Dr. Rob Farruggio had a frustrating case on his hands. In 2010, the Jefferson, Wis. veterinarian was working with a 100-cow dairy with a severe calf scours problem.
"These clients were experiencing 50% scours incidence in their preweaned calves, and had a 25% scours-related death loss," he said. "They raised only their heifer calves, so they were losing one-quarter of their herd replacements."
Despite efforts to curb the problem with excellent colostrum delivery, nutrition, milk-replacer mixing, dry-cow and calf vaccinations and feeding a charcoal-based binding additive, the situation did not improve. Farruggio's conclusion: Sanitation must be the culprit.
"I started researching restaurant and food-processing systems and learning more about their sanitation methods," he said. "We expect the food we eat to be clean, and we should expect nothing less for our calves. What I found was we were feeding dirty milk to the calves."
Kris Follmer, Operations Quality Manager for Milk Products, LLC, Chilton, Wis., has made similar connections between human food processing and calf nutrition and rearing. His career began in the food industry, and now employs similar sanitation methods in both milk replacer manufacturing and on-farm education and monitoring.
Despite routine washing efforts, Follmer explained, equipment appearing visually clean actually may be quite unsanitary, due to the accumulation of biofilm. This substance consists of densely packed communities of cells that can grow on any surface where moisture is present, including buckets, hoses, nipples, bottles, pasteurizing equipment and esophageal feeders.
Once the communities are established, they emit a protective outer layer, insulating them from contact cleaning efforts. Virtually no surface is immune to biofilm: It can accumulate on stainless steel, plastic, aluminum, rubber, copper and brass.
If you've ever felt a slimy surface inside a calf bottle or pail, that's biofilm. The interior walls of water troughs also are frequent biofilm sites. Follmer provided another common location: "If you miss a few days of brushing your teeth and feel those slimy ‘sweaters" developing on the outside, you've created a crop of biofilm," he said.
Gentle rinsing and ordinary sanitizers do not provide enough turbulence to get rid of biofilm. "We are not able to maintain good dental hygiene with just swishing water or mouth rinse over our teeth," Follmer explained. "It takes physical action to break up biofilm, whether it's on our teeth or on calf-feeding equipment."
Chemicals help, too
In his quest to help clients improve calf-equipment sanitation, Farruggio regularly shares the basic characteristics of the different types of chemicals used for on-farm cleaning:
- Disinfectants – Products applied directly to an object to destroy or irreversibly inactivate pathogenic microorganisms and some viruses.
- Sanitizers – Products that reduce the number of (but do not destroy) microbial contaminants on surfaces to levels that are considered safe.
- Detergents – Products that serve to disperse and remove soil and other organic matter from surfaces, allowing disinfectants to reach and destroy microbes.
The veterinarian suggests the best calf-equipment cleaning protocols incorporate all three of these types of chemicals – or at least a detergent and disinfectant – in addition to adequate drying of surfaces.
Follmer concurred, noting, "Bacteria must have water to grow. Any surface that is dry will not promote growth."
The four factors contributing to the effectiveness of cleaning chemicals are (1) concentration; (2) contact time; (3) temperature; and (4) mechanical action. "The fourth point is critical," said Follmer. "There's no substitute for elbow grease."
Follmer suggested quaternary ammonia as an excellent on-farm disinfectant. A favorite of Farruggio's is chlorine dioxide, which is 2.5 times more oxidizing than bleach, very affordable, and highly effective at infiltrating biofilm. He cautioned the product does have a low boiling point (51.8˚F). It should be stored in the refrigerator.
All products must be used according to manufacturer's instructions and safe handling procedures.
Sanitation audits reveal truth
Both experts embrace the use of bioluminescence to detect the presence of biofilm. Follmer explained that all living cells contain a substance called Adenosine Triphosphate (ATP). It is the primary energy transferring molecule of live cells, and its presence is an indication of living cells, versus strictly organic matter.
In on-farm evaluation using the technology, small swabs are used to sample various equipment surfaces. The swabs are combined with a chemical reagent that includes an enzyme produced by fireflies. ATP reacts with the enzyme and produces light, the brightness of which is determined by how much ATP is present. The swab is inserted into a hand-held unit called a luminometer, in which ATP levels in the sample are measured.
The technology is affordable and provides quick results. Best of all, the information can be used over time to track progress in on-farm cleaning methods. Farruggio does a baseline sample set when he starts the equipment-cleaning education process with a client, helping identify areas needing attention.
Depending on the farm's existing practices, he might suggest changes in chemical products; more frequent cleaning; increased physical brushing and scrubbing; and/or changes in water temperature. He said it takes about three weeks to break through existing biofilm. If protocols continue to be followed correctly, the readings should remain considerably lower.
Farruggio believes every farm raising calves can benefit from a similar sanitation audit and subsequent improvement process. Many milk-replacer suppliers, dairy chemical dealers and veterinarians now offer them. Even if the herd veterinarian is not the person performing the audit, Farruggio encourages veterinary involvement, because the process can have such a significant impact on animal health.
"Once a new set of cleaning protocols is in place, I use the swabbing tool as a friendly reminder, making random checks from time to time when I'm visiting a farm," he said. "Most of my clients actually think it's pretty fun to have these surprise checks. They want to see how they're doing, and have witnessed the impressive results that improved equipment cleaning methods can have on calf health and performance."
One of those clients is the herd that, five years earlier, was struggling with half of their calves experiencing scours. Today, with improved equipment cleaning and regular monitoring, they are down to 5% scours incidence, and virtually 0% scours-related death loss. They've discontinued feeding the charcoal-based binding additive, for a savings of $15.00 per calf, and are much more optimistic about the future of their herd.
"Having the ability to not only more effectively clean equipment, but nearly instantaneously measure the results of those practices, has helped many herds make great strides in calf health," said Farruggio. "It has become a very gratifying way to assist my clients."
Garden hoses: bacteria hot spots
When your mother told you not to drink from the garden hose, she probably was right.
These seemingly innocent, on-farm equipment staples actually can serve as a haven for live bacteria. Wisconsin veterinarian Rob Farruggio routinely sees luminometer readings over 4,000 from swabbed samples from the interior of garden hoses – a number literally "off the charts" in terms of acceptable live bacterial load.
"We think of a hose as a closed system, and we're only running water through it, so it's hard to believe it can be so easily contaminated," he said. But any small crack or micro fissure can allow bacteria to enter, and simply allowing the end of a hose to touch the ground also invites bacteriain. Once inside, it sets up camp encased in biofilm and continues to multiply in an ever-moist environment.
If a bacteria-laden hose is used to transport water for delivering calves" drinking water; mixing milk replacer; or cleaning housing areas, it's easy to see how it becomes a disease transport vehicle.
Farruggio said cleaning and disinfecting garden hoses probably is not as practical as simply replacing them every 3 to 6 months.