Feather performance, walking ability, and behavioral changes of geese in response to different stocking densities

Abstract

In recent decades, goose production has become more specialized and widespread, and rearing geese in plastic wire-floor pens is common in China. This type of rearing pattern is more productive than other rearing patterns since it allows for more birds per square meter. However, it brings some problems due to high stocking density such as poor feather performance and walking ability, and some behavioral changes. This experiment was conducted to preliminarily evaluate the effects of different stocking densities on goose welfare in terms of feather performance, walking ability and behavioral changes. A total of 336 healthy, 28-day-old, male Yangzhou goslings were allotted to 30 plastic wire-floor pens according to five stocking densities (2, 3, 4, 5 and 6 birds/m2), adopting randomised block method. Each treatment was represented by six replicates. Feather performance was assessed by two types of measurements: back-feather damage rate, and feather contamination degree which was carried out by feather scoring. Walking ability was assessed by gait scoring. All birds in each pen were individually scanned for back-feather damage measurement at 42days of age, and individually scored for gait at 68 and 69days of age. One bird from each pen was randomly selected for feather scoring at 69days of age. The higher the feather score and the gait score, the worse the goose welfare. From 60–65days of age, three geese from each pen were randomly selected and tagged for behavioral observation. Results showed that when stocking density was 4 or more birds/m2, standing on one leg (relaxing) behaviour reduced significantly (P≤0.05); when stocking density was 5 or more birds/m2, feather contamination degree (P≤0.05) and preening behaviour (P≤0.05) both increased significantly; when stocking density was 6 birds/m2, the behaviours of lying and feather pecking, and back-feather damage rate all increased (P≤0.05, for all), whereas walking ability declined, which was reflected by the increased proportion of geese with normal gait (P≤0.05) and the decreased proportion of geese with gait problems (P≤0.05). In conclusion, a high stocking density (5 or more birds/m2) led to an increase in feather pecking and poor performances in feather and walking ability, which were harmful to goose welfare and may decrease the quality of goose products. Therefore, based on our experimental conditions, we recommend that the stocking density of geese should be fewer than 5 birds/m2 to ensure relatively good welfare and avoid negative effects. In addition, in our experiment, different stocking densities were in accompany with different group size, in the future, additional studies will be done to explore how stocking density and group size affect goose welfare.