Disease o' the month - JOHNE"S DISEASE
- Thread starter DL
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red
Well-known member
I'm trying to figure that out DL- know you should be able to post the file but not sure how.
Austin or Jason- how do you post a pdf file?
Red
Austin or Jason- how do you post a pdf file?
Red
red
Well-known member
Overview for beef producers who sell breeding stock:
Imagine that your best cow, the female that made you proud in the show ring and in the field, is pregnant with her third calf.She never gained right after her last calf. You figured she just wasn’t getting enough feed, so you gave her extra. She had alittle diarrhea, on and off, but you figured it was from the protein supplement. Now,she has diarrhea all the time, and despite areal healthy appetite you can’t put any weight on her. Your vet came out to have a look, ran some tests, and now is back to talkto you. She says your cow has Johne’s disease (pronounced “yo-knees”, not “johns” or “joanies”). What do you need to knowabout Johne’s disease to make rational decisions about the cow, the calf, and your herd?
What is Johne’s disease?
Johne’s disease is a chronic, incurable infectious disease of cattle caused by the bacteria Mycobacterium avium subspeciesparatuberculosis, sometimes abbreviated MAP. Johne’s disease is difficult to detect and easily spread. There is no approvedtreatment, no cure, and infected animals will eventually die from this disease.
How do cattle become infected with Johne’s disease?
Generally, calves are infected when they are less than sixmonths old, often before 30 days old. There are three major ways they can become infected:
(1) calves can be born withthe infection (in utero infection from infected cow);
(2) theycan ingest the bacteria in colostrum and/or milk from an infected dam; or
(3) they can ingest the bacteria frommanure coated udders, by licking or sucking on manure
contaminated gates or other equipment, or from contaminated feed or water. Ingestion of infected manure is
the major way beef calves become infected.
Who is most susceptible to Johne’s disease?
Calves are very susceptible to Johne’s disease. Young stockcan become infected after ingestion of a small number of bacteria. As cattle age they become less susceptible to the bacteria.
How does feed or water become contaminated?
Feed and water become contaminated through manure from infected cattle. Johne’s disease starts out in the small intestine (ileum). The bacteria grow and thrive; some move from the intestines to other parts of the body and some are excreted in the manure. The bacteria ends up in water sources and fields, and can end up in the feed.
Why is Johne’s disease so difficult to manage?
There are three major reasons why Johne’s disease is so difficult to manage:
(1) Cattle are infected at a very young age, but it is years later, sometimes as many as 10 years later, before the infected animal shows signs of disease.
(2) The bacteria that causes Johne’s disease is very hearty and can survive in the environment for up to one year.
(3) There are no perfect tests for detecting infected animals and interpreting tests results is not straightforward.
What does a cow with Johne’s disease look like?
Many animals with Johne’s disease look and act perfectly normal with no evidence of disease. These animals with subclinical infection may be shedding organisms in their manure. As the disease progresses, there are recognizable outward clinical signs, including severe watery diarrhea and weight loss. The diarrhea does not respond to usual treatments and the weight loss occurs despite normal or increased appetite. Basically, the intestine is so damaged by the disease that it cannot do its job – so nutrients and water are lost in the manure. Along with nutrients and water, the Mycobacterium paratuberculosis are found in the manure.
How does Johne’s disease enter a farm?
Although Johne’s disease is almost always introduced into herds by the purchase of an infected animal, common sense biosecurity practices can help reduce the chance of the disease being introduced through non-animal sources. These include vehicles, shared equipment, obtaining feed with potential manure contamination, and preventing cattle from coming in contact with surface water that runs through adjacent farms.
How to control Johne’s disease on your farm· No quick fix! PREVENTION PAYS!
If your farm is free of Johne’s disease, keep it free of Johne’s disease!
· Prevent introduction of the disease
- Purchase only from Status Level Herds
- Pre purchase exam/tests
- Closed herd
- Isolate/retest additions
If you have Johne’s disease
·Management is the key - Your control program must be tailor-made for your farm
· Get your veterinarian involved
· Test and cull
· Cull offspring of test-positive cows
· Hand rear calves
· Fence off contaminated water supplies
· Avoid overcrowding/muddy conditions, especially at calving
How can producers keep Johne’s disease off their farm?
Since Johne’s disease is almost always introduced into herds by the purchase of an already infected animal, it makes sense not to buy animals with Johne’s disease. But this is where it gets really complicated and difficult for producers and veterinarians. The nature of the disease (early infection with late onset of clinical disease; intermittent shedding of bacteria in manure) and the lack of a test that can reliably identify carrier animals early, make it difficult to detect Johne’s disease especially in young stock. The best way to keep Johne’s disease off your farm is to close the herd. If you must buy, know your sources. Buy your cattle from producers who test for Johne’s, participate in the USDA-Michigan Voluntary Johne’s disease Program, and have achieved a “status level” through testing.
Some producers advertise a cow or a herd that is “Johne’s Disease Certified Free”, what does this mean?
The statement “Johne’s Disease Certified Free” is not an official designation. Ask to see Johne’s test charts. Repeated testing for Johne’s disease decreases the risk that animals in that herd have Johne’s disease, but it does not guarantee them “Johne’s disease-free”.
