With this online Lameness Scoring training course we aim to give you a better understanding of the problem of lameness in sows. Above all we hope to teach you to recognize various stages of lameness so that you can spot lameness, assess its severity, and intervene in time. If, after completing the training course and scoring the sows on your farm, you notice that their movement could be improved, be sure to discuss this with your farm veterinarian and possibly other advisors. It's worth talking about because prevention really does pay of!

What is lameness? 

Lameness is the main clinical symptom of movement problems. It is characterized by abnormalities in the animal's normal stride pattern and general posture and by decreased mobility due to pain and/or discomfort. The underlying causes are often leg and claw injuries, as well as certain diseases (e.g. arthritis). Lameness not only undermines animal welfare, but also causes significant financial losses for the pig farmer. Since treatments of advanced lameness are not always effective, prevention and early detection of lameness is extremely important.

What are the risk factors regarding lameness in sows? 

Lameness is frequently seen in sows in group housing. It is important to remember that lameness is a multifactorial condition in which multiple risk factors may play a role. Sow management, breed choice, floor type, and nutrition, among others, can play a role in its occurrence. 

Often, leg and claw injuries lead to lameness. Claw injuries are also an ideal entry route for bacteria, after which they can cause infections at the claw but also higher up in the leg. Housing, especially the flooring, is one of the main risk factors. Both the type of floor and hygiene play an important role. Non- or partially covered concrete grids are a frequent cause of claw problems. In addition, moist, dirty floors, sharp protrusions, litter that is not changed often enough and too little attention to the sows' leg work are common problems. 

It is also increasingly thought that nutrition may play a role in preventing lameness. This is because certain nutrients are essential for avoiding claw injuries. These nutrients are fatty acids, amino acids (methionine and cystine), minerals (calcium, zinc, copper, manganese, selenium and chromium), vitamins (A, D, E) and biotin. 

What is the impact and cost of lameness?

In addition to the negative effects on sow welfare, lameness also comes at a financial cost. The actual cost depends on the severity of the lameness, but can range from €22 to as much as €138 per lame sow. When treatment is an option, the medication and extra work hours are obviously an additional cost for the pig farmer. In addition, research has shown that lame sows give birth to more stillborn piglets than non-lame sows, and that crushing of piglets in the farrowing pen is more frequent because lame sows have a hard time changing position. Lameness is also one of the most common reasons for sending a sow to the slaughterhouse. Slaughtering a sow at young age due to lameness leads to a smaller number of litters and therefore fewer weaned piglets on the farm. In addition, these sows will often yield less at the slaughterhouse, as claw problems often result in other infections. In addition to premature removal of lame sows to the slaughterhouse, sows with severe lameness should be euthanized immediately.

How to score lameness and the importance of prevention

Early detection of lameness is of the utmost importance. Lameness in sows is mainly assessed visually, using a scale. However, since the severity of lameness can vary greatly, it is sometimes difficult to determine at what point a sow should be considered lame. Therefore, it is more interesting to score lameness using a continuous scale instead of working exclusively with "lameness categories". This online course shows you how to use this type of continuous scale in practice (also called "visual analog scale" or VAS) supplemented with some indications or tags (tVAS) (Nalon et al., 2014). Scoring with this continuous tVAS scale is no less reliable and takes about the same amount of time as a categorical scale (Nalon et al., 2014). A mark is placed on the scale (see below) which is then measured (e.g., 45/150) to express the severity of the lameness. For easy scoring in the barn, print this score sheet and take it with you. 

You can learn to score lameness by watching these 30-second instructional videos of sows at the various stages of lameness (Step 1: teaching material). Afterwards you will watch 8 videos (Step 2: practice videos) and assign a score to the sows yourself. After each training video you will receive feedback so that you know to what extent your score corresponds to that of the experts.

Course materials

The course material below shows what to look for when using the tVAS scale to score lameness in sows. For each lameness category you can watch one or more videos. At the end of each video we explain what can be observed. This includes the suppleness of the movements, equal or unequal strides, any stiffness, any lameness, whether the sow needs encouragement to walk, and whether compensatory movement is being exhibited. Afterwards you can go through one or more practice sessions (see below step 2: practice videos) to master this scoring method yourself.

 

Try your hand at scoring videos

To practice scoring lameness with the tVAS scale, you can go through one or more of the sessions/videos below. Each session consists of short videos of 5 sows, which you can score one by one using the corresponding score bar (to the right of each video) and visual presentation of the tVAS scale (see above). Each session takes about 5 minutes. After completing the session, you will see the accompanying model solution. For each sow, a guideline score on the tVAS scale is given (average score based on that of experts), together with the corresponding category and what exactly can be observed. A total of 8 practice sessions are available.

Video 1

Video 2

Video 3

Video 4