Elvestad K, Karlog O, Clausen B
Nord Vet Med. 1982 Mar;34(3):92-7.
During the severe winter of 1978-79, large numbers of mute swans died in coastal areas of Denmark. Of these, 2111 were collected for examination. The analyses confirm previous findings of relatively high copper levels in mute swans (mean for 178 livers was 2680 mg/kg dry weight (Dw) and for 110 kidneys 34 mg/kg Dw) (Table I, Fig. 1). The copper content was not related to sex or age (Table II). The highest liver levels of copper were found in swans from Western Jutland. Cadmium was found at the same relatively low levels as recorded for waterfowl elsewhere (mean for 178 livers was 12 mg/kg Dw, for 110 kidneys 24 mg/kg Dw) (Table I, Fig. 2). The cadmium content was not sex-related, but it increased with age (Table II). The mean mercury content (liver) was 1.4 mg/kg Dw in the 10 birds analysed (Table I). The mean lead content was 15 mg/kg Dw in the 178 livers analysed and 31 mg/kg Dw in 110 sternum (Table I and Fig. 3). The lead content was not sex-related. In sternum, but not in livers, it was related to age (Table II). One third of the swans were found lead-contaminated probably after ingestion of lead pellets. None of the swans carried high levels of both copper, cadmium, and lead (Table III).
在1978 - 1979年的严冬期间，丹麦沿海地区有大量疣鼻天鹅死亡。其中，2111只被收集用于检查。分析证实了之前关于疣鼻天鹅体内铜含量相对较高的发现（178份肝脏样本的平均值为2680毫克/千克干重，110份肾脏样本的平均值为34毫克/千克干重）（表一，图1）。铜含量与性别或年龄无关（表二）。日德兰半岛西部的天鹅肝脏中铜含量最高。镉的含量与其他地方水禽的记录水平相同，相对较低（178份肝脏样本的平均值为12毫克/千克干重，110份肾脏样本的平均值为24毫克/千克干重）（表一，图2）。镉含量与性别无关，但随年龄增长而增加（表二）。在所分析的10只鸟中，汞含量（肝脏）平均为1.4毫克/千克干重（表一）。在分析的178份肝脏中，铅含量平均为15毫克/千克干重，在110份胸骨中为31毫克/千克干重（表一和图3）。铅含量与性别无关。在胸骨中，而非肝脏中，铅含量与年龄有关（表二）。三分之一的天鹅可能在摄入铅弹后被铅污染。没有一只天鹅同时含有高水平的铜、镉和铅（表三）。
