Large Animal Exam 2

Primary indigestion categories:

• reticuloruminal motor disorders or diseases of rumen wall

• reticuloruminal fermentive (microbial and biochemical) disorders

kinds of reticuloruminal motor disorders or diseases of rumen wall:

• traumatic reticuloperitonitis

• frothy bloat

• free gas bloat

• reticulitis/rumenitis

• ruminal parakeratosis

• obstructive indigestion

• obstruction of cardia

• obstruction of reticulo-omasal orifice

• diaphragmatic hernia

kinds of reticuloruminal fermentive (microbial and biochemical) disorders:

• inactivity of rumen microbial flora (caused by rumen impaction)

• simple indigestion

• acute ruminal lactic acidosis

• rumen alkalosis

• putrefaction of rumen ingesta

secondary indigestion is secondary due to…

systemic illness

secondary indigestion categories:

• secondary reticuloruminal motor inactivity

• secondary reticuloruminal microbiota inacativity

• abomasal reflux

rumen fluid parameters:

grain (low pH) + high protein diets (high pH) =

atony

indigestion clinical signs:

• decreased appetite

• reduced milk production

• anorexia

• dullness

• no rumination

• depressed or absent ruminal movements

• enlarged rumen

• tympany

• firm, doughy rumen

• reduced fecal output/dry feces

• diarrhea

differential diagnoses for indigestion:

• acetonemia

• TRP

• grain overload

• LDA

• right side dilation of abomasum

• abomasal volvulus

• vagal indigestion

• phytobezoars

• systemic disease

indigestion treatment:

• rumen lavage

• rumenatorics

• parasympatheticomimetics

• alkalinizing and acidifying agents

• re-establish rumen microflora

obstructive indigestion syndrome

group of motor disturbances that hinder passage of ingesta out of reticulorumen or abomasum or both

causes of outflow disorders:

• extraluminal

• intraluminal

• intramural

• nerogenic

extraluminal causes of outflow disorders:

• adhesions

• abscesses

• distortion of esophageal groove

intraluminal causes of outflow disorders:

• foreign bodies

• straw

intramural causes of outflow disorders:

• neoplasia

• inflammatory abscesses

• granulomas

neurogenic causes of outflow disorders:

• adhesions

• lesions affecting tension receptors in medial wall of reticulum

anterior stenosis

no passage of ingesta from reticulorumen to omasum and abomasum

posterior stenosis

inhibition of abomasal flow resulting in impaction

anterior stenosis is caused by ______ vagal nerve branch injury

dorsal

posterior stenosis is caused by ______ vagal nerve branch injury

ventral

reticular adhesions

mechanical impairment of reticular motility and esophageal groove dysfunction

what are causes of vagal indigestion that are believed to be secondary due to traumatic reticuloperitonitis?

1. vagal nerve injury

2. reticular adhesions

signs of omasal transport failure:

• inappetence with distention of rumen

• papple shape rumen

• reduced fecal output

• frothy bloat

how can vagal paralysis affect ingesta flow into omasum?

1. paralyzed or relaxed esophageal groove blocks flow into omasum

2. lack of pumping action of omasum to draw fluid through reticulo-omasal orifice

causes of carbohydrate engorgement in ruminants:

ingestion of highly fermentable feedstuffs in unaccustomed animals or in larger than normal amounts

which grains are most toxic?

• wheat

• barley

• corn

which grains are least toxic?

• oats

• sorghum

pathogenesis of grain overload:

• grain overload

• increased volatile free fatty acids

• decreased rumen pH and motility

• increased lactic aacid

• increased lactobacillus spp produce even more lactic acid

• increased rumen osmolarity (400 mOsm/L)

grain overload in untreated animals has a mortality of ___%

90

signs of grain overload:

• pain

• dehydration

• diarrhea

• bloat

• depression

• lameness

• scleral injection

• initial pyrexia

• tachycardia

• elevated resp rate

rumen fluid parameters in grain overload:

• pH < 5

• sour odor

• predominance of gram + bacteria

bloodwork abnormalities of grain overload:

