The more I learn about cows, the more fascinated I am with these large, grazing animals.
One might ask, what's so special about cows? And I would say, "Funny you should ask! Let's discuss!"
Disclaimer: there are some descriptions of therapeutic/emergency surgical procedures that some might find disconcerting and/or troubling. Reader, beware! Also, I am not a veterinarian or have any kind of animal medical background. I'm just writing from my own experience and research.
(This blog post is a good supplement to our podcast episode regarding a harrowing incident on our farm. Listen to our podcast here.)
The beauty of a cow (and other ruminant animals) is their ability to convert grass---a plant which continues to grow no matter how often you cut it down and is not nutritionally dense enough to sustain other non-ruminant animals, into a highly nutritious food source. If we, humans and other non-ruminants, also known as monogastrics (single stomach) attempted to eat grass, it wouldn't kill us, but the nutrition we'd get from eating grass would be less than the energy it took to chew the food in the first place. Not to mention that we have no mechanism to break down the cellulose fiber that makes up the majority of grass structure. We'd end up with some kind of intestinal blockage and wasted effort. But a cow, on the other hand... she has value in being able to take the free inputs of sun, soil, and water, and produce milk, a calf, and manure to enrich gardens. The book, Keeping a Family Cow by Joann S. Groman waxes poetic about cows in a way that first made this city girl so excited to have one on the farm.
To better understand this lovely animal, I'm going to delve a little deeper into the mechanism of how she digests her food: (Science time!)
Cows have 4 "stomachs" or rather 4 chambers that are used to digest food. (Other ruminants like sheep, goats, even giraffes have a 4-chambered stomach---not horses; they aren't ruminants, but they do have a modified large intestine) These chambers are the rumen, reticulum, omasum, and abomasum.
Ruminants are typically prey animals, so first step is to graze. They take in grass without chewing, as quickly as they can. That grass enters into their rumen. Once they are finished grazing, the ruminant will go somewhere safe and restful and continue the digestive process.
What happens in the rumen? It is a large organ---think 25 (plus) gallon drum kind of large, that can hold a huge amount of grass. This mixes with saliva and water coming from the adjacent reticulum. Within the rumen itself is the magic of the digestive process. It is filled with bacteria and some protozoa that are able to break down the cellulose of grass. The reticulum contracts and swallowed grass from the rumen is regurgitated up; the cow can take her time to "chew her cud."
A cow can spend up to half of its day working on the food in her rumen. The longer the fibrous material stays in the rumen, the more efficiently it is broken down. Bacteria work on the mash of grass and saliva and liquid, releasing their own gases while they metabolize the plant fibers in a process we know as fermentation. The plant fiber is broken down into acetic, propionic, and butyric acid, that directly helps with maintaining the cow's overall condition, growth, reproduction, and milk production, while methane gas is the resulting waste product.
That gas produced through fermentation is expelled through the dainty belches your cow makes throughout the day. You can hear the rumblings of her insides as they're constantly churning grass, moving and mixing and digesting it in an astonishingly efficient way. A healthy rumen is constantly churning, every couple of minutes or two. It's kind of nice just leaning your head against the side of a cow and listening. I highly recommend this.
After the cud has been properly fermented, it moves to the omasum where water and some other substances are digested and absorbed. Then, we move into the abomasum, sometimes called the "true stomach" because it performs a similar digestive function as ours, having glands that secrete hydrochloric acid and enzymes that break down food even further for absorption.
For the most part, everything functions beautifully in this cycle. However, because so much of the digestive process is dependent on the rumen, and more specifically the microbial hosts of the rumen, anything that affects them affects the overall health of your animal.
Introducing too rich of feed, like switching from field grass to a higher protein green like alfalfa, legumes, or clovers can cause bubbles or foam in the rumen. Sometimes it isn't even a richness of feed; sometimes it's a sudden change in grass types without a slow transition, pasture that is a bit dewier than usual, a noxious weed that they accidentally consume...
