Farm Animal Neonatal Diseases Flashcards
What proportion of calves die before weaning?
8.8%
Which maternal-derived antibodies provide systemic protection in the calf?
IgG
IgM
Which maternal-derived antibodies provide local protection in the intestine of the calf?
IgG resecreted into the gut lumen
IgA in colostrum passes through gut lumen
What is the ideal plasma level of IgG in the calf?
5g/L plasma is protective
10g/L is aim
How does colostrum of beef cows compare to that of dairy cows?
Better concentrated
Lower volume
What percentage of a calfs body weight is blood?
8%
If colostrum has 50g/l, a calf drinks 2L and the efficiency of absorption is 30%, what is the calf’s plasma Ig concentration if it has 3L of blood?
50 x 2 = 100
100 x 0.3 = 30
30/3 = 10
10g/L
What are the major factors influencing colostrum availability?
Milking number Milk yield Dairy/beef Pre-calving milking or leakage Short dry period Premature calving Heifer/cows
Why does a short dry period reduce colostrum availability?
Poor body condition score leads to insufficient immunoglobulins absorption
How does the colostrum of heifers differ from that of cows?
Less rich
Greater volume
How might mastitis affect colostrum?
May not let calf suckle
Immunoglobulins may be denatured
Why might double muscled calves receive insufficient colostrum?
Double muscled tongue makes it hard to suckle
What does the colour of colostrum indicate?
Quality
What colour is high quality colostrum?
Dark yellow
What does orange colostrum indicate?
Blood contamination
Outline the major calf factors that prevent adequate colostrum ingestion…
Weakness
Acidosis
Dystocia
Mouth problems
Outline the major udder factors that prevent adequate colostrum ingestion…
Sore teats
Teat shape
Teat alignment
Dropped udder
Outline the major maternal factors that prevent adequate colostrum ingestion…
Poor mothering Disturbances/stress Overcrowding Caesarean section Milk fever Slippery floors
Outline available methods to ensure a calf has adequate colostrum intake…
Assisted suckling
Bottle and teat
Oesophageal feeder
For how long must a calf suckle to ingest 2L of colostrum?
20-30 minutes
Outline how colostrum absorption efficiency changes in the hours following calving…
6 hours: 66%
12 hours: 46%
24 hours: 12%
36 hours: 7%
How do herbivores receive maternally-derived antibodies?
Colostrum only
How can you improve the quality of colostrum?
Vaccination of dam (e.g. rotavirus)
Store colostrum and allow it to ferment
- Feed stored colostrum over several days for effective mucosal protection
How is colostrum quality assessed?
Measure IgG
Specific gravity
Refractometer
