Nicotine induces a conditioned place preference in male Japanese quail (Coturnix japonica)

Visual stimuli may play an important role in the development and maintenance of addiction in humans. Research with a visually-oriented animal model such as Japanese quail (Coturnix japonica) may provide insight into how visual cues contribute to the addiction process. The aim of the current study was to investigate the rewarding properties of nicotine in male Japanese quail using a biased conditioned place preference (CPP) procedure. Adult male quail (N=30) were allowed to freely explore the entire CPP apparatus during a place preference pre-test and time spent in each chamber was measured. During nicotine conditioning sessions, quail were administered nicotine (0.5, 1.0, or 2.0 mg/kg) or saline and were then confined to their initially least preferred chamber. On alternating days, all quail received saline and were confined to their initially preferred chamber. Locomotor activity was assessed in both chambers. The conditioning chambers had yellow or green walls to enhance the visual salience of each context. Following 8 conditioning sessions (4 nicotine; 4 saline), quail were allowed to explore the entire apparatus during a CPP post-test and time spent in each chamber was measured. The results indicated that quail treated with 0.5 and 1.0 mg/kg nicotine significantly increased the amount of time they spent in the nicotine-paired chamber compared to saline controls, suggesting that nicotine produced a CPP. Furthermore, quail treated with 0.5 mg/kg nicotine showed a significant increase in locomotor activity with repeated treatments. The current findings suggest that nicotine may have a rewarding effect in quail and may tentatively suggest that the neuropharmacological mechanisms that mediate CPP for nicotine are conserved in birds.