The Quality Pays manual outlines the Illinois version of the 10 point milk and dairy beef quality assurance program. Ten critical control points are meant to be reviewed between the dairy producer, dairy plant field representative and the herd veterinarian. Those 10 critical control points include:
1. Practice healthy herd management.
2. Establish a valid veterinarian/client/patient
relationship (VCPR).
3. Use only FDA-approved over-the-counter
(OTC) or prescription (Rx) drugs with a veterinarian's guidance.
4. Maintain milk quality.
5. Implement an effective
mastitis management program to maximize milk production.
6. Administer all drugs properly
and identify all treated animals.
7. Maintain and use proper
treatment records on all treated animals.
8. Use drug residue screening
tests.
9. Implement employee/family
awareness of proper drug use to avoid marketing adultered dairy products.
10. Complete the milk and
dairy beef residue prevention protocol annually.
The "Quality Pays" manual is unique in that it also contains a concise and efficient record system. Dairy producer not currently using a treatment record system are encouraged to begin the process with this manual. The record pages in this manual will help producers comply with current and future antibiotic and drug treatment monitoring programs.
For Illinois dairy producers, a "Quality
Pays" manual has been included with this edition of the Quality Milk Issues.
For anyone else interested in learning more about the Illinois Quality
Pays program, please use the information in the header above or send an
email to me at <dairydoc@uiuc.edu>.
The Illinois Department of Public Health attended meetings with the Illinois Milk Producer's Association in 1995 and 1996 to develop plans for drug residue avoidance training opportunities for dairy producers, dairy field representatives and veterinarians. The Department believes that the decrease in drug residue violations in 1998 and 1999 are at least partially due to sponsored training programs. These programs produced a greater awareness among dairy producers, their milk plant field representatives and their veterinarians in methods to reduce dependence on antibiotic solutions and prevent residue violations.
Drug Residue Alternative Penalty Fund
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Balance
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** $8,794.96
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$8,794.96
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$32,490.04
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$750.00
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$40,535.00
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$34,129.32
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$9,680.95
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$64,983.98
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$17,986.32
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$12,300.00
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$70,670.30
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$6,985.64
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$12,047.13
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$65,608.81
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| * The provision for alternative penalties to 2 or 4 day permit suspensions became effective in 8/95. | |||
| ** The budget appropriation for spending from the fund became effective in 7/96. | |||
by Duane N. Rice, Extension Veterinarian
University of Nebraska Cooperative Extension
The dairyman is generally aware of clinical mastitis because it can be seen as changes in the milk, swollen udder and other signs exhibited by the cow. Compared with subclinical mastitis, clinical mastitis is much less costly, is of short duration, tends to be an individual cow problem, and is detected without special tests.
Unfortunately, the apparently healthy cow can harbor subclinical mastitis, which creates tremendous loss in milk production. A cow with subclinical mastitis does not have a swollen, painful udder or abnormal looking milk. Infection is present, however, creating an elevation of the somatic cell (white blood cells and epithelial cells) count in the milk. These unseen infections are detected by several methods, including the direct microscopic somatic cell count (DMSCC), the Wisconsin Mastitis Test (WMT), and the California Mastitis Test (CMT). The DMSCC and WMT are laboratory tests but, fortunately for dairymen, the CMT is a cowside test that can be a valuable tool, yielding rapid results.
Important Information from CMT Results
The use of the CMT on the entire herd at monthly intervals can be extremely useful as an aid in detecting herd mastitis problems. Individual and total quarter infections can be determined and, with proper records, the level of herd mastitis can be monitored. This test yields information that can aid in determining faulty milking procedures or equipment function, as well as the effectiveness of teat dips and dry cow treatment programs.
How the CMT Works and What It Means
Mixed with milk, the CMT chemical or reagent
reacts with leucocytes (white blood cells) that are usually present in
large numbers when an infection occurs. Whenthis reaction occurs, the reagent-milk
mixture thickens or gels in proportion to the number of leucocytes present
and indicates the severity of the inflammation. The greater the reaction,
the higher the CMT score. The scoring of the CMT will vary somewhat, depending
upon the skill of the person reading the result and the method
used to conduct the test. Uniformity in
technique is necessary if results are to be comparable.
The scoring of the CMT reactions shown in Table I indicate approximate somatic cell counts. As you can see, the count for each consecutive higher score is approximately three times that of the previous count.
Table I. CMT reaction scores.
