One thing most dairy farmers would agree with is that dairy farming is always interesting. There are always new opportunities and new challenges. Sometimes those challenges are mysteries.
I would call our latest mystery something like the The Case of the Cows Who Couldn't Stop Pooping. For about two weeks, every cow in the barn kept going and going and going.
When the diarrhea started, Glen's first thought was that we had a case of winter dysentery going through the barn. But, it just didn't seem like winter dysentery. In our past experiences with winter dysentery, the diarrhea started with a few cows, usually those in their first lactation, and then maybe a few others would get it - not the whole barn. And, the diarrhea wasn't foul smelling and watery.
So then, Glen questioned our forages, thinking there must have been an abrupt change in feed in one of the bags. He sent forage samples in the next morning. The results came back with only small changes in the forages.
Glen talked with our nutritionist about the issue. They hypothesized that with the extremely cold weather we had been having, our TMR wasn't mixing properly and we were ending up with a final mix that had too many small pieces. But then Glen noticed that the cows' manure was perfectly digested - there were no kernels of corn or longer fibers passing through, and no signs of acidosis - which indicated that the rumen was functioning properly and that the cows' diarrhea was a result of a problem somewhere else in the digestive tract.
At this point, the cows' manure had now been loose for several days. The cows, the barn, our barn clothes, and even our dog, were a royal mess. I got a text message from Glen one morning while I was at school that said, "I don't like cows today. There is crap everywhere."
To make the matter worse, now their intakes were dropping and so was milk production. And Glen was really starting to worry. He said he woke up every morning wondering if he was going to find a cow off feed when he got to the barn. (One cow did develop a DA before this ordeal was over, but we figured that wasn't too bad considering how poorly the cows were eating.)
And then there was the refusal issue. We normally feed for zero refusal, both because it makes sense economically and because hauling refusal back out of the barn is an extra chore. But now, we had half a ton of refusal to deal with each day. Then, when the short bred heifers, who normally eat anything and everything, wouldn't even eat the refusal, Glen started questioning our protein mix.
He asked our nutritionist if all of this could be the result of too much salt in the ration. Our nutritionist said it probably wasn't salt, because salt is a self-limiting ingredient. If there was too much salt, the cows wouldn't be eating any of it.
"What about other mineral levels?" Glen asked. The last load of protein that had been delivered was half the size of our normal order. The mill didn't have enough of our base mix for a full order, so they brought half the order on Monday and then brought the other half of the order on Thursday. What if the mill had added the regular amount of mineral to the half-sized load?
It could be, but that seemed unlikely, since every ingredient at our feed mill is added by computer. There was no room for human error. Glen called and asked anyway and was told that, according to the record for that load, proper amounts of all ingredients had been added.
So, then we sent a sample of our TMR into the lab. Everything looked normal on the preliminary report. We had to wait a day for the mineral analysis to be completed.
Our nutritionist got the mineral analysis results before we did. He sent Glen a text message that said the magnesium level in the TMR was four times higher than it should have been. Since magnesium is a laxative, that would explain the cows' diarrhea.
That explanation was confirmed when a sample of the protein mix from our bin and the retain sample from the mill both came back with elevated magnesium levels.
I'm not sure I can adequately describe just how upsetting this news was, but we realize that mistakes happen, even when the best protocols are used to prevent them.
There's no explanation of how the extra magnesium got into our mix, but at least we know now what was wrong with our cows. Another dairy farming mystery has been solved.
Most of the cows are eating and pooping normally again, for which, I'm sure, they are as thankful as we are. I can only imagine how uncomfortable they must have been. Milk production has returned to normal and so has Glen's blood pressure.
Now, all that's left is cleaning up the mess. We can't wash the barn or the cows until the weather warms up, so, until then, we've been doing the best we can with a curry comb.