Mycoplasma
Mycoplasmas are an unique group of the smallest free-living organisms, which can be found in many species of animals. Mycoplasmas where first discovered over a hundred years ago at the Pasteur Institute, since then there has been many discoveries on the way of transmission. M. mycoides subspecies mycoides (large group colony) in dairy goats has some of these symptoms: mastitis, arthritis, skin abscesses, severe reproductive tract diseases, and pneumonia. M. mycoides has been found in every continent of the world except South America and the Antarctica. The only hope for herds with this disease is through prevention and testing of animals.
Mycoplasmas are a unique because they are not a virus nor a bacteria, although some early researchers referred to the mycoplasma as bacteria in earlier studies. Mycoplasmas do not have a protective cell wall and are minimal in the area of genetic material. Due to this fact it is very hard for the hosts immunity to fight off the disease. "We think that these mycoplasmas can rapidly change the structures of their surface proteins," Rosenbusch explained. "An animal's immune system targets disease-causing bacteria for destruction by locking on the shape and size of the bacteria's surface structures. In the case of mycoplasma bacteria, these structures keep changing, the immune system is confused, and the bacteria escape."(Biotech, 1997) The mycoplasma often colonize in the respiratory tract, the bloodstream, and other mucosal surfaces. For this reason it is very hard to control due to animal's contact. Even in confinement houses animals sneeze and can spread the disease.
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Dried
mycoplasmas magnified
Dried mycoplasma cell magnified
100,000
times
100,000
times
Mycoplasmas were discovered over one hundred years ago (1898) in a cow that had arthritis and pneumonia. During this time frame veterinarians did not know what to call these items; so for 64 years they were known as Pleurpneumonia-like organisms (PPLO). After many isolations in cattle a rheumatoid patient was finally diagnosed with mycoplasma in 1939 by Dr. Swift and Dr. Brown. Even before this isolation though was the isolation in humans in 1932 from ovarian abscess. Then finally in the late fifties a viral-like strain of mycoplasma (Mycoplasma pneumoniae)was found and then they added mycoplasmas to textbooks in medical schools cirriculum. Before the last strain mentioned mycoplasmas were considered a rare oddity. After these occurrences there has been many more strains found in different species of animals. Some examples are as follows: avian, rodents, feline, canine, porcine, goats, sheep, and elephants.
Transmission is primarily through direct contact with infected goats via inhalation of expiratory aerosols from sick animals; however, organisms may also be present in urine, milk and genital secretions and contact with inanimate vectors may lead to infection. Infected animals that mature and just suffer from mastitis is 25% to 33%. If animals are shedding they could pass the disease through infected feed bunks and water troughs. Milking equipment is extremely important to keep clean and sterile because mycoplasma is also passed through milk.
Kids are greatly vulnerable because they have to consume milk to grow properly. This disease is very deadly. The morbidity and mortality rates are 90% or more pertaining to infected kids. The placenta keeps the embryo from contracting diseases until they exit and are born. After the kid is born it needs the first milk (colostrum) of their mother which if infected then the kid will definitely be infected when it nurses. Kids can also contract the disease by nose to nose contact, drinking or eating from contaminated items, and needles used for vaccinations.
Some of the symptoms of mycoplasma mycoide are mastitis, arthritis, skin abscesses, severe reproductive tract diseases, and pneumonia. Mastitis is not as common as arthritis in does, but it can become very devastating. Mastitis can cause lowered milk production causing the owner economic loss through medicine or supplying of milk. Arthritis is very debilitating causing animals to not be able to perform there normal tasks. Some examples might be as simple as eating grass which in turn produces milk for the supplier to meet demands of the consumer. Skin abscesses if open can spread through animals that don't even have mycoplasma, and they are very painful. Severe reproductive diseases again will cause the owner an economic loss because the animal cannot breed. Pneumonia not only weakens the immune defense, but causes lifelong damage to the lungs of it's victim.
