I hope the LA200 works for you. I have dealt with two abortion storm: one probably eight or nine years ago, and a worse one this year. Both times Aureomycin and tetracycline were ineffective in stopping losses. The first one, lab results showed it was a strain of Campylobacter jejuni that was resistant to tetracyclines and sulfa. Nuflor salvaged that lambing season. This year the lab was unable to isolate a cause. Aureomycin had no effect. If the Nuflor worked, it was temporary. A ewe would abort every threw weeks, almost like clockwork. I finally vaccinated every ewe that was still bred for Chlamydia, Vibrio and lepto. Whether it just ran its course or the vaccines were effective, I don't know, but I have had no more problems. Needless to say, it has been a rough year. I hope yours progresses better than mine. If you have any more problems, I would vaccinate.