Table 1 shows how the features used in our histological analysis are related to the 5 stages of the visual maturity scale used in our macroscopic analysis and that the resting stage
corresponds to skipped spawning.
67%), whereas the animals in the high-salinity treatment were well distributed among the resting stage
(20%), the early growth stage (40%) and the late growth stage (40%).
Moreover, resting stages
also afford species a temporal refugium from adverse conditions (Marcus and Boero 1998).
In these species there are differences in the amount of gonad material found during the resting stage
The gonads degenerated quickly from the middle of August to the middle of September, such that, by the end of September, it was almost impossible to distinguish between the sexes of Atrina pectinata until the end of the resting stage
Oysters from the Carmen, Machona, and Mecoacan lagoons showed a reproductive tactic in which the resting stage
50) Gonad stage Microscopic criteria 1 Immature Oogonia and primary growth oocytes present; high proportion of connective tissue, no atresia or MAs, ovarian membrane thinner than in resting stage
Oysters in the resting stage
were found at the beginning of the experiment in all treatments; in the subsequent harvests, a reduction in the number of animals in the resting stage
was observed (Fig.
During the annual reproductive cycle, the size of the gonad tissue increases to occupy most of the area of the visceral mass, whereas a few small follicles are present during the resting stage
After a short sexual resting stage
(end of August through September), a new cycle began.
During September and December, most clams were sexually in the resting stage
Individuals in the resting stage
were found from December to February (Fig.