To prevent the spread of mycoplasma feed the kids pasteurized milk and heat treated colostrum. An affective way to prevent the goat’s transmission of this disease is to separate the kids immediately after birth, then the herdsman can raise the kids on heat treated goat colostrum and pasteurized goat milk, cow colostrum or milk, and/or commercial milk replacers. How the caretaker would heat-treat colostrum is, “one would heat the colostrum to 133-138 degrees F and held at that temperature for one hour to inactivate it.” quoted by Nancy K. Snider at Washington Animal Disease Diag. Lab (Schalle and Everman, 1996). Then the herd manager might return the kids into the M. mycoides negative herd between weaning and their first lactation..
Due to so many ways of transmission existing via contact; therefore, we
should prevent against contact between positive and negative animals.
It is best to separate the negative from the positive thus managing two
separate herds. Another alternative
is to cull animals that are infected. A
herdsman would want to let the ground in which the infected animals were on
rest. The ground's rest doesn't
have to be long since mycoplasmas don't have a protective cell wall. The
mycoplasmas perish fast due to drying out.
When the herdsman has done all of the steps for prevention he/she will
want to have his/her animals tested annually to see if he/she went wrong
anywhere. There is one main type of
test, which is a culture. Cultures
are usually investigated by collecting milk, synovial fluid, and nasal or ocular
swabs to identify the agents involved. This
test is the most accurate; however, it takes two to three weeks to grow; if the
culture is grown properly without contamination. The kinetic enzyme link immunosorbant assay (ELISA) is not as
sensitive as the culture; therefore, it requires higher levels of contamination.
It can detect so-called
"non-cultivable" mycoplasmal strains that direct culture may miss.
The ELISA test only takes one to five days.
The
method to take blood from an animal for Mycoplasma testing is in the following
order. First, the blood collector
should get the goat in a restraint manner.
The second thing one would do is to get a cotton ball with alcohol to rub
the area to clean it of dirt after the hair is clipped off of the area.
One would need about a six cc syringes to draw the blood from cleaned
area of the animal. Usually the blood would be drawn from the neck of the goat,
by blocking off the blood vein with the thumb and middle finger, then locate the
vein above the blockage. Then the
collector inserts the needle into the vein and slowly pulls back on the plunger.
If the correct place was located then blood will begin flowing into the
syringe. After approximately 2cc of
blood has been collected, one removes the needle.
Immediately after removing the needle someone should put the blood in the
red clot tube, while another person should block off the puncture with his index
finger and middle finger. The red
blood clot tube should have that goat’s registration number to identify the
blood sample. The collector should
fill out the information on the packet which will be sent to the lab which will
be testing the goats. The
information filled out correctly will insure that the serum will not be mixed up
with other blood. If the goat that
is being tested is not registered, it’s name and tattoo or birth date can be
used for identification. One should
always have extra supplies, syringes, needles and red clot tubes, on hand in
case of an accident.
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Cleaning the drawing Drawing blood from Drawing blood neck site with alcohol. the neck. From the right front leg.
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Information properly filled out on the packet for testing.
Scripture
Verse
Isaiah 40:11 He shall feed his flock like a shepherd: he shall gather the lambs with his arm, and carry them in his bosom, and shall gently lead those that are with young. Isaiah 40:11 (KJV)
This verse means to me that the Lord cares for each and every person as
an individual just like I care for each animal as an individual and no one
animal is more important than the other is.
The good shepherd does not ignore the problems, sicknesses, or concerns
of the individual person. I do not
neglect the individuals in my herd because they are sick, but I care for them
and try to comfort them to the best of my ability. It is my desire to give every animal the chance to live up to
it’s full potential.
References
General
Mycoplasmal Biology 1997
(http://www.bionique.com/general.htm).
Merck
Veterinary Manual 8th edition, Merck & Co., Inc., Whitehouse Station NJ USA,
1998 pp 1003-1004
News
Release 1997
(http://www.biotech.iastate.edu/news_releases/April_24_97.html).
Smith,
Mary C., & Sherman, David M. Goat
Medicine Williams &
Wilkins, Baltimore,
MD 1994
pp 84-89
The
Mycoplasma Cause of Arthritis
(http://www.hitter.net/users/hwcmi/mycol.html).
Thiaucourt,
F. & Bolske, G. Contagious
caprine pleuropneumonia nad other pulmonary
mycoplasmoses of sheep and goats 1996 (http://ww.oie.int/publicat/1504/A_R15408.htm)
