Mycoplasma, The Lurking Menace

Every few weeks I receive a phone call, email, or a FAX from someone in the US with a goat kid (dead or alive) with a diagnosed case of mycoplasma. They find me through finding online an article I wrote in 2008 about our experiences with the disease. I am sharing the article again here along with an added Q&A section that follows the article. I based the Q &A on the most common questions I get from these folks. I always remind people, of course, that I am not a veterinarian, but as many have found out, just because you are consulting a licensed DVM does not mean that you will get all of the correct answers. Still, you should always work with a vet you trust and that will do some research and stay current with updates regarding the disease. There, enough disclaimers!  Here is the old article:

Mycoplasma: This Time it’s Personal!

By Gianaclis Caldwell

Appearing in Dairy Goat Journal, Volume 86 Number 6, Nov/Dec 2008

 Authors Note:  The author is not a veterinarian. All references to medications used in this article are for reference only as they relate to the author’s personal experience.  Please consult a licensed veterinarian when dealing with this or any other medical problem.

Mycoplasma is one of those diseases that most goat owners have heard of, but may not be able to tell you much about.  Like so many problems, until it threatens your own animals, it remains a word in a book, a definition waiting to be looked up.  Unfortunately, I know a lot more about mycoplasma than I would like to known thanks to the pathogen calling on our herd in the spring of 2005.

 Before I tell the story of our own loss and learning, let me give you a short course on mycoplasma.  I would first like to reassure you that mycoplasma is not the killer that it once was. The microorganism has apparently lost much of its virulence. Also, it poses no threat to humans, either in the milk or via the carrier animal. So please read on without too much trepidation!

Mycoplasma – In a Nut-Shell

Mycoplasmas are simple microbial organisms (not true bacteria or viruses) that lack a true cell wall.  While this makes it sound as if they should be easy to be rid of unfortunately they are not.  Most antibiotics work by attacking the cell wall, thus destroying the microorganism.  Since mycoplasmas do not have a cell wall, not as many antibiotics are effective against them.

There are many members in the mycoplasma family.  The most common typically cause mastitis and respiratory problems.  Many animals never sicken after exposure, but remain capable of passing the pathogen to their offspring in their milk (the most common route of transmission). While many adults can remain asymptomatic, kids, especially those under stress, are the most susceptible to becoming ill after exposure.

Another problematic aspect is that there are no laboratory tests that guarantee your animals are mycoplasma free. The pathogen is capable of lurking undetected within an asymptomatic host.  Unless an animal is “shedding” during the test your results will be negative. So while you may never have had any animals ill or with symptoms of mycoplasma, you cannot kno w for sure that your herd is mycoplasma free.  Only when symptoms appear AND are tests are done specifically for mycoplasma will you know.  Not a very cooperative little pathogen, is it?

The Stealth Killer

Even when an animal has symptoms that might be indicative of mycoplasma, it could easily be a bacterial or viral problem- and more often than not it will be.  So you might treat the animal for what you think is pneumonia, joint-ill, or bacterial mastitis.  The animal recovers and you never know that it might have been mycoplasma.  Here’s an example using one kid with 3 different treatment approaches:

Scenario 1: A six week old wether kid goes off his feed.  You watch him, he looks okay so you wait until the next morning. You take his temp.  It is 105.3. You give him a little Banamine (a pain killer, and fevere reducer) and check your antibiotic stock.  If you are like most of us, you have LA 200 or Biomycin (both are oxytetracyline) on hand.  You double check the dosage for this age and weight and start him on a course of treatment.

He is still taking his bottle, although with less than a kid’s usual vigor, and his temperatuire is dropping. He doesn’t like to stand up, but you figure he is just feeling poorly. By the next day, the antibiotics and Banamine seem to be helping. His temp is down and he is back to eating well.  You figure he had a touch of pneumonia.  You continue with the oxytetracycline and he recovers completely, never having any more problems.

Scenario 2:  Your six week old wether goes off his feed.  You watch him and he looks okay, but the next morning he looks a little listless.  You take his temp, it is 105.3.  You give him a little Banamine and call your vet.  You also notice that he doesn’t seem to want to stand up.  After closer inspection, you see that his knees are a bit swollen, or is it your imagination?- they are not soft and squishy, and he is very fuzzy.  You mention all of this to your vet who suspects joint-ill (an infection that enters through the newborns umbilical cord). Even though you dipped his cord right after birth the vet says that it can still happen.  So he starts the kid on Naxcel (a newer, powerful antibiotic) and has you continue the Banamine.  You have the little guy in your house to watch him closely and keep him taking fluids.  By the next day, you think he is getting better, as his temp. is within normal at 103.2.  But he isn’t eating and seems so uncomfortable.  You keep up the antibiotics.  He won’t stand at all by the end of the day and it is obvious the joints are tender. If you bend his knees for him, he cries out in horrible pain.  That night, his temperature plummets, and he dies in your arms.

You are horribly sad, but know you have done all you can.  You let your vet know. He suggests a post-mortem joint fluid culture taken to rule out other possibilities.  He asks if the dam has had mastitis.  She hasn’t, so he suspects a bacterial infection which led to polyarthritis.  The cost for the culture is high, you don’t want to haul this dead kid to the vet, you have no other symptoms in your herd, so while you feel bad, your budget dictates that you pass on the cultures and bury him.

Scenario 3: A six week old wether kid goes off his feed a bit.  By morning he looks worse, so you take his temperature.  It is a elevated at 105.3.  He also seems a bit stiff when he moves.  You decide take him to the vet. The vet gives you the possible causes after she notices that his knee joints are tender.  One possibility is bacterial polyarthritis (also known as joint-ill), which she thinks is the most likely cause, even though his cord was properly dipped at birth. Since you have no mastitis in your herd, mycoplasma is not her first suspect.  But just to be sure, you decide to go ahead and have a joint fluid sample taken.  It is painful for the kid and you feel badly about the potential cost.  The vet shows you the fluid under the microscope it is obviously filled with pus, as it would be for bacterial polyarthritis.  You and the vet decide that a sample should be sent to a lab for culture, just to be sure.  The vet starts the baby on oxytetracyline (which is effective against mycoplasma) and sends you home with some Naxcel as well to switch to if he doesn’t improve.  The culture will take 7-10 days.     Fortunately the kid improves within a day or two. The bill is 250.00.

