Johnes round table

HERD HEALTH
Johne’s Disease From The Veterinarian’s Perspective
Johne’s Disease (pronounced yo-nees) is Johne’s in veterinary school. It was a case lowed a number of Angus cows with clini-
cal Johne’s to slaughter, to collect tissues usually fatal intestinal disease of rumi- with Johne’s. Also, I selected Johne’s as a and used the meat to feed the family.
Albert Johne, first described the disease Boyd H. Parr
in a dairy cow in 1895. The disease is also called paratuberculosis because its caus- ative agent is a bacterium named Myco- Parr: My f irst
need to be familiar with Johne’s Disease In this issue, the Jersey Journal presents Part 1of a two-part series with a panel of Boyd Parr, DVM, is a 1978 graduate of the University of veterinarians—researchers and practitio- Georgia College of Veterinary Medicine and operates Pied- ners included—discussing various issues mont Farm Services, Newberry, S.C. He comes from a Jer- sey farmily and was the winner of the 1971 National Jersey Youth Achievement Contest. He served on the Herd Certi- fication Subcommittee of the USAHA National Johne’s Working Group, which led development of the U.S. Volun- recount their experiences with individual tary Johne’s Disease Herd Status Program for Cattle.
cows and herds infected with Johne’s Dis- ease and discuss its control. Next month, the panel will respond to questions of par- Veeman: As a veterinarian, my first
What are the ranges of symptoms that you
have seen?
1996 on a Willamette Valley (Ore.) dairy.
Hansen: I believe I have seen the com-
This was a classic case of Johne’s: a 4-yr.- When did you see your first case of
old fresh cow, extremely thin, chronic di- Johne’s?
arrhea. We had her culled immediately.
Hansen: I saw my first case of Johne’s
Oberschlake: I have seen cows that
ing as a student on a Johne’s Disease re- Whitlock: I saw my first case of Johne’s
Oberschlake: I saw my first case of
positive, indicating exposure but not cur- rently shedding. I have also seen individu- Robert H.
als that are asymptomatic blood test nega- Whitlock
tive, but shedding Johne’s (possibly the Parr: I have seen herds that are under-
going severe stress due to other factors, Veeman: The symptoms that I have seen
Robert H. Whitlock, DVM (1965), Ph.D. (1970), received his degrees from Cornell University. He is Associate Pro- rhea) to cows that have no apparent clini- fessor of Medicine at the University of Pennsylvania Col- lege of Veterinary Medicine. To date, he has made more than 180 presentations on Johne’s Disease and since 1995, Whitlock: The youngest animal I have
has been co-chair of the National Johne’s Working Group of the United States Animal Health Association (USAHA).
about ten months of age, but this is rare, one to prioritize which cows are at greater Daniel L.
risk to transmit the disease since the test Oberschlake
quantifies the numbers of Mycobacterium paratuberculosis in the feces. Cattle with the higher colony counts are culled first vironment and spread the disease to other What is your treatment approach for a
Johne’s infected cow?
Dan Oberschlake, DVM, is a 1976 graduate of The Ohio Hansen: I do not routinely recommend
State University College of Veterinary Medicine and has treatment for Johne’s Disease once it is been practicing for 22 years. He is well-known to many diagnosed. JD is a herd problem and needs Jersey breeders, growing up with Registered Jerseys and to be addressed at the herd level. JD posi- continuing to own them today. He is affiliated with Heri- tage Animal Hospital, Ltd., Hortonville, Wis., and devotes herd and removed as soon as possible.
the majority of his time to dairy clients. He serves on the Johne’s Disease planning committee in Wisconsin.
Johne’s suspect cow, experiencing Johne’s compatible signs, such as weight loss and/ or diarrhea, I may treat her with support and if done by an approved laboratory.
therapy until we confirm or rule out JD.
with a great number of clinical cases. One Johne’s cases usually do not respond to Parr: For animals exhibiting clinical
of the most unusual was a 12-yr.-old bull, from a bull stud. He was kept in an indi- blood tests. Our local labs do not offer fe- vidual stall for his entire life, not in con- Oberschlake: My treatment approach
cal cultures. I hope that an improved or- ganism detection test will soon be avail- tested for Johne’s every six months of his the history of illness, the history of how able as a more sensitive, specific, inex- life. He became first cultured positive at slaughter to collect tissues to find the in- Donald E.
