Pre-harvest risk factors

Question 1

What are the 5 main principles and control measures for meat safety at pre harvest phase

Answer 1

1. Prevention of recycling pathogens in the environment
2. Prevention of introduction or spread of pathogens with the farm
3. Prevention of ingestion of pathogen by animals
4. Suppression of ingested pathogen within GI tract
5. Enhancement of animal host response

Question 2

Give some pre-harvest control measures which coincide with the main principles

Answer 2

• Biosecurity
• Hygienic husbandry
• Feed and water treatments
• Diets
• Probiotics and prebiotics
• Vaccination
• Reduce stress
• Genotype resistance

Question 3

Which pathogen is of most concern in processed foods?

Answer 3

Listeria monocytogenes

Question 4

Which pathogens are of most concern in raw foods?

Answer 4

Campylobacter
Salmonella enterica
Escherichia coli

Question 5

What makes up the pre harvest phase?

Answer 5

Birth, weaning, life on farm

Question 6

What makes up the harvest phase?

Answer 6

Lairage
Stun/bleed
Skin, dehair, pluck
Chill and dispatch

Question 7

What makes up the post-harvest phase?

Answer 7

Meat cutting
Meat processing
Retail
Consumers

Question 8

What animal is considered to be the main reservoir of Escherichia coli?

Answer 8

Cattle

Question 9

How can recycling of pathogens in the environment be prevented?

Answer 9

Effective land management

Effective vector controls

Question 10

Give some examples of hygienic animal husbandry

Answer 10

Effective cleaning regimes
All in all out farming systems
Animal cleanliness

Question 11

How can ingestion of the pathogen be prevented?

Answer 11

Feed control
Water sanitation
Reduction of animal interactions - sucking, licking, oral secretions, separate calves from adults, maintain stable groups

Question 12

How can the pathogen be supressed in the GIT?

Answer 12

• Dietary manipulation
• Probiotics: competitive exclusion
• Prebiotics to enhance the normal gut flora, should not be digestible by the body

Question 13

What are the 2 main methods of enhancing the hosts reponse?

Answer 13

Vaccination

Stress management

Question 14

How should cattle be prepared for salughter?

Answer 14

Finish with a well balanced diet
Housing - slatted yards, correct stocking rate, clean bedding
Feed withdrawal 12 hrs before to reduce GI contents to prevent rupture and carcass contamination

Question 15

How is stress a risk factor in the slaughter phase?

Answer 15

• Increased defecation
• Increased shedding of bacterial pathogens
• Weakened immune response

Question 16

What other risk factors are present in the slaughter phase?

Answer 16

Mixing animals of different origin
Animal activities and interactions
Prolonged transport
Previous vehicle contamination