Then the culture comes back positive for mycoplasma.

 

Our Story

Our story is similar to both Scenario 2 and 3.  Our first kid to get sick was treated as was the kid in example two.  He was a little buckling that we were keeping intact and were quite impressed with. When he died it was very difficult, both from the standpoint of the loss of the potential as well as watching a creature suffer.  I know now that we didn’t have to lose him or let him suffer.  At the time I was convinced it was “joint-ill” as everything I read seemed to indicate that diagnosis and our vet thought so too.  It was only when a few weeks later that another kid, a little wether, developed the same symptoms that I felt there must be something else was going on.  Even then, I was very doubtful of it being mycoplasma.  We had never had a clinical case of mastitis.  We milk all of our does twice a day, even when they have kids on them part time, so we are quite aware of their udder health.  Everything I read and the vets that I talked to at the time, confirmed these feelings.  Then the test came back positive for mycoplasma.

 At first I felt like quitting the business.  We had THOUGHT our herd was so healthy.  We had THOUGHT we were free of any contagious pathogens.  We did annual CAE and Johnes testing, put tarps up at shows, hadn’t bought any new stock in some time, all of it.  I was humbled.

We decided to have the sample cultured farther to determine out what exact mycoplasma we were dealing with.  This took another few weeks and more funds.  We also took milk samples from all our does and had them cultured for mycoplasma as well.  Although, by this time we knew that the shedding of the microorganism can be intermittent and asymptomatic.  We also knew that there was a possibility that we had spread it to other does via the milking machine.  I felt so dismayed.  I wondered how we could deal with this and still enjoy the farm.

The milk samples all came back negative.  Nice in one way, not in another- at least a positive sample would have told us who our culprit was and given us something to act upon.

The joint fluid sample came back positive for Mycoplasma mycoides mycoides Large Colony (or MmmLC).  This is the one that I had come to suspect after spending the intervening weeks reading everything I could find on mycoplasmas.  It is also the one I hoped for (if you could hope for such a thing) as it seemed to be the least pathogenic of all of them.

Changes.  We had to make them.  We had to for our own assurance as well as for our buyers.  We started pulling kids at birth and feeding heat treated colostrum and pasteurized milk.  For the does in the milking string, we implemented a manual “back-flushing” regimen to sanitize the inflations between animals.  We had more samples of milk taken and cultured after all of the fall fresheners were milking. All samples are negative and none of the other spring kids that received mixed milk have ever sickened.

Our two kids that sickened, received commingled (mixed from the whole herd) raw milk. One of the does had to be an asympotomatic carrier.  She may never shed again, or she might.  Had she passed it to other kids who never sickened, but are now carriers as well?  We were suspicious of one doe whose SCC (somatic cell count) was higher than normal during the time the kids would have received her milk.  Her tests all come back negative, but we placed her in a pet home anyway.  We are now (at the time of writing) over three years out from our experience.  None of the other goats that received the mixed milk at the same time as the ones that were ill, have ever had any problems.  We continue to not allow their kids to nurse and if we feed commingled milk, it is always pasteurized.

Mycoplasma Arthritis- How it Happens

When a kid receives milk with the MmmLC in it, the mycoplasma most often attacks the joints first.  When this happens the kid’s temperature spikes (a spike means a sudden increase followed by a rapid decrease). The front knee joints are often the first to be effected, with firm swelling and seem painful to him when touched.  Their gait becomes tentative and stiff.  Very rapidly they become septic (a body-wide infection) and their temperature begins to drop (this is why you do not see extremely high temperatures with mycoplasma, it attacks so rapidly that their systems begin failing before their body can attack it with extended fever).  For the less observant herdkeeper, the kid can even look as though it has enterotoxemia- with its hunched posture and painful cries.

For all animals with mycoplasma in their system, including the asymptomatic ones, stress can cause an active, symptomatic case.  An unstressed animal can remain asymptomatic and healthy, but still shed the pathogen.

For our two kids, one developed it after a long transport (when you would also suspect “shipping fever” and might treat for that instead) and the other sickened just shortly after castration.  All others though, (seven kids in addition to these two) that received the same milk at the same time, and have never showed signs.  But we will suspect them as carriers and not ever feed their raw milk to their kids.

Other Stories

In doing the research for this article, I called upon other breeders who had experienced mycoplasma in their herds.  I received several private communications from breeders who have had proven cases of mycoplasma.

In all of the stories there was a common theme of unpredictability. For example, one doe had two kids with only one that sickened and died.  The other kid never showed symptoms and never passed it on to her kids, nor did that dam ever have any kids sicken from it.  In another small herd, one doe spiked a high SCC (somatic cell count) then died a few months later. Her necropsy cultures were positive for mycoplasma.  She apparently never passed it on to her adult herd-mates or to her kids. These breeders felt strongly that mycoplasma is very opportunistic..  It may be out there in many herds, but only strike the occasional animal that become stressed or are immune suppressed for some reason.

All of the breeders who kindly shared their experiences with me asked that they remain anonymous.  Due to the past virulence of the disease and the stigma associated with mycoplasma positive animals, they are hesitant to openly share their experiences. Understandably so.

Conclusion

We live in a world where disease can spread rapidly and cause great financial loss to farmers and breeders.  This fear of both the disease and the potential financial loss can lead to the lack of open information and therefore education for breeders.  By sharing our experience openly I knew that we might lose sales.  But I feel strongly that sharing information will lead to a healthier population of animals and a more informed buyer or breeder.

Given the fact that we had a “closed herd” that appeared vigorous and healthy yet one of the animals was a carrier, you can draw the conclusion that there must be many undocumented carriers of mycoplasma. Therefore, learning to identify the symptoms, prevent further spread, and gain knowledge of the organism is critical.  Even if it is never eliminated, suffering can be alleviated and losses cut if we know what we are dealing with.

