Calf Diarrhoea Flashcards
Name the 5 main agents that cause diarrhoea in calves
- Rotavirus
- Coronavirus
- Cryptosporidium
- E.coli
- Salmonella
At what age do calves start to have diarrhoea and why?
At one week old
Almost all calves start excreting bugs
What is the MOA of Rotavirus and coronavirus, what are the consequences of this for the calves?
Damage to intestinal lining
→ Malabsorption of milk → Fluid and electrolyte loss → dehydration, acidosis, death
When does peak shedding of Salmonella occur?
Following stressors e.g. calving
Describe the signs of a salmonella infection
Diarrhoea +/- mucous casts, dysentery, pyrexia, joint infections, abortion, pneumonia, sudden death following septicaemia
What are the sources of diarrhoea agents for calves?
- Adult cows: low doses “seeding”
- Other calves - pathogen multipliers = Healthy (older calves), diarrhoeic and recovered
- Environment
Describe passive immunity as a host defence mechanism
Local IgG and IgA adhering to mucosal surface. Derived from colostrum.
From first feed
Continued intake
Hoe else can host defences help in diarrhoea cases?
Healthy gut flora - suppresses growth of pathogens - “competitive inhibition”
Healthy mucosa – nutrition
Describe the importance of the 1st colostrum feed
- “medical colostrum”
- Ig absorbed
- Re-secretion of Ig for 5-7 days –> protection
Calve protection after 5-7 days depends on?
- “tonic colostrum”
- Continued intake of Ig rich milk/colostrum
- So .. continue feeding “transition milk for – 4 -7 days e.g. 1+ litre daily with milk replacer
How can the environment influence diarrhoea in calves?
- Pathogen load
- Inside vs outside
- Single vs group housing
- Hygiene
- Cleaning protocols
How can the timing of a calf being born influence its likeliness of a diarrhoea infection?
“build-up” of bugs in environment
e.g. 15 w calving period –
Risk of death was X10 for calves born in last part of season compared to calves born in first half.
In a scour outbreak investigation what questions might you have about calf nutrition?
Did they receive colostrum? Feeding schedule? Transitional milk? Timing of colostrum? Which milk replacer?
How can a milk replacer influence a calf diet?
If too concentrated when mixed up it can cause dehydration due to nutritional scours: lower in fat and protein than regular milk but higher in lactose
How can calf scours be prevented?
Minimise exposure
Maximise protection
Minimise stress
How can exposure be minimised in dairy calves?
- Clean calving area
- “snatch calve” – remove calf within 2-4 hours of birth
- Clean calf housing
- Hygiene – at feeding
- Hospitalise sick calves
How can exposure be minimised in beef suckler calves?
Calve outside: - Tight calving period - flow system - “Sandhills system” Hospitalise sick calves: - Do not return to group “at risk”
How can protection of calves be maximised on a dairy farm?
- 5-10% of BW (2-3 litres) colostrum within 2 hours, repeat in 6 to 12 hours
- **continue colostrum feeding for 4-10d ‘tonic’
How can protection of calves be maximised on a beef farm?
- Adequate cow nutrition
- Feed for 3 weeks pre-calving - protein
- Frozen colostrum e.g. after bad calving
- Vaccinate dam (e.g. Rotavec)
In a scour outbreak investigation what questions might you have about the cow management?
Vaccination Nutrition Length of dry period Disease Indoor/outdoor Cleaning routine
Describe vaccination of dams for calf protection
- Vaccinate dam ~ 30 days before calving.
- Need to know ~ calving date.
- Works via colostrum / milk.
- Boost milk IgG and IgA levels for 21 days
The Sandhills system for beef cattle reduces?
Contact between young & older calves
Build up of pathogens
“eliminates pathogen multiplier effect” - eliminating scours
In the Sandhills system, when are groups comingled?
After the youngest calf in a group is 4 weeks old
Why can we not use the Sandhills system in the UK?
Sandhills is not feasible if calving indoors (would need a large barn!)
