From the May/June issue: Practices focused on prevention could apply elsewhere.
Like most veterinarians managing the heath programs for large dairies, Juan Velez, MV, MS, ACT, wants to see good, solid clinical data before adopting any practice or product. But as executive vice president of Aurora Organic Dairy, he needs to avoid some proven products and seek alternatives, with an intense focus on disease prevention.
The same applies to Guy Jodarski, DVM, who serves as supervising veterinarian for Organic Valley, a cooperative of organic farms in 34 states. He stresses management-based prevention rather than unproven natural remedies, while testing practices that could fit within the various sizes and environments of cooperating dairies.
Focus on prevention
Aurora Organic Dairy began in 2003 with one dairy near Platteville, Colo. The operation since has expanded to include two more dairies in Colorado and one in Texas, milking a total of 18,000 cows.
Organic dairies must focus on prevention, Velez says, adding that good conventional dairies use many of the same preventative measures.
In organic production, Velez says, the veterinarian needs to adopt a different mindset and encourage the same priorities with the herdsman and other crew members. Instead of developing standard operating procedures for antibiotic treatments, for example, he works with the crew in establishing cleanliness scores and locomotion scores, and in using those scoring systems to conduct routine internal audits. These audits allow him to track the overall well-being of cattle and make appropriate decisions based on trends.
These types of consulting functions, he says, offer opportunities for veterinarians to apply their skills and become more involved in the total management of the operation.
Grazing, outdoor access and forage-based nutrition
The USDA organic program requires a minimum of 120 days on pasture, and both veterinarians believe the more grazing the better. Nutrition plays a critical role in animal well-being and disease prevention, Velez stresses. With restrictions on a number of feed additives, he says, the key is to provide a well-balanced forage-based diet year-round.
During the growing season at Aurora, from late April until September, the cows move to irrigated grass pastures surrounding the dairy, where they move through a series of paddocks in an intensive grazing system.
During the cold season, cows reside in free-stall open drylot barns with deep sand bedding, all with access to exercise lots the cows can use any time. Velez believes these facilities help minimize incidence of lameness. Rations include grass hay, alfalfa, sorghum or corn silage, and a grain mix including wheat, soybean meal, corn and soy hulls and a mineral package.
Likewise at dairies in the Organic Valley cooperative, outdoor grazing and exercise are key components of the overall health program. For parasite control, Jodarski says keeping calves on milk longer than typical, coupled with pasture rotations, minimizes problems. Calves receive two milk feedings of 1 gallon per feeding daily for the first two months, and some of the dairies leave calves with their dams for part of the day for two months, accepting some reduction in milk production.
Many dairies begin grazing calves on pasture from day 1, and most calves receive virtually no grain in their rations until weaning. Jodarski believes managing dairy calves more similar to beef calves, on forage and milk, results in a higher rumen pH, helping minimize coccidiosis, develop the rumen and generally improve immunity.
Facilities vary widely among the over 1,500 cooperating dairies, many of which are small operations. Ventilation in barns is not always optimal, so Jodarski encourages managers to correct ventilation deficits and keep the cattle outdoors as much as possible.
Jodarski stresses the biological relationships between soil fertility, forage quality, nutrition and animal health, and works to develop grazing systems that capitalize on those connections.
Velez says hoof trimming plays a vital role in lameness prevention, and Aurora regularly brings in a well-regarded lameness expert, Iowa State University’s Jan Shearer, DVM, MS, to help train the dairy’s hoof trimmers and refine the operation’s lameness-prevention program.
For infectious hoof diseases associated with lameness, Aurora employs a standard operating procedure for regularly running cattle through copper sulfate foot baths, including an acidifying agent to keep the solution in the proper pH range and improve its effectiveness.
Jodarski recommends a high forage diet to prevent rumen acidosis, trace mineral balance to maximize foot immunity and exercise from grazing for foot and leg health. Many dairies intensively grazing their cows no longer require regular hoof trimming.
Dry cows, reproduction and heifer development
Initially, Velez says, he was concerned about not being able to use antibiotic treatments in dry cows, but has found that good dry-cow management and milking routines can protect udder health and milk quality in the fresh cow. This summer, he says, the team at Aurora and University of Minnesota veterinarian Sorge Ulrike will test a system of milking cows one time per day for the first week of the dry-off period, while feeding a ration of good grass hay and plenty of fresh water. Research at the University of New Hampshire, he says, has shown this system can benefit udder health in dry cows and reduce masititis. The process takes more time and pen space but pays in an organic system.
