Latent cognitive effects from low-level polychlorinated biphenyl exposure in juvenile European starlings (Sturnus vulgaris).

Abstract

Ecotoxicology research on polychlorinated biphenyl (PCB) mixtures has focused principally on short-term effects on reproduction, growth, and other physiological endpoints. Latent cognitive effects from early life exposure to low-level PCBs were examined in an avian model, the European starling (Sturnus vulgaris). Thirty-six birds, divided equally among 4 treatment groups (control = 0 µg, low = 0.35 µg, intermediate = 0.70 µg, and high = 1.05 µg Aroclor 1254/g body weight), were dosed 1 d through 18 d posthatch, then tested 8 mo to 9 mo later in captivity in an analog to an open radial arm maze. Birds were subject to 4 sequential experiments: habituation, learning, cue selection, and memory. One-half of the birds did not habituate to the test cage; however, this was not linked to a treatment group. Although 11 of the remaining 18 birds successfully learned, only 1 was from the high-dosed group. Control and low-dosed birds were among the only treatment groups to improve trial times throughout the learning experiment. High-dosed birds were slower and more error-prone than controls. Cue selection (spatial or color cues) and memory retention were not affected by prior PCB exposure. The results indicate that a reduction in spatial learning ability persists among birds exposed to Aroclor 1254 during development. This may have implications for migration ability, resource acquisition, and other behaviors relevant for fitness.

• Authors: Alexander R D Zahara, Nicole L Michel, Leanne M Flahr, Leanne E Ejack, Christy A Morrissey
• Journal: Environmental toxicology and chemistry (Environ Toxicol Chem) Vol. 34 Issue 11 Pg. 2513-22 (Nov 2015) ISSN: 1552-8618 [Electronic] United States
• PMID: 26033510 (Publication Type: Journal Article)
• Copyright: © 2015 SETAC.

Chemical References

• Polychlorinated Biphenyls

Topics

• Animals
• Behavior, Animal (drug effects)
• Brain (drug effects, physiology)
• Cognition (drug effects)
• Female
• Learning (drug effects)
• Male
• Polychlorinated Biphenyls (toxicity)
• Starlings (growth & development, physiology)