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The control and management of Q fever outbreaks in ruminants are currently based on vaccination. Although buffalo (Bubalus bubalis) are intensively farmed in several countries and represent a reservoir for Coxiellosis, no evidence has been described regarding the efficacy of vaccination in this species. This work aimed to evaluate the humoral response, using appropriate phase-specific ELISAs, and the effects on abortion rate in buffalo by a field study. A total of 15 seropositive and 20 seronegative animals were vaccinated twice, three weeks apart, with a commercial phase I vaccine, and phase-specific antibodies were determined in the course of vaccination. Although anti-phase II antibody reactivity predominated after vaccination compared to phase I, both anti-phase I- and -phase II-antibody-reactivity significantly increased after the first (p = 0.001) and again after the second vaccination (p = 0.05). Seroconversion did not significantly depend on age or natural infection status. Once the vaccination cycle was completed, the herd study observed a reduced rate of abortion and placenta retention. Our data demonstrated that the vaccine principally induced a similar antibody response as in goats and sheep. These preliminary data appeared to support vaccination in buffalo, even in seropositive animals, although further studies are needed to better define the dynamics concerning seroconversion in this species., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A live, infectious vaccine candidate for epizootic bovine abortion, designated EBAA Vaccine, USDA-APHIS Product code #1544.00, has been reported to be both safe and effective. Previous studies established that a single dose of EBAA vaccine administered to cows at potencies of either 2000 or 500 live P. abortibovis-infected murine spleen cells (P.a.-LIC) induced protective immunity for a minimum of 5 months. The current study employed 19 pregnant cows that were challenged with P. abortibovis in their 2nd trimester of gestation; 9 were vaccinated 17.2-months earlier as 1-year-olds with 2000 P.a.-LIC and 10 served as negative controls. Eighty-nine percent of the vaccinates gave birth to healthy calves as compared to 10% of challenge controls. Vaccine efficacy was significant when analyzed by prevented fractions (87.7%; 95% CI=0.4945-0.9781). Serologic data supports previous findings that pregnant cows with detectable P. abortibovis antibodies are immune to P. abortibovis challenge as demonstrated by the birth of healthy calves., Competing Interests: Declaration of Competing Interest The author declared no conflicts of interest. The vaccine will not be produced for commercial distribution by either University of California or University of Nevada nor are there monetary incentives to authors or their institutions in association with potential vaccine sales., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Border disease virus (BDV) is a member of the pestivirus genus that primarily affects sheep, causing reproductive losses through abortion, still births and the birth of weak lambs. The key characteristic of this disease is the birth of persistently infected (PI) lambs which, after surviving transplacental infection, are born antibody negative, yet virus positive, and thus shed the virus for their entire life and are the primary source of spread within a flock. The cornerstones of BDV control are detection and elimination of PI animals, biosecurity measures to prevent re-infection, and surveillance programs. Recommendations for the control of BDV in sheep are centred around the approach to bovine viral diarrhoea virus (BVDV), the prominent cattle pestivirus species, due to a lack of specific research into BDV control and elimination. In this study, two aspects of a BDV control program were investigated: the effectiveness of the BVDV vaccine, Pestigard®, and the rate of seroconversion in a flock deliberately exposed to known PI lambs. The vaccine appeared to be safe, and the optimal dose was the full cattle dose (2 mL). While vaccination induced high virus neutralising titres to BVDV when administered as either a quarter, half or full dose registered for cattle, the BDV titres achieved were low and unlikely to prevent transplacental infection. In a second study, after exposure of between 2 and 15 days exposure to two PI lambs in confined conditions, only 3 of 66 previously naïve sheep demonstrated seroconversion. This demonstrated a very low rate of transmission and suggested that deliberate exposure to PI lambs at low-risk times for less than 15 days was not likely to be an effective means of achieving seroconversion throughout a flock and, therefore, not provide protection against BDV challenge during gestation., (© 2023 The Authors. Australian Veterinary Journal published by John Wiley & Sons Australia, Ltd on behalf of Australian Veterinary Association.)