New project in 2015: Research on tail biting and tail docking in pigs
Tail biting is a problem in growing-finishing pigs, which can cause considerable economic loss to pork producers and major complications for the welfare of pigs. Tail biting is considered an abnormal behavior due to stress and frustration of the pig. Many factors may contribute to tail biting, including genetics, gender and age of the pig, nutrient deficiency, stocking density (crowding), poor air quality, uncomfortable thermal environment (too hot, too cold, or draft), improper feeding, watering or lighting method, floor type, and lack of rooting substrates. Thus, a breakout of tail biting can be triggered by multiple factors. Once it has occurred, the tail biting behavior can escalate rapidly, and it is difficult to prevent further tail biting in the pen. Preventions prior to a breakout are necessary to avoid losses and implications caused by tail biting.
The common prevention method for tail biting is tail docking. While tail docking reduces the incidence of tail biting, it does not eliminate the problem. The average prevalence of tail biting, as measured by percent pigs with damaged tails, is estimated to be around 6-10% for pigs with intact tails and 3-5% for pigs with docked tails (EFSA, 2007). In addition, tail docking is a painful procedure for the pig and it is coming under scrutiny because of animal welfare concerns. To address these concerns, the European Union (EU) Directive 91/630/EEC recommended that tail docking on a routine basis should be prohibited. In response to the EU Directive, Several countries in Europe, including Sweden, Finland, and Switzerland have banned tail docking.
In order to maintain U.S. pork producers' competitiveness in global markets, and thereby, enhance sustainability of the U.S. swine industry, the National Pork Board recently funded our proposal titled 'Tail-biting in growing-finishing pigs'. Given that the incidence of tail biting among pigs with intact tails is less than 10%, we ask the question: "Is it necessary to dock every pig's tail to prevent tail biting?" Since tail biting is caused by tail biters (pigs that bite and injure other pigs' tails) in a group, then research on tail biting should focus on understanding tail biters. However, most previous studies on tail biting have been focused on victimized pigs (pigs with damaged tails).
If we could identify potential tail biters and intervene through management prior to outbreaks of tail biting, we might be able to prevent tail biting in a way that is more efficient and animal welfare-friendly than tail docking. So, the overall objective of this project is to identify an effective and animal welfare-friendly measure to prevent tail biting in pigs. First, we will evaluate the efficacy of the current preventative measure, tail docking by quantifying the impact of tail docking on tail biting behavior and growth performance of pigs. Then, we will investigate the development of tail biting behavior with an aim of predicting tail biters. This will allow us to explore an alternative measure of prevention by managing tail biters.
Finally, we will determine the effect of tail biting on pain, stress, and weight gain of victimized pigs and tail biters. This will help us not only quantify the negative impact, but understand the underlying mechanism of tail biting. We are very excited about initiating this new project. The animal trials will be conducted in 2015. We hope to report our preliminary results to you by the end of 2015.
Reviewed by Wayne Martin