All posts by Marc

PhD defence on preventing tail biting in pigs online Monday April 9, 2018

Dear all,

I will defend my PhD on Monday, April 9 at 13.00 (UTC +2, due to summertime CEST).

The title is “Two strategies to prevent tail damage in finishers: removal of risk factors and early detection”.

The defence will be in English.

It will begin with a 45 min lecture, a short break and then continue with questions from the opponents until latest 16.00.

The opponents are Emerita Professor Sandra Edwards and Dr. Rick D’Eath.

I have arranged that the defence will be live streamed. It is possible for everyone to join and it is very easy:

  • You will need Java, Adobe Flash Player and do not use the web browser Google Chrome for this
  • Go to vc.au.dk
  • Choose “Live Videos
  • Choose the one named “Foulum Auditorium
  • Now you should be connected and be able to choose between seeing the room, the power point presentation more closely or a combination if you wish

Also, if you know of anyone that could be interested, please just forward this email. Everyone is welcome!

Looking forward to seeing all of you in the future!

Best wishes,

Mona Lilian Vestbjerg Larsen

Curious pigs

A review of tail docking in farm animals

The long and short of it: A review of tail docking in farm animals
Mhairi A. Sutherland, Cassandra B. Tucker, 2011. Applied Animal Behaviour Science 135: 179-191

Abstract

Tail docking involves amputating a portion of the tail for a variety of reasons. We review the scientific evidence for the rationale for tail docking, a description of the different methods used, the pain response to the procedure and the effectiveness of pain alleviation, and, finally, the alternatives to tail docking and policy regarding the practice. We focus on the three main agricultural species that are tail docked as a management practice: pigs, sheep, and dairy cattle. Methods of tail docking include cutting with a knife or scalpel, cutting with a hot docking iron, or application of a constrictive rubber ring. All methods are commonly performed without analgesia or anaesthesia, and all likely result in some degree of pain. As with any procedure that alters the integrity of an animal, it is important to consider the rationale behind docking in order to evaluate if it is necessary. Tail docking in pigs is routinely conducted on commercial swine farms because it can reduce the incidence of tail biting, an injurious and undesirable behaviour. Both behavioural and physiological changes indicate that tail docking is painful in pigs, but until robust and consistent methods for preventing tail biting are identified, this procedure is likely to continue as a management practice. This approach is reflected in public policy about the procedure. There is both behavioural and physiological evidence that tail docking is painful for sheep; both responses are reduced when pain relief is provided. Prevention of fly strike is the primary reason given for tail docking sheep, but the scientific evidence to support this rationale is surprisingly sparse. Further research is required to justify tail docking of sheep as a routine practice. Dairy cattle are docked because this practice is thought to improve cow cleanliness and udder health, however, there is no scientific evidence supporting this rationale. Tail docking cattle results in relatively few behavioural or physiological indicators of pain, but docked cows are unable to effectively remove flies from their hind end. The practice of tail docking dairy cattle is banned, discouraged or declining in most industrialized countries except the US. The long-term pain associated with tail docking is not well understood in pigs, sheep or cattle. In cases where tail docking may be justified by demonstrated benefits for the animal (possibly in case of pigs and sheep), further research is needed to find either practical alternatives or ways to alleviate the pain associated with this procedure.

Prophylactic use of antibiotics affects piglet welfare

Do weaner pigs need in-feed antibiotics to ensure good health and welfare?
By Alessia Diana, Edgar G. Manzanilla, Julia A. Calderon Diaz, Finola C. Leonard,
Laura A. Boyle. 2017. PlosOne.

Abstract

Antibiotics (AB) are used in intensive pig production systems to control infectious diseases
and they are suspected to be a major source of antibiotic resistance. Following the ban on
AB use as growth promoters in the EU, their prophylactic use in-feed is now under review.
The aim of this study was to evaluate the effect of removing prophylactic in-feed AB on pig
health and welfare indicators. Every Monday for six weeks, a subset of 70 pigs were
weaned, tagged and sorted into two groups of 35 pigs according to weight (9.2 ± 0.6 kg). AB
were removed from the diet of one group (NO, n = 6) and maintained in the other group (AB,
n = 6) for nine weeks. Ten focal pigs were chosen per group. After c. five weeks each group
was split into two pens of c.17 pigs for the following 4 weeks. Data were recorded weekly.
Skin, tail, ear, flank and limb lesions of focal pigs were scored according to severity. The
number of animals per group affected by health deviations was also recorded. The number
of fights and harmful behaviours (ear, tail bites) per group was counted during 3×5min
observations once per week. Data were analysed using mixed model equations and binomial
logistic regression. At group level, AB pigs were more likely to have tail (OR = 1.70; P =
0.05) but less likely to have ear lesions than NO pigs (OR = 0.46; P<0.05). The number of
ear bites (21.4±2.15 vs. 17.3±1.61; P<0.05) and fights (6.91±0.91 vs. 5.58±0.72; P = 0.09)
was higher in AB than in NO pigs. There was no effect of treatment on health deviations and
the frequency of these was low. Removing AB from the feed of weaner pigs had minimal
effects on health and welfare indicators.

