Welfare indicators
Dossier: Group-housing and mixing of sows
Animal-based indicators to monitor sow’s welfare related to group-housing and mixing.
The sow’s physiological and behavioural needs are described under “Knowledge”. Based on these needs, four areas regarding welfare of group-housing and mixing are identified. For these key areas, indicators are suggested to facilitate welfare inspections on-farm:
- Mixing of unfamiliar animals
- Competition for resources
- Restrictive feeding
- Climatic and resting comfort
An overview of indicator factsheets for this topic can be found on the "Indicator factsheets" webpage.
Mixing of unfamiliar animals
Indicators to assess the effects of mixing:
- Skin lesions: Lesions include broken skin, fresh (i.e. bleeding) wounds and healing lesions. Skin lesions can result from aggression related to establishing a social relationship with unfamiliar sows and/or competition for resources (feed, water, lying space).
- Lameness: When lame, a pig is unable to use one or more limbs in a normal manner. Lame pigs experience pain and discomfort. Causes: agonistic interactions on slippery floors, but also prolonged lying duration on hard floors.
Relevant links
- Skin lesions: indicator for aggression due to mixing of, or competition between, sows, indicator factsheet EURCAW-Pigs, [in prep.]
- Lameness: indicator of sows’ pain and discomfort due to insufficient flooring, indicator factsheet EURCAW-Pigs
- Effects of group housing on sow welfare: a review, Verdon et al, Journal of Animal Science, 93(5), pp. 1999-2017, 2015
- Group housing of sows in early pregnancy: A review of success and risk factors, Spoolder et al., Livestock Science, 125(1), pp. 1-14, 2009
- Welfare of dry sows, Marchant-Forde, In ‘The welfare of pigs (pp. 95-140)’, 2009
The accumulation of skin lesions and their use as a predictor of individual aggressiveness in pigs, Turner et al., Applied Animal Behaviour Science, 96, pp. 245-259, 2006
Competition for resources
Indicators related to competition for resources are:
- Skin lesions: Lesions include broken skin, fresh (i.e. bleeding) wounds and healing lesions. Skin lesions can result from aggression related to competition for feed, water, or lying space and/or establishing a social relationship with unfamiliar sows.
- Body condition: The assessment of body condition indicates whether individual sows have obtained sufficient food.
Read more & relevant links
- Vulva lesions: Damage to the vulva may indicate competition for food when sows are feeding in stalls and are being approached from behind by a competitor/biting and competition in feeding stalls if sows can enter other sows stalls.
- Manure on the body: Sows may be dirty from manure on the body due to e.g. lack of (lying) space, thermal stress or bad ventilation.
Relevant links
- Skin lesions: indicator for aggression due to mixing of, or competition between, sows, indicator factsheet EURCAW-Pigs
- Body condition: indicator of quantity of food intake by individual sows, indicator factsheet EURCAW-Pigs
- Vulva lesions: indicator of being bitten by a competitor when sows are feeding in stalls without protection, indicator factsheet EURCAW-Pigs
- Manure on the body: indicator for sows’ competition for lying areas and climatic comfort, indicator factsheet EURCAW-Pigs
- Group housing of sows in early pregnancy: A review of success and risk factors, Spoolder et al., Livestock Science, 125(1), pp. 1-14, 2009
- Welfare of dry sows, Marchant-Forde, In ‘The welfare of pigs (pp. 95-140)’, 2009
- The accumulation of skin lesions and their use as a predictor of individual aggressiveness in pigs, Turner et al., Applied Animal Behaviour Science, 96, pp. 245-259, 2006
Restrictive feeding
Indicators related to restrictive feeding are:
- Stereotypies: behavioural patterns performed repetitively in a fixed order and without any apparent function (e.g. sham chewing, tongue rolling, bar biting). They may be a sign of frustration due to hunger and inappropriate foraging behaviour.
Relevant links
- Stereotypies: indicators for frustration due to hunger and inappropriate foraging behaviour in sows, indicator factsheet EURCAW-Pigs
- Mitigating hunger in pregnant sows, D'Eath et al., In: ‘Advances in Pig Welfare’, pp. 199-234, 2018
- Effect of dietary fibre on the behaviour and health of the restricted fed sow, Meunier-Salaün et al., Animal Feed Science and Technology, 90(1), pp. 53-69, 2001
- Influences of feeding level and physical restriction on development of stereotypies in sows, Terlouw et al., Animal Behaviour, 42(6), pp. 981-991, 1991
- Stereotypies, aggression and the feeding schedules of tethered sows, Rushen, Applied Animal Behaviour Science, 14(2), pp. 137-147, 1985
- The effect of straw on the behaviour of sows in tether stalls, Fraser, Animal Science, 21(1), pp. 59-68, 1975
Climatic and resting comfort
Indicators for climatic and resting comfort include:
- Panting: Sows try to lose heat by high-frequent, open-mouth breathing.
- Manure on the body: Sows may be dirty from manure on the body due to e.g. lack of (lying) space, thermal stress or bad ventilation.
- Lameness: When lame, a pig is unable to use one or more limbs in a normal manner. Lame pigs experience pain and discomfort. Causes: prolonged lying duration on hard floors, but also aggressive interactions on slippery floors.
Relevant links
- Panting: indicator of heat stress in sows, indicator factsheet EURCAW-Pigs
- Manure on the body: indicator for sows’ competition for lying areas and climatic comfort, indicator factsheet EURCAW-Pigs
- Lameness: indicator of sows’ pain and discomfort due to insufficient flooring, indicator factsheet EURCAW-Pigs
- Field evaluation of a water-cooled cover for cooling sows in hot and humid climates, Pang et al., Biosystems Engineering, 110(4), pp. 413-420, 2011
- Review of wallowing in pigs: Description of the behaviour and its motivational basis, Bracke, Applied Animal Behaviour Science, 132, pp. 1-13, 2011
- Thermal behaviour of growing pigs in response to high temperature and humidity, Huynh et al., Applied Animal Behaviour Science, 91(1), pp. 1-16, 2005
- A cross-sectional study of the prevalence of lameness in finishing pigs, gilts and pregnant sows and associations with limb lesions and floor types on commercial farms in England, KilBride et al., Animal Welfare, 18(3), pp. 215-224, 2009
- Effect of slatted floor area on ammonia emission and on the excretory and lying behaviour of growing pigs, Aarnink et al., Journal of Agricultural Engineering Research, 64(4), pp. 299-310, 1996
- Evaporative cooling in the pig, Ingram, Nature, 207(4995), pp. 415-416, 1965