Once you come to terms with the likelihood that many herds could have undetected mycoplasma carriers; that these carriers might never spread the disease; that if spread the disease is not the death sentence; and that you can implement a highly effective preventative program if you choose, then the fear changes to knowledge and power.  We owe it to our animals and to our fellow human-herdmates to share our experience.

End.

Updates and Q&A

Q: Can the joint swelling be in only one knee?

A: Yes, recently veterinarians have diagnosed some cases of joint arthritis from mycoplasma in only one knee (front leg) or joint,of an animal. These cases were accompanied by the same symptoms of initial high fever, general malaise (not feeling good, no appetite, depressed attitude, etc), and death if not treated.

Q: I bought a doe whose adult daughter had kids who came down with mycoplasma. Should I assume the doe I bought (the mother of the dam whose kids got mycoplasma) is a carrier?

A: While you can’t know for certain, I think it would be wise to assume she is and consider not allowing her to raise her own babies. They should not nurse from her or be fed any un-heat treated colostrum or unpasteurized milk.

Q: Can a buck infect a doe through his semen?

A: To my knowledge passing of MmmLC (the type that seems to be the most common here in the US and the only type I have any experience with) is primarily passed through the milk of a carrier doe who is shedding the microorganism. In theory it can be passed other ways, but that seems to be quite rare. We still have a doe that was symptomatic as a kid (the full sister of the little buck that died here in 2005 from the disease). She has never been allowed to nurse her kids and we continue to pasteurize all milk fed to kids that is not from their mom’s only, but she is not segregated from the herd in any way. We have not had any cases since 2005.

Q: I suddenly had three cases of mycoplasma in kids this spring, but I have had all of the mom’s for many years, how is that possible?

A: It is entirely possible for a doe to not shed the microorganism until something causes extra stress, and then the babies have to be nursing her (or you feed the milk to them raw) at the same time.  This is why it is so difficult to be able to say that it is not present in your herd. For all we know, we all have a carrier or two, and they may never shed it, or the kids could become carriers but not have any symptoms.

Q: Our vet told us to give the kids (from a doe that we worry might be a carrier, although she has never had any symptoms) a shot of LA 200 (oxytetracycline) to make sure that they don’t get mycoplasma, does that make sense?

A: I am never in favor of giving antibiotics without any diagnosis, especially just one treatment. You are in essence exposing every microbe in the animal’s body to an ineffective dose that will only cause the ones that you want to kill (someday) to grow a bit more resistant. If the kid does have mycoplasma, one treatment won’t kill it off, and even if the kid has an active case and you treat them with a full course, you are not going to get rid of all of the microorganisms, they will still be a carrier. So it makes more sense to be observant and watch these kids for symptoms and then treat them properly.  Also, don’t forget to feed probiotics when giving any antibiotics.

Q: Speaking of probiotics, won’t giving those at the same time as antibiotics kill the antibiotic?

A: No, probiotics do not kill off antibiotics, they simply help replace some of the good bacteria in the animals digestive tract that the antibiotic will be killing.

Q: What is your best advice if I am worried about having mycoplasma in my herd?

A: First, be observant for the symptoms. Second, only feed the raw milk and colostrum of any mother to her own kids (that is assuming she is free of other diseases transmitted via milk). Last, if you feed milk from more than one mom to a group of kids, always pasteurize it.  I think I am hearing so much more about mycoplasm because, as people’s herds become free of CAE, they are beginning to feed raw milk to kids again. I think this is just proof that mycoplasma has never gone away and never will.

Gianaclis

 

Living Simple Ain’t Easy

We live a life that many would consider to be blissfully simple. Our electricity is generated by solar panels and a small micro-hydro power turbine run by our seasonal stream, Brown’s Gulch. We homeschooled our kids and live in a tiny cabin, augmented by a large, communal type space above our dairy barn. I don’t get manicures or pedicures or even polish my nails (who wants polish bits getting into the artisan goat cheese we make?). I rarely style my hair and don’t mind shopping at The Goodwill. We have wood heat, no air conditioning, cook meals from scratch, and raise chickens for meat- I, the strict vegetarian, do the slaughtering and butchering of this kindly-raised, healthy protein source for my meat-eating family.

This morning just about the worst thing that could happen to an off-the grid system occured. We had a total blackout. Bizarrely, it occurred at the precise time, 5:15 AM that our alarm clock is set to ring, or in our case a background white noise is turned off. So the silence is what usually wakes us up. But this time not only the sound ceased, but also the glow from the digital display went dark and the fan bringing cooling air in the window spun to a halt. It took about eight seconds to realize that something was seriously amiss.

We live in a part of the country where it is common for rural power customers, the on-grid people, to have periodic power outages during inclement weather. An ice laden tree branch takes down a power line or a heavy wind pushes lines together, blowing a transformer. While we have done our best to not feel a little smug when the rest of the community can’t flush their toilets or use their cordless phones while we are blithely flipping on light switches and posting to Facebook , I will confess to the tiniest hints, just the tiniest, of smugness.

Well, when you live off-grid, the power only works when you properly maintain and monitor your power “plant”. After five years of vigilance, it only took two days of letting our guard down to do possible irreparable damage to a battery bank that would cost around 10 grand to replace.  Our oversights were a combination of leaving the diversion load on (it is meant to shunt surplus power to our hot water holding tank), not having the generator in the emergency start mode (when it is supposed to automatically start if the battery bank drops to critical levels), and topping it off with a dead generator battery (so it wouldn’t have started even if it had been in the emergency mode).

So now, with the generator running and the sun shining on the 36 photovoltaic panels, we wait; Vern researching the likelihood of reviving the batteries and both of us figuratively crossing our fingers that the worst thing that could happen will soon become just a lesson in complacency.

 

 

A Farm is Not a Peaceful Place

One of those rare peaceful moments, seeing the moon setting behind the mountains to the west of our farm

A Farm is Not a Peaceful Place

There are times when our life is peaceful. But they are rare. Everyone wants something, or has something to share. The goats want to go for their walk or a hen has just laid an egg. The guardian dog sees a deer or the wild turkey has heard an echo. Our daughter has a question, our intern has a question, someone on the phone has a question, or a stack of emails are yelling in my head with their unanswered questions.

