In modern pig production, the herd managers send around 50% of sows for slaughter every year. In Denmark, this concerns approximately 500,000 sows a year. Before loading the so-called cull sows on the truck and transporting them to the slaughterhouse, it is the driver’s responsibility to decide whether the animals are fit for transport. Certainly, cull sows may show signs of various weaknesses or disabilities thus being harder to assess than younger, healthier animals.

In collaboration with Danish Technological Institute/DMRI, researchers at Department of Animal Science, Aarhus University, have conducted a questionnaire survey among all drivers transporting cull sows to a large Danish slaughterhouse. The purpose of the survey is to provide new knowledge about the drivers’ experiences and opinions. The survey is part of the research project SOTRANS, aiming at improving sow welfare during transport to the slaughterhouse.

Questionnaire survey directed towards drivers transporting sows

“We have chosen to include the drivers in the SOTRANS project, as they represent a professional group of people important to animal welfare and who take great responsibility in practice, but who are also assigned great legislative responsibility. At the same time, they form a group who we know very little about. Therefore, we are happy that many have supported our research and have been willing to participate in the survey”, says senior researcher Mette S. Herskin, Department of Animal Science, Aarhus University.

The questionnaire survey included answers from 22 drivers (out of 30 possible). After advance information, the drivers were interviewed at the slaughterhouse area immediately after unloading sows. The drivers were all men of varying age and with varying levels of experience – for example relative to the time since they achieved their certificate of competence.

Examples of questions raised in the survey are:

1.      How often do you reject sows selected for slaughter by a herd manager and for which reasons?

2.      What do you do when in doubt about fitness for transport?

3.      How often do you use special condition transport to safeguard the animals?

4.      How often have you experienced that the inspecting veterinarian at the slaughterhouse has rejected a sow based on lack of fitness for transport? What was the problem the last time it happened?

5.      How can weather conditions affect sow welfare during transport to the slaughterhouse?

6.      Do the driving and resting rules affect sow welfare during transport?

Results from the survey

Many experience fitness for transport as a concept without a clear definition. At the same time, neither Danish nor EU regulation in this area are clear. Primarily, certain clinical conditions are listed, as leading to animals not being fit for transport. In the survey, it was not uncommon among the drivers to be in doubt about fitness for transport. They talked about challenges with grey zones, but, for example, some also answered: “When I am in doubt, the sow is not loaded”. At the same time, the answers showed that the use of special condition transport varied a lot among the drivers. All drivers from the survey had tried to reject loading and transporting a sow who had been selevted for slaughter by a herd manager; 40% experienced this several times a year. Typical reasons for rejection of sows were leg problems and shoulder ulcers. On the other hand, almost 50% of the drivers answered that they had never had a sow rejected due to lack of fitness for transport by the responsible veterinarian upon arrival at the slaughterhouse.

Management during transport

All participating drivers considered hot days a problem for welfare of sows. Moreover, almost half the drivers mentioned stationary periods (for example breaks during driving in order to meet the driver’s driving and resting rules) as a challenge for the sows’ welfare – even to such an extent that several had violated these to safeguard the sows.

The survey does not include large-scale data. However, the data show clear trends among the drivers of for instance doubt about fitness for transport; that they reject sows in the herd; that the use of special condition transport varies a lot but also that the drivers were aware of several of the known risk factors for pigs’ welfare during transport, for example high temperatures.

“The results of the survey suggest several areas in which future research  and development is necessary to ensure animals’ welfare during transport – for instance when the temperature in the truck is high or when the truck is stationary (resulting in rising temperatures). We will look further into these aspects in the next phases of the project and pay attention to the positive fact that the drivers are aware of it. The results about fitness for transport confirm that this concept is not always easy to work with”, concludes Mette S. Herskin.

Facts about the project