Path 2 - Alimentary 5

drraythe's version from 2016-03-16 00:38

Abomasum continued

Question Answer
What are the 2 main abomasal parasites mentioned?Haemonchus contortus & Ostertagia ostertagi
Haemonchus contortus is aka? How do the worms obtain nutrition? What are CS & symptoms of an animal effected by haemonchus?Aka barber pole worm. Is a BLOOD SUCKER!
ANEMIA(→ extremely pale conjunctiva & viscera)
HYPOPROTENEMA(→ Subcutaneous edema/submandibular edema aka bottle jaw)
Fluid in body cavities & mesenteries
What do the lesions in the abomasum look like for haemonchus?Abomasal folds edematous, pinpoint hemorrhages over mucosa, large number of parasites in gastric digesta & attached
What does bottle jaw indicate?Submandibular edema indicates hypoprotenemia, which isnt specifically diagnostic for a particular parasite, but does point to a blood sucker. (Think: ostratagia or heamonchus)
Ostertagia ostertagi is a parasite of the abomasum, what are the 2 manifestations?Type I ostertagiasis & Type II ostertagiasis
What happens in Type I ostertagiasis?3rd stage larvae exsheath in the rumen & enter glands of the abomasum. 5th stage larvae emerge from glands in about 3 wks
If you were an ostertagia, which manifestation would you probably prefer?Type II, bc this type has "hypobiosis" which means the larvae can halt development until more favorable environmental conditions arrive
What happens in Type II ostertagiasis?3rd stage larvae exsheath in the rumen & enter glands of the abomasum. Larval development is inhibited & 4th stage larvae stay in glands for weeks to months before molting & reemerging (*hypobiosis*). Large numbers of parasites emerge at once w/ much mucosal damage
What is hypobiosis? When do you see this?"Arrested stage of development" see this in Type II ostertagiasis (causative parasite: Ostertagia ostertagi)
What do gross/microscopic lesions look like in an EARLY infxn of Ostertagia?Mucosa reddened & edematous w/ small flecks of fibrin over the mucosal surface of the abomasum
What do gross/microscopic lesions look like in a LATE infxn of Ostertagia? (What damage has happened where? (2) What does the mucosa look like? What results from the damage?)Larvae cz irritation of the abomasal glands & there is loss of parietal cells(HCl producing cells) & hyperplasia of mucus cells of the glands. (This results in abomasal alkalosis, leading to digestive probs) There is also hyperplasia of lymphoid aggregates in abomasal wall. In severe cases the mucosa looks like Morocco leather. Fluids & proteins through damaged mucosa
Explain the pathophysiology of ostertagia. (How does it damage the mucosa & what does that lead to?)Parasites are in glands → 1st cz damage/flattening of epithelium. Then the parietal cells are chronically damaged & are replaced by mucous cells. This means there is a loss of acid production. So the pH of the abomasum ↑ → maldigestion. Also loss of protein rich fluids from the damaged mucosa → Hypoproteinemia & edema
What are the 3 bacteria he mentioned that cz abomasitis?Salmonella typhimurium
Clostridium septicum
Clostridium perfringens Type A
Salmonellosis leading to abomasitis usually happens at what age? What are lesions? & pathology? What is the main presentation (where)?Usually in young calves. (only a young, dumb calf would know it isnt supposed to eat salmon. or you know, shitty immure system) There is inflammation & ulcers! Fibrin forms over the surface of the ulcers. These things result in abomasal edema & hyperemia. The usual presentation is intestinal
Clostridium septicum czs what, in who?Braxy in sheep
Clostridium septicum is usually in what geographic location? How does it attack the abomasum & how does the abo appear? Concurrent dzs?Northern US (other countries w/ cold climates). (BRaxy BRRrR) Clostridial invasion of damaged mucosa w/ production of exotoxins. Serosa of abomasum congested. Mucosal folds edematous, hemorrhagic & necrotic. Emphysema
Clostridium perfringens Type A affects who? Leads to what conditions?Affects calves. Leads to tympany, abomasitis. Congestion, hemorrhage, erosion & ulceration
*This bact is anaerobic & produces gas, will see bubbles of gas in infected tissues
When do you usually see Mycotic abomasitis?It is a 2° infxn, often seen after grain overload
Which organisms are usually responsible for mycotic abomasitis? What are some lesions youd see?By Zygomycetes (Rhizopus, Absidia, Mucor, Aspergillus). Deep ulcers-vessel invasion. Lesions often have a bulls eye appearance
What is the most common neoplasia of the abomasum? What is the other, rare one?Most common is a lymphoma. Rarely an adenocarcinoma
What does the abomasum look like when its infiltrated w/ lymphoma?Mucosal folds thickened & multifocally ulcerated. On cut surface mucosal folds are thickened w/ a whitish to pale tan cellular infiltrate.
