Progress report for OS24-178
Project Information
The proposed solution is to evaluate the efficacy and cost-effectiveness of using AHV compounds as an alternative to antibiotics for treating mastitis in dairy cattle. This will be accomplished through a controlled field trial at a commercial USDA certified organic dairy farm, comparing udder health, milk quality, dairy cow performance, and economics between an AHV treatment group and non-treated control group.
Approximately 120 lactating Holstein dairy cows will be enrolled in the study, balanced between the AHV treatment and control groups. Cows will be selected based on elevated somatic cell counts (>350,000 cells/mL) indicating subclinical mastitis. The treatment group will receive the AHV mastitis regimen as designed by Agri-Dynamics, consisting of an initial dose of AHV Rapid followed by extended dosing of AHV Extend. The control group will receive standard herd management without AHV or antibiotics.
The efficacy of AHV therapy will be evaluated using milk somatic cell counts, milk bacterial counts and identification, and clinical mastitis incidence. Milk samples will be collected at the time of treatment assignment and then 25 days after the start of treatment. Somatic cell counts will be measured by DHIA testing. Bacterial counts and identification will be conducted at the lab using standard culture-based techniques. Clinical mastitis events (abnormal milk, swelling) will be recorded by farm staff throughout the study period.
Additional health and productivity outcomes will be analyzed to further assess AHV impacts, including milk production, rumination time, and survival/retention in the herd. Historical and ongoing milk yield, rumination, and electrical conductivity data will be obtained from the farm management system. Cow retention/survival will be compared between groups using survival analysis.
To evaluate cost-effectiveness, a partial budget analysis will be conducted from the farm perspective. Costs of AHV products, labor for treatment administration, and milk discarded in the CON group during treatment will be quantified based on farm records and valued at farm prices. The value of potential benefits such as reduced clinical mastitis, improved milk quality premiums, and higher milk production will be estimated based on study results and farm milk prices.
The expected key project outcomes are:
- Determination of AHV regimen efficacy based on somatic cell count reduction, bacterial inhibition, and clinical mastitis rate compared to non-treated cows
- Economic analysis indicating potential or lack of return on investment for AHV therapy under real-world conditions
- Documentation of impacts on milk production, cow health, and retention to provide a comprehensive assessment of AHV therapy
- Identification of any practical limitations or areas needing refinement for on-farm AHV use
- Scientifically-validated evidence to support or reject further research and adoption of AHV compounds as a non-antibiotic mastitis treatment
The results will objectively inform dairy producers, veterinarians, and the animal health industry whether integrating AHV therapy into organic dairy health protocols could be a viable strategy to combat mastitis. If proven effective and economical for on-farm use, AHV adoption would support sustainable agriculture by improving animal welfare and milk quality without antibiotics. However, if AHV treatment is found ineffective or cost-prohibitive, it highlights the critical need for research into additional alternatives for sustainable mastitis control. Either outcome will provide valuable evidence to guide practical solutions for reducing antibiotic use and mastitis impacts in the dairy industry.
This on-farm field trial will use a controlled experiment with enrolled cows randomly allocated to AHV treatment or control groups. The sample size of 120 cows is obtained using a sample size calculations in SAS with an effect difference of 10 percentage point reduction in mastitis incidence rate using 95% confidence to obtain a power of 80%.
A total of 218 lactating Holstein dairy cows are currently enrolled in the study, balanced between the AHV treatment and control groups. Cows are selected based on elevated somatic cell counts (>350,000 cells/mL) indicating subclinical mastitis. The treatment group will receive the AHV mastitis regimen as designed by Agri-Dynamics, consisting of an initial dose of AHV Rapid on day 0 followed by dosing of AHV Extend. The control group will receive standard USDA organic program-approved mastitis management without AHV or antibiotics which will include milking out the animals and monitoring the cow for clinical signs. Milk samples will be collected from both treatment and control groups on day 0 and day 25 after the enrollment. Udder health, milk quality, cow performance, and economic outcomes will be compared between groups using the following methods:
Somatic Cell Counts: Milk samples are aseptically collected from each quarter of enrolled cows at treatment start and 25 days after. Samples will be submitted to Texas DHIA for analysis of somatic cell count (SCC) using flow cytometry. The SCC results will be used to evaluate AHV efficacy in reducing subclinical mastitis as indicated by lowered SCC.
Bacterial Counts and Identification: Additional sterile quarter milk samples will be cultured by the TVMDL lab using standard protocols at treatment start and day 25. Bacterial species present and colony forming units/mL will be quantified to determine impacts of AHV on mastitis pathogens. PCR will identify major contagious (Staph aureus) and environmental (Strep species) pathogens.
