Evaluation and Documentation of Homeopathic Nosodes in Organic and Conventional Dairy Production

Final Report for LNE97-086

Project Type: Research and Education
Funds awarded in 1997: $161,026.00
Projected End Date: 12/31/2001
Matching Federal Funds: $23,800.00
Matching Non-Federal Funds: $30,413.00
Region: Northeast
State: Vermont
Project Leader:
Lisa McCrory
Northeast Organic Farming Association of Vermont
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Project Information

Summary:

[Note to online version: The report for this project includes tables that could not be included here. The regional SARE office will mail a hard copy of the entire report at your request. Just contact Northeast SARE at (802)-656-0471 or nesare@uvm.edu.]

Organic and conventional dairy farmers have been using homeopathic remedies with limited technical support or evidence of efficacy. Research is lacking that documents the effectiveness of various homeopathic remedies for treatment of animal production health problems.

In this research project, the use of homeopathic remedies was evaluated for the treatment and prevention of mastitis in dairy cattle and E. coli calf scours in calves. To the best of our knowledge, this was the largest placebo controlled, double blind clinical field trial of nosode efficacy for the prevention of mastitis among dairy cattle.

This project resulted in the improved understanding of alternative health therapies for use in dairy production. Research results were disseminated, and educational programs were provided to farmers, extension educators, and researchers on the efficacy of homeopathy in the treatment and prevention of dairy cattle diseases, with a focus on mastitis.

Methods/approach: A placebo-controlled double-blind clinical trial evaluating the effectiveness of homeopathic nosodes for prevention of mastitis and calf scours was initiated in September 1997 with the enrollment of 11 dairy farms, including over 1000 lactating cows and 300 calves. The research was conducted by the Northeast Organic Farming Association of Vermont, and included the collaboration of the University of Vermont Quality Milk Research Laboratory.

Effect of treatment on mastitis rates was evaluated by bacteriological culture of duplicate quarter milk samples from all cows at various time-points across lactation. Differences between treatment groups in prevalence of all intra-mammary infections (IMI), prevalence of new IMI, rates of clinical mastitis, and spontaneous cure rates of IMI were examined.

Results: No difference in percent of new mammary infections was observed between the nosode treated group and the placebo control group. Sample size for evaluation of the mastitis nosode was sufficient to identify a 25% reduction in infections for the treated group. These studies should be considered a starting point for the critical evaluation of alternative therapies used in food animal medicine.

Impacts and Pontential Contributions: The use of homeopathy was documented on a number of dairy and livestock production farms over the course of the study and that information has incorporated into a number of articles and resource materials. To facilitate in the exchange of information, the Alternatives in Animal Health Conference was held in 1997, 1998, and 1999 bringing in numerous speakers on homeopathy, acupuncture, biodynamics, soil health, feed quality, nutrition, whole farm management, and the economics of running an organic dairy operation. These conferences were well attended, but it was requested that we offer workshops throughout the year that can be more advanced and focused on a particular topic instead of brushing lightly over many. In 1998, 1999 and 2000 we organized a number of day long workshops on homeopathy, understanding your soils, getting more acquainted with natural health products, and using herbs for animal health. These workshops were attended by numerous veterinarians, extension and other resource professionals, and producers (both organic and conventional.)

The Northeast Organic Farming Association of Vermont is regarded as the leading state-wide organization in offering technical support for farmers looking into homeopathy and other natural approaches to animal health. This study has contributed greatly to our ability to offer that expertise. Results of this research have been presented at a number of conferences and professional meetings, and two peer-reviewed journal publications are in preparation. This research has benefited producers in providing some understanding of the potential efficacy of homeopathic treatments for mastitis prevention.

Project Objectives:

• To evaluate homeopathic nosodes in the prevention and treatment of bovine mastitis and calf scours

• To compare economics of homeopathic practices and to measure changes in milk quality and yields using homeopathic remedies.

• To document the use of homeopathy on Vermont dairy farms.

• To facilitate information exchange (farmer to farmer and farmer to agricultural professional).

