Dr. Paul KitchingChief Provincial Veterinarian

Director Animal Health BranchBC Ministry of Agriculture and Lands

October 22, 2009

Overview of meat, milk, egg production in BC

Enteric pathogens– are they the same for animals and humans?

Case studies: E.coli O:157 and SE On farm measures to reduce pathogens Summary

Supply managed (quota system) : $1.6 billion; 28,000 jobs

◦ Table eggs◦ Chicken meat/products◦ Turkey meat◦ Milk / Dairy

Other◦ Beef (cow/calf

ranching, feedlots)◦ Pork (swine operations)

•Large part of BC economy:•Subject to total devastation during animal disease crisis. • Small scale production occurs especially in rural areas

4086 beef cattle ranches in BC

-598,500 cattle (Bulls, Cows, Calves, Steers, & Heifers) (4.3% of Canadian herd)

-269,325,000 lbs. of beef produced annually

British Columbia Beef Consumption /year = 207,916,000 lbs. [Avg 47.2lbs of beef consumed per person annually (Statistics Canada 2008)]

Export market for British Columbia’s Cattle & Beef

31 registered swine production farms in BC

> 200,000 market hogs / year

Most of the pork consumed in BC is imported from other provinces and US

Is it Safe? Influenza in swine herds is

reportable to CVO- no cases have been reported since 2008.

June 2009: WHO/ OIE/ FAO- The risk of being infected with

swine influenza viruses through the consumption of pork or pork products is negligible.

Influenza viruses are generally restricted to the respiratory tract of pigs and are not detected in the muscle (meat) of pigs, even during acute illness.

Approx. 560 dairy farms ◦ 67% Fraser valley◦ 17% OK◦ 10% VI◦ Caribou, Kootneys, Peace

652,231,187 total litres of milk produced /year August 2007-July 2008

Routine sanitation practices:◦ Cleaning and flushing milk

machines◦ Sanitize and dry teat

before milking◦ Separate animals with

mastitis – milk not added to bulk tank

◦ Manure, feed, housing management

◦ Bacterial cell count on every tank

◦ PASTUERIZATION!

325 chicken farms in BC produce about 158 million kilograms of meat /year

64 turkey farms in BC produce about 21.3 million kilograms of meat

129 table egg farms in BC produce about 61.8 million dozen eggs

Ref: http://www.bcegg.com/files/documents/BACKGROUNDERBCDEPIsocioeconomicimpactstudy.pdf

Animals are not sterile.The environment is not sterile.

Foods without bacterial kill steps (pasteurization, irradiation, thorough cooking)can have risks

Animal reservoir◦ Campylobacter (poultry)◦ Salmonella spp. (poultry, cattle, reptiles, wildlife

etc)◦ E. coli 0157:H7 (ruminants- esp. cattle, deer) ◦ Cryptosporidium (young calves, wildlife)◦ Giardia (wildlife, humans, animals)◦ Yersinia psuedotuberculosis and enterocolitica

(wildlife, birds, pigs)

Human reservoir: i.e. Norovirus, Shigella

Enteric pathogens: ingestion◦ Usually fecal- oral

contamination Animal to animal [Environment] Animal to human

◦ Some pathogens can contaminate the product Eggs: Salmonella enteriditis

ENVIRONMENT

ANIMAL

HUMAN

AGENT

Poultry Salmonella pullorum Salmonella

gallinarium

Mammals

Humans Salmonellosis (all

serotypes) Campylobacterosis Verotoxigenic E. Coli Cryptosporidiosis Yersiniosis

Contamination can occur at several points along the food chain◦ On the farm ◦ Irrigation of crops ◦ At the slaughter plant◦ During processing◦ At the point of sale◦ During preparation

E.Coli O157 :H7 are intestinal bacterial flora of ruminant animals, including cattle, goats, sheep, deer, and elk.

A major source of human illnesses is consumption of undercooked ground beef.

E.Coli O157 :H7 that cause human illness generally do not make animals sick.

Other kinds of animals, including pigs, small mammals, and birds, sometimes pick up E.Coli O157 :H7 from the environment and may spread it.