Jodarski says the dairies in his program generally dry cows off at once. Most cows in late lactation are relatively low-producing, milking less than 40 pounds per head per day, so the transition at dry-off is easier. About 30 days prior to dry-off, he recommends dairies test all four quarters for mastitis or high somatic cell count (SCC) and address problems before dry-off. All cows are checked at five to seven days following dry-off for heat or swelling in the quarters and are milked or treated as needed.
When toxic puerperal metritis does occur in fresh cows, Velez says a natural treatment called “Uterflush,” which is approved for organic production, has been shown to be efficacious in Aurora studies in cooperation with a Texas A&M researcher. It is not as effective or fast-acting as antibiotic treatments but favorable in comparison to no treatment.
Research at Ohio State University, he adds, has shown that uterine infusion with a dextrose solution can serve as a viable alternative to using prostaglandin and antibiotics to treat post-partum uterine infections, significantly improving pregnancy rates in affected cows.
Velez also has reviewed research results and conducted in-house trials on an herbal mastitis tube. The product shows some potential he says, but results have been inconsistent. So until he sees stronger data, and federal approval, he is holding off on using the product.
In an organic system, any animal that needs to be treated with antibiotics or other unapproved products leaves the dairy. When heifer calves require treatment, Aurora typically pulls them for immediate sale to a neighboring conventional dairy. Most calves and cows respond well to treatments approved under the program, he says, but those that do not are culled and treated quickly. Cull rates on the dairy are similar to those on conventional operations, but animals are culled sooner. The USDA organic rule, Velez notes, prohibits operations from withholding appropriate treatment when needed for animal well-being.
Jodarski adds that an organic program allows supportive care such as dextrose and calcium solutions, electrolytes for dehydration and flunixin for toxic shock. The tranquillizer xylazine, analgesic butorphanol and local anesthetic lidocaine are allowed (with extended withdrawal times) for humane handling during surgical intervention and for pain management. In addition, there are herbal and natural remedies available for treating infections and other conditions. Good preventative care minimizes the need for these materials.
Vaccination, immunity and diagnosis
The USDA Organic Program allows vaccination, and it plays a critical role in organic dairies. Jodarski encourages cooperating dairies to work with their veterinarians to build effective vaccination protocols, monitor animal health and conduct post-mortem examinations as needed.
Velez says he has developed a trusting relationship with a technical services veterinarian with a leading animal-health company. Through that relationship, the dairy staff receives regular training on handling and use of vaccines, annual review of protocols and honest assessment of which products are working or not.
Velez also stresses the importance of good nutrition and a low-stress environment in supporting the vaccination program. Animal welfare is vital, he says, and the dairy has used third-party certification through the Validus program since 2005.
In terms of genetics, the Aurora operation focuses selection on longevity traits such as sound legs and reproduction, rather than on high production. All their AI sires are polled to reduce horn-related injuries in the herd. Less emphasis on milk production allows the dairy to use more polled genetics than most conventional dairies.
Aurora uses an electronic activity-monitoring system for heat detection, since typical estrus-synchronization products are not allowed in the organic program.
The Organic Valley dairies also encourage use of polled genetics and dehorn calves early when needed. They generally select for health traits, good udders and milk components, as well as sound legs, strength, depth and rumen capacity — grazing traits — rather than for high milk production. Some use Scandinavian Red cattle, selected for health and longevity, in crossbreeding programs. Many of the smaller cooperating dairies use natural-service bulls.
Comparable herd health
No class of dairy — organic or conventional, large or small — holds a monopoly on good health or animal well-being. There are good and bad examples among any group, but either system can produce good results. The Aurora operation maintains a SCC of 150,000 or better company wide. The cooperative average SCC for Organic Valley dairies has moved from about 250,000 five years ago to under 220,000 for 2013.
Velez notes that in 2012, University of Wisconsin veterinarian Pamela Ruegg led a team of researchers from Wisconsin, Cornell and Oregon State University in a research project comparing herd health and milk quality on organic and conventional dairies. He says organic proponents generally believed the studies would show better health in their systems, while skeptics expected to see better health in conventional production. It turned out that herd health and milk quality were generally similar in the two systems, although production is considerably higher in conventional dairies. Organic dairies included in the study maintained equal levels of milk quality, reproduction and culling as conventional herds without the use of antibiotics. Longevity was slightly better for the cows in organic herds. The research reports are available in the organics section at milkquality.wisc.edu.
See this article and features on trichomoniasis, the precautionary principle, vitamin A deficiencies, electrolyte therapy and a new approach to bovine veterinary practice in our May/June issue.