Clinical Mastitis: Farm personnel will check cows 2X daily during the study, recording clinical mastitis events (abnormal milk, swelling). Clinical mastitis incidence will be compared between groups to assess effects of AHV treatment on clinical disease.
Milk Production: Milk yield data will be extracted from the on-farm management software for the week before and 4 weeks after treatment start. Daily milk production will be totaled and averaged by week for comparison between treatment groups.
Rumination and Conductivity: Historical and ongoing rumination time and milk electrical conductivity data will be obtained from the farm management system. Conductivity indicates mastitis and rumination is associated with cow health. Trends will be evaluated for AHV effects.
Retention/Survival Analysis: Cows will be tracked until dry off or culling to compare retention/survival between groups using Kaplan-Meier survival analysis. This evaluates potential milk production and cow health impacts.
Economic Analysis: A partial budget analysis will quantify costs of AHV products, labor, and discarded milk. Value of benefits such as reduced clinical mastitis and improved milk quality will be estimated based on results. Return on investment will be determined.
Lab bacteriology, PCR, somatic cell counting, and economic analysis will be conducted at the Texas A&M University facilities. On-farm data collection and cow enrollment will be performed by the farm staff with training provided. The controlled experiment with objective measurement of udder health, productivity, and economic outcomes will provide rigorous scientific evidence on the real-world efficacy and feasibility of AHV therapy. The methods align with the principles of sustainable agriculture by critically evaluating a potential non-antibiotic alternative to improve animal welfare and milk quality. Results will guide responsible practices to reduce reliance on antibiotics.
Project updates (3/13/2025): We have now enrolled the required number of cows in this study and following up to collect samples and analysis.
Cooperators
- - Producer
Research
PROJECT UPDATE (3/13/2025): The purpose of this project is to evaluate the efficacy and feasibility of using anti-biofilm hyper-activating (AHV) compounds as an alternative treatment for mastitis in dairy cattle. We enrolled and used 218 multiparous lactating Holstein cows with somatic cell counts (SCC) > 200,000 from a commercial organic dairy farm in central Texas. Cows were assigned randomly to the Treatment (TRT; n = 104) or Control (CON; n = 114) group, matched by parity and lactation stage. The TRT cows received plant-based antibiofilm bolus (AHV Rapid® or AHV Extend®; AHV, CA, USA), while CON cows did not. Composite milk samples were collected on day 0 (before treatment) and day 30 (after treatment) of the treatment for SCC and bacterial population dynamics analysis. Cow level milk electrical conductivity, yield, rumination time, and water intake were tracked from 7 days before to 30 days after treatment using Afimilk® and Smaxtec® devices.
PROJECT UPDATE (3/13/2025): We are currently evaluating the data and lab results as follow-up of the experiment to complete. We will report the results at a later progress report.
Educational & Outreach Activities
Participation Summary:
Objective of the Outreach Plan. The outreach plan is an integral component of this project. In addition to the research conducted at the Postmus dairy Farm, the treatment system will be demonstrated and disseminated at different locations.
Primary Outreach Goal: To educate and engage livestock producers, agricultural stakeholders, and the broader community about the benefits and implementation of nonantibiotic mastitis treatment system.
Secondary Outreach Goals: To promote sustainable agriculture practices and support underserved producers in the region.
Primary Audience: Dairy farmers (organic and conventional) in Texas.
Key Messages. AHV systems can help to manage mastitis in organic dairy farms. This system can be used in conventional dairy systems to minimize the use of antibiotics.
PROJECT UPDATE 3/13/2025
Outreach Tools and Channels.: The project team published an extension article in Texas A&M AgriLife extension portal. (Non-antibiotic-management-of-mastitis-in-dairy-cattle_March-2024.pdf)
We utilize the existing network of TAMU Organic extension program to disseminate our findings. Bob Whitney serves as Regents Fellow & Extension Organic Specialist for Texas A&M AgriLife Extension service (Agrilifeorganic.org). Articles and updates related to the project will be posted on this website on a regular basis.
The Texas Organic Agriculture Program routinely publishes blog posts that discuss organic agriculture. The blog has 1042 followers that receive the information upon publication. This outlet will be utilized to inform the organic stakeholders in the state about our research findings. Texas Organic News is a newsletter distributed by the Texas Organic Agriculture program which will be used to share the project related news. It is delivered to 394 email subscribers and is posted online at the Texas Organic Agriculture website where it is accessible for download and viewing by the public. We published this blog related to our research project . (Non-Antibiotic Management of Mastitis in Dairy Cattle – Texas A&M AgriLife Organic)
Project Outcomes
Project update 3/13/2025:
The project is currently undergoing. We will have further updates as we develop more results from the project and subsequently disseminate the findings.