Mastitis is defined as an inflammation of the mammary gland and is prevalent in dairy herds around the world. Mastitis can be caused by a wide range of bacterial pathogens or from a physical force to the mammary gland and/or teat end. Antibiotics are frequently used to treat clinical mastitis, however often times antibiotics are either ineffective or not needed to treat the disease. Producers that use unnecessary antibiotics lose profit due to discarded milk and can contribute to antibiotic resistance. This project examined the effect on-farm culture had on decreasing the use of antibiotics on dairy farms, decreasing the costs associated with treatment of clinical mastitis, and increasing milk quality and profitability. Dairy producers that implemented the on-farm culture program found that overall Somatic Cell Count of their herd decreased an average of 90,000, 75% of participants experienced a decrease in antibiotic use, as well as, an average savings of $920 per farm due to judicious antibiotic usage. An added benefit to the on farm culture practices is every farm seen a decrease in clinical cases of mastitis. Participating producers experienced an average increase in profit of $5664 per farm based on lower levels of mastitis.
The majority of dairy producers are not implementing on-farm culture programs. A study recently published in the Journal of Dairy Science examined the effect on-farm culture programs had on antibiotic use, milk withholding time, and short-term clinical and bacteriological outcomes. This study found through the use of on-farm culturing, antibiotic use was reduced by half, milk withholding time decreased by 1 day, and no significant differences were found between days to clinical cure with cows treated immediately or waiting one day for culture results (Lago et al., 2011). Dairy producers may not be implementing on-farm culture programs for a variety of reasons including: lack of education and on-farm culture knowledge. Research shows that on-farm culture systems can be very beneficial to a producer.
This study examined what the barriers were for adopting an on-farm culture system, additionally determining how many farms across Pennsylvania would adopt this practice with the right education. Different dairy personnel such as veterinarians, extension educators, milk inspectors, and nutritionists can influence a farm’s decision making process. This study also examined if these different dairy influencers can help farms successfully adopt the on-farm culture program which reduced antibiotic usage and improved milk quality statewide. Dairy producers get paid milk premiums for good quality milk. Producers with mastitis in the herd have higher SCC’s and consequently suffer loss of these milk premiums. By identifying a bacterial pathogen, management strategies can be changed to help prevent/eliminate the spread of that particular pathogen from the herd. For example a producer cultures 3 cows with clinical mastitis and finds Staphylococcus aureus to be the causing pathogen. The producer can change or examine current milking routine to eliminate this pathogen from the herd. On-farm culturing helps producers pinpoint what management strategies they need to change to help reduce mastitis, as well as make more informed treatment decisions.
Educators set up 8 different herds across the state to allow producers and dairy influencers to see hands on demonstration of the success a farm can have by implementing an on-farm culture system. Surveys prior to the project start were done with each farm participating in the on-farm culture grant to examine current management practices and decisions regarding mastitis, as well as questions examining why on-farm culture has not been implemented. Follow-up surveys were also conducted at 6 months and during the last week of the project to examine changes in management practices and antibiotic usage.
The objectives and performance targets of this grant were updated at 6 months into the project due to several reasons. Andrea Tholen resigned from her position as extension educator with Penn State and as a result of this it made keeping up with our four western Pennsylvania farms difficult. There was not an educator based close to these farms to help with the culturing and make visits to keep them on track. One of the dairies on the project also took a loss in late December when all of their Hispanic milkers quit. This left the dairy with no one trained to culture, except the owner. As a result of this loss, this farm’s data is excluded from the project. The last challenge with the project was field days. Field days were to be held in early November 2013, but did not occur on time. They were held at a later date due to late corn harvest, many producers felt they were too busy to host a 2 hour field day. We also had one producer that wanted more time to culture and hoped to increase his management practices before he shared with other producers how culturing was going for him. We agreed to push the field days back to February or early March. Due to the loss of 1 producer’s participation in the grant, we held 3 field days instead of 4 (Fulton County, Mercer County, and Centre County). Participation at the field days was low and because of this the grant and on-farm culture project were shared at several conferences and meetings in the area. The grant project did not go exactly as planned, nor were all objectives met. However, adoption of new objectives half-way through the project were completed by project end and participants in the grant were happy with their results.
