The Swine Health Monitoring Project (SHMP) is a National program coordinated by Dr. Bob Morrison from the University of Minnesota, College of Veterinary Medicine. The goal of this initiative is to monitor the incidence and prevalence of relevant swine diseases in the US such as Porcine reproductive and respiratory syndrome (PRRS) or Porcine Epidemic Diarrhea (PED) for example. Participants are voluntarily sharing the health status of their farms in order to better understand, and in the future, control these illnesses. Each week participants receive a report including a one-page summary of a scientific fact of interest. From now on, the Science Page will be published on the blog here, every Friday.
In this meta-analysis conducted by the Center for Veterinary Health Surveillance (Madrid, Spain) in collaboration with Drs. Conrado, Perez, and Alvarez from the University of Minnesota, the efficacy of vaccination to control Salmonella infection in pigs was evaluated. The meta-analysis reviewed a total of 44 studies focusing on Salmonella typhimurium or Salmonella choleraesuis. Included protocols were using either inactivated (killed) or live-attenuated vaccines.
Results showed that both vaccine types had a similar efficacy and that the most successful control strategies among the ones reviewed were using killed vaccines to control Salmonella choleraesuis.
Abstract: Consumption or handling of improperly processed or cooked pork is considered one of the top sources for foodborne salmonellosis, a common cause of intestinal disease worldwide. Asymptomatic carrier pigs may contaminate pork at slaughtering; therefore, pre-harvest reduction of Salmonella load can contribute to reduce public health risk. Multiple studies have evaluated the impact of vaccination on controlling Salmonella in swine farms, but results are highly variable due to the heterogeneity in vaccines and vaccination protocols. Here, we report the results of an inclusive systematic review and a meta-analysis of the peer-reviewed scientific literature to provide updated knowledge on the potential effectiveness of Salmonella vaccination. A total of 126 articles describing the use of Salmonella vaccines in swine were identified, of which 44 fulfilled the inclusion criteria. Most of the studies (36/44) used live vaccines, and S. Typhimurium and S. Choleraesuis were the predominant serotypes evaluated. Vaccine efficacy was most often measured through bacteriological isolation, and pooled estimates of vaccine efficacy were obtained as the difference in the percentage of positive animals when available. Attenuated and inactivated vaccines had similar efficacy [Risk Difference = − 26.8% (− 33.8, − 19.71) and − 29.5% (− 44.4, − 14.5), respectively]. No serotype effect was observed on the efficacy recorded for attenuated vaccines; however, a higher efficacy of inactivated vaccines against S. Choleraesuis was observed, though in a reduced sample.
Results from the meta-analysis here demonstrate the impact that vaccination may have on the control of Salmonella in swine farms and could help in the design of programs to minimize the risk of transmission of certain serotypes through the food chain.
The Allen D. Leman swine conference is only six months away! Our team is preparing an exciting conference program for you this year and we will update you regularly on the speakers and topics that will be covered during this great event bringing science-driven solutions to the complex challenges facing the swine industry. We already shared with you that the recipient of this year’s Science in Practice award is Dr. Bob Thompson.
We are glad to announce that our first key note speaker for the conference will be Gary Louis, Executive Vice President of Seaboard Foods LLC where he is in charge of the live operations. We are delighted that he has accepted our invitation to share his tremendous experience and his vision of the swine production.
More information about the Allen D. Leman swine conference can be found here.
The UMN CVM students did a fantastic job at the 2017 American Association of Swine Veterinarians (AASV) meeting this past weekend. Four students presented their projects as an oral presentation. Zhen Yang, Alyssa Anderson, Hunter Baldry and Chris Deegan were all recognized by a jury for their hard work and commitment to the swine industry.
Taylor Homann, Donna Drebes, and Kevin Gustafson all got the opportunity to present their work as poster presentations.
Lastly, two out of the three awards given by Boehringer Ingelheim to advance the research on swine respiratory pathogens were given to Dr. Marie Culhane and Dr. Carlos Vilalta for their project on swine influenza and Porcine Reproductive and Respiratory Syndrome virus (PRRSV) respectively.
What disinfectant to use against Senecavirus A? Does it vary based on surface type or temperature? These are the questions that a group of researchers from the University of Minnesota – Veterinary Diagnostic Laboratory are answering in the latest issue of the Journal of Swine Health and Production (JSHAP).
The project tested: 3 disinfectants: Household bleach, a phenolic disinfectant, and a quaternary ammoniun-aldehyde 5 surfaces: aluminium, stainless steel, rubber, cement, and plastic 2 temperatures: 25°C (77F) and 4°C (39F)
Objectives: To evaluate the virucidal efficacy of three commercial disinfectants against Senecavirus A (SVA) on five different surfaces at ~25°C and 4°C.
Materials and methods: Household bleach, a phenolic disinfectant, and a quaternary ammonium-aldehyde disinfectant were tested at manufacturer’s recommended concentrations against a contemporary strain of SVA on aluminum, stainless steel, rubber, cement, and plastic surfaces at ~25°C and 4°C. Virus propagation and titration were performed on swine testicular cells. Viral titers were calculated before and after exposure to the disinfectant being tested.
Results: At ~25°C, household bleach at 1:20 dilution inactivated ≥ 99.99% of the virus within 10 to 15 minutes on aluminum, rubber, and plastic. On stainless steel and cured cement, it inactivated 99.97% and 99.98% of the virus, respectively. At 4°C, bleach inactivated ≥ 99.99% of the virus within 5 to15 minutes on all surfaces except rubber; on rubber, inactivation was 99.91% after 15 minutes. The phenolic disinfectant at the manufacturer’s recommended concentration inactivated only ≤ 82.41% of the virus at either temperature and on any surface, even after a 60-minute contact time. Results for the quaternary ammonium disinfectant were intermediate: 78.12% to 99.81% of the virus was inactivated within 60 minutes at both temperatures and on all surfaces. To detect differences between disinfectants, paired Wilcoxon tests were performed. At 10- and 15-minute time points, efficacies of the three disinfectants differed significantly.
Implications: Significant variation exists in the antiviral efficacies of different disinfectants. Hence, they should be tested against various pathogens before use in the field.