Pet pigs are susceptible to worms, even when kept indoors. Worms of several types may infest a pig's lungs, stomach and small intestine, and can even invade his brain. Certain symptoms may point to worm infestation, but to find out for sure whether a pig has worms, collect a fecal sample and take it to a trusted veterinarian.
Pigs carrying a heavy parasite burden often have diarrhea. Though diarrhea may be a sign of a variety of health problems, including enteritis and dysentery, a variety of internal parasites can cause this loose-bowel symptom, too. Whipworms in the cecum and colon can cause bloody diarrhea, particularly in young pigs. Stomach worms may affect grazing pigs of all ages. Large roundworms, passed through feces, can affect weanling pigs and adults.
Failure to Thrive
Chronic failure to thrive and the inability to gain weight are symptoms of parasitic infestation. A mature pig may lose weight or fail to gain, while a young pig's growth may be stunted. Nodular worms or stomach worms in the large intestine and stomach may be responsible for these symptoms. Digestive illness and gastritis may occur as a result of an infestation. According to the Merck Veterinary Manual, symptoms of gastritis in pet pigs include anorexia and a bloated stomach as well as limited defecation.
Anemia and Illness
Pigs hosting parasites may be sluggish and anemic, and they may be prone to frequent illnesses due to suppressed immune systems. Large roundworms that migrate from the large intestine to the stomach may be responsible for causing favorable conditions for bacterial and viral pneumonia, according to the Department of Primary Industries. If roundworms are allowed to develop within the pig's stomach, they will eventually migrate to the bloodstream and lungs, where they are capable of causing serious damage.
Treatment and Prevention
To prevent internal parasites and the health issues they present, regularly dispose of all fecal matter in the pig's habitat, and start deworming regimens for all pet pigs over 20 pounds. Healthy adult pigs should receive Ivomec or another vet-approved dewormer twice a year, according to the website of the Aukland, New Zealand, Society for the Prevention of Cruelty to Animals. Ivomec can be given orally or injected.