Linked Life Data

15589250

Source:http://linkedlifedata.com/resource/pubmed/id/15589250

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-3
pubmed:dateCreated
2004-12-13
pubmed:abstractText
The concentrations of 15 metals were measured in the osteoderms (dermal bones) of 30 freshwater crocodiles (Crocodylus johnstoni) from a single population in the Lynd River, northeastern Australia (17 degrees 50'S, 144 degrees 20'E), that were well characterised with respect to site fidelity, reproductive status and age. Multiple linear regression analyses were used to determine the effects of crocodile size (snout-vent length, 25-128 cm), age (0.7-62.7 years), gender (male or female) and reproductive status (sexually mature or immature) on osteoderm metal concentrations. Gender and reproductive status were not significant (P > 0.05) co-predictors of the osteoderm concentration of any metal. In contrast, size, age and osteoderm calcium concentration were highly significant (P < 0.001) systematic predictors of the osteoderm concentrations of all metals, except Na and K. Osteoderm metal concentrations were inversely related (P < 0.001) to both size (r(2) = 0.52-0.92) and age (r(2) = 0.52-0.84), but positively related (P < 0.001) to osteoderm calcium concentration (r(2) = 0.67-0.92). Relative to calcium concentration, the rates of metal accumulation in the osteoderms of C. johnstoni were inversely related to the solubility constant (log K(sp)) of the metal as a phosphate; however this relationship was not linear. This finding is consistent with that previously established for the flesh of freshwater bivalves, which like the crocodilian osteoderm, have a calcium phosphate repository in the form of extracellular granules. The constancy of this relationship between rate of metal accumulation and relative solubility for calcium phosphate deposits, despite contrasting Ca accumulation regimes and taxonomic dissimilarity, points to a potential underlying principle that warrants investigation in a greater range of biota. The implications for using the osteoderms of C. johnstoni as an indicator of metal levels in freshwater ecosystems are also discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0048-9697
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
336
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
71-80
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Patterns of metal accumulation in osteoderms of the Australian freshwater crocodile, Crocodylus johnstoni.
pubmed:affiliation
Environment Division, Australian Nuclear Science and Technology Organisation, Private Mail Bag 1, Menai, NSW 2234, Australia. R.Jeffree@iaea.org
pubmed:publicationType
Journal Article