Influence of laying on lead accumulation in bone of mallard ducks

Abstract

Paired mallard ducks (Anas platyrhynchos) were given No. 4 lead shot, and bone lead concentrations were compared in drakes and in laying and nonlaying hens. Lead accumulation was significantly greater in bones with a high medullary content (femur and sternum) compared with bones with a lower medullary content (ulna-radius or wingbones). In dosed groups, hens always contained higher bone lead residues than drakes. After dosage with one shot (approximately 200 mg lead), lead in femurs of laying hens averaged 488.4 ppm compared with 113.6 ppm in nonlaying hens. Femurs of drakes averaged 9.4 ppm lead. Dosage with the second lead shot did not result in further accumulation of bone lead in hens, but increased bone lead concentrations threefold in drakes, suggesting that saturation levels for bone lead had already been reached in the hens after ingestion of one shot. There was no demonstrable relationship between egg production and bone lead residues. The high lead residues, found in medullary bones of laying hens indicate that sex and physiological condition are major factors influencing lead absorption by bone.

Prevalence of lead exposure among age and sex cohorts of Canada geese

“…Howdosing individuals with various amounts of lead shot (Jordan ever, many exist, On the and and Bellrose 195 ;Bellrose 1959;Longcore et al 1974; time of year. No data on the association of age and sex with ~i~~~~ et al 1976 ; Finley et 1976a; Dieter and Finley lead exposure in Canada geese (Branta canadensis) or other 1978; Finley and Dieter 1978;Trost 1981), assaying wing 'pecies Of geese are bones for lead concentrations (Anderson 1975;White and much is known about the of shot ingesstendell 1977; Stendell et al 1979), and examining gizzard tion and the occurrence of lead poisoning in waterfowl, little contents for ingested shot in hunter-killed ducks (Elder 1950; is about background lead levels Or how prevalence Of lead exposure varies among age and sex classes in a discrete during an annual cycle. We examined the preva- , and wintering grounds (Swan Lake National Wildlife Refuge (NWR)) of the Eastern Prairie Population of Canada geese.…”

Tissue levels of lead in experimentally exposed herring gull (Larus argentatus) chicks

“…In dosed birds, lead accumulated at high levels in feathers, reaching a level exceeding 900 n£ J. BURGER AND M. COCHFELD Longcore et al (1974) suggested that short-term high exposure and a long-term low-level exposure might have the same consequences with respect to the ultimate level of lead in the bone. Female mallards dosed by Finley and Dieter (1978) showed a dramatic increase in bone level with a single lead pellet dose compared with controls, but birds receiving two pellets had no higher levels than those exposed to one. Their accumulation curves match type C (female) and type B (males; Fig.…”

“…White and Stendell (1977) found a high correlation between number of shot in gizzard and bone lead levels. Finley and Dieter (1978) point out that there are higher concentrations in bones with higher medullary content, femur and tibia have higher levels than the radio-ulna, and a low-calcium diet increases deposition of lead in bone. Pattee (1984) found no difference among the tibia and humérus of control kestrels, but a 2x increase in the tibias at a 10 ppm diet of lead, and a 4.7 x difference at 50 ppm.…”

Calcium availability influences lead accumulation in a passerine bird

“…This would enhance the intestinal absorption of toxic metals. In ring doves (Streptopelia risoria; Kendall and Scanlon, 1981) and mallards (Anas platyrhynchos; Finley and Dieter, 1978), egg laying females revealed a greater uptake of lead in bone tissue than males (reviewed in Scheuhammer, 1987). This suggests differences between sexes in lead accumulation related to differences in calcium metabolism.…”