Effects of a partially perforated flooring system on animal-based welfare indicators in broiler housing

Abstract

Alternative flooring designs in broiler housing have been the subject of intensive research. Research comparing different floor types with a focus on animal-based welfare indicators might be of special interest to meet the animal's needs. This case-control study investigated the effect of a partially perforated vs. a littered flooring system on health- and behavior-based welfare indicators of fast-growing Ross 308 broilers. Furthermore, production performance was assessed. The experimental barn was partially (50%) equipped with a perforated floor directly underneath the feeders and water lines accessible by perforated ramps. Conventional wood shavings were used in the control barn, as usual in practice. There were 4 fattening periods (repetitions) of 31 to 32 D performed with 500 animals per barn (final density of 39 kg m^-2). Beside the flooring system, management conditions were identical. Health- and behavior-based welfare indicators were assessed weekly. Production performance indicators were measured continuously during animal control. During the avoidance distance test, animals were less fearful on day 21 (P = 0.010) and tended to be less fearful on day 28 (P = 0.083) in the barn with the partially perforated flooring system compared to the littered control barn. More animals around the novel object were also assessed in the barn with the partially perforated flooring system during the novel object test on day 1 (P < 0.001) and a tendency was found on day 28 (P = 0.064). Results showed that the partially perforated flooring system had a positive influence on foot pad dermatitis from day 14 (all P ≤ 0.007) and hock burn on day 28 (P < 0.001). With regard to the production performance, animals showed no differences in final body weight for both floor types. In this study, the partially perforated flooring system had a positive effect on animal health and behavior as indicated by welfare indicators without a reduction in production performance.

Keywords: alternative flooring; animal behavior; animal health; animal welfare; broiler production.

Figure 1

Illustration of a partially perforated flooring system in the area of feed and water supply in the experimental barn (A) compared to a littered flooring system in the control barn (B).

Figure 2

Layout of 2 broiler housing systems; a partially perforated floor underneath the feeders and water lines with access to a littered area in the experimental barn (A) and a total littered floor in the control barn (B).

Figure 3

Layout of 2 broiler housing systems with 2 different floor types including measurement positions for the litter quality, avoidance distance test (ADT), air temperature (Temp), and relative air humidity (RH).

Figure 4

Mean number of animals in arm's reach of the observer during the avoidance distance test (ADT) with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 48 values per assessment day and barn). Significant differences are marked by asterisks: ∗∗P < 0.01. Tendencies are marked by circles: °0.05 < P < 0.10.

Figure 5

Mean number of animals around the novel object (NO) during the novel object test (NOT) with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 192 measurements per assessment day and barn). Significant differences are marked by asterisks: ∗∗∗P < 0.001. Tendencies are marked by circles: °0.05 < P < 0.10.

Figure 6

Mean scores of litter quality with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 16 to 20 litter samples per assessment day and barn).

Figure 7

Mean scores of foot pad dermatitis with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 200 animals per assessment day and barn). Significant differences are marked by asterisks: ∗∗P < 0.01, ∗∗∗P < 0.001.

Figure 8

Mean scores of hock burn with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 200 animals per assessment day and barn). Significant differences are marked by asterisks: ∗∗∗P < 0.001.

Figure 9

Mean scores of plumage cleanliness with standard error from broilers kept on 2 different floor types measured weekly over 4 different fattening periods (repetitions; n = 200 animals per assessment day and barn).

Figure 10

Average daily air temperature (Temp) and relative air humidity (RH) over 4 different fattening periods (repetitions) from broiler houses with 2 different flooring systems (n = 1,920 measurement values per day and barn).