Field evaluation of a new single-dose Mycoplasma hyopneumoniae bacterin effects on growth performance

Abstract

Objective: Evaluate the efficacy of a new single-dose bacterin against Mycoplasma hyopneumoniae under field conditions. Materials and methods: Three separate farms were selected based on their history of enzootic pneumonia. On each farm, vaccinated pigs (n = 20; 10 male and 10 female) were administered a single dose of the M hyopneumoniae bacterin at 21 days of age while unvaccinated pigs (n = 20; 10 male and 10 female) were administered a single dose of phosphate buffered saline at the same age. Results: Vaccination against M hyopneumoniae reduces the severity of lung lesions and clinical signs such as coughing, which leads to improved growth performance of the pig. Vaccinated pigs had a significantly higher (P = .02 for farm A, P = .02 for farm B, and P = .02 for farm C) average daily weight gain between 21 to 175 days old (0 to 154 days post vaccination) and elicited cell-mediated immunity, as measured by M hyopneumoniae-specific interferon-γ secreting cells, when compared with unvaccinated pigs located at all 3 farms. Implications: The data presented in this field study demonstrated that the M hyopneumoniae bacterin improved growth performance effectively in 3 farms suffering from enzootic pneumonia.