Eight different farms across Pennsylvania participated in the on-farm culture project, but only seven of the eight farm’s data was included in the results due to the reasons discussed previously. In April 2013, the eight farms participating in the grant were given a survey to examine current management practices, incidences of mastitis, antibiotic usage, current SCC, and barriers to on-farm culture. Additionally, each participating farm took part in a training program given by Andrea Dicke, Amber Yutzy, or Greg Strait, dairy extension educators trained in on-farm culture. After each farm was trained and confident in culturing, starting May 1, 2013 they recorded culture data including: cow ID, date, quarter, mastitis pathogen, treatment, days treated, days in milk (DIM), and lactation number. Farms made treatment decisions according to the reference guide for mastitis-causing bacteria released from Virginia Tech, or through consultations with their herd veterinarian (Petersson-Wolfe and Currin, 2010). The farms that participated in the grant implemented an on-farm culture program supported by the grant for a one year period (May 2013-April 2014).
During the month of March 2014 field days were held to share the results of the on-farm culture program to date. The goal of the field days were to get at least 25 small to medium sized farms across Pennsylvania to adopt on-farm culture. Adoption of this program by at least 25 farms would reduce antibiotic use associated with mastitis, reduce costs associated with treatment of mastitis, improve animal well-being, and increase milk quality/profitability statewide. In addition to the 3 field days, the on-farm culture process and grant project were shared at 5 separate meetings throughout the year including: Sensenig Nutrition Producer Meeting, Dairy Summit Demo Area, Extension Open House, Huntingdon Veterinary Producer Meeting, and Standing Stone FFA meeting.
Success of this project was measured monthly by dairy educators doing monthly check ups with cooperating farms. These monthly check ups made sure the project was moving in the right direction and that producers were keeping accurate records as well as understanding the culture process. Follow up evaluations were conducted at 6 months (November 2013) and during the last week of the project (April 2014) to determine if measurable improvements were made in milk quality through Somatic Cell Count(SCC), reduction in antibiotic use and costs associated with Mastitis treatment. Funding for the farms that were participating in the grant ended on April 30, 2014, due to the success of the project the 7 participating farms have continued using On Farm Culturing.
This section was combined with Impact and results
Eight farms accepted the on-farm culture project and starting culturing in May 2013. Of the 8 farms, 7 completed the project and have continued to culture. The total amount of milking cows across all farms that were monitored for mastitis was 519 cows. Of the 519 cows enrolled in the project, 109 culture samples were collected. More samples could have been collected, but according to treatment records handed in by participating farms we had 109 samples. The most common bacteria isolated from quarters included Staph spp. followed by Staphylococcus aureus, and then coliform type bacteria. When farms began to culture they adopted treatment protocols recommended by their veterinarians that fit their specific farm. Average SCC in April 2013 for the 7 farms was 231,000, during the middle 6 months 180,775, and at the end of the project 140,125.
A total of 30 dairy producers attended the “Best Milking Practices- “On Farm” Culturing” workshops statewide where the grant project was shared and participants were taught how to implement culturing on their farm. These producers represented 13 counties across Pennsylvania. Results of a post evaluation survey indicated the following:
o 89% of (n=21) intend to make treatment decisions based on mastitis causing pathogen discovered.
o 80% of (n=21) intend to use “on farm” culturing to manage mastitis on their farm. (obj.2)
o 73% of (n=21) increased their knowledge of the impact of clinical and subclinical mastitis on dairy farm profits.
o 73% of (n=21) increased their knowledge on the proper technique of setting up milk culture plates.
o 73% of (n=21) increased their knowledge on the ability to make better mastitis treatment decisions.
o 64% of (n=21) increased their knowledge on identification of bacteria on a milk culture plate.
