Manifestations And Management of Disease In Neonatal Ruminants p302-338 Flashcards
Septicemia is the third most common cause of calf mortality in the US. Behind what 2 other causes?
Diarrhea and respiratory
The phagocytic and bacterial killing function of neutrophils (PMNs) is decreased in calves, compared to adults. List some reasons why.
Cortisol levels are increased for the first 10 days of life, depressing neutrophil function
Lymphokines produced by CD4+ cells, IL-2, IL-4 and IFN-gamma are essential to Ag-specific immunity. Cortisol levels also depress lymphocyte proliferation and IL-2 activity
This is the most common organism isolated from a calf blood culture.
A) Salmonella
B) Camplobacter
C) Klebsiella
D) E. coli
D) E. coli
In regards to neonatal calf sepsis, the interaction between LPS and the immune system triggers and inflammatory cascade. Discuss some results of that cascade.
Production of arachidonic acid metabolites, release of myocardial depressant factors, activation of the complement system
What are the most useful parameters for predicting septicemia in calves?
Presence of toxic neutrophils, FPT, focal infection or elevated serum creatinine concentration
The CSF is poorly defended against pathogens. Why is this?
Complement is not present in the CSF; there are a minimal amount of specific Abs, which leads to inadequate opsonization of meningeal pathogens
Urinary reagent strips can be used to evaluate CSF, stall side. What should glucose levels be in the CSF?
Glucose levels should be trace or positive. If they are negative, this could suggest severe meningitis, or profound hypoglycemia.
Calves with acidosis can have two different forms of lactate contributing to their metabolic derangement. What are these forms and where are the coming from?
D-lactate can come from bacterial fermentation of carbohydrates in the GI tract
L-lactate is endogenously produced, generally due to dehydration
How can hyponatremia lead to neurologic signs?
Hyponatermia leads to a fluid shift from the ECF to ICF, leading to cell swelling and eventually lysis.
How does the IV fluid treatment of hyponatremia differ between hypovolemic calves and normovolemic calves?
Hypovolemic calves need fluid resuscitation first with isotonic saline, to not exacerbate cerebral edema. Normovolemic calves can be treated with hypertonic saline.
List 3 ways hypernatremia in calves can occur.
- Excessive loss of free water, due to dehydration, heat, sweating, water deprivation
- Iatrogenic administration of IV crystalloids without proper water consumption
- Excessive intake of sodium without proper water consumption
Ruminal bloat is uncommon in calves less than 5 weeks of age. How can bronchopneumonia cause ruminal bloat?
Severe bronchopneumonia can cause swollen mediastinal lymph nodes, compressing the esophagus or compressing/inflammation of the vagus nerve.
There are 4 types of gastric ulcers in calves. Describe these types.
Type 1: Nonperforating ulcer - intraluminal hemorrhage is minimal, abomasal wall is not perforated
Type 2: Nonperforating with severe blood loss - a major blood vessel in the submucosa has been eroded
Type 3: Perforating ulcer with local peritonitis - peritonitis localized by fibrin deposition and and the abomasum becomes adhered to the peritoneum, the omentum or surrounding viscera
Type 4: Perforating ulcers with diffuse peritonitis - ulcer perforates and quickly spread throughout the rest of the peritoneal cavity
What are some treatments that can be used in calves for abomasal ulcers? Describe their MOA as well.
Antacids - Al(OH)3 or Mg(OH)2 bind bile acids protecting ulcerated areas from bile reflux
Al(OH)3 directly binds pepsin, thus decreasing proteolytic action of pepsin in the stomach
Histamine type 2 receptor antagonists - reduction of acid secretion of parietal cells by selective and competitive antagonism of histamine at H2 receptors on the parietal cells
Cimetidine and ranitidine
What are some proposed causes of abomasal bloat in calves?
Addition of course roughage, abomasal bezoars, copper deficiency, various microorganisms i.e. C. perf type A has been isolated
What are some causes of delayed abomasal emptying in calves?
High osmolality milk replacers, feeding a large volume in a single daily feeding, poor mixing of milk replacers, offering cold milk, not offering water, erratic feeding schedules
What is the treatment for abomasal bloat in calves?
Calf in dorsal recumbency, and trocarization.
What is the most common location of intestinal atresia in calves?
Spiral loop of the ascending colon
What are some proposed causes of colonic atresia in calves?
Palpation of the amniotic sac before 40 days of gestation, autosomal recessive inheritance in Holstein cattle
Where is the most common location of intussusception in calves?
A) Duodenum
B) Jejunum
C) Ileum
D) Ileocecal junction
B) Jejunum
Match the pathogenesis of diarrhea in calves with its corresponding pathogens.
Coronavirus, E. coli, Enteric viruses, Protozoa, R. equi, Rotavirus, Salmonella
A) Stimulation of the enteric nervous system
B) Compensatory hyperplasia of the crypt cells
C) Increased intestinal secretions due to stimulation of cyclic AMP or cyclic GMP, calm oculi or protein kinase activity
D) Destruction of absorptive villous epithelial cells
A) R. equi
B) Rotavirus, Coronavirus
C) Salmonella, E. coli
D) Protozoa, Enteric viruses
Based on the MOA, and age of animal affected, what cause of calf diarrhea is described?
- Observed in calves less than 3 d old
- If concurrent infection with rotavirus, observed in calves 7-14 d old
- Two virulence factors: fimbriae and enterotoxins (LT and STa, STb)
A) ETEC
B) AEEC
C) STEC
D) EPEC
A) Enterotoxigenic E. coli
Based on the MOA, and age of animal affected, what cause of calf diarrhea is described?
- Observed in 2 d-4 wk old calves
- Cytotoxic damage to the intestinal mucosa by a Vero or HeLa toxin that induces a mucohemorrhagic colitis, with petechial or ecchymotic hemorrhages
A) ETEC
B) AEEC
C) STEC
D) EPEC
B) Attaching and effacing E. coli
Based on the following, what cause of calf diarrhea is described?
- Induction of severe inflammation of the bowel mucosa leading to dysentery and passage of mucous and fibrin casts
- Infects salivary glands and is shed in saliva and nasal secretions
- Immunity changes rapidly during the first 3 months of life
A) E. coli
B) Salmonella
C) Clostridium
D) Camplyobacter
B) Salmonella, with typhimurium causing the most clinical disease
