News from the National Pork Board

PQA Plus update

The Pork Quality Assurance Plus (PQA Plus) program was officially introduced to US pork producers at the World Pork Expo in Des Moines, Iowa, on June 7. Several National Pork Board members and members of the Pork Checkoff’s Pork Leadership Academy were among the first producers to be certified in the new program.

The program combines pork safety elements from the Pork Quality Assurance program and animal care and well-being principles from the Swine Welfare Assurance Program. Responsible antibiotic use principles and guidelines from the industry’s Take Care, Use Antibiotics Responsibly program also are part of the new PQA Plus.

“The pork industry is working on programs that will demonstrate to our customers accountability, trust, and social responsibility in pork production,” said Wayne Peugh, pork producer from Edelstein, Illinois, and the National Pork Board’s president. The National Pork Board identified image as one of the critical issues the industry faces with its customers today. “With PQA Plus, pork producers can demonstrate their commitment to producing a safe product and their commitment to sound animal care practices.”

The program is a continuous-improvement system focused on producer education, producer certification, and premises assessment. An audit of a representative sample of sites will extend credibility to the program.

In addition to pork producers’ willingness to adopt PQA Plus, acceptance by the pork industry is critical. In a news conference during the World Pork Expo, Dr Daryl Olsen of the AASV said, “The AASV is very pleased to support the new PQA Plus program. Practitioners and producers will continue to rely on the framework provided by the new PQA Plus program in maintaining high standards for judicious antibiotic use, residue avoidance, health management, and welfare assurance.”

A nationwide network of trained and certified advisors is available to work with pork producers to help them achieve PQA Plus certification. As with PQA Level III certification, PQA Plus certification is valid for 3 years. Producers currently certified in PQA Level III will continue to be certified until their current certification expires. For information on the availability of advisors in a certain area or on how to become an advisor, call the Pork Checkoff Service Center at 800-456-PORK. Additional information also is available at www.pork.org/Producers/PQA/PQAPlus.aspx.

More information on the PQA Plus program is available online at www.pork.org or by contacting the Pork Checkoff at 800-456-PORK.

Nutritional efficiency consortium and call for proposals

The Pork Checkoff is working to address the effects of rising corn prices on pork producers. In February, the National Pork Board approved $400,000 for the development of a nutritional efficiency research and education consortium, bringing together organizations throughout the pork industry and agriculture.

The objectives of the nutritional efficiency consortium include:

• To maximize production efficiencies through improved feed conversion and reduced or optimized feed costs.

• To help producers lower feed costs through improved feeding technologies and information about the use of lower-cost alternative diet components.

• To develop comprehensive research programs to address genomic and cellular-level nutrient utilization processes and capabilities.

• To develop real-time decision-making tools to evaluate the opportunities and challenges created by corn and other ingredient prices and co-product availability.

The Pork Checkoff has received support from several state pork associations and private organizations and has, to date, matched the initial funds provided by Checkoff funds.

Participants in the consortium include: Arizona Pork Council, Illinois Pork Producers Association, Iowa Pork Producers Association, Kansas Pork Association, Mississippi Pork Association, Missouri Pork Producers Association, Nebraska Pork Producers Association Inc, North Carolina Pork Council Inc, Utah Pork Producers Association, Montana Pork Producers Council, National Corn Growers Association, DPI Global, Elanco, JBS United, Lucta SA, and Pioneer Hi-Bred.

The consortium has worked together to develop the research and education priorities. Initial calls for proposals were posted online in the spring with a due date of June 18. Funding and research resulting from this call is scheduled to begin in the summer of 2007.

Calls for research proposals in the areas of swine health and pork safety

In early June, the National Pork Board posted requests for research proposals in the areas of swine health, focusing specifically on porcine circovirus associated disease (PCVAD) and pork safety. Selected projects will be funded in the summer of 2007. The deadline for submission of proposals was July 10.

Research priorities for the PCVAD call

1. Immunology

a. Determine the role of cell-mediated immunity and humoral immunity in the immune response to PCV2a and PCV2b infection.

i. Defective immune response.

ii. Effective immune response.

b. Investigate the effect of strain variation on cross-protection and on cell-mediated immunity and humoral immunity.

c. Determine cross-protection and whether immunogenic epitopes need to be conserved among different strains.

2. Epidemiology

a. Determine the predominant mode of transmission.

b. Investigate and identify factors influencing transmission: virus type, pig genetics, herd size, and production system (number of sites).

c. Molecular epidemiology: establish a PCV2-sequence database that links strain sequence with clinical disease, infectious co-factors, management practices, chronology, and geographic locale.

i. Investigate the amount of genetic variation there is within a genotype.

ii. Determine whether that genetic variation is also reflected as antigenic variation.

d. Develop checklists of risk factors, management approaches, and roles of other agents, cofactors, and serum therapy.

e. Evaluate current practices:

i. Evaluate what biosecurity practices may prevent infecting a herd.

ii. Evaluate whether injections with antibiotics, vaccines, and serum therapy transmit disease.

f. Estimate whether susceptibility, transmissibility and persistence change with age, PCV2 strain, various co-factors, and management factors.

g. Define the role of the sow herd in an outbreak:

i. In a cleanup program.

ii. Identify the criteria for determining when an unaffected farm should begin vaccination (geospatial factors, when undertaking “risky” practices, cost-benefit in an unaffected farm).

h. Define the duration of PCV2a and PCV2b infection and the ability to be transmitted when:

i. Young pigs are infected.

ii. Older pigs are infected.

