Towards a Norwegian pork production free of tail biting

Tail biting is a serious welfare issue in pig production and an economic challenge for the farmer. The aim of this project is therefore to reduce tail biting incidences in Norway and in other countries where Norsvin has genetics. The project has been split in two parts; one part about environmental factors and one part including the genetic perspective of tail biting. The project conducted various studies to investigate environmental effects on tail biting. Among other project also have had a close collaboration with NMBU. In the work of identifying risk factors affecting tail biting behaviour, NMBU has published two papers. The main conclusion from this work is that pigs that do not feel well or healthy, tend to carry out manipulative behaviours, such as ear- or tail biting, more frequently. A feeding trial has also been carried out, to see if a tailor-made feed to prevent tail biting (based on previous literature) could reduce the incidence of tail biting. Based on the material from the feeding trial, it could not be concluded that this specific feed had any effect on the occurrence of tail biting in this experiment. For genetic studies of traits, information and recording of the traits on an animal level is crucial. The project therefore developed a new function in our recording system for recording tail biting. This is crucial information for implementing tail biting as a part of our breeding goal. A genome-wide association study has been carried out. Significant effects of SNPs on tail biting behaviour were found on two different chromosomes, and here, genes within the same gene families as genes related to traits such as Alzheimer disease, mental disabilities, hyperactivity in mice, depression and autism were located. Genetic variation in the trait ?being tail bitten? is also estimated. Still, there is a small fraction of the phenotypic variation that could be explained by the genes of the animal. A genetic correlation to growth was identified, meaning that animals with a high genetic potential for high growth has a lower genetic potential of becoming a victim of tail biting. The project has identified that both environment and genetics influence the incidence of tail biting. Still, tail biting is a complex behaviour, affected by multiple factors. Further, there is huge between-farm variation. Which measures against tail biting that is working in one herd, is not necessarily what works in another herd. The most important measures against tail biting has to be taken on a herd level, while breeding to prevent tail biting will contribute to reduce the incidence in a long-term perspective.

Prosjektet har gitt fokus på halebiting som velferdsproblem i svinenæringen. Prosjektet har samlet kunnskap og formidlet dette i foredrag og på papir. Dette har gitt næringen mulighet til å ta i bruk teoretisk kunnskap i praksis. Forekomst av halesår har gått ned siden 2017. Dette er et resultat av flinke og fremoverlente produsenter, som ønsker å lære og setter kunnskap ut i praksis. For Norsvin har prosjektet bidratt til verdiskaping. Norsvin er verdensledende når det gjelder avlsarbeid på helse og velferdsegenskaper. Det er viktig å beholde denne posisjonen i markedet. Prosjektet har vist at forekomst av halesår er arvelig og kan avles mot. Fremtidige genetiske endringer er et langsiktig tiltak for å forebygge halebiting. Dette er tiltak som anses for å være viktige og kan øke salget av Norsvins genetikkprodukter internasjonalt. En slik seleksjon vil øke verdiskapningen i den enkelte besetning, ettersom halesår medfører økonomiske konsekvenser gjennom økte variable kostnader.

The main objective of this project is to use current and new methodology to investigate an increasing problem in pork production in Norway; tail biting. The project will identify risk factors related to tail biting in Norwegian grower-finisher production and develop management protocols for the producers. The project will develop methods for including tail biting in our breeding program to avoid further development of the problem. This will be achieved through large-scale recording of farm environment and management in grower-finisher productions, identified based on tail biting recorded in abattoirs, to identify risk factors for tail biting. Further, large-scale recording of tail biting will be recorded on Delta, the boar testing station at Norsvin, and in commercial crossbred herds. In one herd, a feed trial will be conducted. This large-scale recording and feed trial will be used to monitor tail biting in Norsvin's breeds, establish a platform for individual routine recording of phenotypes for breeding purposes and create feed advice to prevent tail biting. Potential proxy traits for tail biting will be investigated for implementation in the breeding goal, such as health- and metabolic indicators. Hopefully, video recording of pens will be available for phenotyping of potential tail biting-related traits (through a different project). Statistical tools for implementation of tail biting will be developed. This includes use of phenotypes and genomic information from commercial crossbred animals in combination with genomic selection and genetic models including social interaction between animals within pen. This project will provide us with new statistical methods and both phenotypic and genomic information that will be used in selective breeding to produce a top quality genetic product on behalf of all Norwegian pig producers. The project will contribute with vital information and research on a prominent issue from a political, social and ethical point of view.