Lahrmann H P, Busch M E, D'Eath R B, Forkman B, Hansen C F
1SEGES,Danish Pig Research Centre,Axeltorv 3,1609 Copenhagen V,Denmark.
2SRUC,West Mains Road,Edinburgh EH9 3JG,UK.
Animal. 2017 Oct;11(10):1825-1831. doi: 10.1017/S1751731117000490. Epub 2017 Mar 15.
The vast majority of piglets reared in the European Union (EU) and worldwide is tail docked to reduce the risk of being tail bitten, even though EU animal welfare legislation bans routine tail docking. Many conventional herds experience low levels of tail biting among tail docked pigs, however it is not known, what the prevalence would have been had the pigs not been tail docked. The aim of this study was to compare the prevalence of tail lesions between docked and undocked pigs in a conventional piggery in Denmark with very low prevalence of tail biting among tail docked pigs. The study included 1922 DanAvl Duroc×(Landrace×Large White) female and castrated male pigs (962 docked and 960 undocked). Docked and undocked pigs were housed under the same conditions in the same room but in separate pens with 20 (±0.03) pigs/pen. Pigs had ad libitum access to commercial diets in a feed dispenser. Manipulable material in the form of chopped straw was provided daily on the floor (~10 g/pig per day), and each pen had two vertically placed soft wood boards. From weaning to slaughter, tail wounds (injury severity and freshness) were scored every 2nd week. No clinical signs of injured tails were observed within the tail docked group, whereas 23.0% of the undocked pigs got a tail lesion. On average, 4.0% of the pigs with undocked tails had a tail lesion on tail inspection days. More pens with tail lesions were observed among pigs weighing 30 to 60 kg (34.3%; P<0.05) than in pens with pigs weighing 7 to 30 kg (13.0%) and 60 to 90 kg (12.8%). Removal of pigs to a hospital pen was more likely in undocked pens (P<0.05, 47.7% undocked pens and 22.9% docked pens). Finally, abattoir meat inspection data revealed more tail biting remarks in undocked pigs (P<0.001). In conclusion, this study suggests that housing pigs with intact tails in conventional herds with very low prevalence of tail biting among tail docked pigs, will increase the prevalence of pigs with tail lesions considerably, and pig producers will need more hospital pens. Abattoir data indicate that tail biting remarks from meat inspection data severely underestimate on-farm prevalence of tail lesions.
在欧盟（EU）以及全球范围内饲养的绝大多数仔猪都进行了断尾，以降低被咬尾的风险，尽管欧盟动物福利立法禁止常规断尾。许多传统猪群中，断尾猪的咬尾情况较少，然而，如果猪没有断尾，咬尾的发生率会是多少却无人知晓。本研究的目的是比较丹麦一个传统养猪场中断尾猪和未断尾猪的尾部损伤发生率，该养猪场中断尾猪的咬尾发生率极低。研究包括1922头DanAvl杜洛克×（长白猪×大白猪）的母猪和去势公猪（962头断尾猪和960头未断尾猪）。断尾猪和未断尾猪在同一房间的相同条件下饲养，但分栏饲养，每栏20（±0.03）头猪。猪可通过饲料分配器自由采食商业日粮。每天在地面上提供切碎的稻草形式的可操作性材料（约每头猪每天10克），每个猪栏有两块垂直放置的软木板。从断奶到屠宰，每隔一周对尾部伤口（损伤严重程度和新鲜度）进行评分。断尾组未观察到尾部受伤的临床症状，而23.0%的未断尾猪出现了尾部损伤。在尾部检查日，平均有4.0%的未断尾猪有尾部损伤。体重30至60公斤的猪栏中观察到尾部损伤的猪栏更多（34.3%；P<0.05），高于体重7至30公斤（13.0%）和60至90公斤（12.8%）的猪栏。未断尾猪栏的猪被转移到医院猪栏的可能性更大（P<0.05，未断尾猪栏为47.7%，断尾猪栏为22.9%）。最后，屠宰场肉类检验数据显示，未断尾猪的咬尾记录更多（P<0.001）。总之，本研究表明，在断尾猪咬尾发生率极低的传统猪群中饲养未断尾猪，将显著增加尾部有损伤猪的发生率，养猪生产者将需要更多的医院猪栏。屠宰场数据表明，肉类检验数据中的咬尾记录严重低估了农场中尾部损伤的发生率。
