Correlation search between growth performance and flock activity in automated assessment of Pekin duck stocking density

In recent years, duck production has been changed from conventional free range and open water outdoors to confinement in birdhouses. And the concept of animal welfare in high stocking density begins to be accepted in China. The search of the relationship between growth performance and flock activity of Pekin ducks with different stocking densities using camera surveillance has great potential as an aid to improving flock management. The aim of this study was to determine the impact of stocking density on growth performance and activity of Pekin duck flocks. Furthermore, the correlation between growth performance and the activity of White Pekin ducks was investigated. Eventually, it will generate an automatic method for monitoring growth performance and stocking density evaluation of Pekin ducks. All ducks (24 days of age, n = 1200) were randomly allotted into 5 stocking density groups of 5 ducks/m(2), 6 ducks/m(2), 7 ducks/m(2), 8 ducks/m(2), 9 ducks/m(2), with 6 replicates for each group. One group was selected for monitoring the activity of ducks using video recording system. The optical flow measures were extracted to describe the duck flock activity statistically using night video data. On the 24 and 42 days of age, sample collection was conducted for initial and final body weight (BW) measurements respectively. The results showed that the stocking density had significant effects on final BW and weight gain (P < 0.05), but not on feed intake and feed/gain (P > 0.05). The stocking density also had significant effects on mean and variance of optical flow produced by duck flock activity throughout the experimental duration. In the last, a significant relation was found between the mean of optical flow and final BW (r(2) = +0.87). These results show that the proposed method has potential in automatic growth monitoring and stocking density management of Pekin ducks. It can cut out the bio-security risk and animal stress of having people actually visiting duck houses.