Feeding behaviour and daily energy expenditure of domesticated budgerigars (Melopsittacus undulatus): Influence of type of housing and vertical position of the feeder

Obesity is a common health problem in captive budgerigars (Melopsittacus undulatus). The welfare of budgerigars would be increased in a housing system limiting obesity. The aim of this study was to measure the influence of 3 different housing types on feeding behaviour and energy balance. Fifty-four budgerigars (Melopsittacus undulatus) were housed in male-female pairs in cages and aviaries with the feeders 37 cm under the perches in cages and in one type of aviary, and 120 cm under the perches in the other type of aviary during 3 series of 5 weeks. The effects of these different treatments were evaluated by 15-min live behavioural observations, 10–14-h feeder video recordings, single Doubly Labelled Water (DLW) measurements, and biometric measures. The treatments had an effect on the proportion of time spent feeding, the food consumption, the behaviours performed in the arbitrarily defined vertical levels, the flight activity, the feeding frequency, and the duration of feeding bouts. There was no effect on body mass change or Daily Energy Expenditure (DEE). The less time they spent during one feeding bout, the more often they fed. The longer the perch–feeder distance was, the less time the birds spent feeding. DEE strongly correlated with the condition (i.e. body mass/(tarsus length)3). Courtship feeding was associated with a significant increase of DEE in males. The last series performed in summer strongly differed from the two previous series performed in winter and spring. The birds gained mass in the third series only, and their DEE was also significantly lower. This serial effect was greater than the influence of the treatment. From a welfare perspective, housing conditions may modify the behaviour but may not reduce the risk of obesity of budgerigars. Instead, individual behaviour of the birds (especially courtship behaviour) as well as unknown external factors were important.