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What Are the Different Kinds of Roundworms?

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There are literally thousands of different types of parasitic nematode roundworms, most affecting a specific animal species. If you have a dog and cat, they might receive similar roundworm anthelmintics -- or dewormers -- but the medication gets rid of different worm species. Roundworms are also known as ascarids. They dwell in an animal's large or small intestine, but their larvae might spread elsewhere in the body.

Dog and Cat Roundworms

Canine roundworms include Toxocara canis and Toxascaris leonina, although the latter primarily affects felines. While Baylisascaris procyonis occasionally infests dogs, this roundworm primarily affects raccoons. Besides Toxascaris leonina, cats can also suffer from the parasite Toxocara cati. Dogs and cats pick up roundworms from ingesting eggs or eating infected animals. They can pick up the larvae as puppies and kittens from consuming their infected mothers' milk. Puppies can also pick up roundworms in utero, although this does not appear to be the case with kittens. Your veterinarian will advise you on a deworming schedule for your puppy, kitten and adult dog and cat.

Equine Roundworms

Parascaris equorum affects horses and donkeys. Ascarid eggs can live for years in the soil. After an equine ingest eggs, they hatch in the small intestine. Larvae also head to the liver and lungs. In the latter organs, they can cause significant damage. Severely affected horses develop a cough from larvae that migrate into the trachea. Adult roundworms live in the small intestine. A regular deworming program is crucial for equine health. Your veterinarian can advise you on the best deworming program for your part of the country.

Poultry Roundworms

Ascaridia galli affects turkeys and chickens. Birds with severe infestations experience weight loss and diarrhea, with possible fatal results. Female ascarids lay their eggs in the bird's intestine, which then pass out in fecal matter. Chickens or turkeys later eat the infected larvae. While piperazine, available over the counter, can eradicate adult roundworms, it doesn't work on immature worms. You'll have to repeat the deworming process on a regular basis to get rid of ascarids. Always follow piperazine package instructions carefully or ask your veterinarian for dosage information.

Swine Roundworms

Ascaris suum affects swine, whether the animals in question are raised for pork or live as pot-bellied house pets. The type of roundworm affecting people was previously believed to be Ascaris suum, but is now identified as Ascaris lumbricoides, according to Iowa State University College of Veterinary Medicine. Hundreds of those large roundworms can infest a single pig. Signs of roundworm infection in young swine include lack of weight gain and poor hair coat. In pigs, roundworm larvae can migrate to the lungs, causing pneumonia and death. They also migrate to the liver, resulting in scarring. It's important for farmers -- or pet pig owners -- to keep their animals on a strict deworming schedule.