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(cells per milliliter) |
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Advantages of the CMT
The CMT is fairly accurate
in measuring somatic cell concentration in milk, correlating well with
other tests.
It is sensitive.
Primarily developed for
sampling quarters, it can also be used on "bucket" and "bulk tank" milk
samples.
Foreign material, such as
hair or other matter, does not interfere with the test.
It is inexpensive.
The test is simple, and
little equipment is needed.
Easy clean-up after each
test--simply rinse with water.
Environmental temperature
changes have little effect on the CMT as long as the milk has been refrigerated
and is not over two days old.
Herd mastitis levels can
be estimated from tank CMTs. A CMT of 2 or 3 on tank milk indicates a probable
high percent of infected cows.
Disadvantages of the CMT
Scoring the test may vary
between individual testers.
It is necessary to be as
consistent as possible to insure uniform results. Scores represent a range
of leucocyte
content rather than an exact count.
False positive reactions
occur frequently on cows that have been fresh less than ten days, or on
cows that are nearly dry. These animals should be tested closer to the
middle of the lactation.
Occasionally, acute clinical
mastitis milk will not score positive due to the destruction of leucocytes
by toxins (poisons) from the infecting organism.
Conducting the CMT
Testing individual quarter samples requires the use of a plastic paddle having four shallow cups marked A, B, C and D for easy identification of the individual quarter from which the milk was obtained.
Approximately 1/2 teaspoon (2 cc) of milk is tested--the amount usually left in the cups when the paddle is held nearly vertical, or in an upright position. An equal amount of the CMT reagent is added to the milk. The paddle is then rotated in a circular motion to thoroughly mix the contents. Score in approximately ten seconds while still rotating. It is important to "read" the test quickly as the reaction tends to disintegrate after about 20 seconds. Rinse the paddle thoroughly with water and it is ready for the next test.
The proper interpretation of the 10 second reading is described in Table II. To become proficient and consistent, practice this test on milk of known cell count.
Table II. Interpretation and Scoring of
the CMT test.
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Mixture remains liquid, homogeneous, with no evidence of thickening. |
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The slight thickening that forms is seen best by tipping the paddle back and forth and observing the mixture as it flows over the bottom of the cup. Trace reactions tend to disappear with continued rotation of the paddle. Read at 10 seconds. |
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A distinct thickening of the liquid forms, but there is no tendency toward a gel formation. With some milk, the thickening may disappear after prolonged rotation of the paddle (20 seconds or more). Read at 10 seconds. |
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Mixture thickens immediately, and a gel formation is suggested. As the mixture is swirled, it tends to move in toward the center, exposing the bottom of the outer edge of the cup. When the motion is stopped, the mixture levels out and covers the bottom of the cup. Read at 10 seconds. |
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A gel is formed, which causes the surface of the mixture to become elevated like a partially fried egg. There is usually a central peak that remains projecting above the main mass, even after the rotation of the paddle is stopped. |
Treatment of CMT Positive Cows
During lactation, it is not generally recommended to treat all subclinical mastitis that is detected by the CMT alone. If you suspect that a subclinical case of mastitis may progress to clinical, rather than receding, prompt therapy should begin. Clinical cases (obvious mastitis) require early therapy for a long enough period of time to completely knock out the immediate infection. Laboratory culturing of milk from these quarters is necessary to provide the required information to prescribe proper therapy.
The CMT provides information on the individual cow and can provide insight into the total herd status. By periodically recording your CMT results, you can monitor herd levels and investigate the possible causes early when results show elevated CMT scores from one test to the next.
Conclusions
Regardless of CMT results, it is recommended
that you maintain a carefully planned mastitis control program consisting
of:
Proper machine function
and milking procedure.
Hygiene and use of effective
teat dips.
Culture and treatment of
clinical cases as recommended by your veterinarian.
Dry cow treatment--all cows,
all quarters--under the direction of your veterinarian.
Culling of problem cows.
Cull cows with repeated clinical flare-ups and with a CMT score of
2 or more, in two or more quarters.
by Richard L. Wallace, Dairy Extension Veterinarian
The Illinois Johne's Disease Task Force has met on several occasions to determine the best course of action for Illinois dairy and beef cattle producers. This group has members representing dairy and beef producers, veterinarians, regulatory agencies and allied industries.
