I myself remedied that problem, with a simple solution, others suggested to me. I put Lightningrods over grass patches, not individually, but surrounding a number of them; essentially, closing of grass "squares", inside fence-like constructs, but from Lightningrods!
From my 2 coops 2 barns filled to the brim with animals, only small areas of growing blue grass, is ever being chewed up. The real problem isn't the animals' apetite for me though, but the chance of normal grass to spawn and spread, since i always want to trim it... Which forces me to open holes in my meadowlands! Especially annoying, whenever normal grass, appears in the place that animals ate up the blue patches.