Keep up us updated... To me looks like grass tetany or listerisosis. Either way, it is call the vet time!!! You always want to be extra cautious about neurological problems as rabies is always on the list of things to be ruled out. Just saying this because that is first thing our vet drilled into my head many, many years ago when trying to figure out what is wrong.
Often temp won't be elevated at first with listeriosis. Understand that it too is communicable to humans, so latex gloves and wash hands. But, usually they are more likely to head press, circle, etc... rather than tremoring like ram is doing.
Polio you would see more head pressing, neck arched back, etc...
If this were a calf/cow I would say absolutely it is grass tetany. There is a unique sugar in new, flush growing grass that ties up magnesium and causes the tremors. I always fed a mineral mix with magnesium in it and an even higher dose of magnesium in spring. Once grass is over ankle high the sugar is decreased and doesn't present a problem. Seen some of it in cattle, and sad to say, no matter treatment, once down they did not recover. In very, very mild cases giving magnesium did help, but not once they were down and spasming.
Poisoning on a plant? Could be. Had a goat get into the tobacco barn after we had hung green tobacco to cure and she had spasms, tremors, could not stand, cried in pain, but with a reduced body temperature of 95 F..... fast trip to UT Vet school and correct diagnosis saved her. Passing a large dog esophogeal tube in order to give about two quarts of liquid activated charcoal stopped her symptoms in a matter of minutes. That was Simple Life Kasey and I put her in the backseat of my Corolla to get her to and from UT.
