INVESTIGADORES
ZAGARESE Horacio Ernesto
artículos
Título:
How much does ultraviolet radiation contribute to the feeding performance of rainbow trout (Oncorhynchus mykiss) juveniles under natural illumination?
Autor/es:
VANINA ROCCO,; PABLO BARRIGA, JUAN; HORACIO ZAGARESE; MARIANA LOZADA,
Revista:
ENVIRONMENTAL BIOLOGY OF FISHES
Referencias:
Año: 2002 vol. 63 p. 223 - 228
ISSN:
0378-1909
Resumen:
Most
research on environmental effects of ultraviolet radiation (UVR) has focused on
its potential negative consequences. However, natural UVR can also be
beneficial to living organisms (e.g., vitamin D synthesis, UV vision, germicide
activity). UV vision has been demonstrated in a variety of animals including
several invertebrates and vertebrates.
Juvenile rainbow trout, Oncorhynchus mykiss, has a retinal
photoreceptor, which is sensitive to UVR between 360 and 370 nm. Among other
functions, UV vision has been proposed to contribute to prey detection by
enhancing the contrast between the prey and its background. We performed a
series of feeding experiments with juvenile rainbow trout and several
zooplankters as prey. The fish were allowed to feed either under full solar
radiation, or under solar radiation from which the UV component had been
removed using a long-pass cut off filter. We found that the removal of UV
wavelengths had no effect on the number of prey eaten or on the preference for
particular food items. This is contrary to published studies reporting prey
detection enhancement mediated by UV vision in rainbow trout. This disparity in
the results may be due to our use of natural radiation instead of artificial UV
sources, in which the visible component is poorly represented. Although our
results do not disproof the presence of UV vision in juvenile rainbow trout,
they do cast doubts about its significance in enhancing feeding performance in
a natural light environment.