Forestomach Diseases

Question 1

T or F: acute ruminal tympany is an emergency

Answer 1

true!! needs urgent treatment

Question 2

it is easy to ______ bloat but it is difficult to _____

Answer 2

diagnose, diagnose the underlying cause

Question 3

What is a good quick way to check for bloat visually?

Answer 3

get to the backend of the cow and look for a round swelling or the rumen on the dorsal lefthand side of the abdomen

Question 4

briefly explain the pathophys behind acute ruminal tympany (bloat)

Answer 4

rumen constantly produces methane gas which the cow can deal with by eructating. If the cow cannot eructate, this is when gas builds up, compressing the diaphragm and caudal vena cava, leading to eventual CV and pulmonary collapse if not treated.

Question 5

so, you notice the cow is bloated cuz youre the best dr ever, what do you do next???

Answer 5

pass a stomach tube. If gas is relieved immediately it is gas bloat, if not, it is probably frothy bloat

Question 6

what are the 3 kinds of free gas bloat?

Answer 6

functional (cow can’t burp)
obstructive (something in esophagus?)
the cow might be upside down (gas pocket in the wrong place, solved by tipping them upright)

Question 7

what are the 2 kinds of obstructive free gas bloat?

Answer 7

intraluminal/choke–>potatoes, turnips, etc

extraluminal (abscess compressing esophagus, lymphoma, swelling in the neck, etc)

Question 8

you are called in to look at a cow that appears bloated. this happened rather acutely according to the producer and the cow isn’t eating anything. You pass a stomach tube and do not get any gas coming back out. What do you do next?

Answer 8

this is likely frothy bloat, so I need to give an anti-foaming agent (mineral oil, vegetable oil, poloxalene), and I need to separate the cow from its feed and monitor the rest of the herd for signs of bloat.

Question 9

if you have a cow with a persistent bloat, and when you try passing a stomach tube it just doesn’t work, what should you do next?

Answer 9

place a ruminal trochar or perform a rumenotomy, and be sure to investigate the underlying cause of the bloat which can be very difficult to do

Question 10

you are the best vet student ever and I love you. list some reasons why a calf would get acute ruminal tympany (bloat)

Answer 10

• vagal nerve damage like with pneumonia
• abdominal adhesions if there’s a urachal infection
• ruminal drinking–>esophageal groove isn’t working and milk ferments in rumen
• bloat after weaning, not transitioning them well off of milk, excessive carb intake, not enough roughage

Question 11

briefly describe what vagal indigestion is

Answer 11

it is a syndrome, NOT a diagnosis. the vagus nerve innervates most of the GI tract, and if this isn’t working normally, you get indigestion. Many many things can be the underlying cause of the nerve problem. Most recently we’ve found it is commonly NOT a nerve problem and simply just chronic indigestion

Question 12

how does vagal indigestion often present?

Answer 12

off color cow, varying degrees of Gi disease, chronic presentation, off feed or milk for a few days, otherwise systemically well

Question 13

what are the 4 types of vagal indigestion? which are proximal vs distal functional stenosis?

Answer 13

type I: failure to eructate (basically acute ruminal tympany/bloat)

type II: omasal transport failure

type III: abomasal outflow failure

type IV: generalized ileus/partial obstruction of late pregnancy

types I and II are considered “proximal functional stenosis” since this is before the abomasum. Types III and IV are considered “distal functional stenosis” since this is at the level of the abomasum or further down.

Question 14

how do each of the 4 types of vagal indigestion present?

Answer 14

type I: gas distention of rumen, dorsal left flank enlargement

type II: ventral left flank distention, fluid accumulation in the rumen

type III: fluid accumulation in abomasum then rumen, bilateral flank distention

type IV: same as III

Question 15

list an example of what could cause each of the 4 types of vagal indigestion

Answer 15

type I: ruminal tympany, more likely chronic for vagal indigestion

type II: luminal obstruction of abomasum like hardware dz or plastic bag

type III: abomasal atony following an RDA or luminal obstruction like sand

type IV: late pregnant animal with severe systemic disease

Question 16

what type of vagal indigestion would this be?

