The ontogeny of ultraviolet photosensitivity in rainbow trout (Salmo gairdneri).
The present study examines the changes in ultraviolet (UV) photosensitivity that occur during the growth of rainbow trout (Salmo gairdneri). A comparison of the ocular media transmission of small (n = 3) and large (n = 3) trout eyes did not reveal large changes in the transmission of UV radiation through the eye. We used the heart-rate conditioning technique to measure spectral sensitivity in immobilized trout. Four trout, each weighing less than 30 g, exhibited a UV-sensitivity peak at 360 nm while four additional trout weighing more than 60 g each exhibited no evidence of UV sensitivity. Spectral-sensitivity measurements of two trout weighing 44 g and 60 g revealed UV sensitivity, but when measured one month later (after a 25% increase in body weight) both fish exhibited no UV-sensitivity peak. At this time their sensitivity appeared to conform to the known blue-sensitive cone mechanism.
Hawryshyn
C W
CW
Department of Psychology, McMaster University, Hamilton, Ontario, Canada.
Arnold
M G
MG
Chaisson
D J
DJ
Martin
P C
PC
D000375:Aging / Q000502:physiology; D000818:Animals; D005123:Eye / Q000254:growth & development / Q000528:radiation effects*; D014337:Trout / Q000254:growth & development / Q000502:physiology*; D014466:Ultraviolet Rays