Transmissible Gastroenteritis in Pigs: TGE Symptoms and Prevention

Transmissible gastroenteritis, often called TGE, is a highly contagious viral disease of pigs caused by transmissible gastroenteritis virus (TGEV), a swine coronavirus. It affects the small intestine, where it damages the cells that absorb nutrients and fluids. That damage leads to vomiting, profuse diarrhea, dehydration, and rapid weakness, especially in very young piglets.

TGE can affect pigs of all ages, but the disease is most dangerous in nursing piglets, particularly those under 2 weeks old. In this age group, fluid losses can become life-threatening very fast. Older pigs often survive, but they can still become ill and spread infection to others.

Outbreaks can move through a susceptible group quickly because the incubation period is short, often about 18 hours to 3 days. Some piglets nursing immune sows may stay healthier because antibodies in colostrum and milk help protect them. Even so, any sudden outbreak of vomiting and diarrhea in pigs deserves prompt veterinary attention.

TGE is caused by transmissible gastroenteritis virus (TGEV), a coronavirus that infects pigs. After a pig swallows the virus, it targets the lining of the small intestine. This damages the absorptive cells, so the intestine cannot handle fluids and nutrients normally. The result is sudden diarrhea, vomiting, and dehydration.

The virus spreads very easily between pigs through fecal-oral exposure and contaminated environments. In practical terms, that can include infected manure, boots, clothing, hands, equipment, trailers, and other shared items moving between groups. Like other swine diseases, indirect spread on people, vehicles, equipment, feed-contact surfaces, and farm traffic is an important biosecurity concern.

TGE occurs naturally in swine. In groups with little existing immunity, nearly all susceptible pigs may be exposed during an outbreak. Herd immunity can change how severe disease looks, and antibodies from the sow's colostrum and milk may help protect nursing piglets for a time. Because several pig diseases can cause very similar diarrhea outbreaks, your vet may recommend testing to confirm whether TGEV is the cause.

Your vet usually starts with the history and pattern of illness. A sudden outbreak of vomiting and diarrhea affecting many pigs at once, especially with severe disease in very young piglets, raises concern for TGE or another porcine coronaviral enteritis. Age matters too, because TGE is especially common as a cause of diarrhea in nursing and weaning pigs.

A diagnosis cannot be made reliably from signs alone. TGE can resemble porcine epidemic diarrhea (PED), porcine deltacoronavirus, rotavirus, coccidiosis, and bacterial causes of enteritis. Your vet may recommend fecal testing, PCR testing, and sometimes postmortem examination of recently affected piglets to identify the virus and rule out look-alike diseases.

Testing is also useful for herd management. Confirming the cause helps your vet guide isolation, sanitation, sow immunity planning, and monitoring of exposed pigs. If several pigs are affected, your vet may advise sampling more than one animal because timing and stage of illness can affect test results.

Prevention centers on biosecurity, sow immunity planning, and fast response to diarrhea outbreaks. Because TGE spreads quickly through contaminated manure, people, clothing, boots, equipment, and vehicles, it helps to limit unnecessary traffic around pigs. Clean coveralls and boots for each site, careful manure handling, and thorough cleaning and disinfection of equipment and transport vehicles all reduce the chance of bringing enteric disease onto the property.

If a pig develops sudden vomiting or diarrhea, separate affected animals as quickly as your vet recommends and avoid moving people or tools between sick and healthy groups. Keep feed and food waste away from pig areas, and do not allow pork products or outside food to contact pig spaces. Good sanitation in farrowing and nursery areas is especially important because newborn piglets are the most vulnerable.

Vaccination may be part of prevention on some farms or in higher-risk situations. Merck Veterinary Manual lists TGEV among enteric vaccines used in sows, with recommendations that include vaccination 5 and 2 weeks before first farrowing for higher-risk programs. USDA also lists a licensed porcine rotavirus-transmissible gastroenteritis modified live vaccine product. Your vet can help decide whether vaccination, herd immunity management, or both fit your pigs' situation.

Even with good prevention, no plan removes all risk. The most practical step is to have a response plan before a problem starts: know who to call, which pigs to isolate first, how to support hydration, and how to tighten traffic and sanitation immediately.