A weekend in Switzerland
The Swiss Sheep Society (Schweizerischer Schafzuchtverband or SSZV) have just introduced an ultrasound machine for the first time, supplied by Vet Image Solutions in Bromley. Using a linear probe, they will begin collecting data on fat and muscle depth in sheep across Switzerland.
I visited the society on Saturday, and we spent the day going through the controls of their new system – particularly the importance of frequency, depth, gain and focal point. Optimising image resolution is particularly important for meat grading work, where measurement accuracy is so important (you can read a more in depth article on this topic here: sheep muscle depth with ultrasound).
It is easier to scan unshorn sheep, as their wool can be easily parted with a stick. Liquid paraffin or gel can then be applied directly to the skin.
Scanning between the last ribs, it is then possible to obtain an image which is effectively a representation of a lamb chop onscreen. From this image, the operators measure the total depth from the beginning of the fat layer down to the bone, muscle depth, and then fat depth. The fat depth is taken at three points along the length, because in some sheep, the depth of the fat layer is not uniform.
The society also bought a large convex probe for pregnancy scanning.
Below are a few clips from their first few scans. In one, it is possible to see a twin pregnancy:
After a day with the Swiss Sheep Society on a farm in Gretzenbach, I spent Sunday catching up with Heinz Plüss, who first introduced ultrasound for meat grading in Texels five years ago. Accompanied by Kathrin Bühler (agricultural tour guide and herself a sheep expert) and her husband Fritz, we went to a sheep show, followed by lunch at the Mossegg Hotel with the most beautiful views.
It was interesting to learn about the unique problems that Swiss sheep farmers are facing. In the last decade, brown bears have been reintroduced into Switzerland, and since the signing of the Bern Convention in 1979, the wolf and lynx populations have also grown. Many see the romanticism of protecting these carnivores as incompatible with farming sheep; as sad as it is, these predators were killed to the verge of extinction for a reason. The traditional Swiss way of farming involves sending the sheep up into the Alps for the summer, only bringing them back in autumn as the cold weather approaches and grazing land becomes scarce. Now, farmers are sending their sheep up in spring, and fewer are coming home.
Wolves seem to be particularly destructive. The lynx will kill a sheep quickly, and will eat all of it (hiding and returning to the carcass several times). Wolves, however, will kill and maim multiple animals, often ripping their flesh open and leaving them in agony for hours or days. Rather than kill an animal quickly and efficiently like the lynx, they will happily eat a sheep alive.
There seems to be no perfect solution to this current problem. Limiting the freedom of movement of these sheep destroys an entire tradition, not to mention the changes it would bring to the landscape, with areas eventually becoming overgrown and less accessible to hikers or picturesque for tourists. Putting up fences all over the mountains would have the same effect. Some farmers now send dogs up with their flocks for the summer, but again, this causes a problem for hikers who no longer have freedom to roam when flocks are protected by guard dogs. The dogs also need feeding – they are not largely self-sufficient like the sheep – and and then there’s the problem of what to do with them in the winter. As Kathrin pointed out to me, the dogs cannot be bonded too closely with their humans, because their job is to see their family as the sheep, and protect them. As such, they need to be boarded with the sheep during winter.
Below, the jingling bells of a sheep at a show in Switzerland. The sheep wear these bells so that they can be found by the shepherd in difficult terrain or bad weather:
April 09, 2020
January 21, 2020