Calf Problems: Infectious Diarrhoea and Other Conditions

Question 1

List four endemic calf diarrhoea pathogens.

Answer 1

Rotavirus
Coronavirus
Cryptosporidia
Enterotoxigenic E. coli

Question 2

What is the most likely agent for calf diarrhoea from 0-6 days?

Answer 2

Enterotoxigenic E.coli (ETEC)

Question 3

What is the most likely agents for calf diarrhoea from 6-21 days?

Answer 3

Rotavirus
Coronavirus
Cryptosporidium

Question 4

What is the most likely agent for calf diarrhoea from 21 days?

Answer 4

Coccidiosis

Question 5

How does rotavirus cause disease?

Answer 5

Destruction of microvilli in enterocytes

Question 6

Briefly describe the pathogenesis of rotavirus

Answer 6

NSP4 damages junctions between cells causing leakage.
Also damages functions of SGLT1.
No sufficient absorption.

Question 7

What are three aspects of the pathology of coronavirus?

Answer 7

Massive loss of intestinal epihtelium and villus stunting.
Greatly reduced absorption of intestinal fluid.
Basal crypt cells less affected, recovery can be rapid.

Question 8

What clinical signs do cryptosporidia cause and for how long does it last?

Answer 8

Profuse watery diarrhoea for about 7 days.

Question 9

List the four categories of obligately pathogenic E.coli serotypes.

Answer 9

Enterotoxigenic E.coli (ETEC)
Verotoxigenic E. coli (VTEC)
Attaching and effacing E.coli (AEEC)
Enteroinvasive E.coli (EIEC)

Question 10

Why is clinical disease due to entertoxigenic e.coli rare after cattle are over 5 days old?

Answer 10

Due to loss of receptors on the gut epithelium for E.coli adhesins/toxins

Question 11

What two substances causes paracasein to clot quickly?

Answer 11

Acid and rennin

Question 12

List 7 causes of poor clotting of casein in calves?

Answer 12

Failure of sufficient acid and enzyme secretion
Poor quality milk product
Farmer uses incorrect concentration
Farmer feeds at incorrect temperature
Feeding times irregular
Infection of the abomasum
Overfeeding

Question 13

Which pathogen causes calf diptheria and which age of calves does it occur in?

Answer 13

Fusobacterium necrophorum.
Occurs in pre-weaned calves and those up to 6-9 months of age

Question 14

What are the clinical signs of calf diptheria?

Answer 14

Necrotic infection of the oral cavity and often larynx.
Extensive salivation, some swelling, may be dull.

Question 15

How should you treat calf diptheria?

Answer 15

Penicillin

Question 16

What are the two forms of ruminal bloat in pre-weaned calves?

Answer 16

Milk fermentation in an immature rumen
Immature rumen syndrome

Question 17

What are the clinical signs of ruminal bloat in pre-weaned calves?

Answer 17

Pasty scours, bloat and colic.

Question 18

How does immature rumen syndrome present?

Answer 18

Clinically a pot-bellied appearance with thin pasty faeces

Question 19

How would you treat immature rumen syndrome?

Answer 19

Treat by drastic reduction in roughage, use shavings as bedding, palatable concentrates, inoculate rumen with adult ruminal fluid.