In finishing pigs, material and labour costs of added enrichment were compared to the estimated benefit from the observed decrease in tail biting. In breeder pigs, material and labour costs were compared to the percentage of pigs that were approved as breeders at half a year of age.

The economic results are only suggestive, because the research was carried out on just three farms. Other farms can have other combinations of factors affecting tail biting and related costs. Therefore, the same enrichment can have a somewhat different economic impact on different farms.

The cost of using enrichment objects made of fresh wood, which were found to be the best functioning objects in this project, was 1.80 Euros per each slaughtered pig. This includes both material and labour costs.

Based on these results, it seems that although the reduction in tail biting improves economic profitability, this improvement is not sufficient to fully cover the costs of enrichment. However, in some EU countries with the animal welfare payment system, the farmer can get the extra costs covered by applying for this payment. (For example in Finland, the design and quantity of wooden objects described on this website do fulfil the criteria of the payment.) This will bring economic profitability onto the same level as ordinary production without wooden objects and animal welfare payments.

The calculation of costs was based on the following assumptions:

- The length of wood is 20 cm / pig.
- The wooden pieces are replaced with fresh ones twice a year.
- The chains for suspending the wooden pieces are replaced once in five years.
- The wholesale price of chain is 1.20 Euros / metre (4 mm, long-link, hot-dip galvanized).
- The time needed for transporting the wood from the forest, sawing, drilling, attaching chains and suspending in a pen of ten pigs, is a total of 1 hour 40 minutes (based on time taken during the research project).
- The labour cost, including indireect costs, is 15 Euros / hour.

The labour cost for one ten-pig pen is 1.7 hours of work x 15 Euros/hour = 25.50 Euros, which is repeated twice a year. Total

labour cost per pen is 51.00 Euros / year = 5.10 Euros / pig space / year = 1.50 Euros / pig.

The material cost is 4 metres of chain = 4.80 Euros, which is needed once in five years. Total material cost is 0.96 Euros / year / pen = 0.10 Euros / pig space / year = 0.28 Euros / pig.

Therefore, the total cost is 5.20 Euros / pig space / year = 1.78 Euros / slaughtered pig.

The cost of using enrichment objects made of fresh wood, which were found to be the best functioning objects in this project, was 1.80 Euros per each slaughtered pig. This includes both material and labour costs.

The tested new enrichment system yielded the same percantage of approved breeder gilts as the system normally used on the farm, and the need for medication was also the same in both. Material and labour costs for enrichment were approximately the same in both arrangements. Both systems also made the farm eligible for animal welfare payments. The observed improvements in pig welfare in the new system therefore came at no financial cost.

The calculation of costs was based on the following assumptions:

- The commercial chewing sticks are replaced with new ones twice a year (according to experience of workers on this farm). Their wholesale price is 1.80 Euros per piece. This totals 8 sticks per year costing 14.40 Euros / 10 piglets = 1.44 Euros / piglet.
- The wholesale price of polyethene pipe (with a diameter of 25 mm) is 0.58 Euros / metre.
- The time needed for sawing the polyethene pipes, attaching chains and suspending the objects in a pen of ten piglets is 17 minutes (based on time taken during the research project).
- Assumptions on wood use are the same as in finishing pigs, see on the left.

Costs of the new system, from weaning to selection of breeder gilts at half a year of age,: For polyethene pipes, the labour cost for one ten-pig pen is 0.28 hours of work x 15 Euros / hour = 4.25 Euros, and the material cost is 1.16 Euros. This totals 5.41 Euros / 10 piglets = 0.54 Euros / piglet. For wooden pieces, the cost is 1.80 Euros per pig, as with finishing pigs (see the calculations on the left). Total costs are 2.34 Euros / pig. However, results from the finishing pigs' experiment number 2 suggested that the object made of polyethene pipes can be replaced with an equally efficient model in which only 100 cm of pipe per pen is needed. Replacing the plastic objects for weaned pigs with this version would reduce the total costs of the new system to 2.07 Euros / pig.

Costs of the ordinary enrichment system on the farm: The amount of wood and chain use is approximately a third of that in the new system. So the material and labout costs can be estimated as a third, i.e. 0.60 Euros per pig. The commercial chewing sticks cost 1.44 Euros / piglet. The total cost of the ordinary system of enrichment on this farm is 2.04 Euros / pig.

The tested new system of enrichment for breeder pigs, based on the use of fresh wood and replacing commercial chewing sticks with polyethene pipes, carried no extra cost as compared to the ordinary system of enrichment on that farm.

There has not yet been enough research on how enrichment in the farrowing pen affects tail biting later in life. Therefore it s not yet possible to make exact calculations on economic benefits of farrowing-pen enrichment. However, this system of enrichment does fulfil the criteria of animal welfare payments in at least some EU countries (including Finland). This enables the farmer to get the costs covered that way.

The calculation of costs was based on the following assumptions:

- The total length of rope is 7 metres / pen.
- The ropes are replaced with new ones after each litter.
- The wholesale price of sisal rope (with a diameter of 10 mm) is 0.33 Euros / metre.
- The time needed for cutting and attaching the ropes in one pen is 14 minutes (based on time taken during the research project).
- The labour cost, including indireect costs, is 15 Euros / hour.

The labour cost is 0.23 hours / litter x 15 Euros / hur = 3.5 Euros / litter.

The material cost is 2.13 Euros / litter.

The total cost is 5.63 Euros / litter.

If there are 12 litters per year in a pen, the cost is 12 x 5.63 Euros = 67.56 Euros / litter space / year.

If the number of piglets weaned per litter is assumed to be 11, the total cost is 0.51 Euros / piglet.

The cost of using sisal ropes, in the way they were tested in this project, was 0.50 Euros per each piglet. This includes both material and labour costs.