Swine & U column: Healthy pigs & discussion of virus & bacteria spread , By Diane Dewitte

A few summers ago, two UMN Extension colleagues and I hit the road with the University’s BEET (Biosecure Entry & Education Trailer) teaching 4-H members and their families the basics of biosecurity. Pig folks had already heard the term, and we had a great time working with all 4-H livestock exhibitors, showing them how easy it could be to prevent disease in their animals. And conversely, how easy it is to spread viruses & bacteria from people and equipment to animals.

Currently, exhibitors are picking out pigs for the summer’s shows, and it’s time to review some of the key points to keep the pigs healthy, in addition to youth and their families.



  • Quarantine new pigs for 14-30 days after you bring them home. Do not mix them with “home” pigs until the time has passed and you know that they are healthy.
  • Get recommended vaccinations for your pigs.
  • Monitor pigs for illness or health challenges.
  • Communicate with a veterinarian quickly about any illness.
  • Clean & disinfect pens and equipment regularly.
  • DO NOT share equipment with others.
  • Control pets, pests, and wildlife around your pigs.
  • Clean & disinfect trailer before & after each use.
  • Isolate animals after an exhibition.


Viruses occur in all species and can move very well between animals, which is one reason that quarantine of new animals is important. In the case of Zoonotic diseases, diseases which can infect both people AND pigs, it’s critical to exclude the virus.

  • Limit or eliminate visitors to your pigs. Viruses can be carried on clothing, shoes, and equipment.
  • Ask and know where your visitors have been, and do not allow anyone near your pigs who has pigs of their own, or who has recently traveled abroad.
  • Make sure everyone wears clean clothes and shoes when working with your pigs.
  • Do not feed uncooked garbage or swill to your pigs.
  • Make sure that your pigs are vaccinated against common viral diseases in pigs.

A study from the University of Minnesota’s College of Veterinary Medicine (Kim, Y., Yang, M., Goyal, S.M. et al. Evaluation of biosecurity measures to prevent indirect transmission of porcine epidemic diarrhea virus) showed that people who worked with pigs could reduce spread of the virus by using PPE (personal protective equipment) or practicing simple sanitation when moving between pig sites.

The study illustrated the value of “high biosecurity” (shower and complete change of clothes/footwear) and “medium biosecurity” (washing hands & face, plus changing footwear) in preventing the spread of PED virus among pigs. In both “high” and “medium” biosecurity groups, no pigs in the study became infected.

The “low biosecurity” group of pigs (caretakers did not change clothes or wash exposed skin when moving between pig groups) became infected within the first two days of the study. See the whole study here:  https://z.umn.edu/2017BiosecurityStudyUMN

Practices as simple as handwashing, wiping face, changing boots, stepping through a boot bath, and changing coveralls are proven to help prevent the spread of the virus to pigs and between pigs.

Humans can protect themselves by always washing their hands after working with animals. Do not eat or drink in the livestock area.


Our UMN swine researchers focus a lot of attention on the viruses that affect pigs, but we continue to face bacterial infections. Bacterial disease discussions below are from UMN’s Dr. Perle Zhitnitskiy’s Swine Diseases© textbook. I’m highlighting these three in particular because of their effect on young pigs, particularly those pigs the size of the new show pigs that exhibitors may be acquiring.

  • Streptococcus suis can cause disease in all ages of pigs, is common in every pig-raising country, and is found in the upper respiratory tract. It is considered an emerging zoonosis with the number of human cases rising in recent years, especially in Asian countries. Disease prevalence is usually only 5% of the pigs affected even if there may be 100% carriers. Transmission usually is nose-to-nose contact between pigs.
  • Escherichia coli (E. coli) is the cause of various symptoms in all stages of pigs, from diarrhea to urinary tract infection. The F18 strain affects 10–12-week-old pigs, and, contrary to other strains, is characterized by neurological symptoms rather than diarrhea. Many times, there is 50-90% mortality in nursery-age pigs. Pigs typically come into contact with the bacteria through a contaminated environment or due to fecal-oral transmission.
  • Glaesserella parasuis is a long-recognized bacteria which until 2020 was known as Haemophilus parasuis, but was renamed after the man who discovered it. G. parasuis is one of the main pathogens of importance in nursery pigs; it causes inflammation of lubricating surfaces in internal organs, and lameness. The bacteria are found in the upper respiratory system, but piglets first contract it when nursing the sow for colostrum. Nursing pigs also receive maternal antibodies against disease; Poor management practices that disrupt the balance between antibody protection and bacterial load cause the development of clinical signs.

➣ In each of these bacterial infections, the most severe outcome is unexplained death of the pig.

➣ Signs of the acute form of Glaesserella parasuis infection are first fever, followed by paddling, lameness, swollen joints and trouble breathing.

➣ Acute Streptococcus suis infection symptoms include fever & depressed behavior, followed by signs of meningitis, including paddling, head tilts and lack of coordination.

Treatment of these bacterial infections can be successful if pigs are injected with antibiotics; sick pigs will be too weakened to get up and consume medicated feed or water. Bacterial disease development can be prevented by good management and sanitation practices; most of these bacteria do not survive well in the environment.

Good ventilation and cleaning and disinfection of the barn and equipment is critical in controlling the bacteria population. Prevention of wide temperature variance helps prevent disease outbreaks.

In F18 E.coli a lineage of pigs that are resistant to the disease has been developed. Recently researchers at Iowa State University performed whole-genome sequencing of submitted G. parasuis isolates and are determining specific serotypes for production of autogenous vaccines and replacement animal selection.


Whether dealing with bacteria or viruses, sanitation of the barn, feed & water equipment, pens, and truck & trailer is an important step in breaking the cycle.

  • Always move pigs in a clean trailer and thoroughly clean show equipment, feeders, and waterers between shows. Mindful cleaning can prevent transmission of all common swine disease pathogens.
  • Carefully clean trailer – remove all manure, bedding and organic matter and dispose of it away from your home barns, pens, and pig lots.
  • Thoroughly wash inside and outside of livestock trailer. Wash outside of truck along with wheels and tires. Wash out the wheel wells of both truck and trailer.
  • Disinfect inside and outside of trailer. Clean inside truck cab. Disinfect floor mats and wipe down cab interior with disinfectant wipes labeled for surfaces.

General disinfectants for transport, equipment or barn surfaces include Tek-Trol Disinfectant, 1-Stroke Environ Germicidal, Synergize or Virkon-S. Use according to label directions.

Another suitable disinfectant is a Bleach solution of 1:10 parts bleach: water or ¾ Cup bleach per one gallon water.

Sources: Swine Diseases©, Perle Zhitnitskiy, DVM, MSpVM, https://open.lib.umn.edu/swinedisease/

Keep Your Show Pigs Safe! Biosecurity reminders to prevent disease in all of your pigs

Kim Y, Yang M, Goyal SM, Cheeran MC, Torremorell M. Evaluation of biosecurity measures to prevent indirect transmission of porcine epidemic diarrhea virus. BMC Vet Res. 2017 Apr 5;13(1):89. doi: 10.1186/s12917-017-1017-4. PMID: 28381304; PMCID: PMC5382501.

Diane DeWitte is a University of Minnesota Extension Educator based in Mankato. She can be reached at stouf002@umn.edu.