Large Animal Medicine I Bovine Gastric Disorders

Front 1

What is considered the ruminant forestomach?

Back 1

Rumen, reticulum, omasum

Front 2

What is the function of the ruminant forestomachs?

Back 2

Supply warm, moist anaerobic environment necessary for bacterial fermentation of plant structural carbs
-large and ingesta movement through them is slow

Front 3

The forestomachs are separated into various compartments for fermentation or ______.

Back 3

Forward flow

Front 4

What are 4 functions that coordinated muscular contractions in the forestomach accomplish?

Back 4

1) Mix ingesta
2) Separate gas from fluid
3) Regurgitate fibrous material for further chewing
4) Allow for outflow of nutrient rich liquor

Front 5

The forestomachs are lined with stratified keratinized squamous epithelium. this epithelium absorbs what compounds quickly and which compounds poorly?

Back 5

Quickly: non-ionized, lipid soluble molecules
Poorly: ionized, water-soluble molecules (except magnesium)

Front 6

How are the forestomachs altered in response to high energy diets?

Back 6

Surface area of epithelium slowly increases through papillation
-greater surface area allows for faster absorption of nutrients and therefore preservation of the rumen milieu (env't)

Front 7

What is papillary "burn-off"?

Back 7

Where get a decrease in papillae in response to very high energy diets
-high energy diets=papillation, this is the opposite

Front 8

What allows the rumen flora to adapt very rapidly to ferment almost any diet?

Back 8

There are over 200 species of bacteria and 40 species of protozoa that can inhabit the rumen= gives rumen flora and fauna to rapidly adapt and also have short generation time
-speed of adaption is not always in the best interest of the animal

Front 9

There positiveconnotations associated with the anatomy of the forestomach such as the large size allowing for fluid storage that allows for complete digestion of feedstuff, but what are the negative connotations associated with the anatomy of the forestomachs??

Back 9

large rumen also prevents vomition, intestinal distension and stretch on the mesentery with various types of obstruction or ileus= delays recognition of pathology by inhibiting development of certain clinical signs (colic, vomiting) and often allows severe metabolic derangement to develop

Front 10

What are the 3 volatile fatty acids that are the product of fermentation? What's the ratio of the concentration of each?

Back 10

1) Acetate 6:
2) Proprionate 3:
3) Butyrate 1

Front 11

What are the 3 products of fermentation?

Back 11

1) Volatile fatty acids
-acetate, proprionate, butyrate
2) Water
-water and VFAs absorbed across the gastric and intestinal walls
3) Gases
-CO2 and CH4

Front 12

Which volatile fatty acid produced from fermentation is gluconeogenic?

Back 12

Proprionate

Front 13

Which volatile fatty acid produced from fermentation is the stinkiest and epitheliotropic?

Back 13

Butyrate

Front 14

What VFA is produced in higher concentrations with more fibrous diets?

Back 14

Butyrate
-stinky & epitheliotropic

Front 15

What VFA production is higher with diets that have a greater dietary grain content?

Back 15

Proprionate
-gluconeogenic

Front 16

Water and VFA's are absorbed through the gastric and intestinal walls after produced by fermentation, so what happens to the gases produced in the forestomach?

Back 16

Must be removed by eructation

Front 17

How much gas is removed in an adult cow each day?

Back 17

300 L
-~100 L of gas made from fermentation + 200 L made by mixture of salivary bicarbonate w/ ruminal acid (H+ + HCO3-<--->H2CO3<--> CO2 + H20)

Front 18

What happens if you artificially feed a cow proprionate and acetate VFA's but not butyrate?

Back 18

Butyrate is epitheliotropic, so if do not get butyrate then the rumen will not fully develop
-Need butyrate to get fully formed rumen w/ papillae

Front 19

What happens to absorption rates as the rumen acidifies?

Back 19

More acidic= VFAs more likely to have H+ ion attached= unionized molecule= more readily absorbed
-more acidic the rumen the quicker it's removed from forestomach

Front 20

What separates the dorsal and ventral aspects of the rumen? What is contained in the ventral and dorsal aspects of the rumen?

Back 20

Fiber mat with fluid slowing around below fiber mat and gas sits above fiber mat

Front 21

What are the 5 components required for successful eructation?

Back 21

1) Stimulation of sensory receptors
-gas pressure, distention, roughage, fatty acids
2) Clearance of ingesta from the cardia
-reticular contraction, outflow of rumen contents
3) Eructation contraction of dorsal ruminal sac
-adequate musculature, nerve stimulation
4) Functional esophagus
5) Free gas (no froth)

Front 22

What is the function of the omasum?

