Wednesday, 7 November 2012

Estimating and measuring animal welfare

Research in animal welfare is based on the assumption that animals have needs and intresses, which must be respected. Animal and its needs have intrinsic value. Research is focused on how the animal feels and adapts to its environment - what we think is best for the animal isn't what counts, but what the animal itself wants.

Why should we research animal welfare? Today, humans subject animals to heavy stress in unnatural environments. Contrary to what marketing wants us to think, agriculture is industrial and harsh. Animals are kept in herds/packs of tens of thousands, they are bred to grow fast and produce much. The relationship between consumers and farm animals has changed - it's common to over- or underestimate the mental abilities of animals, either treating them as machines or as humans. Laws govern much of agriculture, but the laws must be based on knowledge about animal welfare. Ethical reasons for animal welfare research are obvious, but a well-kept animal also produces more, gives higher quality products and  needs less costly vet services.

Measuring animal welfare

Measuring animal welfare is based on deep knowledge on what is normal for a healthy animal in it's natural surroundings. Any changes to its natural activities may indicate a problem with welfare. Thus the behaviour of an animal presents many "measurements":
  • Time budget: how much time does the animal spend eating, foraging, sleeping etc per day? Welfare may be decreased if the animal no longer sleeps well or doesn't rest as much as it used to.
  • Postures: Pain and confined spaces may cause animals to change their normal postures or movements. Long-term physiological problems may arise if normal movement is not possible.
  • Abnormal behaviour: disruptive or stereotypical behaviour indicates clearly that the animal is not well. It may be stressed, bored or has some other difficulty adapting to its environment.
  • Fighting: Naturally animal packs are rather calm, fights are normal only on mating time. In farms animals cannot form natural packs, which may lead to extensive fighting between animals.
  • Preferences of the animal
Before the measurements listed above can be considered, one needs to know what is normal. For example, pigs with litter and stimuli in their pen spend 1 % in harmful social behaviour, while pigs without litter fought each others nearly 10 % of their time. Pigs with litter also nose the ground almost 30 % if their time, 25 % more than pigs without litter.

Overall, there are two types of methods to estimate animal welfare: resource-based (input) methods and animal-based methods.

Resource-based methods
Even when given plenty of space,
calves prefer to stay close to one another.

Resource-based methods measure the environment of the animal, estimating the risk to bad welfare. Size of a pen, quality of feed, number of sick animals and air quality are examples of resource-based measures. Each target is easy to score, and the measurements are repeatable and clearly measurable. A well-known resource-based method is ANI, or the Animal Needs Index by H. Bartussek. ANI is divided into five categories, which all have several measurable objects. The categories are
  1. Locomotion (freedom of movement)
  2. Social Interaction
  3. Flooring
  4. Light and air
  5. Stockmanship
The farm receives points in each of these categories depending on the results. The sum of the scores in all categories is the ANI-index, ranging between -9 and 45.5 in the ANI for cattle. The higher the score, the better the welfare. Details of ANI for cattle can be found from Bartussek's homepage.

Animal-based methods
Animal-based methods focus on the animal, not it's environment. Measurements in animal-based methods are difficult and non-repeatable, since the results are affected by every factor in the animal's environment (temperature, time, hunger, people in the farm, noises...). They provide information of the animal on the time of the study. One animal-based method is the Welfare Quality®, created in an EU-funded poject in 2004-2009. WQ evaluation takes up to 4-7 hours, during which the farm is estimated in 12 criteria in four principles: Good feeding, good housing, good health and appropriate behaviour.


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