The upside of a few dead animals…
There are a variety of conditions that cause poor performance in our flocks, some are treatable, some are not.
A common practise on many farms is to drench tail end ewes, however in many cases parasitism is not the issue. A simple post-mortem of a few tail end ewes, either poor ones or those destined for the dog tucker freezer can yield some very useful information. As with many aspects of sheep farming, it’s not about the individual animal, it’s about identifying trends that can help with future farm management.
Your vet will no doubt be able to help you with some post-mortem tips and identifying different conditions. The most important thing is to have a systematic approach so that things are not missed. Always lie the sheep left side down as this makes the intestines easier to examine. When examining organs, have a look externally as well as slicing them open. With the advancement of technology, it’s now very easy to take some pictures and send them off for a second opinion. It’s a good idea to take photos of how the animal looks when you open it up, including the entire carcass, as well as photos of individual areas of interest. Sometimes it is hard to make a diagnosis on one piece of liver, so take a few different views of different organs, even if it doesn’t seem important or interesting.
COMMON CAUSES OF ILL-THRIFT
Dental issues – either lack of incisor teeth, or issues with the molars – make sure you open the side of the face to look at these teeth.
Pneumonia and pleurisy – these are common issues in both ewes and lambs. Pleurisy refers to the lungs being stuck to the chest, while pneumonia is inflammation of the lung tissue – it often appears very dense and like liver
Liver disease – most commonly facial eczema which results in a smaller stunted liver with rounded edges. Make sure you open the bile ducts and give the liver a squeeze to look for liver fluke.
Bowel Cancer – this is common in older ewes and appears like mottled patches on the small intestines
Johnes – common in sheep, there is one area to look for this, where the large and small bowel join. It causes very distinctive thickening in this area.
Many of these conditions are irreversible and after a while you may notice a trend with one age group or another and this may allow you to make decisions about these ewes earlier. A common example would be an age group that was pinched as hoggets due to drought, this group will often be over-represented as an ill-thrifty group over time.
While death and poor performance is frustrating it can be used to understand current issues with the aim to minimise them in the future. Most vets love dealing with dead things, so will be happy to assist you with your post-mortems or visit your farm and do a few for you.