L23: Clinical Approach To The Toxic Cow (Maunsell)

Question 1

Toxic shock most commonly occurs when?

Answer 1

During early to peak lactation

Question 2

Most common cause of acute bacterial toxemia

Answer 2

E. Coli

Question 3

GP bacteria assoc. with toxic shock

Answer 3

Staph aureus (mastitis)
Truperella pyogenes (mastitis, metritis, peritonitis)
Clostridium (mastitis, metritis)

Mixed infections common

Question 4

Pathophys. Of GP and GN mixed infections –> toxic shock

Answer 4

-interaction of endotoxin and GP toxins with immune system –> inflammatory cascade

Question 5

Clinical consequences of toxemia due to endotoxin/GP toxins

Answer 5

Tachycardia
Anorexia and forestomach hypomotility
Diarrhea
Leukopenia (neutropenia)
Dehydration --> dec. CO and hypotension
Dec. systemic O2 delivery --> hypoxemia 
Fetal loss
Weakness
Fever

Question 6

Common causes of toxic shock in adult cattle

Answer 6

• severe clinical mastitis, metritis**
• peritonitis, enteritis, endocarditis, pneumonia
• GN bacteria endotoxin release and absorption due to GI inflammation/ischemia 2ary to grain overload, rumenitis, bowel volvulus, hemorrhagic bowel syndrome
• some GP bacteria also produce toxins