Indirect Genetic Effects for Growth Rate in Domestic Pigs Alter Aggressive and Manipulative Biting Behaviour

Indirect Genetic Effects for Growth Rate in Domestic Pigs Alter Aggressive and Manipulative Biting Behaviour
By Irene Camerlink, Winanda W. Ursinus, Piter Bijma, Bas Kemp, J. Elizabeth Bolhuis. 2015. Behavior Genetics 45: 117–126.

Indirect genetic effects (IGEs) are heritable effects of an individual on phenotypic values of others, and may result from social interactions. We determined the behavioural consequences of selection for IGEs for growth (IGEg) in pigs in a G × E treatment design. Pigs (n = 480) were selected for high versus low IGEg with a contrast of 14 g average daily gain and were housed in either barren or straw-enriched pens (n = 80). High IGEg pigs showed from 8 to 23 weeks age 40 % less aggressive biting (P = 0.006), 27 % less ear biting (P = 0.03), and 40 % less biting on enrichment material (P = 0.005). High IGEg pigs had a lower tail damage score (high 2.0; low 2.2; P = 0.004), and consumed 30 % less jute sacks (P = 0.002). Selection on high IGEg reduced biting behaviours additive to the, generally much larger, effects of straw-bedding (P < 0.01), with no G × E interactions. These results show opportunities to reduce harmful biting behaviours in pigs.

Two-level pen may be feasible option to increase space allowance and to create functional areas in a piglet pen

Use of space and behavior of weaned piglets kept in enriched two-level housing system
By Michaela Fels, Franziska Lüthje, Alice Faux-Nightingale & Nicole Kemper. 2018 Journal of Applied Animal Welfare Science

In this study, the possibility of introducing an elevated platform to a piglet pen was explored as a way of increasing available space and creating functional areas. On the platform, nine different manipulable materials were offered. In four batches, 40 weaned piglets were kept for five weeks in the two-level pen. Video recordings were taken two days per week. In the afternoon, more piglets were on the platform than in the morning or at night (7.2 ± 0.1 vs. 4.9 ± 0.1 vs. 0.6 ± 0.1 piglets/5 minutes; p < .05). The area under the platform was preferred more in the morning and at night than in the afternoon (18.5 ± 0.1 vs. 21.6 ± 0.2 vs. 12.5 ± 0.1 piglets/5 minutes; p < .05). Up to 36 piglets were counted there simultaneously, mainly in the recumbent position. On and under the platform, air velocity and ammonia concentration were within the recommended ranges. The study concluded that a two-level pen is a feasible option to increase space allowance and to create functional areas in a piglet pen.

Weaned littermate piglets seem less socially connected and prone to becoming tail-biting victims

Understanding Tail-Biting in Pigs through Social Network Analysis

By Yuzhi Li, Haifeng Zhang, Lee. Johnston and Wayne Martin 2018. Animals 2018, 8(1), 13

The objective of this study was to investigate the association between social structure and incidence of tail-biting in pigs. Pigs (n = 144, initial weight = 7.2 ± 1.57 kg, 4 weeks of age) were grouped based on their litter origin: littermates, non-littermates, and half-group of littermates. Six pens (8 pigs/pen) of each litter origin were studied for 6 weeks. Incidence of tail injury and growth performance were monitored. Behavior of pigs was video recorded for 6 h at 6 and 8 weeks of age. Video recordings were scanned at 10 min intervals to register pigs that were lying together (1) or not (0) in binary matrices. Half weight association index was used for social network construction. Social network analysis was performed using the UCINET software. Littermates had lower network density (0.119 vs. 0.174; p < 0.05), more absent social ties (20 vs. 12; p < 0.05), and fewer weak social ties (6 vs. 14, p < 0.05) than non-littermates, indicating that littermates might be less socially connected. Fifteen percent of littermates were identified as victimized pigs by tail-biting, and no victimized pigs were observed in other treatment groups. These results suggest that littermates might be less socially connected among themselves which may predispose them to development of tail-biting.

Curly pig tail farming in Finland and Italy (two EC videos)

EU legislation on the welfare of pigs (Council Directive 2008/120/EC laying down minimum standards for the protection of pigs) does not allow routine tail-docking and requires farmers to provide to their pigs “manipulable material” such as straw, hay or sawdust.
To better inform farmers how to prevent routine tail docking, the Commission developed educational materials. The two videos present success stories in achieving the goal of rearing not-tailed pigs.