Bubbles of gas in infected tissuesClostridia (Type A was what the pic was)


Question Answer
What do Paneth cells do? Who has these cells?Secretory & phagocytic fxn, present in horses, rodents & ppl. Their secretions are toxic to bacteria
Enterochromaffin cells do what?Endocrine secretions (Produce serotonin, catecholamines, gastrin, serotonin, etc)
M-cells do what?Covers GALT (transport of Ags to the GALT) ("moving")
Where do inflammatory cells like to live in the intestine? WHAT are the main inflammatory cells?Like to be in the lamina propria. Usually lymphocytes & B-cells. (Neutrophils transient, eosinophils during hypersensitivity & parasitic activity)
What is GALT? Where is it mostly?Gut-associated lymphoid tissue. Inclds Peyer’s patches – most extensive in the ileum
What does mucin do?Prevents adherence of organisms
What is atresia? What presentation is it usually? Where does it most commonly occur & in who most commonly?Failure of opening. Usually segmental. Can occur anywhere in the intestine but most commonly occurs in the terminal rectum (atresia ani) - most common in pigs
What is happening in Persistent Meckel’s diverticulum?Remnant of omphalomesenteric duct (aka vitelline duct. yolk to midgut)-distal small intestine
Congenital aganglionic megacolon...aka? Happens when, to who?Aka: Equine Lethal White Syndrome. If 2 overos have a baby, it might be a "lethal white foal" (white or nearly white). At 1st they appear normal, but due to a defect in the GI nervous system, they cant pass any solids (the meconium) & w/in a day or 2 begin to colic & then die
Congenital aganglionic megacolon → what is the exact mechanism by which there is a problem?Problem has been shown to lie in a mutation in the endothelin B receptor gene. Has an effect on production and/or migration of precursor ganglia cells. This czs fxnal ileus (cant be motile) anywhere btwn the ileum & distal large colon. No peristalsis bc no myenteric & submucosal enteric ganglia to send the signal to move
The it takes after eating to vomit might tell us what about an intraluminal foreign body?It’s relative location
Linear foreign bodies are common in who? What happens?Common in cats. Linear foreign bodies cz accordion folding along string (plication). String also cuts through gut wall → peritonitis
Enteroliths are aka? Where/who are they common? What do they look like? What are they made of? What can happen?Aka fecoliths. Common in the large colon of older horses. They are hard, round, green & mainly composed of Magnesium ammonium phosphate (struvite). Commonly get lodged at pelvic flexure & beginning of small colon → colic
What are Trichobezoars? Phytobezoars?Hairball obstruction/plant wad obstruction
What kinda parasites can cz intraluminal obstructions?Roundworms/tapes in young animals, especially heavy infestations & esp right after they are treated for it-all the dead bodies of the worms clump up & block off the lumen
Intestinal impaction usually in who? Usually happens where, w/ what stuff? (3)Large intestine of horses
Dry digesta
Intestinal impaction in small animals usually happens why & what are the results?Impaction in the rectum (constipation) 2° to prostatitis. The inflammation makes it painful to defecate & the animal does not. Feces become dry & rectum becomes impacted. Megacolon/rupture in some cases of impaction.
How might you treat a constipation in small animals due to a Prostatic Hyperplasia?Castration! & then ABx
What are 4 intestinal WALL lesions/problems which can cz an impaction?(1) Strictures 2° to scarring
(2) Intramural neoplasms
(3) Intramural inflammation
(4) Muscular hypertrophy of the ileum
What is a commonly occurring example of strictures 2° to scarring, which czs impaction? Czs?Often happens in PIGS infected w/ Salmonella typhimerium/cranial hemorrhoidal artery. They get a rectal STRICTURE.
What are some intramural neoplasms which can CZ impaction? Most common in who?Adenocarcinoma
Lymphoma (in class he said this is in cats a lot. Can happen in peyers patches)
1° neoplasms most common in cats/dogs
Intramural inflammation which can cz an impaction often occur when?2° to bacterial or fungal, Pythium (oomycete-not technically a fungus) infxns (widespread damage)
Muscular hypertrophy of the ileum usually happens in who?Pigs & horses
What are 4 czs of EXTRAMURAL obstructions? (Small detail about each)(1) Adhesions following Sx (usually in horses. If you leave a Sx sponge in, fibrous tissue deposited, can obstruct)\
(2) Lipomas (problem in old horses!)