Back 22

Regulator of transit b/w forestomach and true stomach (abomasum)

Front 23

What is the function of the abomasum?

Back 23

Acid digestion
-about 60% of gastric capacity in calves, 10% in adults

Front 24

If a ruminant is alkalemic, what part of the digestive tract is most likely damaged?

Back 24

Abomasum, secretes ~ 1.25 to 1.5 L/h of HCl rich fluid in adults (pH 2.0-4.0)
-pretty much only source of HCl in body

Front 25

What are the 4 particle size and outflow regulators in ruminants?

Back 25

1) Mouth
2) Reticulo-omasal orifice
3) Omasum
4) Pylorus

Front 26

What size of particles can move through the reticulo-omasal orifice into the lower digestive tract?

Back 26

<6 mm

Front 27

What are some examples of how signalment can help you get an idea of what kind of gastric disorder you might be working with?

Back 27

-most abomasal displacements are in dairy breeds of all ages and both sexes
-Fermentative disorders relate more to feeding protocol than breed (feedlot animals on higher grain ratios are more likely to get acidosis of rumen)

Front 28

*******What is the normal heart rate of a cow?

Back 28

60-80 BPM

Front 29

What aspects of history do you want to make sure and include in large animals with gastric disorders? (5)

Back 29

-feed type
-fecal quality
-weight gain
-vomiting/ regurgitation
-milk production

Front 30

What are the 6 components to the physical exam of the bovine GI tract?

Back 30

1) Signalment
2) History
3) TPR, mucous membranes
4) Posture/ behavior
5) Rumen motility
6) Tympanic resonance/ auscultation and succussion

Front 31

What is the relevance of tachycaria and dehydration in the prognosis of the Bovine GI disorders? What does HR > 96 suggest?

Back 31

-Tachycardia and dehydration= more severe disease
-HR > 96 suggests volvulus, pain or toxemia

Front 32

What does a fever in a cow with GI problems suggest?

Back 32

Infectious/ inflammatory component
-enteritis, peritonitis or compromised mucosa

Front 33

What are the primary type of bacteria in the GI tract?

Back 33

Gram negative

Front 34

What are 3 ways to analyze bovine posture/ behavior?

Back 34

1) Wither pinch test ("Scooch")
2) Xyphoid test
3) Colic signs
-early and transient w/ volvulus or intussusception

Front 35

What does an abnormal withers pinch test indicate?

Back 35

Cranial abdominal pain

Front 36

***What are 4 differentials for why a cow refuses to scooch?

Back 36

1) Liver abscesses
2) ruptured abomasum
3) Traumatic reticulitis
4) Pleuritis

Front 37

What is the normal rate of rumen contractions?

Back 37

2/ minute********
-less can indicate illness
-eating or chewing may be a little faster, little slower if haven't eaten in a while

Front 38

What are 3 causes of decreased ruminal motility?

Back 38

1) anorexia
2) Pain
3) systemic compromise

Front 39

How do you detect tympanic resonance?

Back 39

Simultaneous auscultation and percussion- listen for ping
-flick w/ finger and listen
-sound high like basketball= gas/fluid interface, normal rumen does not have enough tension to ping

Front 40

Where do you ping on the left side to check the center of the rumen? What is the shape of the rumen?

Back 40

Center: dorsal in paralumbar fossa

Shape: Elongated cranial- caudal, can extend to tuber coxae

Front 41

Where do you ping on the left side to check the center of the abomasum? What's the shape of the abomasum?

Back 41

Center: under ribs, mid-dorsal (not as high as rumen)
**if it extends to the 9th rib it is 99% abomasum****

Shape: round

Front 42

What is a rumen void? How can you distinguish it from a rumen ping?

Back 42

The great imitator
-sounds like a rumen ping, but no gas cap
-when rumen is collapsed but still pings, when animal has been off feed for long time abdomen is sucked in and sounds like a rumen ping and same location, but with rumen ping will have distension, rumen void= collapse

Front 43

Where will you hear a ping due to pneumoperitoneum?

Back 43

Paralumbar fossa, dorsal
-often present on both sides
-reverberates off abdominal fluid in viscera

Front 44

What is the most clinically significant ping you can hear on the left side of a ruminant?

Back 44

Abomasum= LDA
-others insignificant: rumen ping, rumen void, pneumoperitoneum

Front 45

Where do you ping the abomasum on the right side of a ruminant? What is the shape of the abomasum?

