I keep telling myself I wont get mad coming in here, and I did offer an apology for venting my anger in the first post, however this person assumes I am a complete naïve. I am sure you will treat your patients the same way some day using all the condescending technical jargon to explain a common sickness (Im sure you think youre the best too) (after all you are in vet school and I'm not). Well I dont want to argue with you too much because eventually you will show you know more biochemistry than me but remember,..I am not in vet school! However you are wrong that I have no experience b\c I worked on a farm my whole life, worked at a small animal hospital for 3 yrs, worked in wildlife rehabilitation for 5 yrs, and own multiple animals at home. I am also a graduate student in lab animal science, and I just finished a biochem course with some pre-meds. Now the reply below is a combination of what I know, and what I have looked up. I understand it, I dont have a 720 quantitative GRE score, so why cant I be a vet like you? I am not a know it- all, and I have much to learn, so read my post if you have time, I worked hard typing it (no studies this weekend, and I cant type too fast) for the last 45 min. If you see something wrong correct me, I'm not afraid to learn, even though I'm a bit of a meat head! LOL! 😀
Actually (from what I have learned) there are three versions of the twisted stomach. The most common, the LDA is found on the left, with a ping (Im sure you know this). The most common sign is going off grain. The second is an RDA, and it is then found on the right side. The third, and worst, is RTA which is a twisted abomasum which cuts off the blood supply and if not quickly repaired, results in a dead cow. All of these have different causes, and the breed of animal makes a difference...So what exactly is a displaced abomasum? The condition is simply when the 4th stomach (true stomach like ours) fills with gas and floats from its normal position on the belly floor up to the left (LDA) or right (RDA) just beneath the ribs. There is a characteristic ping that can be heard if striking your finger upon the ribs while you have your ear on the cow or use a stethoscope. Most DAs float up to the left (when looking at the cow from the rear), especially in the first month of lactation mainly because there is room to do so since the calf no longer takes up belly space and the rumen is not yet filled to capacity. A small portion are RDAs which is fortunate because they can be deadly (due to the internal anatomy of the ruminant belly). Please beware that either kind of DA can happen at anytime in the life of a ruminant (cow, bull, calf, goat, sheep, etc) but that RDAs seem to be more common later in lactation when most farmers arent thinking about the possibility of a twisted stomach anymore. In my experience, some kind of feed problem (molds) usually causes these late lactation RDAs. Unfortunately since most farmers dont suspect an RDA, the animal receives supplements and continues to deteriorate until metabolically very unstable and emergency surgery needs to be done, if it is possible still at all. Learn to listen for pings. The typical LDA in early lactation has two basic causes. The first type usually occurs in the first 5-12 days fresh and is due to calving difficulties (large calf, milk fever, etc) giving a retained placenta, infection, fever, ketosis, decreased gut motility and the classic LDA ping. The second type occurs independent of the calving event (all went well and cow cleaned) and happens about 2-4 weeks fresh when the cow is apparently doing really well and then all of a sudden is off-feed and twisted. This is due to ration problems of not having enough effective fiber and lots of carbohydrates (starch) that will create a rumen acidosis. This upsets the normal rumen bacteria and the cow goes off-feed with a rapid development of ketosis and an LDA quickly develops. Even though the LDA seems to come on overnight, the underlying feed problem probably was brewing for a little whileThis cow is deathly sick because of the torsion and obstruction and accumulation of fluid in abomasum, and also is sick b/c she gets hypochloremia, hypokalemia, and paradoxic aciduria and metabolic alkalosis. Think about this, the cow metabolically becomes deathly ill b/c serum chloride falls, b/c it is accumulating in the abomasum. The cow is constant HCl secretor, so H+ and Cl- go into abomasum and stay there. Serum Cl then falls, she gets hypokalemic. K+ is also going into the abomasum and she's not taking any in. Now normally cows eat a lot of potassium and kidneys normally thorw a lot of potassium away and it keeps doing it till she gets hypokalemic. she gets paradoxic aciduria, so in the face of metabolic alkalosis, where her pH is rising, you'd think the kidney would throw away bicarb but it does not, it reabsorbs it and throws away acid. Urine pH is acidic why is this happening, because of the low Cl which - causes kidneys to malfunction this way. The metabolic correction for this is to give her chloride. Don't use balanced electrolyte solution because there is not enough Cl-. also there are bicarb precursors in there too. Use sodium chloride because saline which is 0.9% salt, contains 154 mEq/L of chloride. Now, for every liter of saline we give her we're adding lots of chloride ions to her serum and ECF. that is how you combat the metabolic alkalosis - raise chloride level. She'll probably need 40-50 L of this and needs fluid because she's dehydrated. Before this was understood, they did surgery but cows died anyway so you have to treat with saline while doing surgery. How do you do the surgery? Make an incision, a right paralumbar fossa celiotomy, and abomasum is right there. It's filled with fluid and gas. If we can untwist without draining it, do that, or else drain it first. use stomach tube passed through purse-string opening into abomasal wall. You'd like to untwist so she can reabsorb all that ion rich fluid but often you have to drain it. When its done, some people do omentopexy to prevent recurrence. We do not know if that works.you know it is untwisted when the duodenum is to the right of the abomasum. compensated metabolic alkalosis is what develops in these cows.
I'd also go out on a limb to say that Texas A&M is similar though I don't have any personal experience about that. And I really don't know about other regions. I must admit that I'm more a small animal person, so I kinda find it funny to walk into someone's house and see it decked out with sheep or cow stuff, but I guess it might be the same for them if they saw all my dog and horse stuff. 
