Project Number: LAB01903 CRIS Number: 0072330 MASTITIS RESISTANCE TO ENHANCE DAIRY FOOD SAFETY

Investigators: Nickerson, S. C., Owens, W. E.

Termination Date: 09/30/2002
Reporting period: 01/01/1999 TO 12/31/1999

Progress Report:
The objective of this study was to evaluate the use of a polyvalent Staphylococcus aureus vaccine in dairy heifers beginning at 6 months of age to determine if vaccination could reduce the prevalence of Staph. aureus mastitis during pregnancy and at the time of calving. Thirty-five heifers were vaccinated intramuscularly using a dose of 5 ml, and another 35 served as unvaccinated controls. At 2-month intervals after trial initiation, all heifers were bled and sera were stored for determination of antistaphylococcal antibody titers. Mammary secretion samples were also collected at these times for bacteriological culture and determination of somatic cell counts. Results demonstrated that thepercentage of new Staph. aureus infections occurring during pregnancy was lower in vaccinates compared with controls (14.3 vs. 25.9%). In addition, the percentage of quarters showing chronic Staph. aureus infection was lower in vaccinated heifers compared with control heifers (10.7 vs. 18.8%). Likewise, at freshening, the percentage of quarters infected with Staph. aureus was lower invaccinates compared with controls (8.9 vs. 16.1%). These data demonstrate a positive effect of vaccination in preventing new Staph. aureus infections when the program is initiated at an early age in heifers raised in a herd with high exposure to this mastitis-causing bacterial species.

Publications: (5)
Nickerson, S. C. Mastitis in heifers. Pages 135-147 in 2do Congreso Nacional de Control de Mastitis y Calidad de la Leche. Consejo Nacional de Mastitis A.C. Leon, Guanojuato, Mexico. 1999.

Nickerson, S. C., W. E. Owens, L. K. Fox, C. C. Schleifenger, T. R. Shryock, and T. E. Spike.  Comparison of tilmicosin and cephapirin as therapeutics for Staphylococcus aureus mastitis at dry-off. J. Dairy Sci. 82:696-703. 1999.

Nickerson, S. C., W. E. Owens, G. M. Tomita, and P. W. Widel. Vaccinating dairy heifers with a  Staphylococcus aureus bacterin reduces mastitis at calving. Large Animal Practice. 20:16-28. 1999.

Nickerson, S. C., W. E. Owens, S. M. DeRouen, R. L. Boddie, G. M. Tomita, J. M. Turpin, and S. P.  Galphin. 1999. Insecticidal tail tags reduce mastitis in beef cows. LSU Agricultural Center Beef Cattle Research Report. 30:19-21.

Owens, W. E., S. C. Nickerson, and C. H. Ray. Efficacy of parenterally or intramammarily administered tilmicosin or ceftiofur against Staphylococcus aureus mastitis during lactation. J. Dairy Sci. 82:645-647. 1999.

Impact:
Staphylococcus aureus mastitis causes significant losses to the dairy industry due to antibiotic treatment,  veterinary care, and culling costs. Prevention of this form of mastitis through vaccination has the potential of reducing the prevalence of this disease by 40 to 50% and increasing returns to the producer.