Why is it necessary to cull a test-positive cow with diarrhea and weight loss?
This cow is infected and shedding bacteria, in huge numbers, throughout your farm, which is a great risk to your other calves. Because of the nature of the disease, Johne’s often follows family lines. The recommendations to beef producers who have Johne’s and are serious about getting rid of it are to cull cows that test positive and to cull the natural offspring of these cows. The offspring are at greatest risk for having subclinical infection.
Can I still show this cow?
Cows with clinical Johne’s disease or fecal positive cows should be culled. It is illegal to transport Johne’s disease-positive cattle across state lines except to slaughter. In many states, Johne’s disease is a reportable disease, and veterinarians are required to report finding it to the state veterinarian. Show rules generally state that animals with infectious disease are not to be shown, and of course it would be against state and federal regulations to take an animal with an infectious disease across state lines.
So now what?
One Johne’s disease test-positive cow on the farm usually is the tip of the iceberg. You need to decide, based on your market, your genetics, and your finances how aggressively you want to pursue the problem. Work closely with your veterinarian to plan and implement a long-term strategy for your operation.
How do calves get Johne’s disease?
· In utero, from infected dam
· Colostrum & milk, from infected dam
· Colostrum & milk, contaminated with bacteria from manure
· Manure-contaminated water (tanks, ponds, wetlands)
· Manure-contaminated feed
· Manure-contaminated gates, etc., that calves love to suck on
Anyone selling replacement females, bred females, orbulls, whether commercial or purebred, should beconcerned about Johne’s disease.
Why should beefproducers care about Johne’s Disease?· Loss of valuable genetics
· Loss of markets
· Protect image
· Prevent spread
· Economic losses (decreased weight & fertility)
· Potential human health implications
Imagine that your best cow, the female that made you proud in the show ring and in the field, is pregnant with her third calf.She never gained right after her last calf. You figured she just wasn’t getting enough feed, so you gave her extra. She had alittle diarrhea, on and off, but you figured it was from the protein supplement. Now,she has diarrhea all the time, and despite areal healthy appetite you can’t put any weight on her. Your vet came out to have a look, ran some tests, and now is back to talkto you. She says your cow has Johne’s disease (pronounced “yo-knees”, not “johns” or “joanies”). What do you need to knowabout Johne’s disease to make rational decisions about the cow, the calf, and your herd?
What is Johne’s disease?
Johne’s disease is a chronic, incurable infectious disease of cattle caused by the bacteria Mycobacterium avium subspeciesparatuberculosis, sometimes abbreviated MAP. Johne’s disease is difficult to detect and easily spread. There is no approvedtreatment, no cure, and infected animals will eventually die from this disease.
How do cattle become infected with Johne’s disease?
Generally, calves are infected when they are less than sixmonths old, often before 30 days old. There are three major ways they can become infected:
(1) calves can be born withthe infection (in utero infection from infected cow);
(2) theycan ingest the bacteria in colostrum and/or milk from an infected dam; or
(3) they can ingest the bacteria frommanure coated udders, by licking or sucking on manure
contaminated gates or other equipment, or from contaminated feed or water. Ingestion of infected manure is
the major way beef calves become infected.
Who is most susceptible to Johne’s disease?
Calves are very susceptible to Johne’s disease. Young stockcan become infected after ingestion of a small number of bacteria. As cattle age they become less susceptible to the bacteria.
How does feed or water become contaminated?
Feed and water become contaminated through manure from infected cattle. Johne’s disease starts out in the small intestine (ileum). The bacteria grow and thrive; some move from the intestines to other parts of the body and some are excreted in the manure. The bacteria ends up in water sources and fields, and can end up in the feed.
Why is Johne’s disease so difficult to manage?
There are three major reasons why Johne’s disease is so difficult to manage:
(1) Cattle are infected at a very young age, but it is years later, sometimes as many as 10 years later, before the infected animal shows signs of disease.
(2) The bacteria that causes Johne’s disease is very hearty and can survive in the environment for up to one year.
(3) There are no perfect tests for detecting infected animals and interpreting tests results is not straightforward.
What does a cow with Johne’s disease look like?
Many animals with Johne’s disease look and act perfectly normal with no evidence of disease. These animals with subclinical infection may be shedding organisms in their manure. As the disease progresses, there are recognizable outward clinical signs, including severe watery diarrhea and weight loss. The diarrhea does not respond to usual treatments and the weight loss occurs despite normal or increased appetite. Basically, the intestine is so damaged by the disease that it cannot do its job – so nutrients and water are lost in the manure. Along with nutrients and water, the Mycobacterium paratuberculosis are found in the manure.
How does Johne’s disease enter a farm?
Although Johne’s disease is almost always introduced into herds by the purchase of an infected animal, common sense biosecurity practices can help reduce the chance of the disease being introduced through non-animal sources. These include vehicles, shared equipment, obtaining feed with potential manure contamination, and preventing cattle from coming in contact with surface water that runs through adjacent farms.
How to control Johne’s disease on your farm· No quick fix! PREVENTION PAYS!
If your farm is free of Johne’s disease, keep it free of Johne’s disease!
