Salmonella Vetovax™ SRP® Vaccine Trial at Kansas State University
- 180 cows enrolled from a 1,200 Holstein cow herd in Northern Kansas
- S. Agona isolated in trial cows
- Clinical salmonellosis apparent in neonatal calves, but not in cows
- Randomized in pairs: heifers and dry cows included
- 75 animals vaccinated with Salmonella Vetovax™ SRP®
- Vaccine booster 21 to 35 days after primary dose
- Booster 14 to 21 days before parturition
- Paired set of 75 controls given placebo
- All cows and heifers that were purchased after initiation of the study and not enrolled in the study were vaccinated by the herd manager with the Salmonella Vetovax™ SRP® vaccine
Overview of the results
- Both vaccinates and controls showed decreased Salmonella fecal shedding
- Decreased somatic cell count (SCC) in vaccinates vs. controls
- 179,000 vs 439,000 at 30-60 days in milk (DIM) (P<0.01)
- Mean parity adjusted average daily milk yield was greater in vaccinates
- Additional 1.14 kg/cow/day in the first 90 DIM (P<0.01)
- Vaccinated cattle had higher concentrations of circulating antibodies at both samplings: 7-14 and 28-35 DIM (P=0.01)
General conclusions
Vaccinating dairy cows with Salmonella Vetovax™ SRP® resulted in higher adjusted average daily milk yield (+1.14 kg), a decrease in SCC, and a significant increase in circulating antibodies. Since Salmonella bacteria are present on most dairy operations, this serologic response is positive. Vaccination with Salmonella Vetovax™ SRP® resulted in a significant increase in milk yield which may lead to improved profitability for dairy operators.
Salmonella Vetovax™ SRP® — a new vaccine using the innovative SRP® technology helping to prevent Salmonella Newport infections, reduce fecal shedding, and increase milk production in the context of subclinical Salmonella infections — is now available from Vetoquinol.
The Salmonella Vetovax™ SRP® vaccine represents an effective strategy to control Salmonella Newport outbreaks in dairy operations and a great way to keep milk production flowing.
Effect of Salmonella SRP vaccination
on milk production
+ 1.14 kg
Cows administered SRP vaccine showed a 1.14 kg increase in milk production per day.
Source: Kansas State University study
Effect of Salmonella SRP vaccination
on somatic cell count (SCC) (cells/mL)
59%