Cooperators

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  • John Barlow
  • Woody Pankey
  • Enid Wonnacott

Research

Materials and methods:

A research project evaluating the effectiveness of nosodes for mastitis and calf scours was initiated in September 1997 with the enrollment of 11 dairy farms, including over 1000 lactating cows and 300 calves. Table 1 contains descriptive information on the original 11 farms participating in this study. The research was conducted by the Northeast Organic Farming Association of Vermont with the collaboration of the University of Vermont Quality Milk Research Laboratory, and was funded under a grant awarded through the USDA Northeast Sustainable Agriculture Research and Education initiative (SARE). The first three months of the project were spent meeting with participating farmers to educate them about the research process. Time was devoted to training of farmers on proper milk sampling and nosode treatment procedures. This was critical to assure compliance by the participating farmers. Ten of the original 11 farms completed the 18 month study period, with farm 3 (Table 1) being removed from the study due to evidence of improper treatment administration and poor milk sampling practices.

Nosode preparation and administration: The E. coli nosode used was a commercially available product from Washington Homeopathics. Farmers that chose to participate in the E. coli study gave newborn calves one of two treatments, the nosode or placebo control which were randomly labeled on each farm as treatment “A”or “B” so that both farmers and researchers were blinded to the treatments given. Treatments were given to all new-borne calves once daily for the first 3 days of life. The calves were assigned alternately to group A or B to assure equal numbers in the treatment and control groups, and in an attempt to randomize treatments. Producers recorded all health problems of the treated calves during the first 3 weeks of the calves’ life.

A mastitis nosode was prepared commercially from common mastitis pathogens isolated from cows within the cooperator herds. Lactating cows in participating herds were stratified by lactation number, days in milk, and composite milk somatic cell count (SCC), prior to being randomly assigned to two treatment groups. Heifers entering the study prior to expected calving date were alternately assigned to a treatment group. Each treatment group was given either the mastitis nosode or the placebo as an aerosol applied to the vaginal mucosa at recommended time intervals throughout the trial. As a double blind experimental design, only the consulting veterinarian who coordinated nosode preparation knew which treatment group received the placebo or the nosode for each farm, and the key to the treatments was maintained in a sealed envelope until the completion of the trial.

The mastitis nosode was prepared from quarter milk samples obtained from cows with clinical mastitis from the participating farms. The milk samples from these individual cases were cultured to identify the pathogen causing mastitis. Thus clinical milk samples were obtained from cows where a single mastitis pathogen was identified to be causing mastitis. The nosode was prepared at a 30C potency from clinically abnormal milk samples where the following mastitis pathogens had been isolated: Staphylococcus aureus, Staphylococcus chromongenes, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, and Klebsiella spp. The following farms contributed clinically abnormal milk samples for the mastitis nosode, (samples were taken November 1997): Staphylococcus aureus, farm 2 and 6; Staphylococcus chromogenes, farm 4 and 9; Streptococcus uberis, farm 2 and 9; Streptococcus dysgalactiae, farm 1 and 4; Escherichia coli, farm 3 and 8; Klebsiella spp., farm 1 and 8 (Table 1).

Treatment procedures: In all cooperator herds, the mastitis nosode and placebo were diluted in a solution of 50% alcohol and administered as an aersol spray applied to the vaginal mucosa of dry cows, lactating cows, and bred heifers. Treatments were administered initially for 5 consecutive days, and then once every two months for the remainder of the study on all animals, plus at calving and at dry off for all lactating animals. Farmers were instructed to manage all animals that developed clinical disease (including mastitis or calf scours) according to established practices for each farm. Farmers were asked to record all disease events, treatments and the outcomes, although no formal criteria and protocols for recording clinical disease events were established in this study.

Measures of efficacy: Effect of treatment on mastitis rates was evaluated by bacteriological culture of milk samples from all cows collected at calving, 30 days post-partum, dry off, the onset of clinical mastitis prior to any treatment, and 30 days following the onset of clinical mastitis. Duplicate individual quarter milk samples were collected aseptically by cooperating farmers. Samples were either refrigerated and delivered to the laboratory within 24 hours, or were stored frozen and delivered to the laboratory with 2 to 3 weeks after collection. Milk samples (0.01 ml) were streak-plated on quadrants of tryptose-blood agar containing 5% washed bovine red cells and 0.1% esculin. Plates were incubated at 37°C for 48 hours and presumptive diagnosis of isolates made. Species identification was by methods recommended by the National Mastitis Council. A quarter was diagnosed as infected by one of the following criteria: (1) both milk samples contained 500 cfu/ml, or more, of the same bacterial isolate; or (2) a clinical sample contained at least 100 cfu/ml of an isolate. Somatic cell counts of all individuals quarter milk samples were determined using a Fossomatic 90. In addition, all herds enrolled in the study were either on monthly DHIA testing for individual cow milk production and composite SCC, or obtained monthly milk production and SCC data by an alternative means.

