Forestomach Diseases Flashcards
T or F: acute ruminal tympany is an emergency
true!! needs urgent treatment
it is easy to ______ bloat but it is difficult to _____
diagnose, diagnose the underlying cause
What is a good quick way to check for bloat visually?
get to the backend of the cow and look for a round swelling or the rumen on the dorsal lefthand side of the abdomen
briefly explain the pathophys behind acute ruminal tympany (bloat)
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.
so, you notice the cow is bloated cuz youre the best dr ever, what do you do next???
pass a stomach tube. If gas is relieved immediately it is gas bloat, if not, it is probably frothy bloat
what are the 3 kinds of free gas bloat?
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)
what are the 2 kinds of obstructive free gas bloat?
intraluminal/choke–>potatoes, turnips, etc
extraluminal (abscess compressing esophagus, lymphoma, swelling in the neck, etc)
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?
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.
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?
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
you are the best vet student ever and I love you. list some reasons why a calf would get acute ruminal tympany (bloat)
- 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
briefly describe what vagal indigestion is
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
how does vagal indigestion often present?
off color cow, varying degrees of Gi disease, chronic presentation, off feed or milk for a few days, otherwise systemically well
what are the 4 types of vagal indigestion? which are proximal vs distal functional stenosis?
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.
how do each of the 4 types of vagal indigestion present?
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
list an example of what could cause each of the 4 types of vagal indigestion
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
what type of vagal indigestion would this be?
type I
what type of vagal indigestion would this be?
type II
what type of vagal indigestion would this be?
type III or IV
describe how you diagnose and treat vagal indigestion
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)
briefly describe the pathophys of ruminal acidosis
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.
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
-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
what are the 3 “severity” levels of ruminal acidosis and how the animals usually present for each
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
list 3 ways in which you can treat ruminal acidosis
antacids/buffers such as oral bicarbonate
fluids, usually IV
rumen lavage and trans faunation (rumen juice transplant)
what are 3 sequalae to ruminal acidosis?
laminitis due to circulating histamines and/or toxins, rumenitis, parakeratosis, liver abscess, polioencephalomalacia (no one knows why you get PEM)
what is SARA? how does SARA usually present?
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
what do cows like to eat when they have ruminal acidosis (or just arent feeling well in general)?
long fiber like hay
how can you diagnose SARA?
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
describe some signs of SARA (herd level signs)
variable feed intake, variable poo consistency, reduced rumination, undigested grain in feces, thin cows, liver abscesses, low or reduced butterfat, sorting of ration
queen you got this i know you do. please list some risk factors for SARA
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