If you get up early enough in the morning, it might be peaceful. You can listen to the sounds of the night and see the silhouette of the mountains in the east. But as soon as you open the barn doors, the animals are aware of your presence and their expectations become your priority.

There are moments when everyone is satisfied, and you can hear yourself think. But it doesn’t last. Even at night, the noise, the fears, the possible suffering- that you are responsible for preventing- creeps in and startles you awake. It might be a dream now, but it could be a reality at any moment.

So many things, so many people, need you. You can’t complain about your boss, you are them. You feel responsible for the life that you have- by association- dragged your loved ones down into.

Everyone thinks you are living “the life”. They philosophize and compare. They don’t understand. They have jobs they can walk away from. They have weekends. They might even have health care and retirement plans. Our retirement plan is to be able to stop before regret dominates.

The farm is noisy, the farm is demanding, the farm is our life, our life is not our own. We love the farm, we hate the farm. We are the farm.

I Don’t Wanna Be a Rock Star!

No “Rock Stars”, Please!

Gianaclis Caldwell

I have an issue with the current reverence that the term “rock star” is supposed to infer. I know, people are just trying to show their admiration, respect, whatever, but really, “rock star”?

Our cheese has been called a rock star. We, as cheesemakers, here at Pholia Farm have been called rock stars. (And this has all been in recently published books, by the way) And I have been called that by some lovely, well-meaning people as a way of introduction to others.

Let me confess that my own ego is not immune to the attention that such a term brings, but then isn’t that part of the problem?  Ego is great, when kept in a proper captivity, but let it loose on the stage of life, with adoring fans feeding the beast with accolades and applause, and it quickly becomes a monster. A monster that for some reason our culture insists upon worshipping.

And I am nothing! Imagine the difficulty of fighting off this beast when you actually really accomplish something- or are truly gifted.  Thank goodness that hasn’t happened!

I don’t believe our species, our culture, or our world needs any more rock stars, real or perceived. If we could only learn to idolize the true leaders, heroes, and quiet pillars of life, wouldn’t that be something?

Oh, anyone seen Steven Tyler’s new music video…?

The Legend of Goat Milk as “The Most Complete Food Known”

The Urban (Rural?) Legend of Goat Milk “The Most Complete Food Known”

Gianaclis Caldwell

Okay, just Google it. “Goat milk complete food”. You will find the venerable Journal of American Medicine (JAMA) quoted repeatedly (I counted 14 different citations on the first two pages of searching) in such turns of phrase as “as the Journal of American Medicine states, goat milk is the most complete food known” or “according to the Journal of American Medicine, goat milk is the most complete food known”. Hey, maybe you even have this quote on your website or in your brochures, if you are a goat milk producer and fan like I am.

Even a recent issue of a beloved dairy goat magazine devoted an entire article to the topic (reprinted from a natural news type website) and citing the JAMA with the same quote.  While I am all for promoting goat milk as a fabulous food, I instantly become skeptical when hearing a prestigious source quoted without also being properly attributed.

So I went to the JAMA website and did a search of their article archive. The only reference I found was a letter to the editor in Volume 120, # 4 published in September of 1942 that asked if the following quote (which the reader read in another publication) were true: “The Journal of American Medical Society states that goat milk is the purest, most healthful, and most complete food known.” The editor responds that no such statement could be found in the JAMA. That was over 50 years ago, people.  If anyone has found an attributable JAMA source for this quote, then please share it and set me straight!

Is there really such a thing as a “complete food”? If you Google that term, you will come up with a lot of claims that bee pollen and hemp seed are the most complete foods known. (Not surprisingly, the JAMA is quiet on the subject)  Even if true, just think how many bees would have to work overtime to provide enough pollen to sustain one 150 pound person or the number of hemp plants you would have to grow (although some people might think that would be just groovy)  What I am trying to say is that this obsession with the “perfect, most complete food” is kind of silly.  We are meant to eat a variety of foods- the fresher and less processed the better. The focus should be on “the most complete diet known to man”.

If you are interested in comparing (a bit more objectively, perhaps) cow, goat and human milk, then I recommend going to http://drinc.ucdavis.edu/goat1.htm  and reading “Dairy Goat Milk Composition”.  After reading it, you will likely conclude that most milk types offer a lot of nutrition, but none are perfect. And don’t forget that HOW milk is processed and treated after it is removed from the mother (be she cow, doe, ewe, or woman) has a huge effect on the retention of vitamins and minerals, the loss of enzymes, and the alteration of proteins and fats. There is a saying that I love to repeat (but I don’t know the source) that “milk was never meant to see the light of day”. In other words, milk is at its best when going straight from teat to tummy. (That is my quote and you can use it if you like)

So get out to the barn; milk your goats (who I think are the most completely wonderful animals known); drink their delicious milk; appreciate the gift that they, as beasts, and their milk are; and then double check your quotes and what you repeat.  And after all, since when do we really need the American Medical Association and their Journal to validate our own good taste?

July 10, 2011

Keeping your Home Milk Supply Clean

Here is another article I wrote about a year ago.  I did a little study using several local volunteer farms who promised to not change anything about their milking techniques and allowed me to take samples of their milk, which I then sent to a certified laboratory for testing.

How Clean is Your Home Milk Supply-Really?

By Gianaclis Caldwell

First Printed in United Caprine News, September 2010

Like most people who have a few dairy goats you probably believe the milk you drink and feed to your family (and maybe even sell) is clean and safe.  But you might want to think again.

We run a small, licensed cheese dairy inOregon.  We too thought our Grade A milk produced in our inspected, licensed facility was as pure as it could be.  After all, the state conducts routine tests on our milk to verify its safety, but when we first got started I didn’t know how to correctly read the results from these tests. I assumed that if the numbers were less than stellar, that someone would tell me, but in reality, only when the bacteria counts reach the official violation level is the dairy owner usually informed.

