24 terms

VPH - 12. Farm assurance schemes

What effects did BSE have on farming?
Collapse of export market
Reduced value & prices for meat
Reduced beef production in UK
More imports of beef
Some of these effects related to global over-production of beef
What indirect effects did BSE have on livestock farming?
Changes in livestock production systems - couldn't consume animals >31mo
Growth of alternative farming systems - e.g. Organic
Farm assurance & product certification
Development of the precautionary principle & extension of HACCP into food production
How was consumer confidence restored after BSE?
Eradication of the disease - no live tests
Compliance with regulation
Increased enforcement & auditing
Assurance of production method
Industry self-regulation
How long is the incubation period for BSE?
Approx 5yrs
What was the source of BSE infection?
Feed contaminated with MBM = rich source of transmission

Cohorts affected as consuming same batch of food

No horizontal transmission

Vertical transmission in later stages of dz
Why is BSE a problem?
Able to cross species barrier?

Cases in domestic cats
Humans - nVCJD
Zoo animals
Potential zoonotic dz

Massive impacts on trade between countries

V low incidence in most countries - not a problem for farmer - but huge impact on industry
When was BSE first identified in the UK and how did it spread?

Infected cows entered animal and human food chain - recycling of BSE cattle to cattle fuelled outbreak

Rapidly spread to national outbreak of 200,000 cases

Spread to other countries by export of infected MBM or cattle incubating dz
How were cattle infected and what is the pathogenesis?
Oral ingestion of contaminated feed

Enters lymphoid tissue - affects brain

Clinical dz - approx 5yrs after exposure
Which are the high risk tissues for exposure to BSE?
Lymphoid tissues
Spinal cord
How was BSE controlled?
Cattle - prevent consumption of BSE infected material in food

Humans - prevent consumption of BSE infected cattle and/or high risk tissues
When did BSE become notifiable?
Which control measures were introduced in 1988 ?
1. Ruminant feed ban to prevent recycling of dz in cattle population - July 1988
2. Notifiable dz
3. Diseased animals couldn't enter food chain
4. 50% compensation paid to farmers for clinical cases for first 18 mths

Aim = to control rising incidence in cattle population
Why wasn't the ruminant feed ban fully effective?
V small infective dose

Cross contamination in feed mills as RMBM still in pig feed

Farmers fed food destined for other species to cattle - e.g. leftover chicken feed

No recall of existing food from prior to ban - stockpiles still fed to cows

Low compensation for farmers - off to slaughter with early clinical signs
New control measures
1. Removal of specified offals and high risk material from animal/human food chain
2. Staining of offal with methylene blue to ensure not entering food chain
3. Tightening of meat inspection
4. Rigorous auditing of key control point by FSA
When was the ruminant MBM introduced in the EU?
Lessons learnt from BSE
1. Just because you make a rule - doesn't mean it will be complied with all the time
2. Auditing of controls = as important as creating the rule
3. BSE = highly infective if fed to cattle in feed
4. Higher compensation improves reporting
5. Vets, farmers & feed mills should have been involved from the start
Summarise the BSE control measures in the UK by year
1988 - no ruminant feed to ruminants & removal of suspect cows - became notifiable

1989 - removal of high risk material from human food chain

1990 - removal of high risk material from animal food chain

1996 - no feeding of mammalian protein to farmed livestock

1996-2004 - no human consumption of cattle over 30 months of age
How did BSE surveillance change in 2013?
No longer testing carcases of healthy animals

Testing restricted to fallen stock over 48 months = surveillance tool
What were the positive outcomes of the BSE outbreak?
1. Cleaned up meat production industry
2. Made producers aware of responsibilities & consumer demands
3. Created national database & cattle identification system BCMS
4. Farm assurance schemes & consumer awareness
5. Proved importance of legislation with enforcement
When was the BPEX-ZNCP initiated for Salmonella in pigs?
How does it work?
Antibody testing for Salmonella on tissue samples from abattoir

Farms graded on incidence - e.g. platinum <10% test positive

Action plan implemented if 50% or more test positive
How many samples are taken for the Salmonella ZAP programme introduced in 2002?
Initially 1:50 pigs sampled

From July 2003 - 3 per batch

From 2007 - 15 samples per quarter

Voluntary sampling by abattoirs
Where are these samples taken from?
Diaphragm & neck muscle
When did ZNCPig replace ZAP?
April 2008

4 meat juice samples per month from sites supplying finishing pigs

All herds must have a salmonella control plan - reviewed annually, must show progress

No categorisation

Recognition for best practice if <10% of samples = positive


Replaced by farm and abattoir risk assessment tools