3. Pathogenesis

a. Develop tools for pathogenesis research, including source of PCV1-negative and PCV2-negative pigs (all ages), reproducible disease model, and technology to look for other agents.

b. Conduct classical pathogenesis studies in conventional pigs to investigate:

i. Role of PCV2a and PCV2b in PCVAD: determine which genotype is more strongly associated with PCVAD.

ii. Role of concurrent PCV2a and PCV2b infections: determine whether dual genotype infection results in more severe disease than infection with a single genotype.

c. Determine variability in disease expression due to host variation, ie, genotype-phenotype, age-parity, management, and gender.

d. Determine the role of PCV2 in vertical transmission:

i. The frequency of vertical transmission.

ii. Whether vertical transmission is constant or changing as a function of the PCV2 genotype and antibody status of the breeding herd.

iii. Semen transmission in PCVAD: viral loads and frequency and identification of contaminated semen.

iv. Effect of sow or gilt exposure to PCV2.

e. Characterize diseases caused by PCV2 and selected co-factors: Does co-infection with specific co-factors result in a specific disease syndrome?

i. PCVAD model systems to investigate include PDNS, shaker pigs, PRDC, and PMWS.

ii. Agents to investigate include PCV2a and PCV2b, PRRSV, teschovirus, parvovirus, and others.

4. Diagnostics

a. Develop standardized diagnostic tools for use in diagnostic laboratories in North America. Tools and tests include:

i. Tissue-culture-adapted PCV2a and PCV2b.

ii. Monospecific polyclonal and monoclonal antibody.

iii. Standardized differential and real-time PCR.

iv. Standardized IFA and serum neutralization serology.

v. Quantitative DIVIA-antibody ELISA.

b. Determine when pigs stop shedding, especially focusing on detecting the carrier state in gilts and boars.

c. Develop protocols for monitoring boar studs and breeding herds, especially for the purpose of producer surveillance and import criteria.

d. Define and quantify serological profiles to address clinical expectation by investigating timing of infections and vaccinations.

5. Prevention and treatment

a. Investigate the relationship of maternal (passive) antibody and:

i. Vaccination interference: Determine whether high levels of maternal antibody interfere with vaccination.

ii. Investigate the amount of antibody variation existing in the breeding herd and how this might impact maternal antibody transfer:

• Determine whether that variation is a function of parity.

• Determine whether it would be beneficial to have the same level of antibody in the breeding herd.

iii. Cross-serotype or cross-genotype infection: Investigate whether maternal antibody has the same “protective” effect on PCV2a and PCV2b (ie, does one virus get in and infect baby pigs sooner than the other in pigs that have the same levels of passive antibody).

iv. Determine whether passive antibody against one genotype promotes infection at a younger age with the other genotype.

b. Vaccine composition: Determine whether a PCV2b-based vaccine is better than a PCV2a-based vaccine in the face of PCV2b infection.

c. Determine vaccine efficacy in the face of PCV2 and cofactors.

d. Determine the most effective truck and facility decontamination procedures to reduce or eliminate PCV2 from the environment.

e. Investigate ability to produce PCV2-negative pigs from positive herds. If possible, determine ramification of repopulating with PCV2-negative pigs.

Call for proposals on pork safety

1. Pre-harvest reduction of pathogens with potential public health significance.

Pre-harvest food-safety research included the areas of epidemiology, pathogenesis, prevalence, on-farm risk-factor management, and monitoring and measurement or intervention and control strategies or both, with a priority on Salmonella. Specific topics of interest included:

a. Development and evaluation of enumerating salmonellae before and after interventions to determine their effectiveness.

b. Development of a risk-assessment model to quantify the relationship between on-farm prevalence of Salmonella and other zoonotic pathogens and the risk of human illness.

c. Development and evaluation of evolving molecular and other diagnostic tools and monitoring techniques that can be used in epidemiological investigations.

d. Development of strategies for data collection and data management to predict the need for application of interventions to reduce Salmonella prevalence to an acceptable level.

e. Test the impact of Salmonella lairage reduction programs on the amount of Salmonella contamination found on the carcass or in the final product.

f. Evaluation of dietary characteristics (eg, feed form, dietary ingredients, antibiotic use, feed contamination levels) as a potential intervention strategy to reduce Salmonella prevalence.

g. Study transmission rate of Salmonella within production systems or barns and by serotype or genotype.

Specific topics of interest with regard to Toxoplasma gondii, Campylobacter species, and Yersinia enterocolitica included:

a. Development of management or facility strategies or both for outdoor or bedded pigs to reduce the risk of these pathogens.

b. Identification of previously unrecognized risk factors for infection with these pathogens, and interventions to address those risks.

c. Controlled studies to determine the relative contribution of water sources on these pathogen infections in swine and effective interventions at the producer level.

2. Post-harvest reduction of pathogens with potential public health significance.

Priority was again placed on Salmonella research. Specific topics of interest included:

a. Development and evaluation of enumerating salmonellae before and after interventions to determine their effectiveness.

b. Studies to increase the knowledge base of multi-drug-resistant bacteria in pork and to determine their susceptibility to microbiological interventions.

c. Expand knowledge of stress adaptation and cross-protection of pathogens.

d. Identification of sanitation procedures capable of preventing cross-contamination with allergens.

3. Impact of production practices on carcass defects and physical hazards.

Research should include the areas of epidemiology, pathogenesis, prevalence, risk-factor management, monitoring and measurement or intervention and control strategies or both, including:

a. Studies to determine the impact of alternate injection methods or techniques (such as hip injection or needle-free injection systems) on carcass defects, physical hazards, or both.

b. Studies to determine the causes of, and farm-level interventions for, carcass defects such as abscesses, physical hazards, or both.