Differences between treatment groups in prevalence of all IMI, prevalence of new IMI, rates of clinical mastitis, and spontaneous cure rates of IMI were examined. Spontaneous cure was defined as negative for the same species (or a closely related species, in the case of coagulase negative staphylococci) on two subsequent samples. Also, differences in SCC of infected quarters were compared between treatment groups. A modified Student t test was used to compare differences in proportions for prevalence of IMI and spontaneous cure between treatment groups. Control and treatment groups were compared for differences in distribution of cows by lactation number and DIM throughout the study, and for SCC prior to initiation of the treatments. Treatment effects were tested within parities (lactation number) one and two or greater. Differences in SCC of infected quarters between treatment group were examined by analysis of variance.

Differences between treatment groups in average monthly milk production and composite SCC of individual cows was examined by analysis of variance. Season and month of study were considered as dependent variables affecting milk production and SCC.

Clinical mastitis cases were identified by each farmer. Clinical mastitis was defined as the presence of abnormal milk secretions, abnormal swelling of the gland, or both. Clinical mastitis may or may not be accompanied by systemic signs of illness such as loss of appetite or fever. Farmers collected milk samples from all quarters of cows with clinical mastitis, prior to initiation of any mastitis treatments. Farmers or veterinarians treated clinical cases as per commonly practiced on each farm, and all treatments were recorded. The overall and the pathogen specific incidence rates of clinical mastitis were compared between treatment groups on individual farms and on all farms. The incidence rate of clinical mastitis was expressed as number of quarter cases per 1000 cow-days at risk. Only lactating cow days were considered in the calculation of total number of cow-days at risk for treated and control cows on each farm. The number of lactating days at risk for each cow was determined using individual cow DHIA records. Differences in rates of clinical mastitis were tested by Fisher’s exact probability test.

Bulk tank milk samples were collected weekly and frozen for subsequent analysis. Bulk tank milk samples were analyzed by bacteriological culture and somatic cell count. Changes in bulk tank somatic cell count and bacteriology will be examined for the 6 months prior to, for the 18 months during, and for the 6 months following the study.

Research results and discussion:

An abundance of anecdotal information and case histories strongly suggest that homeopathic remedies effectively prevent mastitis. An extensive literature review was conducted to obtain previously published information on the use of homeopathy for the treatment and prevention of bovine mastitis. More then 50 articles were obtained, with the majority being extension advice articles on the use of homeopathy, and few being peer-reviewed publications of controlled trials. To the best of our knowledge, this project involved the largest placebo controlled, double blind clinical field trial of nosode efficacy for the prevention of mastitis among dairy cattle. This study was conducted on 10 different farms that use conventional and organic production practices and ranged in size from 20 to 250 lactating cows. Collaborating farms used a range of management practices, including: intensive seasonal rotational grazing systems feeding strictly grass forages and a small amount of grain for 6 months of the year, and year round confinement systems feeding a total mixed ration to maximize year-round milk production.

One important outcome of this project was the documentation of the use of homeopathic remedies on farms and the development of a resource for more information on how different remedies may be used successfully.

E. coli nosode efficacy: A total of 287 calves were enrolled in this portion of the project. Approximately 6% of all calves were observed by farmers to have scours, and approximately 2.5% of all calves developed scours in the first 7 days of life. No information was available on specific diagnosis of calve gastrointestinal diseases among these calves. No calf deaths due to scours were reported by farmers during the duration of this study, although at least two of the farms had reported historic problems with calf scours associated mortalities. Rate of scours in the nosode treated group did not differ from the control group for either calves with scours at all ages, or calves with scours between days 0 and 7 postpartum (table 2). However, given an apparent low rate of calf scours morbidity and mortality observed in this study, the ability to identify a significant reduction in risk of scours in the treated group may not be practical due to the sample size. Power calculations suggest that with approximately 140 animals per treatment group, and assuming 6% morbidity in the control group, the morbidity of the treated group would need to approach approximately 1% to show significant efficacy of the nosode treatment (95% confidence, 80% power). Conversely, in order to show a significant difference for the observed reduction in all calf scours morbidity of 5.6% for the treated group compared to 6.9% morbidity for the control group the sample size for each treatment group would need to approach 5,600 calves.

