- Animal Products: dairy
- Animal Production: herbal medicines, preventive practices, therapeutics
- Education and Training: demonstration, extension, on-farm/ranch research, workshop
- Production Systems: holistic management, organic agriculture
The mortality and antimicrobial use associated with neonatal calf diarrhea (NCD) is a critically important problem to the dairy industry. At the outset of this project, we aimed to 1) identify strategies to improve prevention practices for NCD, and 2) identify alternatives to antimicrobials for the treatment of NCD. At the end of the stated three-year period for the SARE proposal, we have met or exceeded the stated objectives for all three specific aims. In the first year of the project, we collected over 700 survey responses from conventional and organic dairy and calf producers in the Midwest. The results from this study have been critical to understand antimicrobial and non-antimicrobial treatment practices for both conventional and organic producers. The large sample size and representative nature have enabled precise estimates on prevention practices, antimicrobial use, and attitudes on non-antimicrobial alternative therapies for calf diarrhea. For instance, we identified specific barriers to the implementation of prevention practices known to be effective, but with poor rates of adoption (Pempek et al., 2017). Additionally, we found that producer attitudes on the public health impact of antimicrobial use were associated with antimicrobial treatment thresholds, suggesting that producer education is a viable intervention to reduce the quantity of antimicrobials used on farms (Habing et al., 2016). The data generated from this study were used to apply for additional grant funds, and our group was awarded a 1.2 million dollar USDA grant to use a similar approach towards adult dairy cattle.
To address the second aim of the project, we completed a large field trial on the impact of garlic extract and lactoferrin as treatments for calf diarrhea on organic farms. Importantly, the results demonstrate significant reductions in mortality when calves are treated with lactoferrin. These results were published within the Journal of Dairy Science (Habing et al., 2017). These results are highly relevant for organic producers, as the project has provided organic producers with a practical and efficacious tool for the treatment of diarrheic calves without the use of conventional antimicrobials. With additional funds from the project, we’ve conducted a multi-site randomized clinical trial on dairy farms in Ohio to confirm the initial findings, and further investigate the mechanism of lactoferrins efficacy. The results of this extension are pending.
The results from both aims were used to deliver an extensive extension program, including 30 1-day workshops/webinars that reached an estimated of 380 participants, including several veterinary practices from the north-central region. Furthermore, the research projects served to educate four different graduate or veterinary students.
Specific Aim 1
Our first objective was to use a cross-sectional survey to identify strategies to improve implementation of prevention practices, improve judicious antimicrobial use, and assess the use of non-antimicrobial alternative therapies by calf producers. The survey was designed with three sections that focused on each of the three components of the Aim. We selected a representative study population by obtaining lists of grade A dairy producers from the Departments of Agriculture in Ohio and Michigan, the list of certified organic dairy or calf producers from the USDA National Organic Program website, and a list of calf raisers belonging to the Dairy Calf and Heifer Association (DCHA). From a total of 3,967 grade A Dairy producers in Ohio or Michigan, 1,200 were randomly selected using a random number generator. Because of the low number of organic producers (321) and calf raisers (136), all certified organic calf or milk producers were selected for participation. In total, 1,657 producers were selected and mailed a survey. The survey response rate was exceptional. The original goal of 300 producers was surpassed by a wide margin, and a total of 632 (45%) of dairy producers returned the survey, including 173 organic and 459 non-organic dairy producers. Additionally, we received survey results from 37 (33%) of heifer raisers that were mailed the survey. Organic and conventional producers were provided with scenario-based descriptions of calf diarrhea that described either mild, moderate, or severe cases. Producers were provided with options for the treatment of diarrhea, which resulted in a clear picture when different antimicrobial alternatives are implemented by both organic and conventional producers. The survey also identified critical influencers of the lack of adoption of key calf management practices, which will be critical towards improving educational programs.The data from this survey has resulted in multiple scientific publications and meetings (see below). We expect the results to be critical to improve awareness among calf professionals and veterinarians on the critical needs of organic calf raisers, and to design additional research projects to address critical research gaps within organic calf production systems.
Specific Aim 2
Alternatives to antimicrobials are frequently used to treat calf diarrhea on organic operations; yet there is little data to support their effectiveness. In the second year of the project (2015), we conducted a blinded, randomized field trial lactoferrin and garlic extract for the treatment of calf diarrhea. Large field trials of diarrhea therapeutics are uncommon due to the requirement for a large number of clinical cases of diarrhea. We originally aimed to enroll 600 diarrheic calves, and randomize the calves to receive one of 3 treatments: garlic extract, lactoferrin, or a placebo. In the summer of 2015, we collaborated with a large organic dairy farm and enrolled 633 calves with diarrhea. Students working on the project clinically assessed calves enrolled in the project each day for 10 consecutive days, and additional treatments, deaths, and culls were recorded through the pre-weaning period. Importantly, calves enrolled in the lactoferrin treatment group had a significantly lower mortality rate. Lactoferrin significantly (p < 0.05) reduced the risk of death and culling in the preweaning period. In total, 7.5% (15/198) of calves in the control group died compared to only 3% (8/201) of calves treated with lactoferrin. Calves that received garlic extract had reduced mortality, but it was not significantly different from the control group.
Specific Aim 3
Our third specific aim, conducted over the past year (2016), was to develop and assess a comprehensive, research-based extension programming for dairy producers on best management practices, judicious antimicrobial use, and treatment protocols for calf diarrhea.
The original study aims and performance targets were as follows:
Specific Aim 1: To use a cross-sectional survey to identify strategies to improve implementation of prevention practices, improve judicious antimicrobial use, and assess the use of non-antimicrobial alternative therapies by calf producers.
Objectives/Performance Targets: We aimed to gather survey data from a total of 300 dairy producers or calf raisers. We set out multiple deliverables when we submitted the original proposal, including two peer-reviewed manuscripts addressing 1) producer-reported limitations associated with non-use of prevention practices and 2) producer knowledge, attitudes, and opinions of judicious antimicrobial use. We additionally aimed to present the results at multiple meetings of veterinarians and calf producers, including the American association of Bovine Practitioners and the American Dairy Science Association (ADSA).
Specific Aim 2: To develop evidence-based treatment protocols for calf diarrhea that incorporate non-antimicrobial alternative therapies.
Objectives/Performance Targets: We proposed and randomized clinical trial, and enrollment of a total of 600 calves, assigned to receive either lactoferrin, garlic extract, or control (water). We also proposed a scientific journal publication and multiple scholarly and producer-oriented presentations.
Specific aim 3: We proposed to develop and assess a comprehensive, research-based extension programming for dairy producers on best management practices, judicious antimicrobial use, and treatment protocols for calf diarrhea
Objectives/Performance Targets: We initially proposed four modules targeted to a subset of 20 Ohio dairy producers that covered topics on three main areas: 1) best calving and newborn management practices; 2) judicious antimicrobial use; and 3) evidence-based treatment protocols including the use of alternative therapies.