There are two basic Johne's programs; producers trying to certify that their herds are clean and herds that are infected and trying to eradicate the disease. Official tests approved for the programs include the USDA-licensed ELISA blood test and the fecal culture test. Both tests have a tendency to miss some infected cows, but positive test results are nearly always correct.
In order to enter either program, a producer must blood test at least 30 cows in their second lactation or greater. Results from this herd screening will determine which program and at what level the herd can be certified. If there are not 30 second lactation or greater cows, then first lactation cows must be tested as well. Suspect results can be confirmed by fecal culture.
If all samples are negative the herd can qualify for Level 1 Certification and the herd would be considered a lower risk for spreading the disease. The next step is to obtain a whole-herd negative blood test followed by a whole-herd negative fecal culture to achieve Level 2 and then Level 3 status. Level 4 status can be attained by completing a second whole-herd negative blood test. These herds are considered the lowest risk of infection.
If the initial negative test of 30 cows
occurred in a herd known to have Johne's infected cows, the herd would
be classified Level A and qualify for Level 1 status. If at any time a
positive animals are detected, the herd would lose its Level 1 qualification.
If the initial test had less than 5 percent positive samples, the herd
would be classified at Level B. If between 5 and 15 percent are positive,
the herd is classified Level C, and greater that 15 percent is at Level
D. Untested herds are assigned Level 0 status and are considered the highest
risk for spreading Johne's disease.
SPRINGFIELD, IL - Mr. Jim Kagel, Woodstock, IL has received the distinction of being the first dairy herd in Illinois to qualify for certification at Level 1 under the Illinois Voluntary Johne's Disease Certification Program. Mr. Kagel had a complete, negative herd test of 61 animals.
The Illinois Voluntary Paratuberculosis (Johne's disease) Certification Program was established on January 1, 1998. The program offers owners of cattle, bison, buffalo, sheep, goats, llamas, deer and elk the opportunity to test and certify their herds or flocks based on the probability of the herd or flock being free of Johne's disease. Under the original program, cattle producers needed a complete negative serum test on all animals in the herd 24 months of age and over to qualify for the program. Effective July 1, 1999, cattle herds will be able to enter the program upon a negative serum test of 30 adult animals in the herd. For all other species, an annual complete herd negative fecal culture is required. As of June 1, 1999, three goat herds and one elk herd are also certified under this program.
Johne's disease, or paratuberculosis, is an infectious, bacterial dysentery affecting cattle, sheep, goats, deer and elk. It is a chronic wasting disease that does not respond to treatment and there is no cure. Infection occurs with the ingestion of the Johne's bacteria through feed or water contaminated with infected feces, or from bacteria on the teat or udder of the mother.
Source-Illinois Department of Agriculture
Twenty three Wisconsin dairy herds containing 1653 cows were analyzed for associations between subclinical Johne's disease and milk production parameters including somatic cell count. All herds had a history of Johne's disease and above average milk production.
The average herd size was 72 cows with a range of 34 to 220 cows. DHIA records were used to evaluate milk, fat, and protein production and somatic cell count. Summarizing all herds, the average 305 ME milk production was 20,785 pounds (range 17,720-25,375 pounds). Mean linear somatic cell score was around 3.
All adult cows were tested for Johne's disease with the USDA licensed ELISA blood test. The dynamics of this test suggest that it will detect roughly half of the truly infected cows. The percent of cows testing positive within each herd ranged from 4.2 to 28.6 percent with an average of 10 percent. Overall there were 147 test positive cows and 1506 test negative cows in this study.
The 305 ME milk production for the test positive cows was 830 pounds less than that for the test negative cows. No significant differences were found in lactation average linear score, fat test nor protein test. When milk production from current lactations were compared to milk production from first-previous lactations for test-positive versus test-negative cows, significant differences were found only in the mean differences between cows in their second lactation and the first lactation.
These results indicate that subclinical Johne's disease infection, as diagnosed by the licensed ELISA test, was associated with a 4 percent reduction in milk production. This study does not establish a cause and effect relationship, by only an association. The production loss may be slightly underestimated because cows with false-negative test results were included in the control group.
Production losses in subclinically infected
cows add to the already substantial costs of clinical Johne's disease infection
to the dairy industry. Previous surveys estimate that 34 percent of Wisconsin
herds have infected cows. From this data, it can be assumed that the prevalence
within herds is nearly 5 percent. This study suggests that subclinical
Johne's disease currently costs the Wisconsin dairy industry 14.3 million
pounds of milk per year with a value approaching $2 million.
