The minutes of the AASV Board of Directors meeting held March 5, 2005 in Toronto, Ontario have been posted on the AASV website at http://www.aasv.org/members/only/board/index.htm. Access is limited to AASV members (username and password required).
Monthly Archives: March 2005
AASV invites members to comment on Boar Stud Guidelines
The AASV Boar Stud Committee is reviewing the document “Health, Hygiene, and Sanitation Guidelines for Boar Studs Providing Semen to the Domestic Market” for potential revision. The committee invites AASV members to submit their comments via a web-based form available at http://www.aasv.org/members/only/BoarStudComments.php (AASV username and password required for access). The easy-to-use form allows members to view the document and enter comments and suggestions – either within the document text itself or as stand-alone remarks – for consideration by the committee. Comments may be submitted anonymously if desired.
PRRSV Research Funding ? New Requests for Proposals
National Pork Board and the North-Central 229 PRRS Integrated Program Project on PRRS Elimination are seeking research PRRSV research proposals. These two efforts awarded nearly $3.5 million in PRRSV-related research grants in 2004 and anticipate similar funding levels for 2005.
Influence of Farm size on the prevalence of gastric lesions in slaughter pigs in Spain
A study was conducted to determine and compare the prevalence of gastric lesions in slaughter pigs raised on farms of varying sizes in Spain. A total of 20,796 pig stomachs were evaluated in this study by veterinarians at the slaughter plant. Finishing pigs used in this study were slaughtered at the same slaughter plant and during the same week. Pigs originated from 129 different farms in the Southeast of Spain. Animal transport to the slaughter plants was less than 150 km for all farms and all pigs were allowed a rest period of 4 to 8 hours following transport. Stomachs that were observed on the slaughter line were categorized as either having gastric lesions and further categorized to whether or not these lesions were ulcerated. Producers from which the pigs originated were categorized by their size using the following criteria: “small producers” were defined as having less than 10,000 finishing pigs simultaneously, “medium producers” having between 10,000 and 50,000 finishing pigs simultaneously, and “large producers” having greater than 50,000 finishing pigs.
Research Shows Improved Handling Reduces Stress Induced Death Loss
Dr. Harold Gonyou is the Research Scientist in Applied Ethology at the Prairie Swine Center in Saskatchewan, Canada. Recent research conducted at the Prairie Swine Center has demonstrated that improved handling of pigs during loading and transport can quite dramatically reduce stress in the pigs.
Position Announcement: Manager, Veterinary Medicine Biological Clinical Development
Pfizer Inc, a Fortune 100 multinational human and animal health care corporation, has a challenging opportunity at its Lincoln, Nebraska facility for a Manager, Veterinary Medicine Biological Clinical Development.
Seroprevalence of Noroviruses in Swine
Abstract: Noroviruses (NVs) are important human pathogens that cause acute gastroenteritis. Genetically related animal enteric NVs have also been described, but there is no evidence of interspecies transmission of NVs. In this study we characterized antibody prevalence among domestic pigs by using recombinant capsid antigens of two human NVs (Norwalk and Hawaii) and one swine NV (SW918) that is genetically related to GII human NVs. Recombinant SW918 capsid protein expressed in baculovirus self-assembled into virus-like particles (VLPs) that were detected by antibodies against GII (Hawaii and Mexico), but not GI (Norwalk and VA115), human NVs. NVs recognize human histo-blood group antigens as receptors, but SW918 VLPs did not bind to human saliva samples with major histo-blood group types. Seventy-eight of 110 (71%) pig serum samples from the United States and 95 of 266 (36%) pig serum samples from Japan possessed antibodies against SW918. Serum samples from pigs in the United States were also tested for antibodies against human NVs; 63% were positive for Norwalk virus (GI) and 52% for Hawaii virus (GII). These results indicate that NV infections are common among domestic pigs; the finding of antigenic relationships between SW918 and human NVs and the detection of antibodies against both GI and GII human NVs in domestic animals highlights the importance of further studies on NV gastroenteritis as a possible zoonotic disease.
Livestock Stress Research at ARS
Agricultural Research Service (ARS) scientists are working in collaboration with an animal behaviorist from Purdue University, Dr. Ed Pajor, to investigate the impact of current livestock production practices on animals’ stress levels. They are designing research protocols to evaluate an animal’s preferences regarding socialization. The initial research has allowed sows in gestation stalls to choose between additional food rewards or opportunities to socialize with their neighbors. The current results seem to imply that sows do not exhibit a preference for socialization over food. Additional trials are being designed to evaluate a preference for “enhanced” environmental conditions such as softer flooring or the presence of nesting materials.
Effect of avilamycin on antimicrobial resistance in enteric bacteria in the pig
Aim: To assess the effect of the growth promoter avilamycin on emergence and persistence of resistance in enteric bacteria in the pig. Methods and Results: Pigs (treated with avilamycin for 3 months and controls) were challenged with multi-resistant Salmonella enterica Typhimurium DT104 and faecal counts were performed for enterococci, Escherichia coli, S. Typhimurium and Campylobacter (before, during and 5 weeks post-treatment). Representative isolates were tested for antibiotic resistance and for the presence of resistance genes. Avilamycin-resistant Enterococci faecalis (speciated by PCR) were isolated from the treated pigs and continued to be detected for the first week after treatment had ceased. The avilamycin-resistance gene was characterized by PCR as the emtA gene and speciation by PCR. MIC profiling confirmed that more than one strain of E. faecalis carried this gene. There was no evidence of increased antimicrobial resistance in the E. coli, Salmonella and Campylobacter populations, although there was a higher incidence of tetB positive E. coli in the treated pigs than the controls. Conclusion: Although avilamycin selects for resistance in the native enterococci population of the pig, no resistant isolates were detected beyond 1 week post-treatment. This suggests that resistant isolates were unable to persist once selective pressure was removed and were out-competed by the sensitive microflora. Significance and Impact of the Study: Our data suggest the risk of resistant isolates becoming carcass contaminants and infecting humans could be minimized by introducing a withdrawal period after using avilamycin and prior to slaughter.
ARS Scientists Continue To Track Antimicrobial Resistant Organisms
The issues associated with Antimicrobial Resistance (AMR) continue to grow in complexity. The antimicrobials that we have used in humans, food producing and companion animals have continued to be challenged by bacteria that are developing resistance to these antimicrobial drugs. The scientists at the Agricultural Research Service (ARS) in Athens, Ga., are tracking these antimicrobial resistance patterns and looking for techniques that will aid in reducing the development of resistance.