• metabolic acidosis

• increased PCV and total protein

• azotemia

• increased AG

• decreased calcium

lactic acid accumulation in rumen draws in water leading to ______ rumen

splashy

hepatic abscess due to grain overload pathogenesis:

• lactic acidosis

• rumenitis

• bacterial access to systemic circulation

toxins that can increase in grain overload:

• histamine

• ethanol, methanol, tyramine, tryptamine (CNS depression)

• thiaminase (polio)

• endotoxins form death of gram - bacteria

grain overload treatment:

• sodium bicarb IV

• alkalinizing agents

• fluids

• rumenotomy

• rumen lavage

• antibiotics 

• antihistamines

causes of subacute rumen acidosis (SARA):

• inadequate rumen buffering

• inadequate adaptation to high carb diet

• diets with excessively long forage particles

bloat

retention of gas from fermentation due to prevention of eructation

kinds of bloat:

• foamy (primary)

• free gas (secondary)

how many L of gas do cows burp a minute?

2

causes of frothy bloat:

• lush pasture

• finely ground feedlot grains

what forages cause bloat?

• alfalfa

• red clover

• white clover

• sweet clover and alsike clover

• cereal crops, cabbage, peas, bean, young grass

foamy bloat pathogenesis:

• production of stable proteinaceous foam

• foam traps gas and prevents coalescence of small gas bubbles

• gas remains trapped in lumen that cannot be eructated

• distension→increased pressure on veins→reduced venous return and increased blood pressure

frothy bloat signs:

• distended left paralumbar fossa

• pain

• open mouth breathing

• anorexia

• salivation

• anxious

• depressed

• death

free gas bloat therapy:

• stomach tube

• sternal recumbancy

• exercise

• calcium

• rumen stimulants

• rumen trocharization or rumenotomy

stomach tube is not effective in ______ bloat

frothy

frothy bloat treatment:

antifoaming agents

what are different antifoaming agents?

• alfasure, polaxalene

• alcohol ethoxylate detergent

• peanut oil

• mineral oil

• dioctyl sodium sulfanate

bloat prevention:

• avoid grazing legumes in the morning

• graze on mixed grass/legumes

• mature pastures

• feed roughages

causes of abomasal ulcers:

• primary: unknown

• secondary

  • lymphoma

  • BVDV

  • rinderpest

  • MCF

types of abomasal ulcers:

1. nonperforating

2. ulcer causing severe blood loss

3. perforating ulcer with acute local peritonitis

4. perforating ulcer with diffuse peritonitis

what are the splits of abomasal ulcer types in adult cows:

• 1/3 type 2

• 1/3 type 3

• 1/3 type 4

abomasal ulcer signs:

• pain

• tympany

• anemia (shock in severe cases)

• tarry, black feces

• pale MM

• tachypnea and tachycardia

• fever

• bruxism

• dehydration

abomasal ulcer treatment:

• dietary changes

• rumen transfaunation

• decrease stress

• avoid steroids and NSAIDs

• treat concurrent problems

• blood transfusions

• antibiotics

• GI protectants

• H2 antagonists

what are the 2 layers of the peritoneum?

1. subserosa: CT

2. mesothelial squamous cells

stomata

lymph channels between mesothelial cells

peritoneal fluid parameters:

• 1 mL/kg BW

• 1.016 density

• < 3 g/dL total protein

• < 10,000 cells

peritonitis

inflammatory process of peritoneal cavity and its serosal surface

what are causes of chronic local peritonitis?

• acute localized peritonitis

• abomasal ulcer perforation

• post surgical

• penetrating wound

what are causes of acute diffuse peritonitis?

• traumatic reticuloperitonitis

• abomasal ulceration

• metritis→ruptured uterus

• rumenitis

• rectal perforation

• ruptured abdominal abscess

peritonitis signs:

• death

• abdominal rigidity, tenderness, distension

• scleral injection, fever, anorexia

• rumen atony and intestinal ileus

chronic localized peritonitis signs:

• decreased appetite

• decreased milk

• pain

acute diffuse peritonitis signs:

• constipation

• distended abdomen

• bilateral, pear shaped abdomen

• abdominal paracentesis

• reluctant to move

• sepsis

• tachycardia

• weak pulse

• cold

• dehydration

peritonitis diagnosis:

