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Biomedical subjects

G J Fischer

Publications and source records attributed to G J Fischer.

34 records · Page 2Linked to original sources
PubMed1975

Prehatch color stimulation effects on color pecking preferences and color discrimination learning in white leghorn chicks.

Four experiments assessed the effects of stimulating chick embryos with colored light at 2 intensity levels. Both posthatch color pecking preferences (Experiments 1 and 2) and color discrimination learning (Experiments 3 and 4) were unaffected. These results affirm and extend a prior finding of no pre- and posthatch colored light stimulation effect on posthatch color preferences in ducklings. The color pecking preferences found replicated prior findings with chicks. However, they differed from the approach color preferences observed in color discrimination learning.

Animals↗
PubMed1975

Color pecking preferences in White Leghorn chicks.

Studies of color pecking preferences in newly hatched chicks (Gallus domesticus) have shown unimodal preference in the orange region of the spectrum or bimodal preferences at blue and orange. In the present study, dark-harched White Leghorn chicks were tested in darkness with targets illuminated at 1 or 3 radiant intensity levels. Results showed the least amount of pecking at green (541 nm.) and peak preferences in blue-violet and orange-red regions. Findings were similar when other dark-hatched chicks were tested in the light (Experiment 2). Overall, findings suggest unlearned pecking preferences for short and long wavelengths, with minimums at green. Possible evolutionary and photochemical bases for such a bimodal wavelength preference function were discussed. Since bimodality was unaffected by target intensity and background, these variables probably do not account for the unimodal function reported by others.

Aging↗