MASTITIS RESISTANCE TO ENHANCE DAIRY FOOD SAFETY

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0230224
• Project No.: LAB94151
• Multistate No.: NE-1048
• Project Start Date: Oct 1, 2012
• Project End Date: Sep 30, 2017

Project Director
Owens, WI.

Recipient Organization
LOUISIANA STATE UNIVERSITY
202 HIMES HALL
BATON ROUGE,LA 70803-0100

Performing Department
Hill Farm Research Station

Non Technical Summary
In the United States, cash receipts from marketing of milk during 2010 totaled $31.4 billion and it is estimated that U.S. consumers spend approximately 11% of their food dollars on dairy products. However, the dairy industry continues to experience significant monetary drain through the losses associated with common diseases. Bovine mastitis is the most costly infectious disease currently affecting dairy cattle. Recent estimates suggest that economic losses due to clinical and subclinical mastitis are in the range of $200 per cow per year. These losses are primarily due to lost milk production, increased veterinary costs, increased cow mortality, and discarded milk. While significant advances have been made in controlling some types of mastitis, the complex etiology of the disease and ongoing changes in dairy practices dictate that new and more effective methods for control and treatment be developed over time. Single site studies are often limited in terms of expertise and cattle numbers. A multi-state project provides advantages in terms of increased numbers of herds and cattle as well as multiple levels of expertise. The purpose of NE-1048 is to coordinate multidisciplinary research efforts on mastitis that are being conducted at various laboratories throughout the United States. The magnitude and scope of attempting to solve these problems 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 to address this problem. Recognition of the need for a coordinated effort to study resistance of the dairy cow to mastitis resulted in the design and initiation of multi-State Project NE-1048. The NE-1048 project has provided a forum for new and established researchers to develop collaborative relationships, and to share resources and expertise. The NE-1048 project is comprised of three objectives 1) characterization of host mechanisms associated with mastitis susceptibility and resistance, 2) characterization and manipulation of virulence factors of mastitis pathogens for enhancing host defenses, and 3) assessment and application of new technologies that advance mastitis control, milk quality, and dairy food safety.

Animal Health Component

50%

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
311	3410	1100	50%
711	3410	1100	50%

Knowledge Area
311 - Animal Diseases; 711 - Ensure Food Products Free of Harmful Chemicals, Including Residues from Agricultural and Other Sources;

Subject Of Investigation
3410 - Dairy cattle, live animal;

Field Of Science
1100 - Bacteriology;

Keywords

mastitis, antimicrobial susceptibility testing, antimicrobial

resistance, teat dips

Goals / Objectives
Objective 2: Characterization and manipulation of virulence factors of mastitis pathogens for enhancing host defenses. A major achievement for this objective is the continued examination of the role of coagulase-negative staphylococci on mastitis. More detailed examination of this diverse group of bacteria, including genotypic identification, has revealed that different species have surprisingly different effects on pathogenesis. Some species cause little or no decline in milk production. Additional progress is being made on using PCR-based techniques to identify pathogens in high SCC milk that had previously been declared as no growth using traditional culture techniques. This will be of great, widespread importance in mastitis treatment and research. Continued work exploring the development of bacterial resistance to commonly used antimicrobials is providing needed information on this critical treatment of mastitis. Antimicrobial resistance patterns of bovine and human isolates appear similar, and recent work suggests that mastitis therapeutics do not seem to induce or select for resistant bacteria. Additional achievements include further identification of pathogen virulence factors and their association with mastitis pathogenesis, and detailed in vitro studies on bacterial adherence to, and penetration into mammary epithelial cells. Objective 3: Assessment and application of new technologies that advance mastitis control, milk quality, and dairy food safety. Achievements include evaluation of S. aureus and E. coli mastitis vaccines; development and application of milk residue testing; development of control programs for S. aureus and Mycoplasma spp.; evaluation of extended therapy for S. aureus and S. uberis mastitis and assessment of methods for on-farm and laboratory diagnosis of mastitis and food-borne pathogens. Improvements in diagnostic technologies include development and application of PCR to detect Mycoplasma mastitis; to identify and speciate pathogenic Prototheca (algae) as a screening technique for bulk tank filters; and to validate 16S gene sequence analysis for mastitis pathogen detection. These molecular techniques are critically important tools in mastitis treatment. Other achievements include developing and assessing techniques for evaluating milk quality in sheep and goats; and evaluation of an in-line milk analysis system for somatic cell count and other quality assessment components; and studies of colostral quality assessment methods. Finally, several workers have reported on alternative methods of preventing (probiotic) and treating (botanical/novel intramammary infusions) mastitis.

