We have seen as a practice that this pattern is changing. We are now seeing a lot of cases during the winter, and they are not always associated with high mortality or large production drops. It also seems to be affecting birds of any age. When we diagnose the disease on different farms, we are also noticing that there is no obvious link between them.
This changing pattern highlights the importance of doing postmortems on any dead birds to ensure that the disease is not present.
It has also been reported in caged birds and broilers, as well so please bear this in mind if you suspect spotty liver.
Diagnosis is achieved by postmortem where characteristic lesions are visible on the liver. The liver appears to be covered in small grey-white lesions, 1-2mm in size. Further testing in labs shows that these lesions represent a multifocal hepatic necrosis.
These areas of the liver that are irreversibly damaged.
Some of the risk factors identified by the research include the following:
- Damaged gut by worms or cocci, link via the portal vein (vein leading from gut to the liver itself)
- Excess surface water close to the house leading to faecal oral spread.
- Mycotoxins in feed. (Inclusion of a binder may be useful)
- Shared grazing with ruminants.
- Possible earth worm involvement, they have potential to act as transport hosts to the Campylobacter.
- Higher than average ambient temperatures.
The bacteria Campylobacter is a bacteria which commonly affects the gut. A novel Campylobacter has been identified as a cause of spotty liver. The bacteria is thought to spread between the birds via faeces which other birds then ingest.
As you can see from the risk factors, maintaining good gut health is an essential tool to prevent the infection. As ever, excellent biosecurity is a must as well as keeping the birds environment as clean and dry as possible. We have also found that the inclusion of products that promote gut health via the feed or water can help prevent or aid recovery from Spotty Liver infection.
Treatment for spotty liver does help reduce mortality and regain egg production in our experience.
If you have a flock affected by spotty
liver, please ensure you maintain strict
biosecurity between any other flocks.
If possible, avoid visiting your
youngest birds if you have another
flock affected, to avoid the risk
of spread.