Table 2: Summary of E. coli and scour data for all farms combined.

Treatment____Total #_____# calves_______# calves
___________of calves____with scours_____with scours between days 0-7

Nosode______142__________8______________5
Placebo______145_________10______________2

Mastitis nosode efficacy: Rates of new intramammary infections (IMI) among primiparous and multiparous cows treated with the homeopathic nosode did not differ from that of cows in the control group (table 3 and figure 1). These results are consistent with what might be expected if mastitis nosodes function in a manner analogous to that of an autogenous vaccine.

Rates of new infections would most likely be effected by changes in management practices that effect either the prevalence of pathogens in the environment or the susceptibility of cows in the herd. A vaccine administered to a host is likely to have limited effect on environmental prevalence of many mastitis pathogens. For example, the E. coli J-5 vaccine (and similar bacterins commonly used in the dairy industry) has been shown in field trials to have no effect on the rate of new IMI, but to effectively decrease the severity and duration of E.coli clinical mastitis (Hogan et al., 1992). If mastitis nosodes function in a manner analogous to a vaccine, then there may be no effect on IMI rates, however, differences in spontaneous cure rates and rates of clinical mastitis might be observed. Spontaneous cure rates and rates of clinical mastitis did not differ for the two treatment groups. There was no difference found in average somatic cell counts or level of milk production between nosode treated cows and cows receiving the placebo. Based on power calculations it may be predicted that the sample size of treatment and control groups (3200 eligible quarters, table 3) was large enough to identify a significant difference in the quarter level. New infection rate differed between treatment groups by 1.5%, assuming a new infection rate in the control group of 6% as observed in this study. Similarly, with approximately 560 cows per treatment group, and assuming 1.5% of cows with clinical mastitis per month (18% annually) in the control group, the nosode treatment would be predicted to be significantly different from control at a rate of 1.1% of cows with clinical mastitis per month (13% anually) (95% confidence, 80% power).

Mastitis and Milk Quality on organic dairy farms: results of this research have provided evidence of good milk quality on the organic dairy farms in this study. The yearly average Bulk Tank Milk Somatic Cell Count (BTM SCC) for each of the six farms were 212,000, 183,000, 156,000, 59,000, 227,000, and 134,000 cells/ml. The yearly average BTM SCC of the six Vermont organic herds was below the average BTM SCC (336,000 cells/ml) of conventional herds in Vermont that were of a similar size (milking less < 60 cows), and routinely apply pre and post milking teat dips (Pankey, unpublished results of a bulk tank milk quality survey conducted in 1996). Overall, it can be suggested that the organic dairy farms in this study are shipping a high quality fluid milk product.

Results of this research have provided data on the prevalence and incidence of mastitis on organic dairy farms. Analysis of this data suggests that a number of the organic dairy herds have challenges with elevated individual cow somatic cell counts, and these cases of chronic subclinical mastitis are frequently caused by Staphylococcus aureus and Streptococccus uberis. Clinical mastitis caused by these two pathogens is also a problem on these farms. One hundred and twenty-six cases of clinical mastitis were reported by the six farms, for which 109 quarter samples were submitted in duplicate for bacteriological culture. Staphylococcus aureus and Streptococccus uberis were the predominate species causing clinical mastitis on these farms, resulting in 31% and 28 % of all cases, respectively. Fourteen cases of mastitis (11%) were identified during the dry period on three of the farms (the remaining three farms did not report having observed clinical cases during the dry period). Dry period infections were caused by the following bacterial species: Staph. aureus, 4 cases; Strep. uberis, 5 cases, mixed infection of Staph. aureus and Strep. uberis, 1 case. These findings are consistent with those of Vaarst and Enevoldsen who described Staph. aureus and Strep. uberis, as the predominant pathogens causing clinical mastitis on 14 Danish organic dairy farms. We also observed a similar proportion of coliform mastitis cases (7%), although we obtained a lower proportion of Strep. dysgalactiae (2% of cases compared to 9% in the Danish study), and fewer cases of bacteriologically negative clincial mastitis (16% of cases).

