My daughter owns 3 rescue boxers and yesterday she was walking them in my fields quite normally, they were just sniffing around 'doing what dogs do'.
She returned home to my house and suddenly one of the boxers dropped to the ground, on her side legs kicking etc in a kind of fit, although it only lasted about 20 seconds. While we were running to help her one of the other boxers dropped to the ground and did exactly the same 'fitting' as well, again only for around 20 seconds. Both seemed quiet but fine afterwards.
We phoned the vet and he couldn't understand how 2 dogs could have the same reaction, one could be understandable but not 2. He also said that the day before he had a call from another owner with a dog that experienced the same type of unexpected reaction as our dogs, so he is baffled. We have got to take in urine samples for testing, but it is a matter of keeping an eye on them.
We have searched the field but cannot find anything out of the ordinary that could have caused this. (Vet asked if we had any magic mushrooms, if so could he have some !!)
Anyone got any ideas?

I'm not big on coincidences.

Sounds like the field may have been sprayed with a pesticide based on a formula which is basically a nerve toxin.

This happened on the Isle of Wight and several people got together to sue the farmer who crop sprayed right up to their garden edge.Many pets were affected including pond fish.

That is a possibility as even though the land is mine it is bordered by farmland and I know they have been doing things to the farmland ( it smells rotton) where the dogs were mooching was up against the boundary hedgerow, so they may have been spraying. Thanks for the idea I hadn't even considered this as a possibility.

That was the first thought that crossed my mind. Hope it never happens again and the Boxers are ok