What kind of tests do you use for Johne’s?
Why?
Hansen: I use the ELISA (Enzyme
as diagnostic aids for JD. The ELISA is a good herd-screening assay that is inexpen- Veeman: Cur-
sive in Oregon, and is used to find out if JD is in a herd. On individual animals with clinical signs of JD, I use fecal cultures Donald E. Hansen, DVM, MPVM, is a 1972 graduate of and tissue biopsy. Since the ELISA test is University of California-Davis College of Veterinary Medi- cine. He is Associate Professor at Oregon State University use it more on individual cows. Interpre- College of Veterinary Medicine, a member of the National tation of results for an individual cow re- Johne’s Working Group of the USAHA, and chair of the American Association of Bovine Practitioners Food Safety and most often a follow-up test such as a test. In cows with advanced clinical signs, purchased and at what age, or raised), and the AGID test has worked well for us as a confirmatory test for JD, but it has not per- hopes of finding a treatable disease. De- formed as well in infected cows which are Whitlock: Fecal cultures provide the
not in the advanced stages of the disease.
gest considering collecting blood and fe- Oberschlake: I use the ELISA test,
since the test is essentially 100% specific cal samples for Mycobacterium paratuber- culosis and preferably following that cow to slaughter or post-mortem. If possible, available today. Fecal culture tests allow HERD HEALTH
ter, and equipment. If there is a need to nodes for cultures and histopathology.
Question your lab to find out if they have them from a herd that is free of JD, or at Parr: The most effective strategies for
controlling JD in herds focus on minimiz- If the herd is already infected, the first ing oral exposure of animals less than six may be collected via exploratory surgery.
months of age to the organism. These strat- Parr: No treatment is indicated. I rec-
prompt removal of calves from their dams, trance of JD infection. The second is us- Veeman: There is no effective treatment
against Johne’s Disease. The best option is to cull her. When I do this, it depends manure and for loading feedstuffs. In ad- upon why I’m treating her. If I’m testing source that can assure low risk or absence dition, it is a good idea to avoid spreading manure on pastures that are used for graz- ing by animals under a year of age. Other Richard A. Veeman
knowing the history of the herds of origin Veeman: Johne’s control programs re-
gressively the owners want to be. Do they want to remove it in a short amount of time (within three years)? If so, this requires aggressive testing and culling of all cows Richard A. Veeman, DVM, is a 1995 graduate of Oregon and constant testing of the fresh heifers as State University College of Veterinary Medicine and has they enter the herd, as well as all of the been practicing for four years with the Newberg Veterinary Clinic, Newberg, Ore. The vast majority, 85%, of his cli- term approach requires preventing the or- ents are dairy producers. Dr. Veeman has a strong interest in public health and the public image of the dairy industry.
and testing both existing and new cows.
The organism is spread through feces, milk on an individual basis, the individual cow early, plan to deal with test-positive cattle, needs to be culled. But, if I’m testing the plan to evaluate risk of offspring of test- preventing continued fecal-oral spread and entire herd, short-term economics must be positive cattle). Controlling the spread of taken into consideration. For example, if a Johne’s Resources On
producer has 40% of the herd test positive for Johne’s, do you cull them all at once? In Oberschlake: My recommendations
The World Wide Web
your business, as a dairy farmer, could you are to never use calf or maternity pens as Whitlock: I only recommend treating
fashion that the youngest animals are fur- thest away from manure and adult animals.
Johne’s Information Center
of the first cows I ever treated was part- Johne’s Disease on U.S. Dairy
was treated daily over a year to collect em- Operations, USDA-APHIS-VS
mediately after birth. Feed colostrum from a well-sanitized udder, Johne’s and Leu- clear the infection, which is similar to Lep- kosis negative cow. Switch to quality milk United States Animal Health
replacer or pasteurized milk. Realize that Association Recommendations on
Johne’s Disease
What are the strategies you recommend
shedding Mycobacteria paratuberculosis for controlling Johne’s ?
are infected at birth. Therefore they are Agricultural Research Service
Hansen: First and foremost, I recom-
mend farmers to activate biosecurity mea- sures to prevent the disease from entering Johne’s Disease—International
the herd. If possible, close the herd to all load of organisms they are exposed to.
