Retinomotor response in the larvae of brown-marbled grouper, Epinephelus fuscoguttatus
This study examined the retinomotor responses of 14 28, and 42 d old brown-marbled grouper Epinephelus fuscoguttatus under seven orders of magnitude of light intensities from 0 lx to 100 lx to determine the visual thresholds. The retinomotor response was absent in 14 d old larvae, indicating the a...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Academic Journals
2012
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/27387/ http://irep.iium.edu.my/27387/ http://irep.iium.edu.my/27387/ http://irep.iium.edu.my/27387/1/2012_JFAS.htm |
| Summary: | This study examined the retinomotor responses of 14 28, and 42 d old brown-marbled grouper Epinephelus fuscoguttatus under seven orders of magnitude of light intensities from 0 lx to 100 lx to determine the visual thresholds.
The retinomotor response was absent in 14 d old larvae, indicating the absence of the rod visual cells and a reliance on pure-cone retina for vision. The 27–28 d old larvae had rod cells in the retinae and showed weak retinomotor response—the retinal pigment layer was slightly thinner at light intensity <1 lx than at 10–100 lx. The retinae of 42–45 d old grouper showed a clear retinomotor response at 0.1 lx, becoming stronger at 1 lx and higher; 0.1 - 1 lx may be considered the threshold of visual sensitivity of E. fuscoguttatus.
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