· Prevent introduction of the disease
- Purchase only from Status Level Herds
- Pre purchase exam/tests
- Closed herd
- Isolate/retest additions
If you have Johne’s disease
·Management is the key - Your control program must be tailor-made for your farm
· Get your veterinarian involved
· Test and cull
· Cull offspring of test-positive cows
· Hand rear calves
· Fence off contaminated water supplies
· Avoid overcrowding/muddy conditions, especially at calving
How can producers keep Johne’s disease off their farm?
Since Johne’s disease is almost always introduced into herds by the purchase of an already infected animal, it makes sense not to buy animals with Johne’s disease. But this is where it gets really complicated and difficult for producers and veterinarians. The nature of the disease (early infection with late onset of clinical disease; intermittent shedding of bacteria in manure) and the lack of a test that can reliably identify carrier animals early, make it difficult to detect Johne’s disease especially in young stock. The best way to keep Johne’s disease off your farm is to close the herd. If you must buy, know your sources. Buy your cattle from producers who test for Johne’s, participate in the USDA-Michigan Voluntary Johne’s disease Program, and have achieved a “status level” through testing.
Some producers advertise a cow or a herd that is “Johne’s Disease Certified Free”, what does this mean?
The statement “Johne’s Disease Certified Free” is not an official designation. Ask to see Johne’s test charts. Repeated testing for Johne’s disease decreases the risk that animals in that herd have Johne’s disease, but it does not guarantee them “Johne’s disease-free”.
Why is it necessary to cull a test-positive cow with diarrhea and weight loss?
This cow is infected and shedding bacteria, in huge numbers, throughout your farm, which is a great risk to your other calves. Because of the nature of the disease, Johne’s often follows family lines. The recommendations to beef producers who have Johne’s and are serious about getting rid of it are to cull cows that test positive and to cull the natural offspring of these cows. The offspring are at greatest risk for having subclinical infection.
Can I still show this cow?
Cows with clinical Johne’s disease or fecal positive cows should be culled. It is illegal to transport Johne’s disease-positive cattle across state lines except to slaughter. In many states, Johne’s disease is a reportable disease, and veterinarians are required to report finding it to the state veterinarian. Show rules generally state that animals with infectious disease are not to be shown, and of course it would be against state and federal regulations to take an animal with an infectious disease across state lines.
So now what?
One Johne’s disease test-positive cow on the farm usually is the tip of the iceberg. You need to decide, based on your market, your genetics, and your finances how aggressively you want to pursue the problem. Work closely with your veterinarian to plan and implement a long-term strategy for your operation.
How do calves get Johne’s disease?
· In utero, from infected dam
· Colostrum & milk, from infected dam
· Colostrum & milk, contaminated with bacteria from manure
· Manure-contaminated water (tanks, ponds, wetlands)
· Manure-contaminated feed
· Manure-contaminated gates, etc., that calves love to suck on
Anyone selling replacement females, bred females, orbulls, whether commercial or purebred, should beconcerned about Johne’s disease.
Why should beefproducers care about Johne’s Disease?· Loss of valuable genetics
· Loss of markets
· Protect image
· Prevent spread
· Economic losses (decreased weight & fertility)
· Potential human health implications
justintime
Well-known member
DL, you certainly made this first one very hard for us poor amateurs out here. If you had put one of the last pictures on with the first three, we could have made some intelligent guesses, much quicker. Johne's when through my mind as soon as I looked at the first 3 pictures, but I could not see anything in the pictures to indicate that. About the only way you could have made this any harder would have been if you could have added a little cement. OH well. we will certainly know next time and I double dog dare you to try to stump us!!!!!
justintime said:
AH, JIT, I consider you a professional and of course there was some method to my madness....most people don't even think about JD when buying....although every state (don't know about programs in Canada) has a JD control program - few producers are involved (ie compared to the total # all over) - and it is very difficult to buy show cattle from tested herds because most of them don't test, "never had a problem" (but do you test, nope never had a problem) --- I do believe that the tide is changing slowly and people are beginning to realize the havoc JD can cause especially for seedstock producers
There are a fair number of us with less than 100 cows who test annually, but not all that many of the "big guys". I am aware that Barry Jordan tests for JD, Dieters, Nagels and Hoff's did before their dispersal - there are probably others...
I have taken the challenge and have another disease with pictures up my sleeve, but we still have more JD
What are you looking at and which one is normal? Can you guess why there is a problem??
