Publications by authors named "P J Gorden"
Objective: To describe immune responses following administration of experimental Salmonella Dublin siderophore receptor protein (SRP) vaccines in Holstein heifer calves with adequate passive antibody transfer.
Methods: Calves were randomly assigned to receive placebo, vaccination with S Dublin SRP in adjuvant A, or vaccination with S Dublin SRP in adjuvant B at 7 ± 3 days of age and 3 weeks later. Before each vaccination, 4 and 8 days after the second vaccination (postvaccination), and 61 to 91 days postvaccination, S Dublin antibody titers were measured.
The ability to reliably induce bovine digital dermatitis (DD) in naive calves provides unique opportunities to evaluate immune responses of the calves to infection after disease induction, during healing, and after subsequent re-infection. Dairy calves infected in a previous induction trial were held until lesions resolved and were then re-infected in parallel with naïve calves. Humoral and cell-mediated responses were assessed via serum antibody titer and lymphocyte proliferation analysis with responses of previously infected calves compared with responses of the newly infected calves and naïve calves.
View Article and Find Full Text PDFAnimals, including dairy cows develop hypocalcemia during infection. Prior independent research suggests supplementing oral Ca, but not i.v.
View Article and Find Full Text PDFArticle Synopsis
- - Highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.4b was detected in the U.S. in 2021, affecting poultry and wild animals while leading to significant losses in dairy production across multiple states by 2024.
- - A Texas dairy cow diagnosed with the virus showed symptoms like reduced feed intake, thick yellow milk, and decreased milk production, prompting investigations that identified more than 200 affected herds in 14 states.
- - Experimental infection in Holstein heifers and lactating cows confirmed the disease's mild clinical effects in heifers and more pronounced symptoms in cows, providing important groundwork for understanding transmission and potential interventions for future outbreaks.
Article Synopsis
- The highly pathogenic avian influenza virus A subtype H5N1, especially clade H5N1 2.3.4.4b, is emerging as a significant global health threat, now impacting cattle, which were previously thought to be less susceptible.
- Recent outbreaks on dairy farms in Texas, Kansas, and Michigan prompted a study investigating the presence of anti-nucleoprotein antibodies and viral RNA in milk and serum, demonstrating effective diagnostic methods.
- The study confirmed a strong correlation between serum and milk testing results and showed excellent diagnostic performance, highlighting the need for improved surveillance to manage the risk posed by H5N1-IAV in livestock.