Without our noticing, the bacteria counts began a slow and steady climb that suddenly shot sky high.  While the milk was still technically safe to use for cheese, it was far below the standards that are ideal.  This was a pivotal moment for us.  It did three things: It caused me to study and learn how to read and interpret milk lab tests, inspired me to pay close attention to the lab results when they arrived, and completely changed our approach to sanitation in our milk processing areas.

After experiencing this from the standpoint of a licensed producer that believes in the right to drink raw milk, I started thinking about the home producer and their milk quality.  If a licensed dairy performing rigorous cleaning rituals could find their milk not clean, what about the home producer?  Here inOregon, raw milk can be sold legally direct from the farm, as long as only a specific herd size is not exceeded and other criteria are met.  So not only could the home producer be serving tainted milk to their families, but they could be selling it to any number of people for whom bacterial contamination might cause health concerns.  Even beyond the health issues, there is the flavor concern.  A common cause of poor flavor in milk (especially goat milk) is the breakdown of fats by bacterial enzymes. So, for quality milk from all standpoints, cleanliness is paramount.

 

The Study

 

I decided to recruit some volunteer farms that would allow me to collect samples of their milk to send to a lab for testing, as well as fill out a questionnaire about their milk sanitation practices. Each producer promised to keep their cleaning and collecting routine the same.  The results of the lab tests were amazing; from milk that was extremely clean, to one that was over the usual violation level. The good news was that even the “dirtiest milk” did not have high levels of the most common pathogenic (illness causing) bacteria e.coli. (The samples were not tested for another bad bug, listeria)

I collected two milk samples from five farms.  One sample was fresh, one just a few days old. Two of the farms hand milked and three used milking machines.  The samples were packed on ice and overnight shipped to Agrimark Central Laboratory inMassachusetts. (I chose Agrimark for their easy to read and order “raw milk profile”)  Before we go into the results, lets go over a little background on just what kind of tests can be done on milk and what these tests can tell you.

 

Milk Quality Tests

 

Everyone who milks their goats, cows, or sheep should know a little bit about milk quality tests.  The first thing you should know is that anyone can have their milk tested.  It is not expensive (the tests run in this study cost about 20.00 for each sample) and can be very helpful in you quest for producing good, safe food for your family and neighbors.

The first, and most common, test done on milk is the raw standard plate count (SPC) (some times called simply “raw count”). The SPC counts the TOTAL amount (measured in colony forming units) of bacteria in the milk.  Both good and bad.  It is a starting point for looking at the milk quality.  For example, if the SPC is extremely low, you can bet that the bad bacteria count is also low.  But if the SPC is high, it doesn’t necessarily mean that the milk is “bad”.  If you are a cheesemaker, then you know that by adding culture, you are adding bacteria to your milk.  Sometimes the home milk supply is “pre-cultured” with some pretty good bacteria from your animals.

The next test is the pasteurized count.  For this test, the milk is pasteurized and then the bacteria units are counted.  Remember, normally pasteurized milk (in other words NOT ultra-pasteurized) is not sterile, a certain number of bacteria do survive.  These are the heat loving bacteria (thermophiles).  For most of us who are drinking and using our milk raw, the pasteurized count is of little significance.

The test that I find most interesting is the preliminary incubation count (PI or PIC).  For the PI, milk is held at 50 degrees F for a period of time and then the bacteria colonies are counted.  Bacteria that like the cold (psychrohiles) will grow well under these conditions.  They are of great importance for issues regarding milk flavor when the milk is stored for periods of time.  Once the milk is chilled, the cold loving bacteria will continue to grow (very slowly if the milk is about 38 degrees F).  Some bad bacteria are psychrophiles too, such as listeria (a potentially deadly pathogen).  So knowing what your milk’s PI is after it has been stored for a while, can be very useful information.

Then there are specific tests for certain bad bacteria such as e. coli, staph aureus, and listeria.  First a count is done for the total number of coliforms (of which e. coli is the worst).  If that number is low, then the e.coli number will be of little value, but if it is high, then it is important to know just how much of those coliform colonies are e. coli.

Staph. aureus is a very common cause of clinical and subclinical mastitits in lactation animals.  It is also of increasing concern for human health.

 

The Study Results

First lets take a look at the lab results as a chart as well as the acceptable ranges, then I’ll break it down to analyze each farm and their procedures, test results, and some possible remedies where needed. Remember, I took a sample of milk that was 5 days old when tested (numbered “1”) and a sample that was 2 days old when tested (numbered “2”).  Then I will go over the suggested cleaning regimen for milking equipment.  But, as you will see from the volunteer farms, many of them perform cleaning procedures that vary greatly from those suggested and are evidently working quite well! ( If you are unsure of how to determine measurements of products and proper use, contact the supplier, they should be able to help you.)

 

Bacterial Testing Results

 

Farm Sample

SPC Raw

Past. Count

PI

Total Coli

E. coli

Staph

A1

2,000

20

83,000

<1

<1

<10

A2

5,000

20

2,000

<1

<1

900

B1

780,000

<10

>600,000

<1

<1

<10

B2

13,000

<10

98,000

112

<1

<10

C1

<1000

10

6000

<1

<1

<10

C2

7,000

10

1000

<1

<1

1200

D2

1000

10

1000

<1

<1

<10

E1

30,000

<10

>600,000

200

<1

<10

E2

9,000

<10

150,000

1

<1

<10

 

Milk Test Result Ranges (From Dairy Practices Council)

 

Test

Ideal

Acceptable

Common Industry*

Regulatory Limit

Raw Count

<1,000/ml

<5,000/ml

<10,000/ml

100,000/producer

300,000/commingled tanker

Pasteurized

Count

<250-300/ml

20,000/ml (pasteurized milk)

PIC (should be <3-4x SPC)

<25,000/ml

25,000-50,000

No legal limit

Coliform

<10/ml

<50-100/ml

<10/ml (pasteurized milk)

 

*Related to premium payments within industry

 Farm A

This farm’s milk was pretty clean. They hand milk into a hooded pail in a fairly typical setting- milk stand is in the barn with the animals. Teats are not dipped after milking (note, the farm with the cleanest milk in the study did not post dip either). The milk is chilled by placing in a refrigerator next to the vent from the freezer compartment.  They were unsure of how long it took for the milk to cool completely.