A Finnish farming with an intensive system rearing piglets with intact, curly tails.

An Italian farmer proud of rearing curly tails on straw

Chains as enrichment for pigs (Book chapter with supplement)

Chains as proper enrichment for pigs (incl. supplement) (Book chapter in Advances in Pig Welfare, M Spinka (Editor), Elsevier).

Rearing pigs in barren conditions reduces their welfare. Enrichment of pig pens is needed to allow the performance of species-specific natural behaviour like rooting. A metal chain provides rather limited enrichment, but when presented in an optimized way, may substantially improve the welfare of conventionally reared pigs in a most feasible way. The short metal chain can be optimize into the branched chain design. This is a long anchor-chain type chain reaching til floor level, with 2 or 3 shorter chain branches at nose height, and 1 such a branched chain being provided for every 5 pigs in the pen.

The underlying ideas are described in this book chapter:

Bracke MBM. Chains as proper enrichment for pigs (incl. supplement). In: Spinka M, editor. Advances in Pig Welfare: Elsevier (2017). The chapter (without supplement) can also be downloaded here.

Abstract

This chapter primarily compiles work in which the author (Marc Bracke) has been involved with providing science-based decision support on the question of what is proper enrichment material for intensively-farmed pigs as required by EC Directive 2001/93/EC. Proper manipulable material should primarily provide occupation (i.e. reduce boredom), and preferably reduce tail biting.

The RICHPIG model was built expressing enrichment value as a score on a scale from 0 to 10. Metal objects like short metal chains had the lowest score. Subsequently, the Dutch government banned the use of metal chains, and most Dutch pig farmers attached a hard plastic ball or pipe to the prevalent, short metal chain. Unfortunately, our on-farm observations repeatedly suggested that this ‘enrichment’ may have reduced pig welfare, rather than improving it as intended by the Directive.

So-called AMI (animal-material interaction) sensors can be used to (semi-)automatically record object manipulation by attaching a motion sensor to hanging objects. Exploratory data are presented to, directly and indirectly, record enrichment value. AMI-sensors may provide objective, flexible and feasible registration tools of enrichment value, but their application is still rather demanding.

That the enrichment value of short metal chains can be improved upon, e.g. by providing branched chains. Essentially, this entails making chains longer, preferably reaching until the floor, and making them more readily available in a pig pen. To facilitate the process towards proper enrichment the principle of intelligent natural design (IND) is proposed. IND entails organising a repeated selection process of the (currently) best-available enrichment material so as to gradually reduce pig boredom and enhance the opportunities for the rearing of pigs with intact tails. IND should start with basically all pig farmers implementing promising enrichment like the branched-chain design on their farms as soon as possible, followed by conducting small-scale on-farm experiments to compare and improve enrichment through sharing of available knowledge. Suggestions are given as to how and why this novel approach can be implemented to solve persistent animal-welfare problems like providing proper enrichment for intensively-farmed pigs.

Related posts:

Chains as enrichment for pigs (Book chapter with supplement)
Ketting als hokverrijking voor varkens (incl. link naar het supplement)
Pig animation – Improved, branched chain design as proper enrichment for pigs
Branched chains as enrichment for pigs (technical description, pictures and video)
Proper enrichment for intensively-farmed pigs – From review to preview
A collection of pictures of other enrichment materials for pigs can be found here: Prize contest (Prijsvraag) 2011.
Do pigs play with chains? Science versus society

The video below shows the value of a branched chain provided in the outdoor run of organic pigs. This prototype branched was called ‘enriched chain’ because it was having various branches and reaching till the floor. The prototype was not yet made of stainless steel anchor chain links, but of relatively large c-chain links (2.5 cm wide, 5.5 cm long). It also shows that pigs show signs of frustration when trying to manipulate the hockey-type ball hanging on a short chain.

Tool for scoring tail, ear and skin lesions in pigs

Deutscher Schweine Bonitur Schlüssel (Geman pig evaluation key, in English)

The ‘key’ provides a standardised classification for recording skin lesions.

In the course of numerous recent tail biting projects, German investigators developed a common tail and ear lesion scoring key in order to make results more comparable. The key now has a composite nature. Depending on the background of the study, lesions can be scored in different levels of detail which can be combined in order to allow analyses across projects. The provided documents include a summary key, descriptions of scores and exemplary pictures (follow this link for the document in English).

PS German guidelines for the on-farm assessment of farm animal welfare (cattle, pigs and poultry) can be found here (in German).