Biesiot et al.: Ovarian development in Rachycentron canadum 



693 



700 



1 2 3 4 1'/ 



DEVELOPMENTAL STAGE 



S 

 a 



E 



< 



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 O 



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1 2 3 4 V 2' 



DEVELOPMENTAL STAGE 



2 3 4 V 2' 



DEVELOPMENTAL STAGE 



2 3 4 1' 2" 



DEVELOPMENTAL STAGE 



Figure 5 



(A) Mean protein concentration (|ig protein/mg dry weight (DW) ± standard deviation) 

 in developing cobia, Rachycentron canadum, ovaries. (B) Mean lipid concentration (|ig 

 lipid/mg dry weight ± standard deviation). (C) Mean carbohydrate concentration (ug 

 carbohydrate/mg dry weight ± standard deviation); note change in Y-axis scale. (D) Mean 

 ash concentration (|ig ash/mg dry weight ± standard deviation); note change in Y-axis 

 scale. l=stage-l previtellogenesis; 2=stage-2 vitellogenesis; 3=stage-3 final maturation; 

 4=stage-4 postovulation; l'=stage-l' sequential previtellogenesis; 2'=stage-2' sequential 

 vitellogenesis. Numbers above error bars are sample sizes. 



subsequent early larval development before first- 

 feeding. The lipid:protein (L:P) ratio of ripe cobia 

 oocytes (not ovaries as reported in the present study) 

 was 1: 0.7 (Caylor, 1992 ), which is similar to both striped 

 bass, Morone saxatilis, eggs (1: 0.6) (Eldridge et al., 

 1982) and red drum, Sciaenops ocellatus, eggs (1:0.8) 

 (Vetter et al., 1983). Winter flounder, Pseudopleuro- 

 nectes americanus, eggs, however, had a much higher 

 L:P ratio of 1:5.2 (Cetta and Capuzzo, 1982). 



One factor affecting the storage of biochemical com- 

 ponents is egg size. Many marine fish eggs are rela- 

 tively small and do not have large stores of energetic 



reserves; these small eggs usually hatch quickly. Co- 

 bia eggs range from 1.16 to 1.42 mm in diameter (Jo- 

 seph et al., 1964). Red drum eggs are 0.86-0.98 mm 

 (Vetter et al., 1983) and striped bass oocytes are 3.3- 

 3.4 mm after hydration (Eldridge et al., 1981). Win- 

 ter flounder eggs are the smallest, 0.74-0.85 mm di- 

 ameter (Smigielski and Arnold, 1972), yet they are 

 composed of about five times as much protein as lipid. 

 Thus, generalizations about energy reserve storage 

 cannot be made based solely on egg size. 



Winter flounder eggs are demersal whereas eggs 

 of cobia, red drum, and striped bass are pelagic. De- 