- A six month follow up evaluation with workshop participants was implemented by phone with the following results:
o 100% of (n=20) implemented “on farm” milk culturing on their farm. (obj.2)
o 100% of (n=21) decreased the number of clinical cases of mastitis on their farm.
- Participants experienced an average increase in profit of $5664 per farm based on lower levels of mastitis.
o 75% of (n=20) decreased antibiotic use on their farm.
Participants experienced an average increase in profit of $920 per farm due to judicious use of antibiotics
Education & Outreach Activities and Participation Summary
Presentations were given introducing the idea of culturing, why it is important, and why it should be implemented. The following is a list of additional meetings presented at: Senseing Nutrition Producer Meeting (334), Producers Dairy Summit Demo (25), Extension Open House (37), Huntingdon Veterinary Producer Meeting (55), Standing Stone FFA (12) and Best Milking Practices: “On- Farm Culturing”(30). Details about the grant were shared with all participants at these meetings. In addition to the above meetings, 3 field days were held in March 2014: Mercer (15), Fulton (2), Centre (7). The field day held in Centre County had the most success with implementation; two producer’s implemented “on-farm” culturing within 3 days. Of the 493 people that attended the meetings stated above, 33 farms have implemented culturing on their farm. In addition to the outreach described above, Amber Yutzy and Greg Strait will present this project and its results at the National Association of County Agriculture Agents meeting to be held July 2014 in Mobile, Alabama. The success of the grant and other on-farm workshops earned the award of Northeast National Winner in Search for Excellence of Sustainable Agriculture and an invitation to present a poster at the national level. Approximately 1500 industry representatives and extension educators from across the USA will be in attendance. On-farm culture workshops will continue to be delivered across the state of Pennsylvania through the Penn State Extension Dairy Team’s educational programming; two locations (Mercer and Juniata County) are scheduled to be taught in 2015. It is the hope of the dairy team that more producers will implement this program due to the many benefits.
Financially, this project was able to help the 7 participating producers greatly. Average increase in profits was calculated using average herd size, milk production, decreased SCC, decreased antibiotic use and increased quality premium received. (Figures listed are average per farm)
- $1,495 average profit gained due to DECREASED cases of clinical mastitis.
- $2,500 average profit due to INCREASED production.
- $9,288 average profit due to INCREASED milk quality premium paid.
- $8,200 average profit due to DECREASED mastitis culls and deaths
Each farm that participated in the study had its own unique experience with the project. Some farms struggled with the culturing process due to different reasons: some farms had employees trained and then those employees later left the farm; other farms experienced the lack of clinical cases of mastitis due to excellent overall milk quality. We did have a few of the farms struggle with the process, while others thrived and had a good experience. The following are quotes submitted by the participating farms:
“The culturing program was very beneficial. Our SCC has dropped an average of 20,000 and we reduced our need to treat cows.”
“It helps to identify the causes and treat as needed, rather than treat every cow.”
“I knew what bacteria I was dealing with within 24 hours, I did not waste money on treating the wrong bacteria, I saved a lot of money by not treating the cows that didn’t have growth on the plates.”
“We were using CMT paddles on every cow that showed clinical signs and thought it was the best way to make management decisions on treatments. “
Areas needing additional study
Extension Educators Amber Yutzy and Greg Strait will travel to Alabama in July 2014 to present at the NACAA AM/PIC. Funds from the grant will be used to support this travel. They will also receive a National award for the work they have done with the grant.
Lago, A., S. M. Godden, R. Bey, P. L. Ruegg, and K. Leslie. 2011. The selective treatment of clinical mastitis based on on-farm culture results: I. Effects on antibiotic use, milk withholding time, and short-term clinical and bacteriological outcomes. J. Dairy Sci. 94(9):4441-4456.
C. S. Petersson-Wolfe and J. Currin, 2010. Virginia Tech Cooperative Extension.