by Elizabeth A. Tomlin
Quality and safety of raw milk and groundbreaking analysis technology for detecting illness in dairy cows before physical evidence appears were topics focused on at CNY’s 2018 Dairy Day.
Speakers included CNY CCE Regional Dairy Specialist David Balbian; Dr. Heather Dann, Research Scientist at Miner Institute; Nicole Martin, Cornell University Associate Director for Milk Quality; and Dr. David Barbano, 2018 National Cheese Institute Laureate Award winner, Food Scientist/Researcher, Cornell.
Nicole Martin reported that research concerning spores in raw milk is ongoing at Cornell.
Spores develop through bacterial evolutionary strategy where mutations occur for self-preservation, allowing them to survive environmental situations designed to eliminate them.
Martin reported that these spores are heat resistant and cold resistant, surviving normal bacteria destruction methods, including sanitation, pasteurization, drying and radiation.
After these methods are used, persistent spores become active again, following a cycle of rapidly dividing, multiplying and growing again. Higher counts of these bacteria cause spoilage.
Martin identified classifications of specific bacteria, showing that several varieties of spore-forming bacteria — including Bacillus, Paenibacillus and Lysinobacillus — are able to survive.
Some spores affect fluid milk storage and shelf life, while others affect cheese.
Martin noted that with cheese, spores may not become active until six months into the aging process.
In milk powder, bacteria impacts international export market prices, due to lower quality.
This creates an enormous economic impact.
So how are these spores getting into bulk milk tanks?
“Where are they coming from? How are they getting into the milk? How can we prevent them from getting into the milk?” Martin asked.
She said “millions” of plate tests and studies have been done regionally and nationally, trying to determine the answer to these questions.
Emerging data over the past few years show that many environmental factors impact spore counts and contamination.
“What we know is that spores are environmental contaminants.”
Studies found “very high levels” in feeds (TMR and silage), bedding (new and used), towels, water, manure, parlors and equipment.
“Pretty much everywhere,” Martin emphasized.
An interesting fact determined through these studies showed that cows with docked tails have a lower incidence of spore counts.
Although Martin remarked that these studies are ongoing, areas of focus for farmers include paying closer attention to udder cleaning (including teat ends), changes in towels and sanitation procedures. These areas are being closely investigated.
Another area being studied is regarding biofilm formed by some bacteria in milking and processing equipment that may cause contamination of the milk.
“Processors are very concerned about spores coming from the farm,” Martin attested.
“Expect buyers to have high standards,” commented Balbian.
New milk analysis tools were reported on by Dr. Barbano and Dr. Dann.
Barbano described ‘new tools’ developed in milk analysis for bulk tank and individual cow milk that will impact decision making for management of feeding, health and reproduction in dairy cows.
“Now, instead of just getting various aspects like the fat and protein in milk, we’re getting a more complete fingerprint of each milk sample,” explained Barbano.
Information about each cow is hidden in that “fingerprint of her milk.”
Barbano remarked that each cow, individually, contributes to the bulk tank and the question is how to figure out what that individual cow needs to produce at her optimized performance level.
“Each cow needs to be a cow of interest,” Barbano said.
Analysis tools are currently being developed that will provide information on individual cows.
Relatively new information available on bulk milk data reports contains information about milk fatty acid data.
“This is something we hope will be spread across all of the bulk tank testing,” said Barbano.
Although technologies are still being developed that will assist farm managers in detecting information on individual cows, Barbano said the vision is in place and much has already been developed.
On 430 farms, infrared milk analysis was used to test for components and fatty acid composition, breaking it down into three components: De novo, preformed, and mixed-origin.
Barbano explained that the three components are molecules of fat composed of different structures.
De novo, which means made from within, can make up to about 30 percent of the structure and, according to studies, shows a strong link to high components in those molecules.
Barbano said new metrics give him insight and allow him to view the balance of these components and see how they respond according to a variety of variables, such as the stage of lactation in the cow or changes in feed. How well feed is digested, how well the rumen is working or responding to diet are reflected in the components. Environmental changes also stimulate a reaction.
“The strongest correlation between milk fatty acid composition and the concentration of fat and protein in milk was with de novo fatty acids production,” Barbano reported.
De novo fatty acid synthesis seems to be related to the efficiency of forage and rumen function; working through each mammary cell in the udder and obtaining rumen fermentation from digested forage resulting in building amino fatty acids.
This may give farm management opportunity in the future to produce an increase in output of fat and protein per cow/per day, through improving the synthesis of de novo fatty acids.
“You really need to develop hardware and software to break this approach into your milking system,” said Barbano. Eventually a sensor will be developed that will provide information including data and interpretation for each cow.
Future vision for this analysis includes “individual cow, real-time milk testing for precision farm management of feeding, health, and reproduction.”
At this time, analysis is used in the bulk tank at the full herd level and for milking group diagnostics.
In addition to analyzing components in milk, Barbano also reports the ability to pick up on impending cow illness, siting documented cases of detection before physical signs were evident.
“This is a real team effort,” Barbano emphasized, acknowledging St. Albans Cooperative, Dr. Rick Grant and Dr. Dann of Miner Institute, who’d collaborated with Barbano on much of his studies.
Dann spoke to attendees about using milk fatty acid metrics as a guide to make better on-farm nutritional and management decisions.
“There is value in milk analysis,” said Dann, explaining that milk analysis is used worldwide for improvement in profit with dairy herds.
“Typically,” said Dann, “the goal is to use milk fatty acid metrics to make decisions on-farm to increase milk fat and protein yield. Farmers and their consultants that receive milk fatty acid metrics regularly look for trends over time. The data can indicate rather quickly that an unexpected change occurred or indicate the response to a planned change.”
The analysis can also be used as a method of troubleshooting when milk fat has decreased.
Dann said milk fatty acid metrics is “one piece of the solution and another tool for your toolbox.”
Contact Dann for milk testing information; or
“This is a new view into milk,” Barbano stated. “The challenge and opportunity are there.”