And now, a reply that might actually be helpful, possibly [raspberries to you two guys]: I think you were right, Marianna, and that the recipe was probably copied wrong. Look at this one, for ex.:
Title: Escabeche De Gallina (Marinated Chicken)
Categories: Chile, Meat dish
Yield: 4 Servings

1 c Celery leaves
1/3 c Vinegar, wine
2 ea Parsley sprigs
1 t Salt
2 ea Cloves, whole
1 c Water, hot
1/4 t Thyme, dried
2 ea Onions - cut in rings
1/3 c Olive oil
1 ea Carrot - sliced
2 1/2 lb Chicken pieces
1 ea Leek - sliced
1 c Wine, white, dry
1 ea Lemon - cut in 8 wedges


This one has ea where I'd expect to see it, though it strikes me as odd to put "each" when you only need one of an item. Perhaps it's one of the cultural differences in recipe-writing?

Edit: but maybe it was a pretend recipe. You'd need a LOT more than 3 and 1/3 cups of liquid to go with 600 filets of anything.