I need to dose my hens with Tetracycline, but the bag says "Not to be used in Laying Birds or Lactating Cows" For those of you who have used Tetracycline, is this because of withdrawel times? If I put it in their water will it hurt them? I'd be throwing out my eggs probably for 2 weeks. We've got a good store up so we should be fine in that time period. Thoughts?