All animals in this study were 4 months old at the time of inoculation. Sheep
(Suffolk cross, Rideau Arcott cross, Ile-de-France cross with Rideau Arcott) and goats (Alpine-Boer cross) were obtained from breeders in Manitoba. All animal manipulations were approved by the Animal Care Committee of the Canadian Libraries Science Centre for Human and Animal Health in compliance with the Canadian Council on Animal Care guidelines (Animal Use Documents #C-08-007, #C-09-004, #C-10-001, #C-11-011). The work with infected animals was performed under containment level 3 conditions (zoonotic BSL-3 Ag). Animals were acclimatized for two weeks prior to inoculation and inoculated subcutaneously MI-773 in vivo (SC) with 1 ml of RVFV (ZH501) into the right side of the neck, and if applicable re-inoculated SC or intravenously (IV) depending on the inoculation group. Two doses were compared: “low” dose of 105 PFU per animal and “high” dose of 107 PFU per animal. Rectal temperatures were taken for three days following arrival of the animal to the facility
and for minimum of five days prior to inoculation, Kinase Inhibitor Library cost and daily during the first week post inoculation. Except for the first group (sheep group A; see below), blood was collected daily for up to 6 or 7 days post inoculation (dpi). At this time point animals were either euthanized to determine virus presence in liver and spleen, or were kept up to 35 dpi for serum production, and bled weekly to follow antibody development (not reported in this manuscript). Overview of the inoculation groups is provided in Table 1. Where it was possible to group animals to compare two experimental
approaches, Student’s t-test was performed. A P value <0.05 was considered statistically significant. Sheep: Group S-A: eight animals (Suffolk cross) were inoculated with 105 PFU of RVFV prepared in Vero E6 cells. In this pilot trial, blood was collected at 3, 5 and 7 dpi. Group S-B: four animals (Rideau Arcott cross) were inoculated with 105 PFU of RVFV Vero E6 stock. Group S-C: four animals (Rideau Arcott cross) were inoculated with 105 PFU of RVFV C6/36-stock. Group S-D: four animals (Rideau Arcott Dipeptidyl peptidase cross) were inoculated with 107 PFU of Vero E6 stock. Group S-E: eight animals (Rideau Arcott cross) were inoculated with 107 PFU of C6/36-stock in two separate trials. Group S-F: four animals (Rideau Arcott cross) were inoculated with 107 PFU of C6/36 stock and re-inoculated at 1 dpi SC with the same dose. Group S-G: 4 animals (Rideau cross with Arcott or Ile de France) were inoculated with 107 PFU of the C6/36 derived virus stock, followed by IV inoculation with the same dose at 1 dpi. Most of the sheep were euthanized at 6–7 dpi, except for few animals kept for antibody production for 28 dpi. Some of the animals kept for production of antiserum were boosted at 14 dpi. Goats: All animals were Boer cross in groups of four. Group G-A was inoculated with 105 PFU of Vero E6 derived RVFV stock. Group B G-B was inoculated with 105 PFU of C6/36 derived RVFV stock.