The effects of constant light and constant darkness on daily changes in the morphology of the pineal organ in the goldfish,Carassius auratus

1982 ◽  
Vol 53 (4) ◽  
pp. 277-292 ◽  
Author(s):  
J. A. McNulty
Keyword(s):  
Carassius Auratus ◽  
Pineal Organ ◽  
Constant Light ◽  
Constant Darkness ◽  
Goldfish Carassius Auratus ◽  
Daily Changes

Effects of pinealectomy and bilateral enucleation on the phototactic response and on the conditioned response to light of the goldfish Carassius auratus L.

1970 ◽  
Vol 48 (1) ◽  
pp. 175-182 ◽  
Author(s):  
James C. Fenwick
Keyword(s):  
Conditioned Stimulus ◽  
Carassius Auratus ◽  
Conditioned Response ◽  
Pineal Organ ◽  
Swimming Activity ◽  
Conditioning Situation ◽  
Goldfish Carassius Auratus ◽  
Light Gradient ◽  
Phototactic Response

Intact goldfish in a light gradient were unevenly distributed and spent most of their time in the darker half of the gradient. Pinealectomized, bilaterally enucleated, or pinealectomized plus bilaterally enucleated goldfish were distributed uniformly throughout the light gradient. It was concluded that the phototactic response of goldfish depends upon the presence of the pineal organ as well as the eyes.In a conditioning situation, pinealectomized animals with intact vision showed significantly more responses to the conditioned stimulus than did the control animals with intact vision when the conditioned stimulus was light, but not when the conditioned stimulus was sound. Blind goldfish, with or without an intact pineal, could not be effectively conditioned to light although they did become conditioned to sound. Pinealectomy did not affect the conditioning of either the blind or the eyed goldfish to sound.Among goldfish with intact vision, pinealectomy increased the spontaneous swimming activity. Blinding enhanced the level of spontaneous swimming activity more than did pinealectomy. But blind plus pinealectomized goldfish displayed a level of spontaneous swimming activity which was intermediate between the level shown by pinealectomized eyed animals and blind animals with an intact pineal.The significance of these findings has been discussed in terms of the photosensory role of the goldfish pineal organ.

SEM of Hepatocytes and Biliary Passages in Goldfish Liver

1977 ◽  
Vol 35 ◽  
pp. 556-557
Author(s):  
Waykin Nopanitaya ◽  
Joe W. Grisham ◽  
Johnny L. Carson
Keyword(s):  
Carassius Auratus ◽  
Cell Layer ◽  
Three Dimensional ◽  
Cell Types ◽  
Biliary System ◽  
Fish Food ◽  
Commercial Fish ◽  
Goldfish Carassius Auratus ◽  
Commercial Fish Food

An interesting feature of the goldfish liver is the morphology of the hepatic plate, which is always formed by a two-cell layer of hepatocytes. Hepatic plates of the goldfish liver contain an infrequently seen second type of cell, in the centers of plates between two hepatocytes. A TEH study by Yamamoto (1) demonstrated ultrastructural differences between hepatocytes and centrally located cells in hepatic plates; the latter were classified as ductule cells of the biliary system. None of the previous studies clearly showed a three-dimensional organization of the two cell types described. In the present investigation we utilize SEM to elucidate the arrangement of hepatocytes and bile ductular cells in intralobular plates of goldfish liver.Livers from young goldfish (Carassius auratus), about 6-10 cm, fed commercial fish food were used for this study. Hepatic samples were fixed in 4% buffered paraformaldehyde, cut into pieces, fractured, osmicated, CPD, mounted Au-Pd coated, and viewed by SEM at 17-20 kV. Our observations were confined to the ultrastructure of biliary passages within intralobular plates, ductule cells, and hepatocytes.

Induction of Gynogenesis and Androgenesis in Goldfish Carassius auratus (var. oranda)

2001 ◽  
Vol 36 (3-4) ◽  
pp. 195-198 ◽  
Author(s):  
I Paschos ◽  
L Natsis ◽  
C Nathanailides ◽  
I Kagalou ◽  
E Kolettas
Keyword(s):  
Carassius Auratus ◽  
Goldfish Carassius Auratus
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