title: Influence of the gestational stage on the clinical course, lesional development and parasite distribution in experimental ovine neosporosis.
abstract: Neospora caninum is considered one of the main causes of abortion in cattle, yet recent studies have also emphasised its relevance as an abortifacient in small ruminants. In order to gain deeper insight into the pathogenesis of ovine neosporosis, pregnant ewes were intravenously inoculated with 10(6) tachyzoites of the Nc-Spain7 isolate at days 40, 90 or 120 of gestation. Infection during the first term resulted in the death of all foetuses between days 19 and 21 post-infection, showing mainly necrotic lesions in foetal liver and the highest parasite DNA detection and burden in both placenta and foetal viscera. After infection at day 90, foetal death was also detected in all ewes, although later (34-48 days post-infection). In this group, lesions were mainly inflammatory. Foetal livers showed the lowest frequency of lesions, as well as the lowest parasite detection and burden. All ewes infected at day 120 delivered viable lambs, although 3 out of 9 showed weakness and recumbency. Neospora DNA was detected in all lambs but one, and parasite burden was similar to that observed in day 90 group. Lesions in this group showed more conspicuous infiltration of inflammatory cells and higher frequency in foetal brain and muscle when compared to both previous groups. These results highlight the crucial role that the stage of gestation plays on the course of ovine neosporosis, similar to that reported in bovine neosporosis, and open the doors to consider sheep as a valid model for exogenous transplacental transmission for ruminant neosporosis.
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain. davidarranz@ucm.es.
authors.forename: David
authors.initials: D
authors.lastname: Arranz-Solís
authors.affiliation: Livestock Health and Production Institute (ULE-CSIC), 24346, León, Spain. j.benavides@eae.csic.es.
authors.forename: Julio
authors.initials: J
authors.lastname: Benavides
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain. jregidor@ucm.es.
authors.forename: Javier
authors.initials: J
authors.lastname: Regidor-Cerrillo
authors.affiliation: Livestock Health and Production Institute (ULE-CSIC), 24346, León, Spain. mfuef@unileon.es.
authors.forename: Miguel
authors.initials: M
authors.lastname: Fuertes
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain. iferrepe@ucm.es.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Ferre
authors.affiliation: Livestock Health and Production Institute (ULE-CSIC), 24346, León, Spain. mcfere@unileon.es.
authors.forename: Maria Del Carmen
authors.initials: Mdel C
authors.lastname: Ferreras
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain. esthercf@ucm.es.
authors.forename: Esther
authors.initials: E
authors.lastname: Collantes-Fernández
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty, University of Bern, CH-3012, Bern, Switzerland. andrew.hemphill@vetsuisse.unibe.ch.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hemphill
authors.affiliation: Livestock Health and Production Institute (ULE-CSIC), 24346, León, Spain. vperp@unileon.es.
authors.forename: Valentín
authors.initials: V
authors.lastname: Pérez
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain. luis.ortega@ucm.es.
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Ortega-Mora
mesh_terms: D000818:Animals; D003048:Coccidiosis / Q000469:parasitology / Q000635:transmission / Q000662:veterinary*; D016054:DNA, Protozoan / Q000235:genetics; D005260:Female; D005333:Fetus / Q000469:parasitology; D018445:Infectious Disease Transmission, Vertical / Q000662:veterinary*; D018688:Neospora / Q000235:genetics / Q000502:physiology*; D010920:Placenta / Q000469:parasitology; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000469:parasitology / Q000635:transmission*; D013997:Time Factors
chemical_list: D016054:DNA, Protozoan