In January, a farmer called for help when he had a series of sudden deaths over a period of 3 weeks in his cows. From a total of 82 cows and calves, 7 died.
After a property visit, a possible lead source of batteries was identified and cattle were removed from this paddock. None were exhibiting any unusual behaviour or clinical signs.
Another animal died suddenly ten days later.
The cow was necropsied. Both eyes had hemopyon, but no discharges from nose or anus. Even though we are outside the typical Anthrax belt, a slide was taken for Anthrax rule out just in case. The liver was swollen and pale, kidneys were also pale and appeared to be fairly advanced decomposition for the time of death.
The most significant findings were the lead fragments found in the reticulum.
46 calves were blood tested for exposure and 8 of them returned high lead levels.
In the past 2 years the Young RLPB has seen a number of lead poisoning cases in both cattle and sheep. Lead fragments in the reticulum have been a consistent finding in cattle in at least 3 of these cases where batteries were known to be involved.
The fragments feel much like a large amount of sand or pebbles in the reticulum when palpated through the wall. When opened up, the reticulum will have multiple small fragments that make up a surprising volume of lead when all put together.
The picture below shows the total amount retrieved from the reticulum of this cow scooped out of the reticulum and put on the carcass nearby.
The fact that this cow had no clinical signs supports the theory that the action of the rumen can cause high lead levels released into the blood stream resulting in an 'acute' poisoning even though this animal had been removed from the lead source 10 days prior.