Neospora Caninum
- caninum misdiagnosed as T. gondii till 1984 when it was first recognized in dogs in Norway as a new genus and species.
- Cause serious disease in cattle and dogs worldwide.
- Coccidian parasite with wide host range very similar in structure and lifecycle to gondii with two important differences
- Neosporosis is primarily a disease of cattle and dogs and related canids are definitive host of caninum.
- Toxoplsmosis is primarily disease of human, sheep, goats and cats. Cats and other felids are only definitive host of gondii.
Location and host
- Final host: Dog, other canids
- Intermediate host: Cattle
- Location: Brain, Heart, liver, placenta
Morphology
- Unsporulated oocyst in dogs measure 11.7 x 11.3 µm.
- Tachyzoites measure 6×2 µm and located in cytoplasm of cell.
- Tissue cysts are oval, 107 µm thick and have thick wall and found only in neural tissue.
- Cysts have no septa and enclose slender, 7×1.5 µm in diameter of bradyzoites.
Lifecycle
- Like in gondii , lifecycle is typified by three known infectious stage- tachyzoites, tissue cysts and oocyst.
- Tachyzoites and tissue cysts are found in intermediate host and occur intracellularly.
- Oocyst are excreted through feces of dogs as unsporulated oocyst. Sporulation occurs outside host at about 24 hours.
- Complete details in lifecycle are lacking
Mode of transmission
- Ingestion of contaminated food and water.
- Ingestion of raw uncooked meat of infected host.
- Transplacental infection
Clinical signs
- Both pups and older dogs gets infection, but more severe in young pups.
- Ascending paralysis with hind limbs more severely affected than fore legs.
- Difficulty in swallowing and paralysis of jaw.
- Ulcerative dermatitis, pneumonia, hepatitis and encephalitis may also occur.
- PM findings include: non-supportive encephalomyelitis, Acute necrotizing myocarditis and Phlebitis.
Diagnosis
- Detection of Ab in serum and in individual or bulk milk samples of cattle of indirect fluorescent antibody test and ELISA.
- Demonstration of parasite in biopsy specimens.
Treatment
- Unknown but drugs against toxoplasmosis can be tried.
Prevention and control
- As in gondii.