Farm animal neonatal disease Flashcards
Role - colostrum
- IMMUNE: primary protection vs neonatal septicaemia and joint/ navel ill, protect vs enteropathogens, protect against enzootic pneumonia
- NUTRITION: first feed, with additional vitamins and trace elements
What % calves die?
8.8% (i.e. 176,000 calves)
Main causes death in calves - 3
- diarrhoea
- pneumonia
- FPT
Phsyiology - colostrum
4-6 wks before calving there is Ig transfer into udder, IgG1 is actively transferred to colostrum, following ingestion of colostrum by calf, Ig is absorbed by epithelial cells of SI and passes via lymphatics to peripheral blood circulation
Outline the systemic and local protection that colostrum offers
- SYSTEMIC: with IgG1 and IgM
- LOCAL protection of GIT: re-secretion of IgG1 into GIT lumen, passage of IgA in colostrum/ milk through gut lumen
How much IgG1 is needed?
- 5g/L in plasma (protection)
- 10g/L in plasma (no dz)
What is the dz triad?
- immunity
- agents
- environment
How much blood is in the average mammal?
8% BWt
What factors influence uptake?
- first milking: rapid decrease after each milking
- milk yield: only 29% holsteins have 100g Ig in 2 L of colostrum
- dairy vs beef
- pre-calving milking or leaking of milk
- short dry period
- premature calving/ abortion
- heifers vs cows (heifers have reduced milk yield thus increased concentration but pathogens that Ab covers are less varied as less exposure d/t younger age)
What are the 3Qs?
Regards colostrum: quality, quantity, quick
Are beef and sheep young able to suckle to get sufficient colostrum?
usually ok because need a small volue of concentrated colostrum
Are dairy young able to suckle to get sufficient colostrum?
often rely on suckling but probably not best:-
- 2L at first feed traditional
- 3-4L for 45kg calf from holstein dam more effective
What 3 main factors affect the volume of colostrum a calf sucks?
- CALF (weak, acidosis, dystocia, mouth problem e.g. tongues of belgian blues being double mm)
- UDDER (sore teats, teat alignment, teat shape/size, dropped udder)
- MOTHER: poor mothering, heifers, disturbance/ stress, overcrowing of calving area, c-section, milk fever/ downer cow, slippery floors
How do you ensure a calf gets enough colostrum?
- assisted suckling (20-30 mins continuous suckling to ingest 2L)
- bottle and teat and patience!
- oesophageal feeder 3-4L (Not a stomach tube!)
What does closure of gut wall depend on?
- presence of protein in GIT (negative feedback loop: presence of proteins causes gut wall closure)
- time after calving
What is one of the most important risk factors for hypogammaglobulinaemia?
delay in suckling
What determines colostrum quality?
- exposure of dams to pathogens
- vaccination (e.g. rotavirus): store colostrum and allow it to ferment, feed stored colostrum for several days (IgA)
How do you assess colostrum quality?
- IgG cut-off point of 50g/L
- Specific gravity (good if >1.048): use hygrometer, cave: temperature sensitive
- Brix refractometer: aim for > 22%
- thicker the better
How do you assess colostrum UPTAKE?
CALF SERUM:
- IgG of >10g/L
- gammaGT (200IU/L on day 1, 100IU/L on day 4)
- TP > 55g/L (some argue > 60g/L)
- Zinc sulplate test = ZST (>20g/L)
- Sodium sulphite >18g/L solution
What if colostrum managment fails?
- feed stored colostrum OR
- feed a commercial colostrum supplement
How long can colostrum be stored?
- 15 degrees = 24 hrs
- 4 degress = 7 days
- 20 degrees = 60 months +
How to thaw colostrum
thaw at room temperature so proteins and enzymes and immunoglobulins etc aren’t destroyed