at or second generation(Pee.kull, 1971; and unpublished data}. This Is In agreement with the findings of Dahlgran und.Linderii (1971) for the pheasant(Phaslanu3 oolchloua)and Heath et. :.l. (In press) for ths Mallard[Anas platrhynohoa) and Linear (unpublished)for the American KestreHJtico `aaarvarlua). Some studies were made on the levels ox carbonic anhydraso In the ovlduqt of Kestrels treated with Aroclor 1254(10ppm In diet), DDD(5ppm) ox DDR + Aroclor 1254(5pp and lOpp* respectively). Sample size was small, but values Indicate no ocr.3-30 ..lth Aroclor 1254 -ni decreases with Aroclor 1254 + DDd were equivalent to DDR ..lone. This finding agrees laok If eggshell thinning caused by PCB's. Chromosomal studies, using three day embryoes, havo been started. -/J 4 Vrv* (( HONS 045955 Residue analysis on eggs 1-id at v-rious times from th.; start Of ths experiment showed that the levels increased for three m/ibths when an approximately steady nixXm level of 50 ppm(dry weight) was reached. Tha second generation eggs h_d slmilur levels; thus increased embryonic) mort-lity was not caused by increased levels of PCB's. The most striking finding of the seabird "wrack" in the Irish Sea in 1969 was the elevated concentration of PCB's in the liv9r(Holdgate,1971). In birds shot as contrcls the concentration was only 0.4ppm(wet ..eight) wherea3 birds found dead had 4-Oppm in the liver. In an attempt to ev-lu-.ta these findings we stressed five first generation birds -fter they had been exposed to Aroclor 1254 in their diet for six months. The stress was applied by reduslng the food intake severely so that the birds lost approximately 10 percent body -weight per waek. Control,birds were also stressed in a similar m-nnar. Bo signfloant difference ..as found in either the time to death nor in the wfcight loss to death between controls and experimental groups. The organ IjvjM of the first generation birds saorified at the end of the breeding experiment can be oompared to organ levels after stravation(tabl2). A massive Increase in all tissues studied as a result of mobilization of fat Is clearly shown. The faot that liver levels ranged from 937 # 1688 ppm -t the time of death strongly suggests that the 40ppm recorded in the seabirds In the Irish Sea was not responsible for the de-th of these birds. Table 1. Ho. of pairs Pre-experiment 1st generation 2nd generation Control, 2nd gin. 6 f. 6 6 laid 24 24 20 24 Hatched 22 24 4 22 Fledged 22 24.. 2 22 One pair failed to produce any eggs during the period of the experiment. ** Pledging losses oonsisted of one young found outside the nest at one day of age .-nd one deformed bird killed at the age of three weeks. HONS 045956 Table 2. Musole Brain Liver fat Fre-stress 6.1 * 2.3(4) 14.1 - 9-9) 5.5 - 1.6(4) 15-3 12.6(^736.1 t 211.6 (4.8-8.0) (3.6-27.5) (401.2-1069.4) Poet-stress 172.9 i 38.3fo293.0 i 27.6(91118 i 267(5) (120.0-227.0) (254.0-340.2) (937.3-1688.0) Figures are means, standard deviations, sample size and range. No fat present. -/ . f 0 2 * j. ft* // -it,/- tin* HONS 045957