Answer 16

type I

Question 17

what type of vagal indigestion would this be?

Answer 17

type II

Question 18

what type of vagal indigestion would this be?

Answer 18

type III or IV

Question 19

describe how you diagnose and treat vagal indigestion

Answer 19

diagnosing can be just from your clinical exam and abdominal profile, but there are other things that can cause abdominal distention (not just vagal indigestion), so it’s best to try and find the underlying cause. To do this you may need to do an exploratory laparotomy, or you can ultrasound for peritonitis. Prognosis is poor if you can’t find the underlying problem.

treatment: pro kinetics like metaclopramide or trans-faunation (rumen juice transplant)

Question 20

briefly describe the pathophys of ruminal acidosis

Answer 20

normally: ingestion of carbs, rumen microbes yum yum yum into VFAs (acidic), saliva can buffer this acidity, VFAs absorbed across rumen wall and goes to the liver :)

ruminal acidosis: large amounts of starches, rumen microbes have a PARTY and exceed the buffering capacity and now we have lots of VFAs (acidic), passive absorption of VFAs to liver is overwhelmed. The pH of the rumen drops, which disrupts the rumen flora, causing a proliferation of lactic acid, making it more acidic, and the cycle continues.

Question 21

explain why each of these things happen when there’s rumen acidosis:
- CV collapse and anaerobic metabolism
- septicemia and/or endotoxemia
- metabolic acidosis
- osmotic diarrhea and dehydration

Answer 21

-because there’s lots of acid in the rumen, this increases the osmolarity, causing pooling of fluids into the Gi tract leading to decreased blood volume/hypoxemia

• the rumen wall becomes irritated and inflammaed (rumenitis), which allows bacteria to get into the blood stream

-the lactate and H+ ions from the rumen get absorbed into the blood causing blood pH to drop and blood lactate levels to increase

• the increase in osmolarity in the GI tract and pooling of fluid causes osmotic diarrhea

Question 22

what are the 3 “severity” levels of ruminal acidosis and how the animals usually present for each

Answer 22

mild acute: transient diarrhea and dehydration, off feed

severe acute: collapsed, obtunded, foul diarrhea, rumen distended and fluid filled

per-aute: found dead or comatose/unconsious

Question 23

list 3 ways in which you can treat ruminal acidosis

Answer 23

antacids/buffers such as oral bicarbonate
fluids, usually IV
rumen lavage and trans faunation (rumen juice transplant)

Question 24

what are 3 sequalae to ruminal acidosis?

Answer 24

laminitis due to circulating histamines and/or toxins, rumenitis, parakeratosis, liver abscess, polioencephalomalacia (no one knows why you get PEM)

Question 25

what is SARA? how does SARA usually present?

Answer 25

sub-acute ruminal acidosis: usually a herd level diagnosis, common in high producing dairy cows, varying definitions and diagnostic criteria, NOT referring to an individual animal

Question 26

what do cows like to eat when they have ruminal acidosis (or just arent feeling well in general)?

Answer 26

long fiber like hay

Question 27

how can you diagnose SARA?

Answer 27

most definitions go by severity of pH, for example if it’s lower than 5.5 for more than 3 hours. There’s lots of variation in rumen pH tho, so it’s better to focus on clinical signs and management history. If you’re gonna use pH, use it as adjunctive monitoring

Question 28

describe some signs of SARA (herd level signs)

Answer 28

variable feed intake, variable poo consistency, reduced rumination, undigested grain in feces, thin cows, liver abscesses, low or reduced butterfat, sorting of ration

Question 29

queen you got this i know you do. please list some risk factors for SARA

Answer 29

too much starch in ration, too little fiber in ration, oxermixing of ration, undermixing of ration, slug feeding (fed large amounts at once), rapid changes to ration, parlour feeding, inappropriate chop length