• abdominocentesis

• ultrasound

peritonitis treatment:

1. stabilize patient

2. identify and correct primary causer

3. treat infection by medical or surgical procedures

traumatic reticuloperitonitis

accidental swallowing of metal foreign object that penetrates reticulum leading to peritonitis

traumatic reticuloperitonitis signs:

• sudden ruminoreticuar atony and sharp fall in milk production

• decreased fecal output

• mildly increased rectal temp

• normal or slightly increased HR

• shallow and rapid resp

• pain

• kyphosis

• arched back and uneasy gait

pleurtis or pericarditis signs:

• depressed, tachycardic, pyrexic

• shallow resp and muffled lung sounds

• gas and fluid splashing sounds on auscultation

• jugular vein distension

• congestive heart failure

pleurtis or pericarditis diagnosis:

grunt when pressure is applied to xiphoid

pleurtis or pericarditis due to traumatic reticuloperitonitis diagnosis:

• antibiotics

• magnet

• confinement

• rumenotomy

what are the 2 BVDV genotypes?

• BVDV-1: used in vaccines

• BVDV-2: more virulent, hemorrhagic syndrome, death

what are the 2 BVDV strains?

BVDV has topism for acutley dividing cells such as…

• repro tissues

• fetal tissues

• GI tract mucosa

• intestinal crypts

• peripheral lymphoid tissue

• bone marrow

______% of BVDV infections occur without clinical signs

70-90

transient acute vs severe acute BVDV infection:

hemorrhagic syndrome is associated with __________ BVDV-2 severe acute infection

noncytopathic

hemorrhagic syndrome signs:

• thrombocytopenia

• bloody diarrhea

• epistaxis

• mucosal hemorrhage

• hyphema

• pyrexia

BVDV forms synergistic infections with…

mannheimia hemolytica and mycoplasma bovis

how does BVDV cause immunosuppression?

• lymphopenia: reduced helper and cytotoxic T cells, B cells, and neutrophils

• reduces ability to stimulate T cell responses

BVDV repro signs:

• fertilization failure

• embryonic death

• abortion

• persistent infections

• congenital defects

outcomes of fetal BVDV

BVDV congenital neuro defects:

• cerebellar hypolasia

• hydrananecephaly (absent cerebral hemispheres)

• hydrocephalus

• hypomyelinogenesis (inadequate myelin)

BVDV congenital ocular defects:

• retinal atrophy and dysplasia

• cataracts

• microphthalmia

• hypoplasia of optic tract

BVDV congenital immune system defects:

thymic hypoplasia

BVDV congenital skin defects:

• hypotrichosis

• alopecia

BVDV congenital musculoskeletal defects:

• growth retardation

• brachygnathism

persistently infected cow prevalence

<1%

how does mucosal disease occur?

immunotolerant PI infected with cytopathic strain

what are the 3 clinical presentations of mucosal disease?

1. acute MD

2. chronic MD

3. MD with recovery

acute MD occurs if the cytopathic strain a cow is infected with has close antigenic homology to the _________________ strain

PI noncytopathic

acute MD signs:

• near 100% mortality

• fever

• anorexia

• bloody, fibrinous diarrhea

• blunted papilla

• ulcers of tongue, palate, buccal surface, pharynx

chronic MD occurs if the cytopathic strain a cow is infected with is ____________ to the PI noncytopathic strain

heterologous

chronic MD signs:

• anorexia, weight loss

• diarrhea

• bloat

• alopecia

• erosions of mouth and skin

• lameness

BVDV diagnosis:

• virus isolation

• PCR

• antigen detection

BVDV treatment:

• supportive care

• prevent secondary infection

BVDV prevention:

• eliminate PI animals

• vaccinate

• biosecurity

when to vaccinate against BVDV:

• after 6 months of age

• prior to breeding

pros and cons of inactivated BVDV vaccines:

contain type 1 and 2

pros and cons of modified live BVDV vaccines:

contain type 1 cytopathic strain

bovine neonatal pancytopenia

calves born to cows vaccinated with pregsure BVD vaccine receive alloantibodies via passive transfer that damage bone marrow