THE INFLUENCE OF STARVATION AND COPPER EXPOSURE ON THE COMPOSITION OFTHE DORSAL CARAPACE AND DISTRIBUTION OF TRACE-METALS IN THE SHORE CRAB CARCINUS-MAENAS (L)
Jj. Scottfordsmand et Mh. Depledge, THE INFLUENCE OF STARVATION AND COPPER EXPOSURE ON THE COMPOSITION OFTHE DORSAL CARAPACE AND DISTRIBUTION OF TRACE-METALS IN THE SHORE CRAB CARCINUS-MAENAS (L), Comparative biochemistry and physiology. C. Comparative pharmacologyand toxicology, 106(2), 1993, pp. 537-543
1. The influence of starvation and copper exposure on the composition
of the carapace of the shore crab, Carcinus maenas has been investigat
ed. The effects of the concentrations of selected trace metals in the
carapace and midgut gland have also been examined. 2. Differences in n
utritional state did not affect the concentrations or relative proport
ions of the principle carapace components (calcium, chitin and protein
), but starvation was associated with a reduction in carapace copper c
oncentration. Copper concentration in the midgut gland increased in ''
starved'' crabs, while midgut gland zinc and calcium concentrations re
mained unchanged. 3. Starvation in combination with copper exposure (0
.5 mg Cu/l) resulted in alterations in both carapace composition and t
race metal loads. Carapace calcium concentrations were reduced signifi
cantly following copper exposure irrespective of the nutritional state
of the crabs. However, the reduction was more marked in ''fed'' crabs
than in ''starved'' animals. 4. Copper-exposed crabs exhibited raised
carapace copper concentrations while carapace zinc concentrations wer
e depressed. Such changes were most pronounced in copper-exposed ''sta
rved'' crabs. 5. Calcium concentrations in the midgut glands of ''star
ved'' copper-exposed animals were significantly elevated compared with
those in either control or ''fed'', copper-exposed crabs. 6. The find
ings are discussed with regard to their ecotoxicological significance.