Project Methods
Objective 2: Characterization and manipulation of virulence factors of mastitis pathogens for enhancing host defenses. (ii) Antimicrobial Resistance Continued monitoring of antimicrobial resistance of mastitis-causing pathogens is of utmost importance to determine if such resistance is emerging or progressing. Work in this area will be carried out at several stations (KY, LA, VT). LA and VT will continue to evaluate the impact of agricultural use of antibiotics on bacterial resistance to antibiotics. Comparison of resistance patterns between bovine and human associated isolates will be performed (LA). Additionally, VT will examine potential associations between carriage of antimicrobial resistance genes and response to antimicrobial therapy among different strain types of S. aureus and S. uberis. The effect of ensiling on antibiotic resistance of enterococcal isolates will be examined by VA. The minimum inhibitory concentrations of various cephalosporin compounds for several mastitis pathogens will be evaluated (WI) with the goal of improving treatment options. In addition, WI will characterize genotypic and phenotypic patterns of resistance for a large number of mastitis pathogens collected from a cross section of large Wisconsin dairy farms. Objective 3: Assessment and application of new technologies that advance mastitis control, milk quality and dairy food safety. Twenty-two stations have stated that they have been, or will be working on Objective 3-related projects, although many projects are relevant to more than one objective. Antimicrobials, including injectable and extra-label use antibiotics, will be evaluated at the Georgia station, along with a method to evaluate goat milk SCC. ID will evaluate teat dips, continue the collaboration with MN and CA studying dry cow treatments, and begin a mastitis vaccine evaluation trial. LA will assess the impact of dairy practices on antibiotic resistance in the human population.

Progress 10/01/12 to 09/30/17

Outputs
Target Audience:Dairy producers in Louisiana, mastitis research scientists, dairy producers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Mastitis Research Workers/NE 1048 Multistate Project annual meeting, Chicago, Il. November, 2016, Meeting provides for presentation of data and discussion of new research ideas. Allows multistate project members to meet with administrative personnel from the project and learn new regulations and procedures. How have the results been disseminated to communities of interest?Annual report of the NE 1048 Multistate project Articles in Louisiana Argiculture (2017) What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Milk samples from both cattle and goats were processed for mastitis pathogens by the Hill Farm mastitis laboratory. Mastitis pathogens were identified, and recommendations for mastitis control were made. Mastitis pathogens were collected and stocked for additional studies. A journal article on goat mastitis was published. Novel food based antimicrobial products continue to be evaluated with Dr. Zhijun Liu. Products are tested against mastitis pathogens for potential antibacterial activity. A Louisiana Agriculture article summarizing this study has been accepted and will appear in the Winter 2017 issue.

Publications

• Type: Other Status: Published Year Published: 2017 Citation: Liu Zhijun, William E Owens, Yixuan Dong and Jian Zhang. Antibacterial Botanical Formulations. Louisiana Agiculture 2017 Vol 60, No. 1. Pp.18-19 .

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:dairy producers in Louisiana, mastitis research scientists, dairy fieldmen, dairy goat producers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The Mastitis Research workers annual meeting and the NE 1048 Multistate project meeting was held in Memphis, TN, in conjunction with the NMC international meeting. I chaired the MRW meeting and served as secretary/treasurer. Reports and information from the project were shared in a two day meeting with scientists from around the world. How have the results been disseminated to communities of interest?Each year the members of the Multistate project provide reports at the yearly symposiumon the research done under the project. In addition, the Zoetis project, which evaluates antimicrobial susceptibilities to antibiotics used against mastitis, is made available to research scientists in the field via a report from Zoetis that summarizes the results from all participants. What do you plan to do during the next reporting period to accomplish the goals?The Zoetis project will continue. The studies on mastitis pathogens in goats will continue. A journal article on goat mastitis is planned for 2016. Owners of problem herds in Louisiana will continue to send samples and receive advice on mastitis management. The 2016 annual meeting of NE 1048 and the Mastitis Research Workers will be attended in Glendale, Arizona in February.