Studies show that predipping can help control environmental mastitis and the practice is being widely used by dairy producers. The National Mastitis Council Teat Dip Residue Task Force addressed the question of milk residue from both pre- and post-teat dipping. Of particular concern to the committee is residual teat dip, when used prior to milking, into the milking unit.
Predipping does not necessarily mean that
teat dip residue will be in the milk. When done properly, predipping can
be of great importance to herd health while minimizing the risk of contaminating
milk with teat dip residue.
Here are some tips for predipping:
1. Use only a teat dip which is listed with the Food and Drug Administration and has predipping instructions on the label. Information about a product can be obtained from the manufacturer.
2. Follow proper application procedures:
a) Pre-clean
teats as necessary.
b) Fore-strip
(may be done before or after teat dip).
c) Apply teat
dip. Allow for required contact time.
d) Dry teats
with single service paper towels.
e) Attach milking
unit.
Milking predipped teats that have been
properly dried has many benefits:
* Reduces the possibility
of residues in milk from surface drainage of excess teat dip.
* Sanitizes the teat prior
to milking.
* Reduces environmental mastitis.
* Minimizes liner slippage.
Attitude Makes A Difference
Proper milking procedures and a positive
attitude are required to minimize mastitis and maximize quality production
from a milking herd. Milking should be done by responsible and conscientious
persons. Good management dictates that the person milking must be constantly
alert to conditions that may spread mastitis organisms from cow to cow.
Provide a Stress Free Environment
A consistent operating routine for bringing
cows and milking machines together is essential. Cows that are frightened
or excited before milking may not let their milk down in spite of an effective
preparation routine. Hormones are released into the bloodstream during
periods of stress. These hormones interfere with normal milking procedure
and the animal's resistance to disease, including mastitis. A milking environment
that routinely causes stress to cows may predispose cows to a greater rate
of mastitis infection.
Clip Udders For Cleanliness
Well clipped udders reduce the amount
of dirt and manure that can contaminate milk. Udders with long hair are
difficult to clean and dry. Milking wet and/or dirty teats increases the
risk of high bacteria counts in the milk and increases the rate of new
cases of mastitis.
Check Foremilk and Udder For Mastitis
Presence of mastitis can be detected by
palpating the udder for swelling, heat, and/or "knots", and by using a
strip cup or plate to examine foremilk of each quarter of each cow prior
to every milking. Correct use of the strip cup can be a valuable aid in
detecting symptoms of mastitis such as clotty, stringy, or watery milk.
Milk should never be stripped into the hand. This practice spreads mastitis
organisms from teat to teat and cow to cow. Forestripping may aid in preventing
new infections by flushing mastitis organisms from inside the teat.
Good Massage Increases Production
When teats and the lower part of the udder
are massaged, a signal is sent to the brain which secretes the milk letdown
hormone, oxytocin, into the blood stream. The hormone is then carried to
the udder where it acts on muscle cells to "squeeze" milk out of the milk-secreting
tissue. Massage of all teats is better than massage of only one or two
teats and physically squeezing each teat will reduce the amount of milk
left in the udder at the end of milking. Large amounts of milk left in
the udder increase frequency of clinical mastitis in infected quarters.
Fright and Flight Syndrome
Positive signals to the brain cause release
of oxytocin and milk letdown. However, signals are also sent to the animal's
brain when she is frightened or experiences pain. These signals cause the
release of adrenalin which interferes with the action of oxytocin making
it difficult to obtain maximum milk yield.
Washing Teats in a Parlor
In milking parlors, a common method of
washing is to use a spray hose with sanitizing solution and hands to remove
debris from teats. Only the teats should be washed, as wetting the whole
udder makes it difficult to adequately dry the udder before milking machines
are attached. Milking wet udders and teats may lead to increased mastitis
and bacteria counts.
Washing Teats in a Stanchion Barn
In stanchion barns, use a sanitizing solution
in a bucket and individual paper towels to prepare udders and teats. Individual
paper towels are highly recommended as sponges and cloths frequently increase
transmission of mastitis organisms to uninfected quarters and cows.
Milk Only Dry Teats
Regardless of how the udder and teats
are prepared, they must be dry when milking machines are attached. Dry
with individual towels to prevent cross contamination of quarters and cows.