Attachments
justintime
Well-known member
I am assuming that the top picture is the healthy tissue,probably from the small intestine, and I am assuming that the bottom picture is the small intestine that is afflicted with Johne's. I am assuming that simply because of the thickened tissue in the bottom pic. The paratuberulosis that causes Johne's causes lives in the small intestine and sometimes into the large intestine and causes the intestine wall to thicken. As a result the intestine wall cannot take the nutrients from the food as it is digested, and it passes through the animal. The Yonge's affected animal literally starves to death, as the disease intensifies. The bacteria is passed out of the body with the feces, and the feces from infected animal(s) are the main source of the spread of the disease. Manure is extremely running and has a distinct "bad" smell. One almost sure sign of Yonge's is that there will be multiples of bubbles on fresh manure. Am I close to right " oh great exhaulted Teacher"?
justintime said:
You get an A +1 (clapping) (clapping)the bottom one is the small intestine (ileum) from a JD infected cow - it is thickened from granulomas (caused by reaction to the bacteria) and basically it is no longer able to do its job (absorb nutrients). It is sometimes referred to as corregated cardboard because of its appearance. The rusult (end stage) is profuse watery diarrhea - that has as you say a distinct odor and often is bubbly (although bubbly isn't necessary for a diagnosis!). Interestingly most people who say they can smell it have about a 100% accuracy - but the real issue is diagnosing JD well before end stage.
shorthorns r us
Well-known member
- Joined
- Apr 9, 2007
- Messages
- 900
DL - you had telegraphed that one? i strongly suspected that was coming. try opening your pdf file in word then copy and paste into the message. if your version of word won't open a pdf file, i am pretty sure that you can download an addin from the microsoft website.
SRU said:
SRU - I can't open the pdf in word (ancient version) but I can open the pdf in acrobat professional and copy and paste it into word - it looked fine in word but when I pasted it on the planet it was one of those where all the lines were different lengths and it was so annoying I didn't hink anyone would read it! (I sure wouldn't
...I have the pdfs for 1 and 2 posted....should I send them to you??shorthorns r us
Well-known member
- Joined
- Apr 9, 2007
- Messages
- 900
sure. i'll get the others fixed up if i can. send them to [email protected]
red
Well-known member
RED YOU ARE SO GOOD!!Thanks (clapping) (clapping) (clapping)!
The bacteria
The bacteria Johne’s disease is a chronic, incurable, fatal infectious disease of cattle caused by the bacteria
Mycobacterium paratuberculosis, also known as Mycobacterium avium subspecies paratuberculosis. The name of the bacteria that causes Johne’s disease is often abbreviated MAP, although sometimes it is abbreviated M paraTB or Mptb. MAP is a distant relative of the bacteria that cause other human and animal diseases, including
tuberculosis and leprosy. MAP is a very hearty bacteria. Although outside the animal it does not multiply, it can survive in water, manure, or in the environment at low temperatures for almost a year. This is one of the
things that makes Johne’s disease such a complicated problem – manure containing the bacteria that cause Johne’s disease can be left in a pond, and a year later a baby calf can drink out of that pond and ingest enough bacteria to become infected. Years later this calf will develop clinical Johne’s disease. Once ingested by the calf, the bacteria invade the wall of the last part of the small intestine (theileum) where they multiply very slowly in cells called macrophages. The usual job of the macrophage is to kill bacteria. However, MAP have created strategies to avoid being killed by the macrophage. In fact, these bacteria destroy the macrophage and slowly infect other cells in the intestine. Eventually, billions of bacteria are found in the intestines and spill out of the
infected animal in the manure.
Young animals are the most susceptible to infection. Most infections in calves are a result of ingestion of the bacteria in manure – sucking on manure-contaminated teats, licking a gate covered with manure, drinking out of a manure-contaminated pond or puddle. The bacteria can also be found in colostrum and milk of infected cows. Finding MAP in colostrum or milk is more likely if the cow is clinically sick with diarrhea and weight loss, but
cows that are infected and appear healthy can also shed bacteria in their milk. Calves can also become infected by getting the bacteria in utero from their dam. Again, this is more likely if the cow is clinically sick (showing signs of Johne’s disease, diarrhea and weight loss). MAP grow very slowly, both in the cow and in laboratory culture. The slow growth of the bacteria is one reason it takes a long time for the infected cow to show signs of disease. The slow growth also makes it difficult to quickly diagnose the disease by culturing the bacteria in manure
samples. Several things about the MAP bacteria explain the unusual nature of the disease. The fact that the bacteria live inside the cells means that they are hiding from antibodies that animals typically use to fight infectious disease. Since the blood test (ELISA) measures antibodies to the bacteria, and in the early stages of the infection the bacteria are hidden from the antibodies, the ELISA has nothing to measure, so the test results are negative. As the disease progresses, the bacteria multiply outside the cells and antibody production begins. This is why the ELISA is more accurate as Johne’s disease becomes more advanced.
Another complicating factor is that except late in the disease, bacteria are not constantly shed from the intestines in the manure. This means that a negative culture does not mean that the animal does not have Johne’s disease, only that she is not shedding at the time the sample was taken. Since the bacteria is slow growing, it takes a long time for the bacteria to multiply enough to cause disease. This results in a long time from the onset of infection in baby calves to the development of disease in adults, usually in the 3-to-7 year old range. And finally, the slow growth of MAP means it takes a long time to grow it in culture. Diagnosis of
infection by fecal culture can take up to 16 weeks. The ability of MAP to grow inside cells, to survive for a long time outside the animal, and its slow growth in the laboratory are some of the reasons the disease is so difficult to diagnose and manage.