(3) Neoplasms
(4) Mesenteric fat necrosis (fat is hard, puts pressure on GI. common in CATTLE)
What is Intussusception?1 segment of the intestine becomes telescoped w/in a distal segment
Intussusception → Intussusceptum vs Intussuscipiens?Tum = trapped segment
Iens = enveloping portion
What is the cz of Intussusception? (sp diffs?)Cz is generally unknown but is believed to be 2° to irritability & hypermotility (enteritis & irritability due to parasites, foreign bodies, dogs, can be czd by handling of the small intestine during Sx)
What must you differentiate Intussusception from? How do you tell the diff?Need to distinguish it from postmortem invaginations (gut can have some peristaltic mvts a few hrs after death.) Diff? If there is an infarction/dead red looking intestine, it's real. & if real, you cant pull it out again, bc it's so swollen. Postmortem wont have blood flow or swelling & it pulls out easy.
How do you generally Tx an Intussusception?Sx to remove portion that was Intussuscepted (it is usually damaged & infarcted)
Where do you usually see Intussusception in a horse?Ileum intused. Into the cecum. Often associated w/ anoplocephal perfoliata (tapeworm)
What is an Adynamic Ileus? What kinda lesion would you say an Adynamic Ileus is?Loss of normal peristalsis & muscle tone → ie, it stops moving! Biochemical lesion, not a structural lesion.
What are some possible czs of an Adynamic Ileus? (3)(1) Manipulation of stomach or intestine during Sx
(2) Severe pain, peritonitis, shock, uremia
(3) Electrolyte imbalances (hypokalemia)
What are some CS of adynamic ilues?Anorexia, abdomen distended, colic, no bowel sounds, fluid & gas in intestine, vomiting & reflux
Displacement of intestinal loops through a foramen → INTERNAL spaces of incarceration → common example of this which happens most often in HORSES? Explain where the displacement is occurringEpiploic foramen in horses. Is it the hole by which there is communication btwn the omental bursa & peritoneal cavity. (Dorsal wall formed by the caudate process of the liver & the caudal vena cava. Ventral wall formed by pancreas, hepatoduodenal ligament & the portal vein → Potential foramen)
Aside from Epiploic Incarcerations in horses, what other internal Herniations/incarcerations/strangulations can happen in horses?Mesenteric tears in horses (portions of small (or rarely large) intestine can find their way through the tear in the mesentery & become entrapped. There can be partial to complete compromise in blood flow resulting in ischemic necrosis on occasion)
Pedunculated lipomas in horses (basically same)
What is an EXTERNAL displacement of intestine usually called? What are 5 types/locations for this?A hernia!
(1) Umbilical hernia
(2) Diaphragmatic hernia
(3) Scrotal hernia
(4) Tear in muscle wall of the abdomen (& herniate through that)\
(5) Perineal hernia
Is an Umbilical Hernia a problem?Minor ones usually arent, but the bigger they are the worse it can be. You can usually fix these before they cz probs tho, easily visible
What is a particular vascular dz of the intestines which is specific to horses?"Verminous arteritis" which can lead to thrombosis or aneurisms. The main cz of this is Strongylus vulgaris ("blood worms"). Usually the worm will cz an embolus, which will throw a clot & cz ischemia/necrosis of that supplied portion of intestine
What is Volvulus?Twisting of the intestine on its mesenteric axis
What is Torsion?Rotation of a tubular organ along its long axis
What is the result of Torsion/Volvulus? (Incld timeframe). What is a possible sequale if you fix it?Infarction & necrosis of bowel wall in 6 hours. When you restore flow, a reperfusion injury can take place, which is when there is free radical damage after blood flow is restored.
What is Lymphangiectasia? Who does it happen to? What czs it?"Pathologic dilation of lymph vessels." Which usually happens in DOGS. 2 possible czs are:
(1) Congenital malformation of lymphatic system
(2) Acquired condition 2° to inflammatory/neoplastic condition of intestine/mesentaries where lymphatic fxn is compromised
What is "Brown dog gut"? What czs it/what is going on?Hypovitaminosis → intestinal lipofuscinosis
What is Hemomelasma ilei?Fibrovascular serosal plaques which may be 2° to the migration of strongyle larvae. He said it was a "non lesion" & altho it looks like something, it is nothing
What is Porcine Intestinal Emphysema?Accumulation of bubbles of gas beneath the serosa of the small intestine. Cz unknown (not really pathological he said, its just a thing, no big deal w/ meat inspection or anything)
What are the 5 main cancers associated w/ the intestines/exit of intestines?(1) Adenoma/adenocarcinoma
(2) Leiomyoma, leiomyosarcoma
(3) Lymphosarcoma
(4) Perianal gland carcinoma/adenocarcinoma
(5) Anal sac carcinoma