Without thorough drying, many organisms remain on the teats. During
milking, water containing organisms can drip down the sides of teats and
may be drawn into teat cups, exposing the teat ends to bacteria. Milking
wet teats causes mastitis and lowers milk quality.
Machine-Induced Mastitis
Most machine-induced infections occur
near the end of milking. Toward the end of milking, when a teat cup liner
slips as the liner opens, small droplets of milk may be propelled against
the end of the teat. These droplets may contain mastitis organisms and
may enter the teat. Since milk flow is minimal, chances of the organisms
being flushed out of the quarter are reduced and infections may result.
Removing The Milking Unit
Teat cup removal is more important than
unit attachment. Vacuum should always be shut off before teat cups are
removed. The practice of pulling the unit off under vacuum should be avoided
because it may cause a machine-induced infection in one of the other quarters.
How should you handle a quarter that milks out ahead of others? In
general, if the teat cup will stay on the teat without slips, it should
be left on because removal of the cup stimulates liner slip and may cause
machine-mastitis.
Dip Teats Immediately After Unit
Removal
Dip each teat in a commercial preparation
after every milking. Teat dip destroys organisms on teats, prevents organisms
from growing inside the end of the teat, and eliminates organisms already
living inside teat ends. A variety of teat dip products are commercially
available and are known to reduce new infections by more than 50 percent.
Ask the dealer for research results that prove the product is effective.
Use Clean Dip and Keep Dipping
Maintain teat dip cups in a clean and
sanitary manner and never pour remaining dip back into the original container.
When dip becomes cloudy or contaminated with bedding or manure, discard
the remaining dip, clean cups thoroughly, and refill with fresh dip. Always
continue dipping, even during cold weather. If the temperature is below
10 F or there is a strong wind chill factor, allow teat dip to remain
on teats for at least 30 seconds and then wipe off excess dip with individual
paper towels to reduce chapping and freezing of teats.
Which Cows First?
The order in which cows are milked can
have an impact on controlling the spread of mastitis, although it is recognized
that herds may be grouped by other economic or management criteria. By
milking first lactation cows first, second and later lactation cows with
low somatic cell count second, cows with high somatic cell counts third,
and clinical mastitis cows last, the chance of spreading mastitis organisms
from cow to cow is reduced.
by Richard L. Wallace, Dairy Extension Veterinarian
For over 50 years, antimicrobials have been used on dairy farms along with other drugs to treat and control disease, and to improve animal productivity. Recently, antibiotics have received an increasing amount of attention. The main concern today seems to focus on the concept that use of antimicrobials on farms may contribute to antimicrobial resistance in human pathogens.
Issues pertaining to drug-resistant human pathogens are being discussed within the US Centers for Disease Control and Prevention (CDC) and Center for Veterinary Medicine (CVM). Both the CVM and CDC have agreed on the following points: 1) there is a legitimate need for both older and newer antimicrobial drugs in animal agriculture, 2) the bulk of Salmonella, E. coli O157, and Campylobacter infections in humans in the U.S. originate from food of animal origin, and 3) the use of antimicrobials in animals will cause resistance to develop, and there is a potential that resistant Salmonella, E. coli, and Campylobacter will be transferred to humans through food.
Voluntary ban on aminoglycoside use in cattle
In July 1998, the Am Veterinary Medical Assoc (AVMA) joined the AABP and several state associations by passing a resolution to ban the use of aminoglycosides in cattle. The resolution supports a voluntary ban on the extra-label use of aminoglycoside antibiotics, particularly gentamycin in cattle. If used, in order to comply with current regulations, extra-label drug use must include a sufficiently extended withdrawal period so that no residues are found in meat or milk products. Dairy producers using aminoglycosides and veterinarians prescribing the use of aminoglycosides will be in indefensible positions should residues be found.
Old tetracycline receives new milk cow clearance
The FDA has approved the new animal drug application for the use of Liquamyacin LA-200 injection in lactating dairy cattle. For the first time, dairy producers have an antibiotic approved for systemic use when treating acute metritis. Milk taken from cows during treatment with LA-200 and for 96 hours after the last treatment must not be used for food.
Coincident with this new approval comes an amended tolerance for the combination of oxytetracycline, chlortetracycline and tetracycline residues in milk. The CVM has reevaluated toxicity and metabolism data used to establish tolerance levels. The previously accepted safe levels for oxytetracycline, chlortetracycline and tetracycline in milk were 30, 30, and 80 ppb respectively for a sum of residues of 140 ppb. The new combined tolerance level for tetracycline in milk is 300 ppb. With this increase, there are currently no FDA approved rapid screening tests for tetracyclines in raw co-mingled milk. New testing procedures are being developed.