If you will notice, their raw counts are not too bad, but the PI is quite high on the older milk sample.  This indicates that there has been a significant growth of cold loving bacteria while the milk was stored, usually indicating that the milk did not reach ideal storage temperatures rapidly enough, or that it warmed up a bit during storage.  Interestingly, the fresher sample had a higher bacteria count and the staph count was elevated, but the PI was low.  The fresh sample was warm when I collected it from the farm.  I cooled it rapidly in my collection ice, this probably led to the much reduced PI count.

Suggestions: Cool the milk more rapidly and check the milking does for subclinical mastitis with an on-farm somatic cell (SCC) test such as the California Mastitis Test (CMT).

 

Farm B

This farm’s milking procedure, according to their questionnaire, sounds pretty thorough- so it was initially baffling to see the very high bacteria counts.  Farm B uses a milking machine, washes the udders with hot water and a wash cloth, pre-strips, post dips, cools the milk in a refrigerator, and cleans the milking equipment with chemicals and cleaners designed for the job.

The older milk sample has a raw count far beyond the violation level and an extremely high PI. The fresher sample has a much lower raw count, but still has an out of proportionally high PI.  It also has a coliform count 10 times the ideal.  So what could the problem be?

Suggestions: The first place troubleshooting should be checking the milking equipment for cleanliness. Using a magnifying glass and strong flashlight, each component should be disassembled and inspected. A common area for buildup is in the typical goat claw used on many milking machines. In addition rubber gaskets and hoses might need replacing.  Remember, microscopic nicks and grooves can easily harbor colonies of bacteria that your fresh milk will wash over during each milking- providing food for these colonies and contamination for your milk. After addressing these issues, a ramped up cleaning should be preformed using double the amount of detergent, utilizing 140 degree water (140 degrees at the start of cleaning will ensure it is still hot enough at the end of the cycle), and performed for 10-15 minutes (or until the water drops below 120 degrees).  This should be followed with a 5 minute acid wash. After this “super cleaning”, they will want to ensure that their water is the right temperature (usually 120-140 degrees) during daily cleaning.  When wash water drops below the ideal, it re-deposits proteins and fats on the equipment. The other factor that can limit the effectiveness of cleaning is the pH and hardness of the water source.  Farm B also does not pre-sanitize their milking hoses, this step should be considered as well.  The last thing that Farm B should do is chill the milk more rapidly, this will help prevent that elevated PI.

 

Farm C

This farm hand milks into open pails, does not post dip teats, cleans the milking equipment in an automatic dishwasher and routinely uses an acid wash.  They milk two goats and then filter that milk and begin its cooling before proceeding with the next goats, this is probably contributing to their lower PI counts.

The older sample has a remarkable low raw count and an acceptable PI, the newer sample has a bit higher raw count and an elevated staph count (probably leading to the higher raw count).

About the only suggestion I have for this farm is routinely checking does with a somatic cell detecting test such as the California Mastitis Test (CMT), as staph is often present in mastitic milk, even in subclinical cases (where no clumping, stringing, or udder heat is present).  Good job!

 

Farm D

This farm uses a milking machine, uses single use wash clothes for cleaning udders, and does not post dip teats.  The milk is chilled within 10 minutes of milking by filtering into a container which is then set into an ice water filled pail. They use antibacterial dish soap to manually clean their milking hoses and equipment.

While I spilled the fresher of the two milk samples when preparing them for shipping, Farm D’s older milk sample is amazingly clean.  This farm claimed that their milk would maintain its flavor for up to two weeks, and I believe it!

Suggestions: Keep doing what you are doing!  Bravo!

 

Farm E

This farm uses a milking machine, cleans udders with a quaternary udder wash, and post dips teats. The milk is filtered into a clean container within 30 minutes of beginning to milk and placed in a refrigerator. The milking equipment is cleaned by pumping rinse, wash, and acid rinse solutions through the hoses.  155-180 degree water (although water temperature does not need to be higher than 140, especially when low temp detergent is used) is used with lo-temp automatic dishwashing detergent with chlorine added.

Both samples have raw counts above the acceptable level and PI counts out of proportion to the raw count (remember, the PI is typically 3-4x as high as the raw count). Total coliforms on the older sample are quite high as well.

Suggestions: The cleaning procedure sounds good on first examination, but obviously something is missing. One thing to remember is that each cleaning step has an ideal amount of chemical, temperature of water, and length of time. Any gap in these steps can lead to problems. It is possible that the length of cleaning time is inadequate, the amount of detergent is not sufficient, or even the water type is negatively effecting the performance of the chemicals.  As with Farm B, the equipment should be disassembled and thoroughly inspected and a super cleaning should be performed.  The milk chilling time and temperature goals should also be improved, rarely is chilling by setting the container in a refrigerator sufficient.

 

Proper Daily Cleaning of Milking Equipment

 

Step

Do

Common Errors

Pre-Rinse

Rinse all equipment with 100-110 degree water. Too hot of water causing proteins to bind to surfaces or too cold causing fats to form a greasy film.

Wash

Use a chlorinated alkaline detergent mixed in the right amount for your water type (hard or soft and pH) in water that is 120-140 degrees F.

For hand washing, soak all parts in this solution for five minutes and then clean with brushes.

If pumping through the lines, clean for 5-10 minutes, making sure water does not cool below 120 degrees.

Drain wash water.

Water too cold or cooled to below 120 by end of cleaning, causing the re-depositing of fats and proteins.

Not cleaning for long enough.

Not disassembling and manually cleaning parts not cleaned well by pumping or brushes.

Acid Rinse

Mix acid rinse in lukewarm or cool water in amount directed. Soak or circulate solution for 2-3 minutes.

Drain and hang equipment to air dry.

Not using an acid rinse at the proper pH can leave a residue of the alkaline detergent, allow buildup of minerals, and leave the equipment more vulnerable to bacterial contamination between uses.