The many faces of Johne’s Disease
Johne’s disease is an equal opportunity infection. Cattle of all breeds are susceptible. Rare breeds and
common breeds can become infected. Beef cattle, dairy cattle, working oxen, miniature cattle, show
heifers, rodeo stock and pet cows can become infected. Every animal on this page was infected with
Mycobacterium avium paratuberculosis, the bacteria that causes Johne’s disease. Every animal on this
page died, was euthanatized, or sent to slaughter because of Johne’s disease.
Beef cattle, dairy cattle, working oxen, miniature cattle, show heifers, rodeo stock
and pet cows can become infected.
Things that will decrease
the ability of MAP to
survive in the environment.
Sunlight
Drying
High (alkaline) pH
The bacteria
The bacteria Johne’s disease is a chronic, incurable, fatal infectious disease of cattle caused by the bacteria
Mycobacterium paratuberculosis, also known as Mycobacterium avium subspecies paratuberculosis. The name of the bacteria that causes Johne’s disease is often abbreviated MAP, although sometimes it is abbreviated M paraTB or Mptb. MAP is a distant relative of the bacteria that cause other human and animal diseases, including
tuberculosis and leprosy. MAP is a very hearty bacteria. Although outside the animal it does not multiply, it can survive in water, manure, or in the environment at low temperatures for almost a year. This is one of the
things that makes Johne’s disease such a complicated problem – manure containing the bacteria that cause Johne’s disease can be left in a pond, and a year later a baby calf can drink out of that pond and ingest enough bacteria to become infected. Years later this calf will develop clinical Johne’s disease. Once ingested by the calf, the bacteria invade the wall of the last part of the small intestine (theileum) where they multiply very slowly in cells called macrophages. The usual job of the macrophage is to kill bacteria. However, MAP have created strategies to avoid being killed by the macrophage. In fact, these bacteria destroy the macrophage and slowly infect other cells in the intestine. Eventually, billions of bacteria are found in the intestines and spill out of the
infected animal in the manure.
Young animals are the most susceptible to infection. Most infections in calves are a result of ingestion of the bacteria in manure – sucking on manure-contaminated teats, licking a gate covered with manure, drinking out of a manure-contaminated pond or puddle. The bacteria can also be found in colostrum and milk of infected cows. Finding MAP in colostrum or milk is more likely if the cow is clinically sick with diarrhea and weight loss, but
cows that are infected and appear healthy can also shed bacteria in their milk. Calves can also become infected by getting the bacteria in utero from their dam. Again, this is more likely if the cow is clinically sick (showing signs of Johne’s disease, diarrhea and weight loss). MAP grow very slowly, both in the cow and in laboratory culture. The slow growth of the bacteria is one reason it takes a long time for the infected cow to show signs of disease. The slow growth also makes it difficult to quickly diagnose the disease by culturing the bacteria in manure
samples. Several things about the MAP bacteria explain the unusual nature of the disease. The fact that the bacteria live inside the cells means that they are hiding from antibodies that animals typically use to fight infectious disease. Since the blood test (ELISA) measures antibodies to the bacteria, and in the early stages of the infection the bacteria are hidden from the antibodies, the ELISA has nothing to measure, so the test results are negative. As the disease progresses, the bacteria multiply outside the cells and antibody production begins. This is why the ELISA is more accurate as Johne’s disease becomes more advanced.
Another complicating factor is that except late in the disease, bacteria are not constantly shed from the intestines in the manure. This means that a negative culture does not mean that the animal does not have Johne’s disease, only that she is not shedding at the time the sample was taken. Since the bacteria is slow growing, it takes a long time for the bacteria to multiply enough to cause disease. This results in a long time from the onset of infection in baby calves to the development of disease in adults, usually in the 3-to-7 year old range. And finally, the slow growth of MAP means it takes a long time to grow it in culture. Diagnosis of
infection by fecal culture can take up to 16 weeks. The ability of MAP to grow inside cells, to survive for a long time outside the animal, and its slow growth in the laboratory are some of the reasons the disease is so difficult to diagnose and manage.
The many faces of Johne’s Disease
Johne’s disease is an equal opportunity infection. Cattle of all breeds are susceptible. Rare breeds and
common breeds can become infected. Beef cattle, dairy cattle, working oxen, miniature cattle, show
heifers, rodeo stock and pet cows can become infected. Every animal on this page was infected with
Mycobacterium avium paratuberculosis, the bacteria that causes Johne’s disease. Every animal on this
page died, was euthanatized, or sent to slaughter because of Johne’s disease.
Beef cattle, dairy cattle, working oxen, miniature cattle, show heifers, rodeo stock
and pet cows can become infected.
Things that will decrease
the ability of MAP to
survive in the environment.
Sunlight
Drying
High (alkaline) pH
Jill
Well-known member
dragon lady said:
Where do you go to find information out about your state, I had looked up information a while back and couldn't find anything and my vet has basically no concerns. I found alot of information on the U of Wisc website, for anyone with questions, they did a really nice job and have a wealth of information.
Show Heifer
Well-known member
- Joined
- Jan 28, 2007
- Messages
- 2,221
I am going to work my cows/calves soon.....and want to make a point with other breeders around here.....Ok, I just want to know so I can use it as a selling point too!
So, how do you test for Johnes? Blood? Fecal? Test tube? The infamous purple top?