Perspective
Don’t run open and short-bred heifers with infection, such as contaminated feed, wa- feeding only known-negative colostrumand milk to calves. Keep cows separated A Life Ended Too Soon For Highland Magic Duncan
Over 11 years ago on July 15, 1988, Highland Magic Duncan was laid to rest in California. At that time, he was ranked first for Production Type Index (PTI) among unless they are prepared to cull every posi- active A.I. sires and had more than 9,000 daughters in his USDA-AJCA Sire Sum- mary. He was only eight years old and should have had several more years of Whitlock: My recommendations are to
test all the adult cattle in the herd with fe- “Duncan” was, however, a victim of Johne’s Disease.
cal cultures, which will detect about three As recalled in the March, 1993 issue of Jersey Journal, by Dr. Thomas Howard, formerly with American Breeders Service and now an industry consultant from ELISA tests, if done at the same time. Pri- Poynette, Wis., Highland Magic Duncan was born into a paratuberculosis-free oritize culling of culture- positive cattle, herd. But at some time in the early stages of his life, he was in an environment first getting rid of the animals that are contaminated by the manure of an infected animal that was shedding the Johne’s to count). These animals are close to be- That he became infected was unknown until “Duncan” tested positive for M. paratuberculosis during a routine fecal culture read May 11, 1987.
threat to spread the infection in the herd.
After testing positive, Select Sires and Jerseyland Sires, which owned the bull, suspended semen sales. “Duncan” was moved into isolation and semen collec- animals as possible. If possible, cull the tions were continued. Samples from each collection were cultured for Johne’s last calf born to the cows with high colony organisms. After seven months and a series of negative tests, his semen was put back onto the market except in the state of Wisconsin, which required that semen 25% of the calves born to cows with clini- sold in the state be collected from bulls free of Johne’s Disease based on negative cal signs are infected in the uterus, prior results of fecal culture test. Sales of “Ducan” semen in Wisconsin were eventually resumed in Wisconsin on May 18, 1988 after all semen collections had been de-termined free of M. paratuberculosis. Does vaccination have a place in a
Johne’s control program?
Hansen: Vaccination may have a place
nied by stringent biosecurity measures. In Veeman: No, I do not recommend vac-
quency, and the prevalence of the disease my experience, vaccination alone does not work to control the infection. Most of the decrease the incidence of infection, shed- Oberschlake: Economic losses have
been extraordinary to some producers.
eliminate infection. Our goal is to elimi- One producer lost nearly a half of his 3- herds. Vaccination does not prevent infec- yr.-old cows to clinical Johne’s. I saw one tion, but does reduce the number of clini- Whitlock: The current vaccine for
individual lose a lawsuit against a possible cal cases of JD in a herd. Perhaps, if a herd Johne’s Disease has minimal utility for the toxic waste site because the defense pro- that has a high level of JD infected cattle control of Johne’s because it does not pre- duced evidence that Johne’s was the prob- (25% to 40%), farmers might find the vac- able cause of his cattle illness. One pro- cine helpful in reducing the risk of spread- does not eliminate shedding of the organ- ducer lost thousands of dollars because of ing infection within the herd, if they use all the other biosecurity measures at the they didn’t prove that his suspects actu- signs in vaccinated cattle. However, these ally had Johne’s through histopathology Oberschlake: Occasionally, if a pro-
cattle still will become infected and will posed to avian tuberculosis and cross-re- acted. And Highland Magic Duncan’s loss ous side effects if accidentally injected into Parr: Some recent research indicates
one’s own finger or hand. Approximately that in herds in which 10% of the cull ani- one of every 100 injections in calves may mals in the herd exhibit signs of non-re- run, if you continue vaccination it will be lead to self-injection due to movement of sponsive diarrhea, losses in the herd aver- more difficult to become Johne’s free. I the calves and inadequate restraint on the compared to non-Johne’s infected herds.
Parr: I have no direct experience with
the use of the vaccine to control Johne’s Veeman: I have had one client that had
in cattle for the concerns mentioned above.
went out of business from the devastating What kind of losses have you seen pro-
effects. They are the only ones that I per- level of infection in the herd. It only seems ducers suffer from Johne’s cases?
to delay the clinical cases and therefore Hansen: I have worked with herds that
prolong the carrier state (and shedding).
have experienced great losses (at least 40% most farms, it is very difficult to assess the impact. There are too many unknowns.

Source: http://www.usjersey.com/Reference/Johnes_1_web.pdf