Fluoroquinolone receives approval from CVM
Enrofloxacin, a fluoroquinolone has been approved by the FDA for the treatment of bovine respiratory disease associated with Pasteurella and Haemophilus. The product, Baytril 100 Injectable Solution remains a prescription product. Baytril is not for use in cattle intended for dairy production or in veal calves. Extra-label use of fluoroquinolones in food animals is still prohibited by the FDA.
Fluoroquinolones are administered in human
medicine for refractory cases where other antibiotics have proven of little
or no use. The company has voluntarily committed to the FDA to immediately
take action, including removal of the Baytril from sale, should the FDA
conclude that there is a risk to public health.
Dawn E. Morin, DVM, MS
Assistant Professor, Food Animal Clinical
Medicine
College of Veterinary Medicine
Mycoplasma are unusual bacteria that lack a cell wall. In recent years, several species of Mycoplasma have been identified as mastitis-causing pathogens of dairy cattle throughout the world. Mycoplasma are routinely isolated from problem herds in California, Florida, and New York, and Mycoplasma mastitis has now been recognized in most US states. The number of Mycoplasma-infected herds in Illinois is not known, but is likely to be between 1 and 6%, based on results of bulk tank surveys conducted in other states. In problem herds, up to 70% of cows may be infected, resulting in substantial economic loss.
Cows infected with Mycoplasma may exhibit either clinical or subclinical mastitis. Those with clinical mastitis usually have abnormal-appearing milk (often thick and sometimes brown, tan, or orange) and an inflamed (swollen, hard) udder, but are seldom sick. Multiple glands of a cow may be affected, and milk production is reduced. Occasionally, respiratory disease or joint infections accompany mastitis or are present in other animals in the herd. Cows with subclinical mastitis have normal-appearing milk and no visible changes in the udder, but have high somatic cell counts (SCC) and reduced milk production.
A diagnosis of Mycoplasma mastitis is made by culturing milk. Unfortunately, Mycoplasma do not grow on media routinely used to culture other mastitis pathogens. Therefore, Mycoplasma testing must be specifically requested. Growth usually takes 4 to 10 days, much longer than for most other mastitis pathogens.
Antibiotic treatment of Mycoplasma mastitis is unrewarding and not recommended. Although susceptibility tests often indicate that the organism is sensitive to antibiotics such as tetracycline or erythromycin, these drugs do not cure the infection. None of the commercially-available mastitis tubes are labeled for treatment of Mycoplasma mastitis, nor would they be effective. Failure to recognize that episodes of clinical mastitis are caused by Mycoplasma can result in prolonged, inappropriate antibiotic usage and increased risk of antibiotic residues. Spontaneous resolution of Mycoplasma infection occurs in some cases, but time to resolution is highly variable. Chronically infected cows, especially those with persistent or repeated bouts of clinical mastitis, must be culled.
How to control Mycoplasma mastitis:
Mycoplasma mastitis can be introduced into a herd by purchasing infected cows or heifers. To avoid this, several steps can be taken. If purchasing animals from a known source, request to see SCC records for the herd. Avoid purchasing cows from herds with high (> 400,000 cells/ml) bulk milk SCC, or cows with recent high SCC or clinical mastitis. If such cows are purchased, culture their milk for Mycoplasma and other contagious pathogens (Streptococcus agalactiae, Staphylococcus aureus) before mixing them with the herd. If SCC records are not available, the California Mastitis Test (CMT) can be performed on purchased animals and milk from those testing positive cultured. It is easier to avoid introducing Mycoplasma mastitis than to eradicate it once it is established.
Because Mycoplasma mastitis spreads from cow to cow at milking time, good milking hygiene practices are essential for controlling it. These include wearing gloves, using individual towels, monitoring cows for clinical mastitis and milking those cows last, using an approved germicidal teat dip after milking, and maintaining a properly functioning milking machine. These procedures are also recommended for control of Streptococcus agalactiae and Staphylococcus aureus. Because Mycoplasma can be shed in respiratory and urogenital secretions and survive in manure, urine, or water, providing clean, dry, comfortable housing is also important.
