Further Evidence for a Three-Year Oocyte Maturation Time in the Winter Flounder (Pseudopleuronectes americanus)

1970 ◽  
Vol 27 (5) ◽  
pp. 957-960 ◽  
Author(s):  
R. S. Dunn
Keyword(s):  
Oocyte Maturation ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Maturation Time ◽  
Size Groups

Evidence is presented for autumn growth of yolkless oocytes, which would tend to split the oocytes into two size groups.

Oocyte Maturation and Ovulation Induced in Hypophysectomized Winter Flounder (Pseudopleuronectes americanus) by Preparations from Pituitary Glands of American Plaice (Hippoglossoides platessoides)

1977 ◽  
Vol 34 (11) ◽  
pp. 2142-2150 ◽  
Author(s):  
C. M. Campbell ◽  
D. R. Idler
Keyword(s):  
Key Words ◽  
Oocyte Maturation ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Con A ◽  
Pituitary Glands ◽  
Hippoglossoides Platessoides

Hypophysectomized winter flounder (Pseudopleuronectes americanus) did not undergo spontaneous oocyte maturation, but the glycoprotein fraction of extracts of American plaice (Hippoglossoides platessoides) pituitaries induced maturation and ovulation. The nonglycoprotein fractions, previously shown to contain a vitellogenic factor, were less efficient than the glycoprotein fractions in the induction of maturation and ovulation. The activity of the nonglycoprotein fraction was further reduced by rechromatography on Con-A Sepharose, suggesting that its action on oocyte maturation and ovulation was due to contamination by the glycoprotein gonadotropin. Key words: hypophysectomy, gonadotropin, oocyte, maturation, ovulation, vitellogenesis, flounder, plaice, Pseudopleuronectes, Hippoglossoides

Aspects of the Anatomy of the Winter Flounder Ovary with Hypotheses on Oocyte Maturation Time

1969 ◽  
Vol 26 (7) ◽  
pp. 1943-1947 ◽  
Author(s):  
R. S. Dunn ◽  
A. V. Tyler
Keyword(s):  
Oocyte Maturation ◽  
Winter Flounder ◽  
Maturation Time

Ovarian tissues of mature winter flounders have distinct groups of oocyte types which suggests that a minimum of 2 or 3 years pass from the time that oocytes become histologically recognizable until they are spawned.

The Winter Flounder (Pseudopleuronectes americanus) in Long Pond, Conception Bay, Newfoundland

1971 ◽  
Vol 28 (8) ◽  
pp. 1153-1165 ◽  
Author(s):  
V. S. Kennedy ◽  
D. H. Steele
Keyword(s):  
Food Intake ◽  
Growth Rates ◽  
Plant Material ◽  
Early Growth ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Food Items ◽  
Fish Remains ◽  
Males And Females ◽  
Conception Bay

Monthly samples of winter flounder taken in Long Pond from November 1962 to October 1963 indicated that the flounder moved into deeper water (7–10 m) during the summer and returned to shallow water (1–2 m) from September to June. These movements corresponded to the end of the spawning season and the ripening of the gonads respectively. Spawning occurred from March until early June, most of it in May and early June. Most males were mature at age 6 and most females at age 7. Fifty percent of the males and females were mature at 21 and 25 cm respectively. The growth rates of the males and females were similar until the age of 8, after which the females apparently outgrew the males. Early growth and fecundity were similar to those reported for other areas. No feeding took place in December or January but the flounder fed in March and continued to feed throughout the summer; food intake decreased in the fall. They were omnivorous and the type of food eaten varied with the locality. Polychaetes, plant material, and molluscs were the most common food items throughout the year. Capelin eggs and fish remains were found only during a few months of the year but were eaten in great quantities.

Sign in / Sign up

Export Citation Format

Share Document