Back 45

Ping: Under ribs, mid-dorsal
-if extends to the 9th rib it is 99% abomasum

Shape: round

Front 46

If the abomasum is palpable per rectum, what is the most likely issue?

Back 46

Much more likely to be volvulus than displaced abomasum which are usually not palpable per rectum

Front 47

Where do you ping to check the spiral colon? What is the shape of the spiral colon?

Back 47

Right side: last rib, dorsal

Shape: round

Front 48

Where do you ping to hear the small intestine? What's the shape of the SI?

Back 48

Right side: last rib, mid-dorsal
-lots of auscultable fluid
-detect abnormalities rectally

Shape: round

Front 49

How can you tell if a ping is the the abomasum or the small intestine on the right side?

Back 49

Abomasum extends as far cranial as the 9th rib and small intestine extends as far cranial as 10th rib!!!!!!******

Front 50

Where do you ping to examine the cecum? What's the shape? How can you double check it's the cecum?

Back 50

Right side paralumbar fossa
shape: elongated oval
-double check rectally

Front 51

Where do you ping on the right side to check for pneumoperitoneum?

Back 51

Paralumbar fossa, dorsal
-often on both sides

Front 52

Can you hear a ping from air in the rectum?

Back 52

Yes, pneumorectum can cause a ping, can get if rectal is performed before hand

Front 53

What does it mean if you hear a ping in the spiral colon?

Back 53

NOTHING, this is an ileus ping which means nothing!!!!! very common

Front 54

What can a cecal ping mean?

Back 54

Could be volvulus or tympany

Front 55

How can you tell if a ruminant has fluid distention? What does it mean if you have fluid distention?

Back 55

-Fluid distention causes ventral distention caudally--> pear shape
-just means that there's fluid, can be in rumen, abomasum, uterus, SI, not saying where fluid is just that there's fluid distention

Front 56

How does a cow appear with gas distention? What does this mean?

Back 56

Gas is most commonly in rumen so gas goes dorsally and rumen is primary on the left so right side is pretty normal--> left side distended out dorsally--> apple shape

Front 57

What does a "papple" shape mean?

Back 57

Means that both the left dorsal sac in rumen is distended and there's generalized bilateral fluid distention - overall distention

Front 58

What are 5 abnormalities that can be detected rectally in cattle?

Back 58

1) Abnormal fetus/ uterus
2) Large bladder/ pulsing urethra/ painful kidney
3) Distended GI viscus
4) turgid: fluid filled loops of small intestine = obstruction or ileus
5) Balloon-like: gas-filled loops of intestine= gas-forming bacteria

Front 59

Compare the size of the Gi viscus?

Back 59

rumen, small intestine, cecum easiest > spiral colon> abomasum

Front 60

What can GI disorder in cattle can cause hypochloremia? What is the degree of hypochloremia proportional to?

Back 60

Obstruction/ ileus
-proportional to duration, completeness and proximity to the pylorus

Front 61

When does metabolic alkalosis develop due to GI disorders in ruminants?(4)

Back 61

obstruction, acidosis w/ enteritis, shock and tissue compromise

Front 62

When do animals with GI issues get hypokalemia and hypocalcemia?

Back 62

Anorexia

Front 63

When do ruminants with GI disorders get an abnormal CBC?

Back 63

Bad with inflammatory lesions or compromised bowel

Front 64

What are 3 GI disorders can be diagnosed via abdominoscentesis?

Back 64

Peritonitis
Uroperitoneum
Bowel compromise
-low yield

Front 65

How do you collect rumen fluid?

Back 65

by tube or paracentesis

Front 66

What is the normal concentration of rumen chloride?

Back 66

<20 mEq/L
-higher the number the more fluid is refluxing or the longer its ben refluxing

Front 67

What are 4 sources of rumen chloride?

Back 67

Saliva, diet, medications and *reflux

Front 68

The higher rumen chloride gets, the more it suggests what 3 things?

Back 68

1) More complete obstruction
2) Going on longer
3) Closer to the pylorus
Example:
<45 suggests impaired pyloric outflow but not necessarily obstruction (LDA)
> 45 suggests outflow obstruction, almost certainly a surgical lesion
>70 complete outflow obstruction, probably near pylorus
*useful but not practical

Front 69

What the normal rumen pH is depends on what the normal______ is.

Back 69

Diet

Front 70

What does the rumen pH measure?