Also, what about BLV? BVD? Can all be tested with same sample (wouldn't THAT be great?)!!
I suspect no positives, but sure would like to be 100% sure and would love to promote the idea of "disease free" herd!!!
So, how do you test for Johnes? Blood? Fecal? Test tube? The infamous purple top?
Also, what about BLV? BVD? Can all be tested with same sample (wouldn't THAT be great?)!!
I suspect no positives, but sure would like to be 100% sure and would love to promote the idea of "disease free" herd!!!
AH Show Heifer - ask and ye shall receive! You can generally do all routine blood tests on serum from a red top tube (blood clots serum is what is left) - all the antibody tests can be run on serum
The attached pdf should describe the tests - then we can answer questions
consider the following -
1) Does Iowa have a program where the state pays some of the testing costs - if so and you qualify that might be the way to go - but I always recommed that people use the same lab every year for testing that way you can compare results year to year
2) If the state doesn't have a program - pick a lab you trust - I send all my personal samples to U Wisconsin - I think they are the best in the nation and I havve been using them for the last decade; all my clients samples go to the state lab because the client gets a significant cost savings and they are also top notch
3) Do not take the time and expense to test if you don't have a plan if you get positive results
4) I don't think that testing for BLV is a good use of your money (unless you are selling embryos or semen out of the US) - it is not a disease - so to speak - 1% will develop lymphoma/leukemia - so if it won't change your habits (single needle, single sleeve etc) and you don't plan to ship the BLV + ones it probably isnt worth the $. On the other hand if you are curiosu that is a different thing.
5) Re BVD - the only thing you really care about is a PI calf (cow) - I wouldn't run blood tests for BVD - you should have antibodies if you vaccinate - if you have no repro problems ear notching for BVD probably isn't worth the $ - however I would test any new critter you get ...
I don't know if Red can work her magic here but the PDF attached is about testing..hope this helps..
The attached pdf should describe the tests - then we can answer questions
consider the following -
1) Does Iowa have a program where the state pays some of the testing costs - if so and you qualify that might be the way to go - but I always recommed that people use the same lab every year for testing that way you can compare results year to year
2) If the state doesn't have a program - pick a lab you trust - I send all my personal samples to U Wisconsin - I think they are the best in the nation and I havve been using them for the last decade; all my clients samples go to the state lab because the client gets a significant cost savings and they are also top notch
3) Do not take the time and expense to test if you don't have a plan if you get positive results
4) I don't think that testing for BLV is a good use of your money (unless you are selling embryos or semen out of the US) - it is not a disease - so to speak - 1% will develop lymphoma/leukemia - so if it won't change your habits (single needle, single sleeve etc) and you don't plan to ship the BLV + ones it probably isnt worth the $. On the other hand if you are curiosu that is a different thing.
5) Re BVD - the only thing you really care about is a PI calf (cow) - I wouldn't run blood tests for BVD - you should have antibodies if you vaccinate - if you have no repro problems ear notching for BVD probably isn't worth the $ - however I would test any new critter you get ...
I don't know if Red can work her magic here but the PDF attached is about testing..hope this helps..
red
Well-known member
Oh that RED, ain't she just the NUTS!! (clapping) (clapping) (clapping)
Testing for Johne's disease
Testing for Johne’s Disease –
Tests available and what you should know about them
One of the things that make Johne’s disease such a difficult disease is that there are no perfect tests for detecting infected animals. In fact, testing may not result in a clear cut yes or no answer. Choice of tests and the strategy should be farm/client specific. There is no one recipe that is right for every producer.
Types of tests
There are basically two types of tests:
those that detect the organism (a bacteria called Mycobacterium paratuberculosis,abbreviated MAP) in manure samples and those that detect antibodies to the bacteria in blood samples.
The two most commonly used tests are the fecal culture, to detect the bacteria, and the ELISA, a blood test, that detects antibodies to the bacteria. A newer test, the “rapid fecal” (also called PCR test) is becoming quite useful in certain situations.
ELISA (pronounced ee-lye-za)
· Blood test
· Measures antibodies to bacteria that causes Johne’s
· Useful as a herd screening test
· Rapid turn around, results generally in less than one week
· Relatively inexpensive
· “False negative” results are common (negative test result in a truly infected animal)
· “False positive” results are not common (positive test result in an animal that is not infected)
FECAL CULTURE
· Culture of manure – can detect as few as 100 bacteria per gram of manure
· The bacteria are slow growing, results take up to 16 weeks
· Two types of culture
- Standard solid media culture – Readily available and results take eight to 16 weeks
- Liquid culture system - Results take four to eight weeks, but less available than standard culture
· The definitive test, considered the reference test against which other tests are compared
· More expensive than ELISA
· Positive test is considered definitive: means animal has Johne’s disease
· “False positive” results are exceedingly rare
· “False negative” results occur, but less often than with ELISA
“RAPID FECAL” also called fecal PCR
· Test done on manure
· Detects bacterial DNA
· Rapid turn around: one to two weeks
· Positive test means that animals is shedding MAP
· More expensive than fecal culture
· Less available than either ELISA or culture
Other blood tests include AGID and gamma interferon. The milk ELISA measures antibodies in milk. Histopathology on tissue detect the organism. These tests are not used commonly in beef cattle.