Impacts
What was accomplished under these goals? Milk samples from problem dairy herds in Louisiana and other states were processed for mastitis pathogens by the Hill Farm laboratory. Mastitis pathogens from these samples were evaluated for antimicrobial susceptibility. Isolates were also sent to Zoetis for additional testing and comparison to mastitis pathogens across the nation. Results were compiled and made available through the Zoetis program to mastitis laboratories across the nation. Milk samples from problem dairyherds in Louisiana were evaluated for mastitis pathogens, and producers were advised on mastitis control methods. Milk samples from goats in Louisiana and other southern states were also evaluated for mastitis pathogens, and owners were advised on mastitis control methods. Mastitis pathogens from goats were identified and evaluated for antimicrobial susceptibility patterns. The predominant mastitis pathogens from goats were staphylococci, and minimal antimicrobial resistance was detected. A survey of goat producers revealed an inconsistent pattern of adoption of mastitis control procedures, and recomendations for adoption of proper methods were made.

Publications

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: dairy producers in Louisiana, mastitis research scientists, dairy fieldmen Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The Mastitis Research workers annual meeting and the NE 1048 Multistate project meeting was held in Ghent, Belgium, in conjunction with the NMC international meeting. Reports and information from the project were shared in a two day meeting with scientists from around the world. How have the results been disseminated to communities of interest? Each year the members of the Multistate project provide reports at the yearly meeting on the research done under the project. In addition, the Zoetis project, which evaluates antimicrobial susceptibilities to antibiotics used against mastitis, is made available to research scientists in the field. What do you plan to do during the next reporting period to accomplish the goals? The Zoetis project will continue. The studies on mastitis pathogens in goats will continue. A journal article on goat mastitis is planned for 2015. Owners of problem herds in Louisiana will continue to send samples and receive advice on mastitis management. The 2015 annual meeting of NE 1048 and the Mastitis Research Workers will be attended in Memphis, TN, in February.

Impacts
What was accomplished under these goals? Milk samples from problem herds in Louisiana andother states were processed by the Hill Farm laboratory. Mastitis pathogens from these samples were evaluated for antimicrobial susceptibility. Isolates were also sent to Zoetis for additional testing and comparison to mastitis pathogens across the nation. Results were compiled and made available through the Zoetis program to mastitis laboratories across the nation. Milk samples from problem mastitis herds in Louisiana were evaluated for mastitis pathogens,and producers were advised on mastitis control methods. Milk samples from goats in Louisiana and other southern states were also evaluated for mastitis pathogens, and owners were advised on mastitis control methods. Mastitis pathogens from goats were identified and evaluated for antimicrobial susceptibility patterns.

Publications

Progress 10/01/12 to 09/30/13

Outputs
Target Audience: Dairy producers, research scientists and extension agents, dairy industry personnel Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? A Hill Farm representativetravels each year to the annual meeting of the Zoetis antimicrobial susceptibility project to discuss the results. The annual meeting of the Mastitis Research Workers and the multistate project is attended each year. I serve as the secretary/treasurer of the Mastitis Research Workers Group. Yearly meetings are held with the Louisiana dairy commodity group to discussproducer needs for mastitis management. How have the results been disseminated to communities of interest? Results are reported via the dairycommodity meeting of the LSU AgCenter.The annual meeting of this multistate project serves as a forum to report results from participating member institutions.A yearly report from the multistate project is made to NIFA each year from the group. The summary meeting of the Zoetis program will be attended, and results will be made available to members of the multistate project. What do you plan to do during the next reporting period to accomplish the goals? The mycoplasma mastitis program will continue. The annual meeting of this multistate project will be attended. Producers milk samples from dairy goat and cows will continue to be processed for identification ofmastitis pathogens, and results provided to producers to help them manage their mastitis problems. Participation in the Zoetis antimicrobial resistance program will continue.

Impacts
What was accomplished under these goals? The purpose of this project is to coordinate multidisciplinary research efforts on mastitis being conducted at various laboratories throughout the United States. Mastitis pathogens from dairies in Louisiana are being collected and submitted to the Zoetis antimicrobial susceptibility project.Results from this project are distributed nationally by Zoetis to participating laboratories. A summary of the Hill Farm's participation in this study is planned for 2013.Results indicate minimal resistance to commonly used antibiotics in mastitis pathogensdespite continual use of those antibiotics in cattle.Milk samples from dairy goatsare being evaluated at the Hill Farm and results on pathogen identification are reported to producers to help manage mastitis in dairy goat herds. Bulk samples from dairies in Louisiana continue to be monitored for identification of Mycoplasma species and other mastitis pathogens; results are used to help Louisiana dairy producers manage bovine mastitis in their herds.

Publications