DIGESTIVE SYSTEM FUNCTION
Learn about the benefits of enzymes for Fibromyalgia. Neither gene in the pair is working properly, which causes the symptoms of the disease. Add a diagonal line to indicate the muscular valve, called the pyloric sphincter, between the duodenum of the small intestine and the stomach. Most of the blood is returned to the liver via the portal venous system for further processing and detoxification before returning to the systemic circulation via the hepatic veins. People with celiac disease cannot eat gluten, a protein found in wheat, barley, and rye. Depending on the cause of colic, IV fluids may be needed for several days until intestinal function has returned, electrolyte concentrations are balanced, and the horse can maintain its fluid needs by drinking.
DIGESTIVE SYSTEM ANATOMY
The epiploic foramen, a natural opening between the portal vein, the caudal vena cava, and the caudate lobe of the liver, can be the site of intestinal incarcerations. Finally, there is a natural space between the dorsal aspect of the spleen and the left kidney. This space is bounded by the renosplenic ligament, a strong band of tissue that connects the dorsomedial aspect of the spleen with the fibrous capsule of the left kidney.
Normograde peristalsis in the left ventral colon moves ingesta toward the left dorsal colon, and the muscles in the wall of the left dorsal colon contract to move the ingesta toward the diaphragmatic flexure. There is evidence, however, that the muscles in the left ventral colon contract in a retrograde fashion, from the pelvic flexure region toward the sternal flexure.
Furthermore, these contractions appear to originate from a pacemaker region in the pelvic flexure. It has been hypothesized that this pacemaker senses either the size or the consistency of the feed particles in the ingesta and then initiates the appropriate motility pattern. If the ingesta has been digested sufficiently, it is moved in a normograde direction; if additional digestion is necessary, the ingesta is moved in a retrograde direction to retain it in the ventral colon.
This theory has been proposed to help account for the common clinical occurrence of obstruction at or near the pelvic flexure. Numerous clinical signs are associated with colic. The most common include pawing repeatedly with a front foot, looking back at the flank region, curling the upper lip and arching the neck, repeatedly raising a rear leg or kicking at the abdomen, lying down, rolling from side to side, sweating, stretching out as if to urinate, straining to defecate, distention of the abdomen, loss of appetite, depression, and decreased number of bowel movements.
It is uncommon for a horse with colic to exhibit all of these signs. Although they are reliable indicators of abdominal pain, the particular signs do not indicate which portion of the GI tract is involved or whether surgery will be needed. A diagnosis can be made and appropriate treatment begun only after thoroughly examining the horse, considering the history of any previous problems or treatments, determining which part of the intestinal tract is involved, and identifying the cause of the particular episode of colic.
In most instances, colic develops for one of four reasons: This stimulates the stretch-sensitive nerve endings located within the intestinal wall, and pain impulses are transmitted to the brain. Under such circumstances, proinflammatory mediators in the wall of the intestine decrease the threshold for painful stimuli. The list of possible conditions that cause colic is long, and it is reasonable first to determine the most likely type of disease and begin appropriate treatments and then to make a more specific diagnosis, if possible.
The history of the present colic episode and previous episodes, if any, must be considered to determine whether the horse has had repeated or similar problems or whether this episode is an isolated event.
The duration of the present episode, the rate of deterioration of the horse's cardiovascular status, the severity of pain, whether feces have been passed, and the response to any treatments are important pieces of information. The physical examination should include assessment of the cardiopulmonary and GI systems. The oral mucous membranes should be evaluated for color, moistness, and capillary refill time.
The mucous membranes may become cyanotic or pale in horses with acute cardiovascular compromise and eventually hyperemic or muddy as peripheral vasodilation develops later in shock. The membranes become dry as the horse becomes dehydrated. The heart rate increases due to pain, hemoconcentration, and hypotension; therefore, higher heart rates have been associated with more severe intestinal problems strangulating obstruction.
However, it is important to note that not all conditions requiring surgery are accompanied by a high heart rate. An important aspect of the physical examination is the response to passing a nasogastric tube.
Because horses can neither regurgitate nor vomit, adynamic ileus, obstructions involving the small intestine, or distention of the stomach with gas or fluid may result in gastric rupture. If fluid reflux occurs, the volume and color of the fluid should be noted. In healthy horses, it is common to retrieve The abdomen and thorax should be auscultated and the abdomen percussed. The abdomen should be auscultated over several areas cecum on the right, small intestine high on the left, colon lower on both the right and left.