What you need to know to interpret the results.
In many situations, when testing for a disease, the test results say “yes this cow has the disease” or “no she doesn’t”. This isn’t often the case with Johne’s disease and is one reason it is such a frustrating disease. When interpreting the results from Johne’s testing you need to consider the test used (ELISA vs fecal); the sensitivity and specificity of the test; the prevalence of Johne’s disease on the farm (percent of herd infected); the number of animals tested; the source of the animal; and the age of animals tested.
Things to remember about Johne’s disease testing
Your test results are -
Negative ELISA or negative fecal culture
· A negative tests does not mean the animal is “Johne’s disease-free”
· A negative test does not mean the animal is not infected with MAP
· Negative results on repeated tests decreases the risk that the herd or animal is infected with MAP
· Negative results on repeated tests does not decrease the risk to zero
· A negative test result in an animal infected with MAP is called a “false-negative” test result
· False-negative test results are more common in the early stages of infection (young cattle)
Positive ELISA
· A positive ELISA in a clinically normal cow in a herd with low prevalence of Johne’s disease
may not be MAP infected – this may be a “false positive” test result
· A positive ELISA in a clinically normal animal in a herd with high prevalence of Johne’s disease
may actually be infected with MAP – this may be a “true positive” test result
· Positive ELISA results should usually be followed up with culture
Positive culture
· Positive results mean that the animal is infected with MAP – this animal has Johne’s disease
· Positive results mean that the animals is shedding MAP bacteria into the environment
· Positive results on culture mean that the animals should be culled
· Sensitivity = refers to the percentage of infected animals that test positive
· Specificity = refers to percentage of healthy, non-infected animals that test negative
· False negative = when a cow that actually is infected tests negative
· False positive = when a cow that actually is not infected tests positive
· Predictive value = probability that a given test result is correct
- Predictive value is affected by the prevalence of the disease in the herd
Test Sensitivity Specificity
ELISA 30 90
Fecal Culture 60 99.9
This chart shows that neither theELISA nor the fecal culture are particularly good at detecting infected animals (low sensitivity). So again, anegative test result does notnecessarily mean the tested cow doesn’t have Johne’s disease. However, Johne’s disease is a progressive disease, and the tests are better at detecting the disease as the disease progresses. When there are no clinical signs of disease, neither test will do a good job of identifying MAP infected animals, but as the disease progresses the sensitivity of the tests increases.
To interpret the results you need to take into account the prevalence of infection in the herd. For example, a closed herd thathas tested negative annually for ten years and then unexpectedly has a positive ELISA on one cow. This cow has previously tested negative on five annual tests. There has never been a clinical case of Johne’s disease on this farm. What does the positive ELISA mean? Given the history and the prevalence of the disease on the farm (essentially zero) and the Johne’s disease management program, the risk that this animal is infected is low and this is likely a false positive. Now think about another very different situation: an ELISA positive cow in a herd with a history of clinical disease and both
ELISA and fecal culture-positive animals. This herd also buys and sells cattle of all ages and uses cull dairy cows as embryo transfer recipients. In this case, the ELISA-positive cow, even if negative on tests in the past, likely has Johne’s disease. The cow is at higher risk of having Johne’s because of the high prevalence of the disease in the herd and the lack of any Johne’s disease prevention or control program. Johne’s disease is complicated because not only is the infection acquired at a young age (with no evidence of disease for years), but also there is no test that can tell you that your animal does not have Johne’s disease with 100 percent certainty. Testing is decreases the probability that your herd is infected and decreases the risk of selling animals infected with MAP.
Blood for Johne’s disease testing can be easily obtained from the tail vein.
Manure for fecal culture must be fresh and taken directly from the cow. Using manure from the ground is not acceptable and may be contaminated.
Testing for Johne's disease
Testing for Johne’s Disease –
Tests available and what you should know about them
One of the things that make Johne’s disease such a difficult disease is that there are no perfect tests for detecting infected animals. In fact, testing may not result in a clear cut yes or no answer. Choice of tests and the strategy should be farm/client specific. There is no one recipe that is right for every producer.
Types of tests
There are basically two types of tests:
those that detect the organism (a bacteria called Mycobacterium paratuberculosis,abbreviated MAP) in manure samples and those that detect antibodies to the bacteria in blood samples.
The two most commonly used tests are the fecal culture, to detect the bacteria, and the ELISA, a blood test, that detects antibodies to the bacteria. A newer test, the “rapid fecal” (also called PCR test) is becoming quite useful in certain situations.
