Efficacy of straw-filled rooting tower for prevention of tail injuries in fattening pigs

Tail biting outbreaks rate among the major threats in pig production. To prevent or at least minimize tail biting docking is routine practice in Germany, although it contradicts the Council Directive 2008/120/EC. Many factors, like climate, general health status, stocking density, food and water supply and especially insufficient environmental enrichment have a major impact on the tail biting incidence. In the present study, a straw-filled rooting tower (“Düsser Wühlturm”) was tested for avoiding tail biting in undocked fattening pig groups.

The study was performed in a conventional fattening farm during three fattening periods. A total of 325 pigs with undocked tails ware observed until slaughter using a tail scoring system and a partial behavioral ethogram. In 8 pens straw-filled and movable rooting towers and in 5 pens empty and fixed rooting towers (“dummies”) were installed to provide the same place for every pig. 25 pigs were allocated in a pen. During the first ten weeks of fattening period, tails were scored once a week, while behavior of pig groups was analyzed every second week by video surveillance covering 110 minutes per day. Evaluated parameters were: interactions a) with the rooting tower, b) with stable enrichments, c) with other pigs head, d) with other pigs torso, e) with other pigs tail, and f) with other pig legs.

Tail biting outbreaks occurred in 25 % of pens equipped with a straw-filled rooting tower and in 80 % of pens with a dummy. No differences in the kind of tail lesions (deep skin lesions, tail losses, acute bleeding, swelling) were observed. Neither significant differences between both groups were found summarizing interactions on all body regions. Compared to tail manipulation, head manipulations were recorded most often, especially during feeding as well as in periods between feeding times in pens with the straw-filled rooting tower (p=0.03). In general, more interaction with the straw-filled rooting tower was observed than with the dummy.

The straw filled rooting tower (“Düsser Wühlturm”) combines advantages of a spatial structuring object and enrichment. Although it is of interest for pigs during the whole fattening period, in this study it was found to be not suitable for prevention of tail biting in fattening pigs with undocked tails.

Disclosure of Interest: None Declared.