Calf Scours Flashcards
What is the number one host factor for developing neonatal diarrhea complex (NDC)?
Level of immunity–passive transfer! Need to ingest 50mL/kg BW of colostrum within first 8-12 hrs
What are the biggest factors of enviro management assoc with NDC?
Overcrowding, poor sanitation
What are the top 5 infectious agents assoc with NDC?
Bacteria–E coli, Salmonella
Protozoa–Cryptosporidium parvum
Viruses–Rotavirus, Coronavirus
What signs are indicative of sepsis from NDC?
Enlarged unbilicus/joints, hypopyon, severe depression, injected sclera
What are common metabolic derangements of NDC?
Dehydration–hypovolemia.
Acidosis
Electrolyte abnormalities–hyperkalemia.
Hypoglycemia–negative energy balance
When NDC is caused by E coli, when are signs first seen?
Diarrhea in first 3-5 days, severe and watery
How do you diagnose what agent is causing NDC?
Culture
What is unique about the histopathology of E coli?
Bacteria only adheres to the mucosal surface, does not cause necrosis
How can you prevent NDC caused by E coli?
Control enviro for pathogen build up, ensure adequate colostrum and thus passive transfer, vaccinate dam
What is the biggest reason for septicemic E coli?
Failure of passive transfer
How do you diagnose septicemic E coli?
Fibrin in joint spaces, assess passive transfer
Where is cryptosporidium parvum found naturally?
Jejunum, ileum, cecum, and spiral colon
Where is cryptosporidium muris found naturally?
Abomasum
Cryptosporidium is not host specific and therefore ______.
ZOONOTIC
What is the signalment for cryptosporidiosis?
1-4 week old calves
What are the clinical signs of crypto?
yellow, watery, malodorous diarrhea, lasts 6-10 days
Why is crypto hard to treat with drugs?
Intracellular but extracytoplasmic, in a protected enviro frmo drugs so hard to get to it
Why can crypto cause autoinfection (unlike coccidian)?
oocysts can sporulate in the gut and are immediately infectious
Where in the gut does crypto reside?
distal SI and LI
How does crypto affect the intestinal villi?
Atrophy and fusion, causes malabsorptive diarrhea
What age is optimum sampling time for diagnosing crypto?
12 days old
What are the treatments for crypto?
Correct acid-base imbalances, fluid replacement, NO anti-crypto agent for calves right now
How can crypto be prevented?
Sanitation, hygiene, cleanliness, vaccination
What disease does clostridium perfringens cause?
Enterotoxemia
What is the morbidity/mortality of C perfringens?
low morbidity, HIGH mortality–10% affected, 100% die
What is the most common type of C perfringens?
Type C–causes segmental enteritis in calves
What is the signalment for C perfringens?
calves less than 2 weeks old, usually the healthiest/fastest growing ones
What are the clinical signs of C perfringens?
Sudden death, diarrhea from hemorrhagic enteritis, abdominal pain, depression, neuro signs
What is the pathophysiology of C perfringens? (ie why is it so deadly?)
Colostrum contains trypsin inhibitors, which prevents proteolysis of immunoglobulins and beta toxin that C perfringens produces. Calf doesn’t have enough proteases yet, which break down proteins as well as beta toxin. Clostridium grows best in a protein-rich enviro, releases enterotoxins which cause necrosis of the SI.
What pathology will you see with C perfringens enterotoxemia?
necrosis of SI, swollen/hemorrhagic mesenteric LN, petechial/ecchymotic hemorrages
How can you diagnose C perfringens?
Necropsy, anaerobic culture of intestinal samples, typing of toxins, histopath, anaerobic bacterial culture
Is treatment an option for C perfringens enterotoxemia?
Generally unsuccessful…but hyperimmune serum, fluids, IF/IM penicillin, NSAIDs
When do you vaccinate the dam to prevent C perfringens enterotoxemia?
2 injections 1 month apart, final one should be about 2 weeks prior to calving
When do you vaccinate the calf to prevent C perfringens enterotoxemia?
8, 12, 16 weeks of age on problem farms
