Lead Toxicity in Mute Swans

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stress. The concentration of protoporphyrin IX is elevated and is 1
indicative of lead poisoning, following disruption of haeme synthesis
(Lee, 1981).
Glucose levels were variable in the lead poisoned birds,
but if the high levels of lead in the pancreas caused this elevation,
it is not known.
Since no reference values were available for Whooper swans, the
reference levels for Mute swans (Tables 1-2) were used to detect
changes in blood chemistry examined.
However, only with further study
of blood chemistry for Whooper swans will it be possible to detect
accurately biochemical changes due to lead poisoning.
From the reference distributions established in this study, changes
occurring in the blood of Mute swans following lead ingestion can be
detected.
While values for acutely lead poisoned birds are
informative, small changes can be detected in chronically poisoned
birds, using reference values reported here.
Caution in the
interpretation of levels of haemoglobin and protoporphyrin should,
however, be exercised.
Further study is required to determine
sub-lethal effects of lead in Mute swans.
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