Annual Cycle of Serum Gonadal Steroids and Serum Lipids Associated With Migration of the Striped Mullet, <em>Mugil cephalus</em> L.

The striped mullet, Mugil cephalus, a valuable food resource for man, has been found in estuaries throughout the world. The present study examines changing physiological responses of the reproductive system in conjunction with the fall schooling and migratory periods.Serum gonadal steroids increased 8-10 fold from late September to the end of November for both sexes. The gonadal mass and Gonado-Somatic Index of Mugil cephalus rose rapidly in October and November returning to prespawning values in December. Fluctuations were observed in the serum total lipids, cholesterol, and triglycerides, throughout the study period. A decline in the summer followed by a sharp increase in October and November was observed in the serum total lipids and cholesterol for both sexes. Observed changes in gonadal condition in Autumn occurred simultaneously with the shortening in photoperiod to under 12 hours and a temperature drop approaching 20°C.The dramatic increase in gonadal steroids, gonad mass, and GSI's of Mugil cephalus were indicative of the fall promigratory reproductive development. The observed fluctuations in serum total lipids and cholesterol appeared to be associated with the period of rapid deposition of body lipids and subsequent mobilization for reproductive development and migration. Stimulus for timing the reproductive cycle may be attributed to shortening photoperiod and decreased temperature.

Level thesis:degree_level

Thesis

Year

1979

Author dc:creator

• Dindo, John Joseph

• Mugil cephalus L.
• Physiological responses
• Reproductive system
• Gonadal steroids

Repository record dc:identifier

https://digitalcommons.library.uab.edu/etd-collection/7116

OAI identifier oai:identifier

oai:digitalcommons.library.uab.edu:etd-collection-8108