Transmissible Gastroenteritis in Pigs: TGE Symptoms and Care

Transmissible gastroenteritis, usually called TGE, is a contagious intestinal disease of pigs caused by transmissible gastroenteritis virus (TGEV), a swine coronavirus. It spreads fast through infected pigs, manure, contaminated equipment, transport vehicles, clothing, and other fomites. The virus attacks the lining of the small intestine, causing villous atrophy, poor absorption, watery diarrhea, dehydration, and metabolic acidosis.

TGE can affect pigs of any age, but newborn and very young piglets are hit hardest. In piglets infected during the first week of life, mortality can be very high, especially in groups with little or no prior immunity. Older pigs usually have milder disease, but they still matter because they can shed virus and help drive an outbreak through a barn, backyard group, or small farm.

For pet parents with companion pigs or miniature pigs, the big concern is not only the diarrhea itself. It is how quickly a small piglet can become cold, weak, and dangerously dehydrated. Fast veterinary guidance matters because several pig diseases can look similar at first, and the care plan depends on age, hydration status, and how many pigs are affected.

TGE is caused by TGEV, an enteric coronavirus that infects and destroys absorptive cells in the jejunum and ileum. Once those intestinal cells are damaged, the gut cannot absorb fluids and nutrients normally. That leads to malabsorption, osmotic diarrhea, dehydration, and acid-base imbalance.

The virus is shed in large amounts in feces and spreads by the fecal-oral route, direct pig-to-pig contact, and contaminated boots, hands, feeders, buckets, trailers, and housing surfaces. Aerosol and close-contact spread can also contribute during outbreaks. Cold weather tends to favor survival of enteric coronaviruses, so severe epidemics are often more common in winter.

Not every exposed pig becomes equally sick. Age, immune status, and prior herd exposure matter a lot. Piglets with little maternal protection are at the greatest risk. In some herds, prior exposure to porcine respiratory coronavirus may reduce the severity of TGE, but it does not make diagnosis straightforward. That is one reason your vet may recommend laboratory confirmation instead of relying on signs alone.

Your vet usually starts with the history and outbreak pattern. TGE often causes rapidly spreading watery diarrhea across multiple pigs, with the worst losses in neonatal piglets. On exam, your vet will assess hydration, body temperature, nursing status, and whether the pattern fits a viral enteritis rather than a nutritional or bacterial problem.

A firm diagnosis usually needs laboratory testing because TGE can look very similar to other swine enteric coronaviruses and other causes of scours. Common tests include PCR on feces or herd-level samples, plus histopathology on intestinal tissue if piglets have died or humane necropsy samples are available. Some labs also use immunohistochemistry or related direct detection methods on fixed tissues.

Your vet may also test for PEDV, porcine deltacoronavirus, rotavirus, coccidia, E. coli, and clostridial disease at the same time. That matters because mixed infections can happen, and the herd response plan may change depending on what is found. Early sampling gives the best chance of getting a clear answer.

Prevention centers on biosecurity and immunity. Because TGEV spreads readily in feces and on contaminated surfaces, your best protection is to limit what comes onto the property and what moves between pig groups. That means careful control of visitors, boots, clothing, buckets, feeders, trailers, and manure-handling equipment. Avoid mixing pigs from different sources when possible, and work with your vet on a cleaning and disinfection routine that includes enough drying time for transport and housing surfaces.

If you keep breeding pigs, your vet may discuss vaccination of gestating sows to improve lactogenic immunity for piglets. Merck Veterinary Manual lists TGE-containing enteritis vaccines among recommendations for pigs at higher risk, with sow vaccination timed before first farrowing. Vaccination does not create complete protection in every setting, but it can be a useful part of a broader herd plan.

Good prevention also means acting fast when diarrhea appears. Isolate affected pigs, stop unnecessary movement on and off the property, and contact your vet early for testing. Quick diagnosis helps protect other pigs and reduces the chance that TGE, PEDV, or another contagious scour disease spreads through the whole group.