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Pet Owner Version

Neosporosis in Dogs


Dana G. Allen

, DVM, MSc, DACVIM, Ontario Veterinary College;

Bert E. Stromberg

, PhD, Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota;

J. P. Dubey

, MVSc, PhD, Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, USDA;

Paul Ettestad

, DVM, MS, Epidemiology and Response Division, New Mexico Department of Health;

Jodie Low Choy

, BVSc, BVMS, IVAS Cert, Menzies School of Health Research; University Avenue Veterinary Hospital, Northern Territory, Australia;

Joseph Taboada

, DVM, DACVIM, Office of Student and Academic Affairs, School of Veterinary Medicine, Louisiana State University;

Charles O. Thoen

, DVM, PhD, Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University;

John F. Timoney

, MVB, DSc, PhD, MRCVS, University of Kentucky;

Ian Tizard

, BVMS, PhD, DACVM, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University;

Geof W. Smith

, DVM, PhD, Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University;

Martin E. Hugh-Jones

, VetMB, MPH, PhD, MRCVS, School of Veterinary Medicine, Louisiana State University;

Henry R. Stämpfli

, DVM, DrMedVet, DACVIM, University of Guelph;

Kate E. Creevy

, DVM, MS, DACVIM-SAIM, College of Veterinary Medicine & Biomedical Sciences, Texas A & M University;

Gad Baneth

, DVM, PhD, DECVCP, Koret School of Veterinary Medicine, Hebrew University, Rehovot;

Katharine F. Lunn

, BVMS, MS, PhD, MRCVS, DACVIM, College of Veterinary Medicine, North Carolina State University;

Reinhard K. Straubinger

, DrMedVetHabil, PhD, Institute for Infectious Diseases and Zoonoses, Department of Veterinary Sciences, Faculty of Veterinary Medicine, LMU;

Márcio Garcia Ribeiro

, DVM, PhD, São Paulo State University - UNESP;

Thomas Wittek

, Univ.Prof. Dr., DECBHM, Clinic for Ruminants, Vetmeduni Vienna;

Yasuko Rikihisa

, PhD, Ohio State University;

Janet E. Foley

, DVM, PhD, Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis

Last full review/revision Jun 2018 | Content last modified Oct 2020
Topic Resources

Neosporosis is caused by the protozoan parasite Neospora caninum. Neosporosis has been recognized in dogs, cattle, horses, and other animals, but the dog is the definitive host. (A definitive host is an animal that a parasite requires in order to mature normally.) Infection is uncommon but can be acquired by ingesting contaminated food and water, or ingesting infected tissues. It may also be transferred from a mother to a fetus still in the womb (transplacentally). The disease is best known for causing loss of pregnancy in cows, especially on farms with dogs.

Neosporosis, dog

Neosporosis, dog

Dogs typically do not show signs of infections However, signs may be seen in some puppies and adult dogs. Most severe infections occur in young puppies, which typically develop partial paralysis of the legs, particularly the hind legs. The paralysis is often progressive and results in rigid contracture of the muscles. The outlook for these puppies is poor. In adult dogs, neurologic signs (such as inflammation of the brain and spinal cord), skin inflammation with sores, inflammation of the liver, pneumonia, and inflammation of the heart may occur. The outlook worsens in dogs with severe signs or those that are not treated promptly.

Your veterinarian will recommend proper antibiotic treatment. There is currently no vaccine.

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