Back 70

Measurement of acid produced by fermentation
*decrease in acidity through drop in fermentation is very important

Front 71

What causes a pH <4.0 in ruminants?

Back 71

Acute grain overload
97-100% grain ration

Front 72

How does increase in grain affect the rumen pH?

Back 72

The more grain in the diet the lower the pH

Front 73

How does anorexia affect the rumen pH?

Back 73

anorexia--> limited fermentation--> decreased acidity (increased pH)

Front 74

What can cause a rumen pH > 7.5 (on pasture pH= 6.4-6.8)?

Back 74

Salivary contamination (saliva is about 8.5) or there are a few toxins that are bases (urea, ammonia)

Front 75

The increase in pH due to ______ is far greater than any decrease due to abomasal reflux.

Back 75

anorexia

Front 76

What should be the normal color and smell of rumen fluid?

Back 76

Should be olive green, maybe a little yellow or brown
-smell should not be fetid or sour

Front 77

What are 3 ways to analyze rumen fluid?

Back 77

1) Sedimentation
-should take > 5 minutes to settle out
2) New Methylene blue reduction
3) Microscopic examination -for protozoa
-die off at pH~5.0 (can be too acidic of diet)

Front 78

What does a new methylene blue reduction measure? What's normal?? What does abnormal indicate?

Back 78

Measures redox potential of rumen fluid, an estimate of anaerobic microbial function, 2o parts rumen fluid to 1 part NMB
-normal < 5 minutes
-Slight longer is indicative of a microbial disturbance
-> 15 minutes= non-functional flora

Front 79

What is a normal gram stain of rumen fluid?

Back 79

90% gram negative species

Front 80

What are 6 abnormalities that can be detect on a fecal exam?

Back 80

1) Diarrhea
2) High content of large fiber pieces
3) Yellow and acrid= acidosis
4) Hairballs
5) gravel
6) Blood- hematochezia and melena

Front 81

What's the point of using an orogastric/ nasogastric tube in a ruminant with a gastric disorder/

Back 81

Release free gas or some fluid

Front 82

What is a liptack test?

Back 82

Transcutaneous centesis of a ping to check pH
<5.0 is usually abomasum
> 6.0 is usually ruminoreticulum or omasum

Front 83

What is considered indigestion in ruminants?

Back 83

Rumenoreticular disease

Front 84

What are primary abnormalities that result in rumenoreticular diseases associated with? secondary abnormalities?

Back 84

Primary: Problem w/ motor function or microbial fermentation
Secondary: problem arises from elsewhere that affects primary rumen functions
*and good motor function is necessary for good microbial digestion and vice versa

Front 85

What are 4 conditions that have a secondary effect on forestomach function?

Back 85

1) Endotoxemia, fever or depression induce anorexia and therefore rumen hypomotility
2) Abomasal or intestinal disease may inhibit ruminal emptying and create a backflow of abomasal or intestinal contents
3) Thoracic or cervical diseases may affect the esophagus or vagal nerve
4) Hypocalcemia, dehydration affect muscle function

Front 86

Normally there are 2 independent contraction cycles in the ruminant GI motor function. What rate of rumen contractions are considered the primary contractions? What are 3 things that are considered primary contraction cycles?

Back 86

1 contraction / minute
1) Double contraction of the reticulum
2) Relaxation of the ROO
3) Caudally extending contractions of the dorsal then ventral ruminal sacs

Front 87

What is the function of the primary contraction cycles in ruminants?

Back 87

Larger particles get mixed, small particles (<6 mm) pass into omasum

Front 88

How often do secondary contraction cycles occur in ruminants? What is involved in secondary contraction cycles?

Back 88

1 every 2 minutes
Caudal rumen pushing craniad, followed by eructation

Front 89

What is the function of the secondary contraction cycles?

Back 89

Expel gas (eructation)

Front 90

Ruminal contractions require neural control, which comes almost completely from the _____.

Back 90

Medulla oblongata
-little to no innate activity like there is w/ intestinal peristalsis

Front 91

Sensory and motor input for ruminal contractions both pass along the ______ nerves.

Back 91

Vagus
-splanchnic nerves may also exert an inhibitory effect during times of catecholamine release

Front 92

What does the rate of ruminal contractions depend on?

Back 92

Entirely on the ratio of inhibitory to excitatory input= NO INHERENT RATE OR RHYTHM

Front 93

What are the 5 controls of primary cycles of the rumen?