Intestinal sounds associated with episodes of pain may indicate an intraluminal obstruction eg, impaction, enterolith. Gas sounds may indicate ileus or distention of a viscus. Fluid sounds may indicate impending diarrhea associated with colitis. A complete lack of sounds is usually associated with adynamic ileus or ischemia. Percussion helps identify a grossly distended segment of intestine cecum on right, colon on left that may need to be trocarized. The respiratory rate may be increased due to fever, pain, acidosis, or an underlying respiratory problem.
Diaphragmatic hernia is also a possible cause of colic. The most definitive part of the examination is the rectal examination. The veterinarian should develop a consistent method of palpating for the following: The intestine should be palpated for size, consistency of contents gas, fluid, or impacted ingesta , distention, edematous walls, and pain on palpation. In healthy horses, the small intestine cannot be palpated; with small-intestinal obstruction, strangulating obstruction, or enteritis, the distended duodenum can be palpated dorsal to the base of the cecum on the right side of the abdomen, and distended loops of jejunum can be identified in the middle of the abdomen.
A sample of peritoneal fluid obtained via paracentesis performed aseptically on midline often reflects the degree of intestinal damage. The color, cell count and differential, and total protein concentration should be evaluated. Normal peritoneal fluid is clear to yellow, contains The age of the horse is important, because a number of age-related conditions cause colic.
The more common of these include the following: Ultrasonographic evaluation of the abdomen may help differentiate between diseases that can be treated medically and those that require surgery.
The technique also can be applied transrectally to clarify findings noted on rectal palpation. In foals, echoes from the large colon and small intestine are commonly identified from the ventral abdominal wall, whereas only large-colon echoes are usually seen in adult horses. The large colon can be identified by its sacculated appearance. The duodenum can be identified in the tenth intercostal space and traced around the caudal aspect of the right kidney.
The jejunum is rarely identified during transabdominal ultrasonographic examination of normal adult horses, whereas the thick-walled ileum can be identified by transrectal examination. The most common abnormalities identified by ultrasonography include inguinal hernia, renosplenic entrapment of the large colon, sand colic, intussusception, enterocolitis, right dorsal colitis, and peritonitis. Stallions with inguinal hernia have incarcerated intestine on the affected side; it is possible to identify the intestine and to obtain information concerning the thickness of its wall as well as the presence or lack of peristalsis.
In horses with renosplenic entrapment of the large colon, the tail of the spleen or the left kidney cannot be imaged, or the gas-filled large colon is present in the caudodorsal aspect of the abdomen in the region of the renosplenic space. Horses with sand colic have granular hyperechoic echoes originating from the affected portion of the colon. Very often the intestine proximal to the intussusception is distended, and the strangulated portion is thickened.
Horses with enterocolitis frequently have evidence of hyperperistalsis, thickened areas of the bowel wall, and fluid distention of the intestine. In contrast, horses with right dorsal colitis commonly have marked thickening of the wall of the right dorsal colon. In horses with peritonitis, the peritoneal fluid may be anechoic, or there may be evidence of flocculent material and fibrin between serosal surfaces of the viscera. Horses with colic may need either medical or surgical treatments.
Almost all require some form of medical treatment, but only those with certain mechanical obstructions of the intestine need surgery. The type of medical treatment is determined by the cause of colic and the severity of the disease.
In some instances, the horse may be treated medically first and the response evaluated; this is particularly appropriate if the horse is mildly painful and the cardiovascular system is functioning normally.
Ultrasonography can be used to evaluate the effectiveness of nonsurgical treatment. If necessary, surgery can be used for diagnosis as well as treatment. If evidence of intestinal obstruction with dry ingesta is found on rectal examination, a primary aim of treatment is to rehydrate and evacuate the intestinal contents. If the horse is severely painful and has clinical signs indicating loss of fluid from the bloodstream high heart rate, prolonged capillary refill time, and discoloration of the mucous membranes , the initial aims of treatment are to relieve pain, restore tissue perfusion, and correct any abnormalities in the composition of the blood and body fluids see Table: If damage to the intestinal wall as a result of either severe inflammation or a displacement or strangulating obstruction is suspected, steps should be taken to prevent or counteract the ill effects of bacterial endotoxins that cross the damaged intestinal wall and enter the bloodstream.
Finally, if there is evidence the colic episode is caused by parasites, one aim of treatment is to eliminate the parasites. Adapted, with permission, from Zimmel DN, Management of pain and dehydration in horses with colic. In most cases of colic, pain is mild, and analgesia is all that is needed. In these instances, the cause of colic is presumed to be spasm of intestinal muscle or excessive gas in a portion of the intestine.
