RT Journal Article
T1 Early Neospora caninum infection dynamics in cattle after inoculation at mid‑gestation with high (Nc‑Spain7)‑ or low (Nc‑Spain1H)‑virulence isolates
A1 Jiménez‑Pelayo, Laura
A1 García Sánchez, Marta Eulalia
A1 Vázquez Arbáizar, María Patricia
A1 Regidor‑Cerrillo, Javier
A1 Horcajo Iglesias, María Del Pilar
A1 Collantes Fernández, Esther
A1 Blanco Murcia, Francisco Javier
A1 Gutiérrez Expósito, Daniel
A1 Román Trufero, Alicia
A1 Osoro, Koldo
A1 Benavides, Julio
A1 Ortega Mora, Luis Miguel
AB Early Neospora caninum infection dynamics were investigated in pregnant heifers intravenously inoculated with PBS (G-Control) or 107 tachyzoites of high (G-NcSpain7)- or low (G-NcSpain1H)-virulence isolates at 110 days of gestation. Serial culling at 10 and 20 days post-infection (dpi) was performed. Fever was detected at 1 dpi in both infected groups (P < 0.0001), and a second peak was detected at 3 dpi only in G-NcSpain7 (P < 0.0001). At 10 dpi, Nc-Spain7 was detected in placental samples from one animal related to focal necrosis, and Nc-Spain7 transmission was observed, although no foetal lesions were associated with this finding. The presence of Nc-Spain1H in the placenta or foetuses, as well as lesions, were not detected at 10 dpi. At 20 dpi, G-NcSpain7 animals showed almost 100% positive placental tissues and severe focal necrosis as well as 100% transmission. Remarkably, foetal mortality was detected in two G-NcSpain7 heifers. Only one animal from G-NcSpain1H presented positive placental samples. No foetal mortality was detected, and lesions and parasite transmission to the foetus were not observed in this group. Finally, 100% of G-NcSpain7 heifers at 20 dpi presented specific antibodies, while only 60% of G-NcSpain1H animals presented specific antibodies at 20 dpi. In addition, earlier seroconversion in G-Nc-Spain7 was observed. In conclusion, tachyzoites from Nc-Spain7 reached the placenta earlier and multiplied, leading to lesion development, transmission to the foetus and foetal mortality, whereas Nc-Spain1H showed delayed infection of the placenta and no lesional development or transmission during early infection.
PB Springer
SN 0928-4249
SN 1297-9716
YR 2019
FD 2019-09-24
LK https://hdl.handle.net/20.500.14352/116342
UL https://hdl.handle.net/20.500.14352/116342
LA eng
NO Jiménez-Pelayo, L., García-Sánchez, M., Vázquez, P. et al. Early Neospora caninum infection dynamics in cattle after inoculation at mid-gestation with high (Nc-Spain7)- or low (Nc-Spain1H)-virulence isolates. Vet Res 50, 72 (2019). https://doi.org/10.1186/s13567-019-0691-6
NO Contributions:JRC, PH, ECF, JB, KO and LMOM conceived the study and participated in its design; LMO coordinated the study with the help of KO and obtained its funding. LJP and JB wrote the manuscript, with results interpretation and discussion inputs from PH, JRC, ECF, KO and LMOM; JBM and ART performed animal reproductive and health management prior to infection. PH prepared the inoculum. LJP, MGS, PV and ART monitored the animals during the experimental period; LJP and MGS processed the samples during the experiment and after culling but histological processing and examination that were carried out by DGE and JB. LJP, MGS, PV, JB, DGE, ART and KO participated in the collection of samples during necropsy. LJP, MGS, JB and DGE carried out statistical analysis and interpreted the results. All authors read and approved the final manuscript.
NO Ministerio de Economía y Competitividad (España)
NO Comunidad de Madrid
NO Universidad Complutense de Madrid
NO Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)
DS Docta Complutense
RD 17 abr 2025