Differences were observed in predominant types of pathogens causing clinical and subclinical mastitis on the conventional confinement housed dairy operations compared with the organic herds and pasture based herds in this study. A larger proportion of infections caused by environmental pathogens (such as Coliform bacteria and Streptococci other then Strep. agalactiae) was observed in the confinement housed cattle in this study. While such comparisons are based on a limited study population, they are supported by previous research indicating reduced incidence of environmental mastitis in intensively grazed dairy herds. These results are also consistent with reports of the increasing importance of controlling environmental pathogens among confinement herds that have controlled contagious pathogens such as Staphylococcus aureus. The differences observed in the proportion of infections caused by some species of bacteria on the organic and conventional herds in this study suggest that these groups of herds have unique factors which influence mastitis prevalence. The lower proportion of infections due to Streptococci and Staphylococci on the conventional herds (75% of infections versus 97% on organic herds) may be associated with a number of factors, including predominant type of bedding used, impact of type of housing and stall design, and use of dry cow therapy. Similarly the increased proportion of mastitis caused by coliform bacteria among the confinement housed cattle (25% of infections versus 3% on organic herds), is likely related to environmental issues associated with housing, as well as the control of contagious pathogens such as Staphylococcus aureus. These differences may provide some clues to support recommendations on mastitis control practices which are directed at control of specific pathogens on individual dairy farms.

Mastitis Treatment Practices on Organic Dairy Farms in Vermont: Hovi and Roderick described the types of mastitis therapy on organic farms in the U.K. Homeopathy was frequently used as an alternative to antibiotic therapy on organic farms in the U.K., but these authors also reported that antibiotics were used for mastitis treatment on organic farms for approximately 41% of the cases. Analysis of treatment records, from January 1998 to June 1999, indicated that antibiotics were used for the treatment of 5 (4%) of 126 mastitis cases recorded on the six organic farms in Vermont. In two cases, intramammary dry cow therapy was used for the treatment of clinical mastitis identified during the dry period on one farm, and in three cases, on a second farm, intramammary or parenteral antibiotics were used for treatment of acute coliform mastitis in cows with systemic signs. Homeopathy was frequently used on five of the six farms described in this report. The remaining farm used homeopathy intermittently. Other therapies used to treat mastitis included: oral and parenteral non-steroidal anti-inflammatory agents (aspirin or banamine), topical udder liniment (occassionally), parenteral vitamin E and Selinium, Vitamin C, and Vitamin B-complex. A number of farmers frequently dried off quarters or culled individual cows following observation of chronic clinical mastitis, especially in cases where Staph. aureus was identified by bacteriological culture.

Many farmers in this group reduce the somatic cell count of salable milk by keeping high somatic cell count milk of individual cows out of the bulk tank. They achieve this by using quarter milkers to divert high SCC milk from chronically infected quarters. Another practice that has been adopted by these producers is to use problem cows with high somatic cell counts as “nurse” cows to raise a group of calves. The potential impact of this practice on prevalence of mastitis (and other diseases) among heifers at calving should be considered for future study.

Organic dairies face milk quality and mastitis challenges that require thorough and consistent implementation of teat sanitation and milking time hygiene practices. In addition, maintenance of a clean and dry cow environment is critical. The producers involved in these studies have benefited from the experience of using individual somatic cell count and mastitis culture information to identify problem cows and pathogens of concern on individual farms. Organic certification processes mandate excellent record keeping and promote the frequent review of records to monitor trends on the dairy. Staphylococcus aureus and Streptococcus uberis have been identified as the primary pathogens causing clinical and subclinical mastitis on organic dairy farms. While the limitations imposed by the prohibition of antibiotic use for the treatment of mastitis, (especially with regard to restrictions on the routine use of dry cow therapy), can not be completely overcome by strict adherence to superior teat sanitation and milking time hygiene practices, the success of some organic producers in their ability to limit mastitis through management should serve as a motivator for other producers to achieve a comparable or better level of udder health.

Insights into the Homeopathy Research Design: It was Dr. Woodard’s and Dr. Sheaffer’s opinion (consulting veterinarians for the study) that high production herds that were on a heavy vaccination program, managed with Bst, hormones and antibiotics would be less likely to respond to the nosode treatments.

Another concern expressed by a few veterinarians and farmers experienced in the use of homeopathy was that a reductionistic scientific design would not be successful in measuring the effectiveness of a homeopathic remedy. One of the participating farmers pointed out, “since we know so little about how homeopathy works, is it possible that the cows getting the placebo are actually getting ‘treated’ by the other cows just by rubbing noses, sharing the same space, grazing the same ground?” “There is so little that we know about how homeopathy works. Is it possible to study its effects in a conventional, reductionist design when it may work in a more holistic, energetic way?” How do you measure such effects? Why look at bacteriologic outcomes, when homeopathy may be acting in a more holistic way?

