Masters Thesis

Evaluation of platform enrichments in a commercial broiler house

Consumer demand regarding standards of care, welfare, and production methods are increasingly important for livestock producers. To meet consumer demands, the United States (US) is on a path to increase levels of welfare. Structures added to the environment act as welfare enrichments but establishing scientific understanding of their impact is critical. Therefore, study into platform parameters as they relate to frequency of use is warranted. To understand the platform usage of birds in a conventional (average automated barn where majority of broilers are raised in) broiler house, three replicates of wooden platform prototypes were examined with the following designs: 1) slatted ramps with a vertical angle of 10°, 20°, and 30° (ramp), 2) 0.91 m x 0.3048 m rectangles raised to a height of 7 cm, 10 cm, 13 cm, and 18 cm (height), and 3) 1.22 m x 1.22 m pyramids with one, two, and three levels of steps raised 5cm per step (pyramid). Platforms were placed alternately and centrally in the house at equal distances from the water and feed line. Broiler usage was recorded with cameras positioned above the platforms in a commercial broiler house. Conventional broilers had unrestricted access to the platforms from the entire grow out cycle of two flocks. Platform usage was recorded daily as five second interval recordings at five time points on d2 to d44 at: 330, 930, 1330, 1730 and 2130. Birds were considered to be using the platform if observed to be physically on the platform. The platform usage frequency was calculated as (number of birds using the platform) / (the calculated maximum number of birds that could occupy the platform). Adjusted frequencies were analyzed as the percentage of bird usage based on the available surface area of the platform. Usage amongst platform types were analyzed across days using an ANOVA in JMP v.11. Significance was evaluated at P ≤ 0.05. Interestingly, while the pyramid platform designs had the highest frequency of use when considering raw counts, they had the lowest frequency of use when using adjusted counts (P <0.05). Height platforms had the highest usage frequency compared to all other platforms (P <0.05). Considering design variables and platform surface area are critical when developing enrichments for conventional broiler facilities.

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