Poisoning from eating unripe acorns

Summer isn't even over yet, but you have to watch out for unripe, green acorns and oak leaf.
These are toxic to animals.

Because of climate changes, acorns are falling earlier and earlier, especially during storms or strong gusts of wind.
Animals such as sheep, goats, horses and cattle like to eat them, without knowing how toxic they are to them. Horses and cattle mainly eat acorns when the supply of grass or other nutrients is limited. But dogs also eat acorns from time to time. Try to avoid this at all times; acorns are not only very harmful to dogs, the sharp spots can also cause internal damage.

Acorn poisoning is caused by the substance tannin, which is found in both the acorns and the oak leaf. The younger the leaves and acorn are, the higher the concentration of tannin. Tannin is converted by the body into toxic substances and damages the inside of the blood vessels, kidneys and intestines. In the intestines tannin will bind to protein and iron, causing a shortage of these substances. The intestinal mucosa contracts resulting in kidney damage.

In the least serious case, the animal will suffer from digestive disturbances. Clogging and bloody diarrhoea are associated symptoms. 

Symptoms of disease in cattle

The first symptom is slowness. The animal isolates itself from the flock and does not eat sufficiently, probably caused by the lowered body temperature. Other possible visible signs are: accelerated breathing, bloody nasal discharge, abdominal pain and bloody diarrhoea.

Symptoms of disease in horses

The tannin affects the gastrointestinal wall, causing ulcers, gastrointestinal blockages and anaemia.
The horse has a reduced appetite, colic symptoms and dark coloured urine. If brushing is sensitive in the abdominal area, this may indicate acorn poisoning.

Symptoms of disease in sheep

Sheep are very susceptible to acorn poisoning.
They become restless, have a reduced appetite, suffer from constipation, colic symptoms, bloody diarrhoea or get a swollen stomach.
They sometimes have a stiff gait, after which paralysis symptoms can occur. Sheep then drink and urinate a lot.

It is best not to place the animals in a field where a lot of acorns are present. Make sure that animals have sufficient access to other nutrients such as a licking block or concentrate. Temporary fencing or moving animals to another plot can also be a good solution.
If in doubt, always contact your veterinarian.