If, however, the pain is due to an intestinal twist or displacement, some of the stronger analgesics may mask the clinical signs that would be useful in making a diagnosis. For these reasons, a thorough physical examination should be completed before any medications are given.
However, because horses with severe colic or pain may hurt themselves and become dangerous to people nearby, analgesics often must be given first. Additionally, many horses with less severe problems may need pain relief until the other treatments have time to be effective. Medications used commonly for abdominal pain are NSAIDs that reduce the production of prostaglandins. When these drugs are used as recommended, their toxic effects on the kidneys and GI tract occur infrequently.
Clinical experience suggests that flunixin meglumine may mask the early signs of conditions that require surgery and, therefore, must be used carefully in horses with colic. Within a few minutes after administration, the horse stands quietly and is less responsive to pain. Unfortunately, the effects of xylazine are short-lived, and it inhibits intestinal muscular activity; it also decreases cardiac output and thus reduces blood flow to the tissues.
Of the narcotic analgesics, butorphanol is used most often in horses with colic. Butorphanol has few adverse effects on the GI tract or heart.
However, when given in large doses, narcotics can cause excitement, and the horse may become unstable. Although pain relief usually is provided by analgesics, there are other important ways to reduce the degree of pain. For example, passing a nasogastric tube also an important part of the diagnostic evaluation may remove any fluid that has accumulated in the stomach because of an obstruction of the small intestine.
The removal of this fluid not only relieves pain from gastric distention but also prevents rupture of the stomach. Horses with displacement of the colon over the renosplenic ligament ie, left dorsal displacement of the colon may benefit from administration of phenylephrine. It is called the "enteric nervous system" and it is a very sophisticated piece of your biology that is wired to your brain in intricate ways.
Messages constantly travel back and forth between your gut-brain and your head-brain, and when those messages are interfered with in any way your health will suffer. Fourth, your gut also has to get rid of all the toxins produced as byproducts of your metabolism , which your liver dumps into bile. If things get backed up when you are constipated, you will become toxic and your health will suffer.
And last but not least, your gut must break down all the food you eat into its individual components, separate out the vitamins and minerals, and shuttle everything across the one cell-thick layer mentioned above so it can get into your bloodstream and nourish your body and brain. Your gut has quite a lot to manage. Even in perfect world it is hard to keep all of this in balance. But in our modern world there are endless insults that can knock our digestive systems off balance; it is that much more difficult to maintain excellent digestive health.
To fix your digestion, you first need to understand what is sending your gut out of balance in the first place. The list is short:. But what's important to understand is that many diseases that seem to be totally unrelated to the gut — such as eczema or psoriasis or arthritis — are actually CAUSED by gut problems.
By focusing on the gut, you can get better. Here is an example …. Allison, one of my patients who suffered from eczema — a weepy, red, oozing, scaly, itchy rash — all over her body is perfect example of what can happen when your gut is out of balance and the extraordinary level of healing that can occur when you fix your digestion.
This woman, who saw doctor after doctor, put salves, lotions, and potions on her skin and gave her steroids and antibiotics. But none of them ever addressed the underlying cause of her problem. Allison was 57 years old and had been suffering from severe, unrelenting eczema for eight years. She ate a high-sugar diet and had a history of frequent vaginal yeast infections.
When I saw her, I checked her gut and found she had a leaky gut — that one-cell thick lining in her intestines was breached and wasn't working properly. She had developed 24 IgG food allergies, and her stool had no healthy bacteria and an overgrowth of yeast from years of taking antibiotics. She also had very high blood levels of antibodies against yeast.
Amino acids may be classified into groups, depending upon their optical rotatory characteristics i. Levorotatory amino acids are absorbed extremely rapidly—much more rapidly than are dextrorotatory amino acids. In fact, levorotatory amino acids are absorbed almost as quickly as they are released from protein or peptide.
Neutral amino acids have certain structural requirements for active transport, and if these specific structural arrangements are disturbed, active transport will not occur.
Basic amino acids, which have a pH above 7, are transported at about 5 to 10 percent of the rate of neutral levorotatory amino acids.
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Please note that our editors may make some formatting changes or correct spelling or grammatical errors, and may also contact you if any clarifications are needed. Proteins The digestion of protein entails breaking the complex molecule first into peptides, each having a number of amino acids , and second into individual amino acids.
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