Back 93

1) Decrease in excitatory input
2) Increased inhibitory input
3) Depression of gastric center
4) Vagal lesions
5) Other- hypocalcemia, hyperglycemia

Front 94

What are 5 things that result in a decrease of excitatory input to the primary cycles of the rumen? What receptors are involved with each one?

Back 94

1) Decreased fill
-low threshold tension receptors in reticulum
2) Decreased chewing
-buccal receptors
3) High pH
-acid receptors in the abomasum
-pH drops w/ emptying, thus stimulating refilling
4) Less roughage
-"scratch factor"
5) Less fermentation
-less VFA's

Front 95

What are 3 causes of an increased inhibitory input to the primary cycles of the rumen?

Back 95

1) Overfilling
-High-threshold tension receptors
-abomasal tension receptors
2) too many non-dissociated VFA
-VFA/ acidity
3) Pain

Front 96

What are 4 causes of depression of the gastric center>

Back 96

1) Endotoxemia
2) Fever
3) pH and electrolyte abnormalities
4) CNS depressant medications

Front 97

How are the secondary cycles of contraction controlled?

Back 97

-tension receptors are triggered by ruminal gas distension, these stimulate relaxation of the cardia and the secondary cycle
-Cardiac receptors inhibit relaxation if in contact w/ feed or fluid (overfilled rumen, recumbent animal, frothy bloat).
-rapid overdistention inhibits the secondary cycles

Front 98

What are 2 terms that mean distention of the rumen by gas?

Back 98

Bloat= ruminal tympany

Front 99

What is the pathogenesis of ruminal tympany?

Back 99

Methane and CO2 gases produced during fermentation are not eructate and collect in the rumen.
*bloat is more of a clinical sign than disease

Front 100

The actual overproduction of gas that results in ruminal tympany isn't nearly as important as what 4 things (what causes bloat)?

Back 100

1) Physical obstruction of *esophagus
2) Physical obstruction of cardia
3) Motor dysfunction
4) Chemical inhibition

Front 101

What are 3 causes of physical obstruction of the esophagus that could therefore result in boat?

Back 101

Choke
Tetanus
Intrathoracic or pharyngeal masses (lymphoma abscess)

Front 102

What are 3 causes of physical obstruction of the cardia (and therefore causes bloat)?

Back 102

1) Masses around the cardia
-papillomatosis, actinobacillosis
2) Feed or fluid in contact with cardia (gas trapped in stable foam, poor ruminal outflow, animal in lateral recumbency)
3) adhesions
-traumatic reticulitis
-ruptured abomasal ulcer
-liver abscess

Front 103

*Why should you always put a ruminant in right side recumbency?

Back 103

If lay cow down on left side the feed material sloshes up to the lower esophageal sphincter and can no longer eructate so lay down on right side bc maintains a clear sphincter

Front 104

What are 4 causes of motor dysfunction that results in ruminal tympany?

Back 104

1) Hypocalcemia
2) Chronic overdistention
-vagal indigestion, undigested roughage, outflow obstruction
-muscle is wore out & stops working
3) abomasal distention
4) Vagus nerve damage

Front 105

What causes chemical inhibition and therefore bloat?

Back 105

Microbial fermentative disorders
-pH and VFA too high or too low

Front 106

What are 3 signs of ruminal tympany?

Back 106

1) left dorsal abdominal distention with filling of the paralumbar fossa and tightening of skin
2) Some signs of colic
3) Rapid, shallow breathing possible with cyanosis (rumen can impede movement of diaphragm)

Front 107

****When is bloat a primary problem?

Back 107

ONLY when respiratory function is impaired*****
-ventilation inhibited by decreased capacity of lung to expand

Front 108

What is the first thing used to try and treat ruminal tympany?

Back 108

Pass stomach tube

Front 109

When can you not pass a stomach tube in a cow with bloat? (4)

Back 109

1) physical obstruction
2) fluid distention of the rumen
3) Frothy bloat
4) Cow is in too critical condition (stress may kill)

Front 110

What should you do for an emergency case in a cow with ruminal tympany?

Back 110

Use a trochar
-left dorsal paralumbar fossa
-14 g needle, specialty trochar, surgery (if time)
-trochar holds rumen against skin to prevent rumenitis bc as rumen deflates it fall off the wall
-once trochar is in pull out style and gas releases

Front 111

What do you do to treat an animal that has ruminal tympany with frothy bloat? How do you do it?

Back 111

Must destabilize the foam:
-Poloxalene (therabloat)
-mineral oil or handsoap
-put in cow, allow her to move around, then pass a tube to release gas