Participation Summary
No milestones

Project Outcomes

Impacts of Results/Outcomes

Results of the research trial have been presented at two national conferences. Preliminary results were presented at the Mastitis Research Workers meeting in Chicago, Illinois, November, 1999. Results of the project were also presented at the Alternative and Herbal Livestock Health conference, Storrs, CT, October, 2000. An abstract has been accepted for presentation of results of this research at the Second International Mastitis and Milk Quality Symposium, scheduled for September 13-15, 2001 in Vancouver, British Columbia. A total of three manuscripts are being prepared as a result of completion of this project. A manuscript entitled “Evaluation of Homeopathic Nosodes for Mastitis and Calf Scours: Lessons from the Vermont Nosode Project” has been submitted for publication in the American Journal of Alternative Agriculture. A manuscript entitled “Field Study Evaluating Homeopathic Nosodes for Mastitis Prevention” is in preparation, and will be submitted to a peer-reviewed journal such as the Journal of the American Veterinary Medical Association, or the Veterinary Record. A manuscript entitled “Prevalence and incidence of mastitis on organic dairy farms in Vermont, USA” is in preparation, and will be submitted to a peer-reviewed journal such as the Journal of Dairy Science.

The use of homeopathy was documented on a number of dairy and livestock production farms over the course of the study and that information has been incorporated into a number of articles and resource materials. To facilitate in the exchange of information, the Alternatives in Animal Health Conference was held in 1997, 1998, and 1999 bringing in numerous speakers on homeopathy, acupuncture, biodynamics, soil health, feed quality, nutrition, whole farm management, and the economics of running an organic dairy operation.

Workshops were offered in 1998, 1999 and 2000 allowing for a more in depth look at homeopathy and its practical use. These workshops were set up on a host dairy farm where the speaker would spend the morning discussing homeopathy, herbs and other alternative practices and the second half offered an opportunity for a hands-on application of what was learned. An average of 40 people attended each of these workshops followed by a technical article covering the workshop (see appendices). Written materials were submitted in the NOFA-VT NOFA-Notes newsletter , the NOFA-VT Dairy Tech Newsletter or one of the local agricultural magazines. People attending these technical workshops were veterinarians, Extension, other agricultural resource agencies, and farmers both conventional and organic.

The Northeast Organic Farming Association of Vermont is regarded as the leading state-wide organization in offering technical support for farmers looking into homeopathy and other natural approaches to animal health. This study has contributed greatly to our ability to offer that expertise. This research has benefited producers in providing some understanding of the potential efficacy of homeopathic treatments for mastitis prevention.

Economic Analysis

Results of this research document methods of milk production and dairy cattle husbandry which limit mastitis and ensure the production of quality fluid milk products. Producers involved in this research realized the financial benefits of using individual somatic cell count and mastitis culture information to identify problem cows and pathogens for mastitis control on individual farms.

Research has documented how clinical mastitis negatively affects total milk yields and milk quality. In this study, it was anticipated that comparisons of Somatic Cell Count (SCC) and milk yield by treatment group would show an economic difference. There was no significant difference between treatment groups to do this comparison and the SCC was so low on each farm that it would have been difficult to determine any gains or losses in volume.

In looking at the costs of using homeopathic remedies for the treatment of mastitis, Dr Edgar Sheaffer performed a study comparing the costs of mastitis treatments in 1990 and 1998 (table 3). Choices of treatments were antibiotics, penicillin, a more expensive drug, or a homeopathic remedy. Both time periods indicate that the homeopathic treatment was less expensive.

Areas needing additional study

1. The potential effect of using Staph aureus vaccination programs to prevent mastitis on organic dairy herds should be evaluated.

2. The potential impact of using cows subclinically infected with mastitis pathogens as nurse cows to raise calves.

3. The prevalence of mastitis (and perhaps other diseases such as Johne’s disease) among heifers at calving should be considered for future study.

4. Upper respiratory problems contribute to a large percentage of illnesses and mortality for young animals (lambs, calves, piglets). Can run a comparison using a placebo, homeopathic remedy and antibiotic.

5. Feeding mastitic milk to calves can make calves more susceptible to mastitis when they are adults. Important to feed colostrum milk to calves from cows that are Johne’s-free and mastitis free.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.