My now 12 week old yellow lab started having these episodes where his legs tense up, sometimes he can walk but is very clumsy, usually he lies down on his belly, he's shaky and can't stand up. This always happens either right before or right after meals. He will literally crawl spasmodically to his food and start eating during this. I can see his body relax, he'll stand up, finish eating and then he's fine. During the times it has happened after a meal it lasts 1-2 minutes and then is fine. He never loses conciousness - is completely alert through whole thing. We started feeding him every four hours and saw some improvement but still happening. Vet has done fasting blood sugar - normal; waiting for results of further testing, but nothing really fits. Has anyone else seen anything like this?