Interactive Rooting Towers and Behavioural Observations as Strategies to Reduce Tail Biting on Conventional Pig Fattening Farms

SIMPLE SUMMARY: In Europe, tail docking in swine is prohibited as a routine measure, but the risk of tail biting outbreaks is increased in pigs with intact tails. An important measure to minimise this risk is the provision of enrichment material, which is challenging in conventional confinement buildings with fully slatted floors. In this study, the effect of an interactive straw-filled rooting tower was tested under field conditions with respect to the prevalence of tail lesions and behaviour. Although tail biting could not be prevented in pigs with intact tails, tail lesions were less frequent and less severe compared to pigs which had no access to straw but were only exposed to the stationary tower as a placeholder (control group). Increased manipulation of the rooting tower around feeding times reflected the typical porcine ambition for simultaneous feed uptake in a group. In addition, tail manipulation was less common than head manipulation in pigs with access to the interactive tower. The rooting tower can be used in addition to other measures as a preventive and intervening tool to deal with tail biting in pigs with intact tails, and on farms with fully slatted floors. ABSTRACT: Eight pens (25 pigs/pen; n = 200) provided with an interactive straw-filled rooting tower (experimental group) and five pens (25 pigs/pen; n = 125) with a stationary (fixed) tower without straw (control group) were compared within three fattening periods on a conventional farm with fully slatted flooring. The effectiveness of the tower to trigger favourable behaviour in feeding and outside feeding periods was assessed. The incidence of deep tail injuries was lower in the experimental group (experimental group: Odds Ratio 0.3, p < 0.001) and was influenced by the batch (Odds Ratio: 2.38, p < 0.001) but not by pen and sex. In spring, most pens were excluded due to severe tail biting. Tail injury scores were more severe in the control group in weeks 5, 6 and 7 compared to the experimental group (p = 0.002, p < 0.001, p < 0.001, respectively). Tower manipulation was more frequent during feeding compared to outside feeding time (p = 0.002). More head than tail manipulation occurred in the experimental group (p = 0.03). The interactive tower as the only measure was not appropriate to reduce tail biting sufficiently in pigs with intact tails on a conventional fattening farm. Of high priority to prevent tail biting outbreaks was the early detection of biting pigs.