[Sidebar: the need for slow transitions is a common thread across this natural life. We do slow transitions with dog and cat food, with chicken grain, even with feeding my sourdough starter... it's just more difficult to adapt to a stark change rather than slowly introducing something new and acclimating to it. With cows, especially when the grass is first lush and green, we keep them in the pen and feed hay first so that they don't gorge on the fresh stuff. Same with changing hay types, we'll start introducing a flake or two for a few days before fully committing.]
Whatever the cause of distress, something in the rumen makes the gas production more active than usual. Gas produced by the bacteria can't escape by belching as they get trapped by the foam. More and more gas builds up within the rumen, blowing the cow up like a balloon until it is pressing against the heart and lungs, killing her within minutes. This is bloat. It is deadly.
Another affliction that can affect the rumen is called ruminal acidosis--usually associated with the overconsumption of grain by a cow. They're grazing animals, and by nature cows don't need to eat anything other than grass because of their very specific digestive system. Cellulose is a long fermenting food, whereas grains only require a short ferment. It's quick energy, as I'm sure many of us know. Grain had been introduced to bovines and other grazing commercially raised animals because it pushes the production of said animals. There are now breeds of cows (and goats and sheep) that have been bred to make efficient use of grain for greater meat production and higher milk output. When grain is broken down in the rumen, it produces similar fatty acids as in the breakdown of cellulose and also lactic acid. Given a smaller/controlled amount of grain, a cow can glean more readily usable energy (plus it's literally like eating cake for them), and the lactic acid production can be dealt with because it's in smaller quantities.
If however, your cow isn't accustomed to grain --- you really have to do a transition whenever introducing any kind of new food---or your animals get out and find the grain bin and gorge themselves uncontrollably (because again, it's like a dessert), then the lactic acid build up is too big and too fast. It will dangerously lower the pH (increase the acidity) of the rumen slurry. The acidification of the rumen creates a hostile environment for the beneficial bacteria and protozoa. They can die off and other less friendly bacteria can flourish. In response to the lowering pH, the reticulum starts drawing water from the rest of the body and pouring it into the rumen, trying to neutralize the acid, and the rumen again, will get bigger and bigger. Prolonged acidosis can cause permanent damage to the epithelial lining of the rumen, decreased body condition, and diarrhea; acute cases of acidosis are deadly.
So how can we identify these potentially deadly conditions? Well, it's good to identify where the rumen and assess how it's looking. Below, is a picture of Cookie in the stanchion. Her rumen is circled in blue. It is the triangle shaped depression behind the last rib and before the hip protrusion. (We say, "Left side's food; right side's baby" when trying to identify what's causing the bulges on the sides of the cow). When a cow is hungry, the rumen is more sunken in like in the picture. If it is full, it should be more filled out, sometimes closer to flush with the rib. It should not extend behind the ribs, and definitely never be in line with the bony ridges of the spinal column---that is bloat.
You can double check with sound, too. Start flicking your fingers against the cow's rumen. If it's a low, hollow, "punk, punk," sound like.... a ripe watermelon, you've got a big rumen that's full. Not at the bloated stage. But if you hear a "ping, ping"---think the sound of a basketball bouncing on the asphalt... that's too big.
What happens if your cow does get bloat? As careful as you are, as attentive as you are to what they're eating in the hay you feed or you've got your grain locked tight like a bank vault, but something somewhere somehow gets into your cow and causes bloat. What do you do?
Hopefully, you catch it early. Your cow looks a little bigger, a little uncomfortable. But they're still on their feet. Maybe a little sluggish; they just look like they're not feeling great. Then the answer is to keep them moving. Take them for a little walk around the pasture and back and forth around their pen. Don't leave them alone to sit down because sitting down is not good. You don't want your cow to be down. Keeping them moving is keeping those muscles contracting and relaxing and encouraging the movement of gases and hopefully relieving enough pressure to make things bearable and to a safe rumen condition.
