Avian Circadian Research
Entrainment of Circadian Rhythms of the Pinealectomized Pigeon, Columba livia, with Physiological Amounts of Infused Melatonin
 

Figure 6: Peak blood melatonin levels from P-X/melatonin infused pigeons in DD. Pigeons in the 0 uglhr group were P-X birds that received either vehicle only or nothing at all. Top panel - Blood samples taken in DD via an indwelling cannula every two hours for 24 hours. Bottom panel - Blood samples taken in DD by venipuncture every 6 hours for 24 hours.