and larval viability in sea bream culture is still low, as a consequence
of mortalities and a high incidence of skeletal deformities (dystrophies).
Dystrophies are not always immediately apparent, leading to wasteful
use of food, energy, space and human resources. Abnormal cartilage
growth and calcification are key features of skeletal deformities.
Parathyroid hormone-related protein (PTHrP), recently identified
as a hypercalcaemic hormone in fish, appears to mediate ossification.
Calcium is also essential in many other physiological processes,
such as reproduction and growth.
i) establish the relative contribution of the diet and the environment
to calcium balance;
ii) determine the art played by PTHrP in larval development, growth
iii) identify the genes involved in bone development and their
regulation by PTHrP; and
iv) generate guidelines for the use of calcium in sea bream husbandry.
first objective is to identify the relative importance of the
different sources of calcium during critical phases of development,
growth and reproduction in a normal production cycle on a fish
farm. The second objective is to determine experimentally whole
animal calcium omeostasis during larval developement, vitellogenesis
and normal growth, and the role of PTHrP in maintaining homeostasis.
These will be related to observations of calcium requirements
and balance made on the fish farm. The third objective will be
to determine the molecular mechanisms which underpin bone formation
in fish and the way in which PTHrP regulates this process. The
PTHrP gene promoter(s) will be identified and used to characterise
factors which may influence its expression in vivo. Genes differentially
expressed during endochondral bone formation, and thus strong
candidate genes for this process, will be isolated and their regulation
determined by PTHrP.
UNIVERSIDADE DO ALGARVE
VIVEIRO VILANOVA, S.A.
Vilanova de Milfontes
Tel.: +351 283997048
Fax: +351 283997047
MEDICAL RESEARCH COUNCIL
Tel.: +44 1223248011
Fax: +44 1223402180
THE VICTORIA UNIVERSITY OF MANCHESTER
Tel.: +44 1612757114
Fax: +44 1612752445
KATHOLIEKE UNIVERSITEIT NIJMEGEN
Tel.: +31 243653300
Fax: +31 243652126