Had quite a go of it lately. Just got back from Mexico on the 23rd to have heifers dying in the pen at the rate of at least one a day. No stomach troubles (no bloating or discomfort), no coughing, just go out in the morning and there's a dead calf or two in the pen. And of course over Christmas the vets aren't all that helpful. I finally got to talk to the large animal vet on friday, and he said to have a look at the heart and lungs of a recently deceased calf and see if they appeared normal. Well, instead of nice light pink lungs, they were quite dark. He then told me to run them all through and give them 30cc of oxytetracycline. That's alot of medicine, especially when everything is closed on boxing day. Luckily a neighbour had a case of it and we ran them through. So.... now that we're 10 head short we are much smarter. I think. I can still hardly believe how fast this infection could take a healthy appearing calf and kill it stone dead.