Mastitis Resistance to Enhance Dairy Food Safety

NON-TECHNICAL SUMMARY: Bovine mastitis is the most costly disease of dairy cattle. Single site studies are often limited in terms of expertise and cattle numbers. The scope and complexity of the problem is beyond the ability of any one institution. Collaborative efforts among researchers at various locations are needed to fully address the problem. The purpose of this project is to coordinate multistate and multidiciplinary research on bovine mastitis. Thus allowing sufficient resources to be focused on the problem.

<P>APPROACH: Bovine mastitis is the most costly disease affecting dairy cattle. While significant advances have been made in controlling some types of mastitis, the complex etiology of the disease dictates that new and more effective methods for control and treatment be developed. Single site studies are often limited in terms of expertise and cattle numbers. The magnitude and scope of attempting to solve mastitis related problems often extend far beyond the ability of any one institution. The ability to cooperate on a regional and national basis allows the integration of resources and knowledge on solutions for mastitis. Recognition of the need for a coordinated effort to study bovine mastitis resulted in the design and initiation of this multistate project. The project has provided a forum for new and established researchers to develop collaborative relationships, and to share resources and expertise. In recent years collaborative projects on a variety of mastitis projects have been conducted under this multistate project. Areas of research for objective 1 include evaluation of barrier dips for efficacy and isolation and evaluation of mastitis pathogens from clinical samples across the nation. Studies for objective 2 will involve determination of antimicrobial susceptibility of mastitis pathogens and comparison of these bacteria to environmental and human isolates to track changes in susceptibility. This will help determine the impact of mastitis therapy on increased resistance of bacteria in our environment. Under objective 3 our involvement in the heifer mastitis project will continue. In vitro evaluations of teat dips using the AOAC model will also continue. A new project studying the pathogenicity of the coagulase negative staphylococci is another area targeted for cooperative research under this project. Also under objective 3 will be studies on the effect of dairy lagoon effluent on environmental factors, including water quality and the presence of E. coli 0157:H7. The Mycoplasma mastitis control program in Louisiana will also continue under this objective.<P>

PROGRESS: 2007/01 TO 2007/12 <BR>
OUTPUTS: From participation in this multistate project two outputs have been generated. One proceeding paper at a national meeting was submitted and one peer review publication is set to be published in early 2008. Results from the study were also presented at the annual meeting of the multistate project on Mastitis Resistance to Enhance Dairy Food Safety and the Mastitis Research Workers annual meeting. <BR>PARTICIPANTS: Research Associate, Corinne Ray, and Extension personnel, Gary Hay, Chuck Griffin and Participants of the multi-state project. <BR>TARGET AUDIENCES: Target audiences for this project include other researchers in this field, dairy producers and dairy industry professionals.<BR><BR>IMPACT: 2007/01 TO 2007/12<BR>
This project is a newly written continuation of the longstanding multistate project on bovine mastitis. The purpose of the project is to coordinate multidisciplinary research efforts on mastitis that are being conducted at various laboratories throughout the United States. Research is being conducted in Louisiana on mycoplasma mastitis. Bovine mastitis caused by Mycoplasma species can be a highly contagious and devastating form of this disease that does not respond to therapy. Control is dependant on identification of problem herds and cows followed by sound management techniques to prevent further spread. Monthly bulk milk samples are collected under the guidance of the Louisiana Department of Agriculture and Forestry. Upon receipt, samples are plated to mycoplasma agar and bovine blood agar. Blood agar results are given to dairy producers to help them identify and control mastitis problems other than mycoplasma. Initial results prior to 2007 indicated an incidence of mycoplasma mastitis of approximately 2% in Louisiana dairy herds. Incidences of other major pathogens are Staph. aureus 20%, Strep. agalactiae 3-6%, Streptococcus spp. 30%, and Coliforms 15%. Results in 2007 from 545 bulk tanks cultured revealed 3 bulk tanks positive for Mycoplasma species and a drop in the overall incidence of mycoplasma mastitis to 0.05%. The implementation of an education, monitoring and control program combining monthly bulk tank culture with restrictions on sale of cattle from confirmed positive herds has reduced the incidence of this type of mastitis in Louisiana and heightened awareness and adoption of control measures. Other collaborative studies included in the project are studies on the importance of the coagulase negative staphylococci in bovine mastitis, and the impact of veterinary antibiotic therapy on antimicrobial resistance of bacteria.