title: Replication of cytopathic and noncytopathic bovine viral diarrhea virus in zona-free and zona-intact in vitro-produced bovine embryos and the effect on embryo quality.
abstract: The aim of the present study was to determine whether or not cytopathic (CP) and noncytopathic (NCP) bovine viral diarrhea virus (BVDV) are able to replicate within in vitro-produced embryos and to investigate whether inoculation of embryos with BVDV affects their normal development. Zona pellucida (ZP)-free oocytes, zygotes, 8-cell-stage embryos, morulae, and hatched blastocysts (HB) were incubated for 1 h in 1 ml of Minimal Essential Medium containing 10(6.00) tissue culture infectious dose (TCID)50/ml NCP BVDV isolate 22,146 or 10(6.25) TCID50/ml CP BVDV strain Oregon C24V. At 0, 12, 24, 36, 48, 60, and 72 h postinoculation (hpi), groups of embryos were collected for virus titration. A small amount of newly produced virus was detected in 8-cell embryos at 60 hpi (10(1.8) TCID50/100 cells), but only for CP BVDV. For ZP-free morulae and HB, maximal intracellular virus titers were, respectively, 10(1.47) and 10(2.33) TCID50/100 cells at 48 hpi for the CP biotype and 10(0.64) and 10(0.84) TCID50/100 cells at 72 hpi for the NCP biotype. Only an infection with CP BVDV had a significant inhibitory effect on further development of ZP-free morulae. It can be concluded that ZP-free in vitro-produced embryos are permissive to an infection with BVDV, with increasing susceptibility of the embryos in accordance with their developmental stage. In contrast to observations in ZP-free in vitro-produced embryos, no virus replication or signs of embryonic degeneration were detected in ZP-intact in vitro-derived embryos.
authors.affiliation: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, University of Ghent, Merelbeke, Belgium. geert.vanroose@rug.ac.be
authors.forename: G
authors.initials: G
authors.lastname: Vanroose
authors.forename: H
authors.initials: H
authors.lastname: Nauwynck
authors.forename: A
authors.initials: A
authors.lastname: Van Soom
authors.forename: E
authors.initials: E
authors.lastname: Vanopdenbosch
authors.forename: A
authors.initials: A
authors.lastname: de Kruif
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000378:metabolism; D001755:Blastocyst / Q000166:cytology / Q000821:virology; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000517:prevention & control / Q000635:transmission / Q000821:virology; D002417:Cattle; D003588:Cytopathogenic Effect, Viral; D001908:Diarrhea Viruses, Bovine Viral / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology*; D004624:Embryo Transfer / Q000009:adverse effects / Q000662:veterinary; D004622:Embryo, Mammalian / Q000821:virology*; D005314:Embryonic and Fetal Development; D005307:Fertilization in Vitro; D066298:In Vitro Techniques; D014779:Virus Replication; D015044:Zona Pellucida / Q000502:physiology
chemical_list: D000956:Antigens, Viral