RT Journal Article
T1 Isolation and characterization of a bovine isolate of Neospora caninum with low virulence
A1 Rojo Montejo, Silvia
A1 Collantes Fernández, Esther
A1 Regidor Cerrillo, Javier
A1 Álvarez García, Gema
A1 Marugán Hernández, Virginia
A1 Pedraza Díaz, Susana
A1 Blanco Murcia, Javier
A1 Prenafeta, Antonio
A1 Ortega Mora, Luis Miguel
K1 Neospora caninum
K1 Low virulence isolate
K1 Biological characterization
AB Neospora caninum tachyzoites were isolated from the brain of an asymptomatic naturally infected calf with precolostral-specific antibodies. The new isolate, named Nc-Spain 1H, was identified as a member of the N. caninum species based on its internal transcribed spacer 1 (ITS-1) sequence and was genetically characterized using microsatellite markers. Multilocus analysis showed that Nc-Spain 1H was genetically different from other N. caninum isolates. We compared the in vitro tachyzoite yield and viability rate of the Nc-Spain 1H and Nc-1 isolates in a plaque assay. The lower tachyzoite yields displayed by Nc-Spain 1H were complemented with a significantly lower viability rate. Moreover, in an in vitro tachyzoite–bradyzoite stage conversion assay, the percentage of Nc-Spain 1H bradyzoite conversion was similar to that of the cystogenic isolate Nc-Liv, with the exception that Nc-Spain 1H produced only intermediate bradyzoites. The pathogenicity of Nc-Spain 1H was examined in BALB/c mice, and the results demonstrated that Nc-Spain 1H failed to induce clinical signs or mortality and that no parasite DNA was detected in the brain during the chronic stage of infection. In a pregnant mouse model, Nc-1 infection resulted in high transplacental transmission, leading to a high neonatal mortality rate over time. In contrast, the offspring survival rate from Nc-Spain 1H-infected dams was almost 100%, and N. caninum DNA was detected in only one pup. These data show that Nc-Spain 1H appears to be a low virulence isolate and may be a suitable candidate for live vaccine development.
PB Elsevier
SN 0304-4017
YR 2009
FD 2009
LK https://hdl.handle.net/10347/39498
UL https://hdl.handle.net/10347/39498
LA eng
NO Veterinary Parasitology Volume 159, Issue 1, 22 January 2009, Pages 7-16
NO This work was supported by a project (PETRI 95-0777.OP) from the Spanish Government and Hipra Laboratories S.A. The Nc-Spain 1H isolate has been patented by the SALUVET group and HIPRA Laboratories S.A. (P200505316).
DS Minerva
RD 27 abr 2026