REPRODUCCION Y CONTROL

That most crustaceans have to cope with both somatic growth and ovariangrowth in adult life is often overlooked. There is little uniformity in the

strategy of programming of these two high- energy consuming processeswithin the Crustacea, and indeed more patterns may exist than we havedescribed. Groups using the same strategy may show some uniformity in

their relative dependence on specific hormones controlling growth andreproduction. Thus, in crustaceans in which somatic growth and ovariangrowth are scheduled as antagonistic events, somatic-growth-promotinghormones may either restrain in release of reproductive hormone(s) or

restrict gonadal responsiveness to reproductive hormone(s) and vice versa. In crustaceans in which somatic growth and ovarian growth are

synergistically programmed, reproductive hormone(s) are not likely to evokea somatic-growth restraining influence. Another aspect that must be

critically examined in future studies is the precise role of eyestalkhormone(s) (GIH?) on ovarian growth. Are GIH and MIH the same

hormone? Is GIH inhibitory or restrainatory?

Vitellogenin (Vg) synthesis in cultured tissues was analyzedbiochemically in Kuruma prawn, Penaeus japonicus . Ovary

and hepatopancreas dissected from early vitellogenic femaleswere incubated in vitro in lobster Ringer containing

super(14)C-amino acids. The synthesis of total protein and Vgwas assayed by the radioactivity incorporated into precipitates

with trichloroacetic acid and anti-vitellin (Vn)-serum, respectively. The ovary and hepatopancreas incorporatedradioactivity into the protein synthesized in vitro. Protein

synthesized by the ovary and precipitated with anti-Vn-serumwas shown by electrophoresis and fluorography to consist of

two radioactive polypeptides corresponding to the componentsof Vg. The protein synthesized by the hepatopancreas in vitro

did not show any precipitin line against anti-Vn-serum. Theresults indicate that the ovary is the site of Vg synthesis in

kuruma prawn

Changes in weight and water content of the hepatopancreas and ovary of Crangoncrangon are described in relation to body weight and ovarian development. Percentage of water content of the organs in relation to ovarian stage was

determined for 43 females; organ wet weight data were obtained from another 137 animals. All stages of gonadal development (oogenesis, previtellogenesis, vitellogenesis, and depleted) were represented in the sample population of

ovigerous, nonovigerous, and postovigerous females. The ovary andhepatopancreas progress through cycles of progressive and retrogressive changes

in weight and volume which are characterized by a phase shift between the twoorgans. This resembles a Volterra-Lotka system, for which equations were derived. Wet weight of the ovary increases by 69% through previtellogenesis, and by 282% from pre- to secondary vitellogenesis. This represents an increase of 5.5% of body

weight occupied by the ovary during development. The hepatopancreas nearlydoubles in size from early oogonial development through previtellogenesis, butdecreases markedly during vitellogenesis. The net result is an increase from a

minimum value of 4% to a combined organ volume occupying 9.5% of total bodyweight when the ovary is full vitellogenic. Increase in ovarian mass during

development is not due to water increase. Water content decreases from > 70% in immature ovaries to 46% in vitellogenic organs. The hepatopancreas also loses

water, but to a lesser extent: from 73% in oogenic individuals to 67% in vitellogenicanima

Haefner,P.A.J.; Spaargaren,D.H.1993. Interactions of ovary and hepatopancreasduring the reproductive cycle of Crangon crangon (L.). 1. Weight and volumerelationships.J.CRUST.BIOL. 13(3):523-531

Final oocyte maturation, spawning, mating, and their interrelationships, differsignificantly between open-thelycum and closed-thelycum species of penaeidshrimp. In open-thelycum species, mating occurs some 2 h before final oocytematuration and spawning, following vitellogenesis, but precedes vitellogenesis

in closed-thelycum species. Final maturation and spawning of commerciallyreared penaeid shrimp are often induced by factors such as temperature

shock, filtration of seawater or darkness. In addition to these factors, matingbehaviour and spermatophore transfer directly trigger final maturation and

spawning in species with an open thelycum. Final maturation and spawningare also induced by seawater irradiated with ultraviolet light in Penaeus

japonicus and by diets containing EPA (a precursor of prostaglandin) andvitamin E in P. monodon. These findings suggest that final maturation andspawning may be induced by prostaglandin(s), that originate from EPA and

whose secretion is stimulated by water borne products of UV irradiation

CRUSTACEOS CON COMPORTAMIENTO DE APAREAMIENTO COMPLEJO