Pre-sanitize

Just before use, sanitize all equipment with a chlorine or other type sanitizer mixed as directed in cool water for 30 sec min.

Drain well.

Too strong of a solution will pit and erode stainless steel and leave a residue on hoses. Too weak will be ineffective.

Putting it all Together

As they say, milk was never meant to see the light of day- it was meant to go directly from the mother into the mouth of her offspring.  Once we interrupt that cycle and attempt to collect and keep a product that was never intended to be handled in that fashion, we increase the odds of reducing its quality and safety.

While using a milking machine is often thought of as the cleanest method available for collecting milk, this only holds true when a very strict regimen of cleaning is adhered to.  Milking hoses and paraphernalia have many nooks and crannies which make thorough cleaning a challenge. Other than cleaning of equipment, proper chilling of the milk seems to be the most common area that needs improving.  I think once the milk is in our refrigerators, we kind of let our guards down, it seems safe in there! But if you try to picture the milk as a growth medium, for not only your family, but for the hoards of bacteria, both good and bad, that are on the animals, in the air, and possibly on our equipment, then you more likely establish procedures for ensuring the safest and tastiest home milk supply possible.

GC’s Ten Tips for Collecting Clean Milk and Keeping it Clean

  1. Give your doe a dairy clip- clip hair from udder, belly, legs and around her tail for the latest in trendy, dairy fashion!
  2. Milk with dry, clean hands- never wet!- or even better, use a pair of disposable gloves while milking. They say that dirty gloves are probably cleaner than clean hands!
  3. Milk in to a hooded pail or place your stainless strainer (with a fresh, clean, single use filter in it) on top of the pail during milking!
  4. Make sure your milk jars are clean and sanitized before adding warm milk. Remember, any bacterial residue in the container will love the warm milk!
  5. Keep it on ice- right after milking, set the filtered milk into a pail of ice water and stir.  If you can get the temperature to 40 degrees within 2 hours of milking, you are chilling perfectly.
  6. Clean up immediately! Never put off cleaning your milking equipment.
  7. Use cleaning detergents and sanitizing chemical in exacting amounts and with the right temperature water.
  8. Let equipment dry between use- bacteria need moisture to surviv- a wet surface is likely a contaminated surface!
  9. Don’t forget to replace any rubber, plastic, or silicone parts of your set-up as recommended!
  10. And last, use your milk within a week, it might still taste good, but any cold loving bacteria will be developing a population by then.

 

Cheese Mites- A Creepy Little Secret

Here is an article I wrote awhile back on the fun little problem that comes with aging naturally rinded cheeses:

How the “Mitey” Have Fallen- Adventures with Cheese Mites

By Gianaclis Caldwell

May 2010

Cheese lovers beware, there is another very determined turophile (cheese devotee) on a mission to devour the same fine, long aged cheeses that you too love to eat. These little pests can consume a significant portion of aged, naturally rinded cheeses and in the process take a bite out of the slim profit margin of the artisan cheesemaker.  While cheese mites are a desired part of the aging of a handful of European cheeses, for most cheesemakers they can be a costly nuisance.

I remember when cheese mites first arrived in our aging room.  For many months I innocently thought the brownish powder accumulating on the aging room floor between cleanings, of course, was “cheese dust”- some sort of naturally occurring shedding of the paprika and oil rubbed rinds of our cheeses.  This naiveté served me well until I visited a fellow cheesemaker who was brushing the same dust off of her cheeses and complaining about mites.  Did I have cheese mites? She asked.  No, I didn’t think so, I replied while at the same time the realization started dawning that I did indeed have my own little infestation going on back home in the cellar.  Upon returning to our farm and creamery I put a bit of said dust on a microscope slide, placed it under the lens, took a look and was disgusted to see the little creeps waving back at me.

It seems that there are mites for every occasion and morsel- cheese mites, flour mites, mold mites, dust mites, and so on, and many of them are not too picky to also eat out of their specialty. It is through this versatility that mites find their way to the aging cellar. Since most of us do a little baking or know someone who does, we become the unknowing host to some little hitchhikers.  Mites are known to attach themselves to hair, clothing, and even flies in their quest for the good life.   I talked to one cheesemonger who said she and her staff would hold “cheese mite races” if they were bored.  Now, remember these are not speedy creatures, so I am not sure exactly how much excitement a mite race could generate, but it does sound creative and somewhat job related…

Let’s talk about that “cheese dust” a bit more.  What the heck is it?  Well, for those of you who have seen electron microscope images of dust mites that live in all of our beds (yes, everyone’s) and the little creatures that live at the base of our eyelashes, you can picture what this cheese dust looks like up close- eight legged mites, living and dead, and their excrement (it’s true, “Everyone Poops”).   The good news is that cheese/mite dust doesn’t pose a health risk to us full sized cheese lovers and makers.  There are cases where dermatitis (itchy skin) is a problem for some people exposed to cheese, flour, and mold mites, but usually there are no ill effects (unless you have a weak stomach and make the mistake of looking at them under a microscope right before dinner…)

So what does the cheese mite do to its prey? They dig in and start eating the rind of unwaxed and otherwise unprotected aging cheeses, including bandage wrapped cheddars.  Generally they don’t start to work on cheese under a couple of months of age, (they seem to have a connoisseur’s taste, but actually the longer aged cheese has a greater degree of protein breakdown- proteolysis- making it a better source of nutrition for the mite),  but it varies depending upon the rind treatment.  For example, cheeses that are being brine washed or rubbed with oil usually don’t see any mite presence until much later in their aging or, if rind treatment continues throughout aging, their activity is limited (the small size of the mite makes it difficult for them to maneuver through sticky, oily, or wet surfaces).  As the mites dine, they create little pinholes (see photo) that later turn into growing craters.  They eat their way under the rind and eventually cause large pits, and what I think of as cheese sink holes.  Initially the damage they do has no effect upon the taste of the cheese, but given time they impart a floral, sweet, rather sickly (to my taste buds) flavor.