If the walking doesn't work, or you catch the cow at a different stage of bloat, then the next level of treatment is with an oral treatment. There are applications of bloat treatments that come in bottles that you essentially pour down their throat called "drenches."---brand names like Therabloat or Bloat Guard, and they usually have a key ingredient of poloxalene. You can get them pre-mixed at your local farm supply/Tractor Supply type store or online wherever. (I think I've read on some homesteading forums that in a pinch if you absolutely don't have anything, a solution of baking soda and mineral oil will work, but I don't know the ratios of this) Essentially what it does is cut down the froth build up along the esophagus and rumen and allows the cow to belch. The drenches come in narrow necked bottles (like a beer bottle shape), and you put the mouth of the bottle behind the molars, keeping the head of your cow at about her shoulder level (I keep using "she" and "her" and "cow," but obviously this can also affect your bulls as well) because you don't want to drain down into her lungs. If you're facing the cow's head, keeping the bottle towards your right hand side will keep it down the esophagus. If you're holding her head in that position, you'll hear her swallowing down the drench. Try and get her to take the full dosage. And if she's bloated, she's not going to be resisting that much, and you can manipulate her pretty well.
If you apply the drench, you should start seeing if it's effective pretty soon, like within the hour or so. If you don't see or hear a change, or the bloating seems to be getting worse rather than better, next step you can try is a tube. (If you don't have a bloat drench, you straight to this option, too.) A drenching tube is a long plastic-y tube, let's say about 5 feet long that you feed through the mouth, and down the esophagus until it enters the rumen. If you don't have a drenching tube, a garden hose with the metal ends cut off works, too. To prevent the cow from grinding down on your tube with her molars and possibly damaging said tube, you can feed it through a speculum in the mouth, or a bit of PVC pipe can serve the same purpose. Again, aim for behind the back molars, on your right side when facing her mouth. When you push the tube back behind the teeth, she should reflexively start swallowing it down the esophagus, and you just feed it back. If you don't feel swallowing, or alternatively, if you hear breathing from the other end of the tube, you're in the trachea... wrong pipe. When you hit the rumen, be prepared for an expulsion of noxious gas. It sounds like air being forced out of a tire, a "whooshing" and you can literally see the cow shrink as all that gas escapes. They're usually good to go, but keep an eye on them for a day or two because sometimes they'll bloat up again or a few times more just to keep you on your toes.
But let's say the worse comes to worse. You come out to the cow pasture, and your cow, who hasn't shown any signs of being ill, is suddenly down, blown up like a beach ball and minutes away from death? What do you do?
If you have an instrument called a trocar and cannula, I would have someone run and get it. If you don't, a long sharp knife like a boning knife can also perform. In these situations, you only have a few minutes, and we can't squabble about semantics. If you have the presence of mind to sterilize whatever you're using, like with rubbing alcohol or iodine, do that. Try and envision where the rumen is---at this point, you probably can't see the ribs or the hip bone or the spinal ridge because of how enlarged the cow body is, but make the best approximation, and stab down as hard and quickly as you can in that area. This is not a time to be delicate because the cow's hide is so tough. There's less danger of hitting other organs in this condition because the rumen is so large when bloated. If you don't come down with enough force, you will literally bounce off the cow, so you have to be single-minded in your effort. Once your blade goes in, you twist to open the hide and you should hear a great whoosh of gas, and hopefully, your cow will be back on their feet soon.
The risk of peritonitis (infection of the peritoneum---the lining of the abdominal cavity) is very high with this emergency procedure, so it's absolutely a last ditch effort, and so important to have a vet come and see your animal as soon as possible. In the meantime until your vet comes, drench the wound with an iodine solution and try to keep the flies away as best as you can. The vet will examine the puncture wound and prescribe antibiotics and make sure everything is okay. It's a harrowing experience for both farmer and cow, and definitely not the first treatment option because of all the possible proceeding complications, but if it's a choice between the death of your cow or stabbing the rumen... we pick the second option.
Whenever you experience bloat with your cow or within your herd, it's important to keep an eye on them and take a critical eye to what they've been eating. It's best to switch to mature long stem hays and grasses during this time until everyone receives a clean bill of health.
I hope you never have to experience bloat. But if you do, perhaps you'll be more prepared than we were on our farm. You can hear about our harrowing adventures with bloat on our podcast, and live vicariously through our misadventures.
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