ELISA (pronounced ee-lye-za)
· Blood test
· Measures antibodies to bacteria that causes Johne’s
· Useful as a herd screening test
· Rapid turn around, results generally in less than one week
· Relatively inexpensive
· “False negative” results are common (negative test result in a truly infected animal)
· “False positive” results are not common (positive test result in an animal that is not infected)
FECAL CULTURE
· Culture of manure – can detect as few as 100 bacteria per gram of manure
· The bacteria are slow growing, results take up to 16 weeks
· Two types of culture
- Standard solid media culture – Readily available and results take eight to 16 weeks
- Liquid culture system - Results take four to eight weeks, but less available than standard culture
· The definitive test, considered the reference test against which other tests are compared
· More expensive than ELISA
· Positive test is considered definitive: means animal has Johne’s disease
· “False positive” results are exceedingly rare
· “False negative” results occur, but less often than with ELISA
“RAPID FECAL” also called fecal PCR
· Test done on manure
· Detects bacterial DNA
· Rapid turn around: one to two weeks
· Positive test means that animals is shedding MAP
· More expensive than fecal culture
· Less available than either ELISA or culture
Other blood tests include AGID and gamma interferon. The milk ELISA measures antibodies in milk. Histopathology on tissue detect the organism. These tests are not used commonly in beef cattle.
What you need to know to interpret the results.
In many situations, when testing for a disease, the test results say “yes this cow has the disease” or “no she doesn’t”. This isn’t often the case with Johne’s disease and is one reason it is such a frustrating disease. When interpreting the results from Johne’s testing you need to consider the test used (ELISA vs fecal); the sensitivity and specificity of the test; the prevalence of Johne’s disease on the farm (percent of herd infected); the number of animals tested; the source of the animal; and the age of animals tested.
Things to remember about Johne’s disease testing
Your test results are -
Negative ELISA or negative fecal culture
· A negative tests does not mean the animal is “Johne’s disease-free”
· A negative test does not mean the animal is not infected with MAP
· Negative results on repeated tests decreases the risk that the herd or animal is infected with MAP
· Negative results on repeated tests does not decrease the risk to zero
· A negative test result in an animal infected with MAP is called a “false-negative” test result
· False-negative test results are more common in the early stages of infection (young cattle)
Positive ELISA
· A positive ELISA in a clinically normal cow in a herd with low prevalence of Johne’s disease
may not be MAP infected – this may be a “false positive” test result
· A positive ELISA in a clinically normal animal in a herd with high prevalence of Johne’s disease
may actually be infected with MAP – this may be a “true positive” test result
· Positive ELISA results should usually be followed up with culture
Positive culture
· Positive results mean that the animal is infected with MAP – this animal has Johne’s disease
· Positive results mean that the animals is shedding MAP bacteria into the environment
· Positive results on culture mean that the animals should be culled
· Sensitivity = refers to the percentage of infected animals that test positive
· Specificity = refers to percentage of healthy, non-infected animals that test negative
· False negative = when a cow that actually is infected tests negative
· False positive = when a cow that actually is not infected tests positive
· Predictive value = probability that a given test result is correct
- Predictive value is affected by the prevalence of the disease in the herd
Test Sensitivity Specificity
ELISA 30 90
Fecal Culture 60 99.9
This chart shows that neither theELISA nor the fecal culture are particularly good at detecting infected animals (low sensitivity). So again, anegative test result does notnecessarily mean the tested cow doesn’t have Johne’s disease. However, Johne’s disease is a progressive disease, and the tests are better at detecting the disease as the disease progresses. When there are no clinical signs of disease, neither test will do a good job of identifying MAP infected animals, but as the disease progresses the sensitivity of the tests increases.
To interpret the results you need to take into account the prevalence of infection in the herd. For example, a closed herd thathas tested negative annually for ten years and then unexpectedly has a positive ELISA on one cow. This cow has previously tested negative on five annual tests. There has never been a clinical case of Johne’s disease on this farm. What does the positive ELISA mean? Given the history and the prevalence of the disease on the farm (essentially zero) and the Johne’s disease management program, the risk that this animal is infected is low and this is likely a false positive. Now think about another very different situation: an ELISA positive cow in a herd with a history of clinical disease and both
ELISA and fecal culture-positive animals. This herd also buys and sells cattle of all ages and uses cull dairy cows as embryo transfer recipients. In this case, the ELISA-positive cow, even if negative on tests in the past, likely has Johne’s disease. The cow is at higher risk of having Johne’s because of the high prevalence of the disease in the herd and the lack of any Johne’s disease prevention or control program. Johne’s disease is complicated because not only is the infection acquired at a young age (with no evidence of disease for years), but also there is no test that can tell you that your animal does not have Johne’s disease with 100 percent certainty. Testing is decreases the probability that your herd is infected and decreases the risk of selling animals infected with MAP.
Blood for Johne’s disease testing can be easily obtained from the tail vein.
Manure for fecal culture must be fresh and taken directly from the cow. Using manure from the ground is not acceptable and may be contaminated.
Jill
Well-known member
Ok, I am in Kansas so I brought up Ks Dept of Ag and nothing comes up under Johne's, would it be under something else?dragon lady said:
Jill said:
OK - I guess I was confused (why else would I send you to Iowa??)
I would call the Kansas Dept of Ag and ask them if they have a JD Eradication Program - the web istes for this program have been notoriously slow and inaccurate - every state should have a co-ordinator of the program - usually a state DVM - I'll contact our guy and find out who your contact is...the programs have been driven by and in part funded by dairy so beef has often been ignored...when the information sheets say "the first thing to do to prevent JD is to remove the calf from the cow" most beef producers turn the whole thing off ;D