Cattle are primary reservoir:large intestine, recto-anal junction• warm, constant• nutrient rich• vigorous growth

Environmental spread: water, soil, sediment• cool, fluctuating• nutrient limiting• survival

Excretion

Re-colonization

Environment

E.Coli O157 :H7

•Cattle are asymptomatically colonized- transient and common intestinal flora

•Seasonal- summer peak, winter nadir

•Endemic and fluctuating populations- feedlot, pen, farm, week

•Intermittent isolation - feces, hide, oral cavity

E.Coli O157 :H7 on Farms

Systematic Review done in 2007 by PHAC and McMaster U

Interventions:◦ Probiotics◦ Vaccination (new

product)◦ Antimicrobials

Results: Evidence of efficacy Probiotics

◦ L. acidophilus NP51 + P. Freudenreichii

◦ Sodium chlorate Vaccination- not consistent Antimicrobials – no

evidence to support use for this purpose

Sargeant et al. Pre-harvest Interventions to Reduce Shedding of E.coli O157 in the faeces of weaned domestic ruminants: Systematic Review Zoonoses and Public Health 2007; 54(6-7):260-77

More than 2000 serotypes About 30 are very common in

poultry, others are found in cattle, reptiles, etc.

Salmonella spp. are primarily intestinal flora

Salmonella spp. generally do not cause disease in reservoir hosts: poultry, adult cattle, reptiles but can cause disease in horses, pets, humans and many other animals.

S. Enterditis invades hens reproductive tract leading to contamination of the egg.

SE is well adapted to rodents and chickens Easily transferred from hen to chick and

environment Transmitted to humans during consumption

of undercooked eggs

Routine Testing for Salmonella enterditis◦ Identify infected flocks: Swab and culture environment◦ Control: divert eggs/depopulate/clean premise

Vaccination-◦ Varying effectiveness

Control of rodents, wild birds- very important Purchase feed from supplier (CFIA tested) All in/all out- no mixed ages, periodic empty

premise Regular thorough cleaning and disinfection of

premises Start with SE free birds

Probiotics

Management and judicious use of veterinary drugs:◦ Withdrawal times for milking and meat animals

(according to known breakdown and excretion of the drug)

◦ Controversy about antimicrobials used for prevention

Mandatory in regulated poultry industry In development for swine Purpose: reduce risk of infectious disease transmission

within and among flocks, animals. Components:

◦ Farm Access Standards (roads and gates, signage, vehicle decontamination)

◦ Barn Access Standards (anteroom, restricted access)◦ Flock Health Management (records, recognizing illness,

introduction of new animals, diagnostic sampling, mortality, disposal)

◦ Farm Management (manure, pest control, cleaning/decontamination, producer and employee training, SOP’s ,visitor log)

Production programs based on HACCP principles:◦ Beef: Quality Starts Here and Verified Beef

Production◦ Chicken: Safe, Safer, Safest (On Farm Food

Safety Assurance Program)◦ Eggs: Start Clean- Stay Clean◦ Milk: Canadian Quality Milk Program

Ongoing effort to improve disease detection in small flocks via training of veterinarians and seminars for small flock owners

BC Good Agricultural Practices manual◦ Target audience:

unregulated farmers◦ Avoids technical terminology ◦ HACCP based format◦ Assessment flow

chartsdetermine GAPs implementation tools (who, what, where, how)

Post harvest Strategies:◦ Pasteurization- (kill step) ◦ Grading- Eggs◦ Meat inspection at slaughter◦ Refrigeration◦ HACCP programs in processing◦ Irradiation (kill step) proper storage, handling, prep, cooking..

On farm strategies can reduce but not eliminate pathogens

Some pathogen monitoring and control programs in place: Milk- somatic cells, antibiotics; Egg- SE

Research being done to develop and evaluate more effective farm level interventions and vaccines

Increasing practice of biosecurity and on-farm food safety programs and standards

Provincial /Local foods: Chicken, turkey, milk and eggs produced in BC are consumed in BC

There is no food safety risk associated with influenza in pigs

Questions?