So why would anyone want mites on their cheese?  Two fairly well known European cheeses, the German MIlbenkäse (literally mite cheese) and the French Mimolette are probably the two best known examples of cheeses using, what I like to call, mite-assisted-affinage. MIlbenkäse manufacture utilizes mites in an interesting fashion; when the wheels, logs, or other shaped cheeses are ready, they are placed in a box (mites prefer the dark) with mite dust and rye flour.  Evidently the flour provides an additional food source for the mites so that they will still have an effect on the flavor of the cheese, but consume less of the finished product.  Mimolette wheels (whose shape and make is similar to Dutch Edam) are also inoculated with mite dust and then brushed throughout the rest of their aging, to somewhat slow the destruction of the rind while the flavor can be changed by the mite’s activity.

If you are an artisan cheesemaker with a mite “problem” it can be utilized to produce a unique product, but it is important to remember that most retailers will not appreciate a heavily infested cheese being introduced to their cheese case or aging rooms.  In addition, health departments may not recognize mites as an acceptable “ingredient” in cheese.  So what can you do?  There are several options for limiting the damage and level of involvement of these little guys in your aging room.

One of the key factors in limiting mite damage is early intervention.  Once the mites work their way under the surface of the cheese they gain a measure of protection from any attempts to disrupt them. If your cheese isn’t intended to age for more than a few months, this may not be an issue.  Mechanical means of limiting mites included brushing and vacuuming (yup, now your housework extends to the aging cellar).  If brushing, it is best to remove the cheeses from the aging room and brush then onto a damp floor or into a sink, so that the dust is better contained.  Vacuuming can be done with a small vacuum that you keep just for this purpose.  Remember, the running motor will generate heat, which could be a factor for your cooling system.  Both vacuuming and brushing will need to be done very regularly to have much effect, and again, remember that if the mites have already gone “underground” on your rind, these methods will do little good.

Mites also seem to prefer a flat surface and dark, so you will see more activity on the underneath side of a wheel that is aged on its flat surfaces.  Wheels that are aged on their curved sides seem to suffer a bit less damage, as do those not aged on wood.  (It isn’t the wood that is the problem, it is just that the wood helps keep the mites dark and protected- they can’t fall off the wheel as easily!)  When we had some large losses due to mites, we were aging on wood.  Until that time the damage was always minimal.  I tried vacuuming while aging on the wood, but it was difficult to effectively get all of the mite dust off of the wood without moving every cheese on the shelves, and, as I mentioned before, the vacuum generated quite a bit of heat in our small aging room.  We are powered solely by solar power and any additional energy loads can be a concern.

Some data say that mites will not live at refrigeration temperature, so I tried chilling cheeses for a period of days before shipping.  About all that did was slow the mites down.  Some research says that mites can be controlled with temperatures less than 37.4 F (3 C), but that wasn’t my experience with cheese already infested.  And of course, most artisan cheeses would not be aged at refrigeration temperatures, other than perhaps blue cheese.

Waxing, clear coating (sometimes called cream wax but really a polymer based coating), and vacuum sealing will of course prevent infestation, but bandaging will not.  In fact, it is bandage wrapped cheddars that seem to have the biggest problem.  In the past, aging rooms were fumigated to kill mites, but this, thankfully for the environment, is no longer acceptable or allowed.

Some cheesemakers have noted that mites seem to be more attracted to moldy cheeses.  Evidently molds produce pheromones that attract the mites.  The mites serve the mold’s purpose by helping move spores deeper into the cheese as they burrow their way into the rind.  They also open the rind up for natural spore invasion.  So steps that reduce mold growth , such as brushing and brine washing, will also help deter mite activity.

Many cheesemakers find the best remedy to be the use of food grade diatomaceous earth (DE).  When dusted (use a fine meshed sieve) on the surface of the cheese the DE dehydrates the mites. Again, this technique must be employed early in the aging process before the mites have gone below the rind’s surface.  Be sure to wear a mask when using DE, while not toxic, breathing the fine, abrasive powder is not a good thing for your lungs.

Hydrogen peroxide can be utilized when mixed to 10% as a wash either following vacuuming or before infestation occurs.  I have not tried this method, but somehow it sounds effective yet unappetizing if your rinds are typically consumed by customers.

Ozone machines are being used to limit mite damage in larger aging facilities- and some small ones.  What is an ozone machine?  Well, in a nutshell these machines take oxygen (O₂) from the room, utilize an ultra violet light, and change it to tri-atomic oxygen (O₃). Ozone attacks organic compounds, such as mold, yeast, phage, and bacteria.  It has been used for some time in hospitals and other institutions to purify air and has been shown to sanitize surfaces as well.  So how can this help with a cheese mite problem?  The research is unclear on the exact mechanics, but it seems that the mites don’t appreciate the O₃ environment and as mold growth is also limited by ozone, the cheese surface becomes less appealing.  At Pholia Farm we have a small ozone machine (the EQ Ecobox- about 349.00 on Amazon.com) that we utilize for mildew prevention, air freshening, and general sanitation in the cheese make room, but I would never consider using it in our aging room where I want mold growth and bacterial activity.

So to sum it up, anything you can do to make the surface of your cheese less hospitable for mites will help; brine washing, oiling, brushing to limit mold growth, dusting with diatomaceous earth, vacuuming, and turning frequently.  If all else fails, perhaps there is room in theUSmarket for an new American original, perhaps a cheese called, say“Mitolette”?

“The Use of Ozone as a Disinfectant in Dairy Industry”, Technical bulletin No. 27, January 2003. www.ozone-industries.co.uk  May 5, 2010

“Cheese Mites: They’re Back”, Melnyk, Boinder, Marcone, Scott-Dupree, and Hill, Department of Food Science and Environmental Biology, University of Guelph.   May 1, 2010 (Note, this article is no longer available at the link by which I accessed it)

Identification of Cheese Mite Species Innoculated on MImolette and… http://www.journalofdairyscience.org/article/S0022-0302(10)00364-4/fulltext

“The Art of Farmstead Cheesemaking in the British Isles”, McKnight, Qui’tas,

The Babcock Institute for International Dairy Research and Development, Universityof Wisconsin-Madison, www.dbicusa.org/documents   May 3, 2010