If Mycoplasma mastitis becomes established, it can be controlled only by repeated culturing of all cows in the herd and strict segregation or culling of infected individuals. The costs associated with culturing, culling, and increased labor are substantial, and compound the underlying costs of reduced milk production, loss of quality premiums, and discarded milk.
Suspect Mycoplasma mastitis if:
The bulk tank SCC is high or increasing
and other mastitis pathogens are not isolated from milk of cows with high
SCC.
Clinical mastitis incidence is high or
increasing, especially if cows have more than one gland affected, signs
do not resolve with routine antibiotic therapy, and other mastitis pathogens
are not isolated from the milk.
If Mycoplasma mastitis is suspected in
a herd, begin by culturing the bulk tank on several occasions. Repeated
negative cultures indicate absence of infected cows. If Mycoplasma is isolated
from the bulk tank, the isolate should be submitted for typing to make
sure it is a pathogenic strain; then a whole herd culture is indicated
if control is desired.
Mike Hutjens, PhD
Extension Dairy Specialist
University of Illinois
Over the last five years (1992-1997), the number of dairy operations in Illinois has declined 30 percent to 1781 dairy farms. In spite of this decline, the dairy industry contributes over 350 million dollars to the state's economy. Unfortunately, few political figures and policy makers seem to care if Illinois loses a dynamic agricultural industry that has the potential to create new jobs for the state. Currently, more than 60 percent of the dairy products purchased by Illinois consumers are imported from other states. Feed companies, veterinarians, milk machine dealers and cooperatives are asking the question "Does Illinois have a viable dairy industry?"
For those of us committed to the survival and growth of the Illinois dairy industry, our answer is "Yes," if we can accomplish the following:
1. Each and every Illinois dairy farm must be economically viable (one million pounds of milk per person drawing a salary from the dairy farm, debt load below $2500 per cow, and annual return on assets of 5 to 9 percent).
2. Dairy farms with 40 to 400 cows can compete and be economical, but different herd sizes must have different strategies (milk yield per cow for herds with less than 40 cows must be 25 percent above the state average of 16,000 pounds per cow per year for the Holstein breed).
3. The Illinois dairy industry must become pro-active. We must encourage new dairy farms to enter the Illinois dairy industry. Producers must become active in support of favorable livestock rulings on labor, taxes and manure regulations. Illinois Milk Producers Association must become as visible as the Illinois Pork Producers Association in Springfield, Urbana, Chicago, and across the state of Illinois.
4. The number of dairy cows must stabilize over 150,000 (currently Illinois has 145,000 cows) to encourage the infrastructure to remain and expand.
Livestock and Illinois are synonymous with its economical feed resources, favorable weather, strong infrastructure, rich history and background in animal husbandry. But, we can not assume or take the Illinois dairy industry for granted. Dairying is an aggressive agri-business in the US and world. Only the economically strong will remain. The University of Illinois is here to assist, support, and co-lead.
See you at the 1999 Illinois Dairy Days!
In January 1998, State of Illinois Legislature and the Illinois Department of Agriculture passed the Diseased Animal Act. Regulations regarding the Paratuberculosis (Johne's Disease) Certification Program are included with this issue. A second informational brochure, which explains Johne's disease and answers several frequently asked questions, is included as well. The Illinois Johne's Disease Task Force has met on several occasions to determine the best course of action for Illinois dairy and beef cattle producers. This group has members representing dairy and beef producers, veterinarians, regulatory agencies and allied industries. Watch for future meetings and seminars on Johne's disease control.
Quality Pays, Illinois Milk Safety and Quality is an adjunct program to the Milk and Dairy Beef Quality Assurance Program. Illinois Department of Public Health, Division of Food, Drugs and Dairies, in conjunction with the University of Illinois Extension will present this new consultation guide and record system to Illinois dairy producers in 1998-99. Watch for information regarding up coming meetings.
During the spring of 1998, an alfalfa scissor clip project was completed by several animal and crop system Extension educators. This project involved bi-weekly sampling of alfalfa fields from 28 locations throughout the state. Producers were able to rapidly receive alfalfa quality reports and to determine the optimum time to begin first harvest. Results can be found on the World Wide Web at: www.cvm.uiuc.edu/ceps/wallace/pifqp/alflafa.html
Richard L. Wallace, Editor
Dairy Extension Veterinarian
[abstracted from Paul Damian, Arthur Craigmill and Jim Riviere, FARAD Digest, JAVMA, Oct. 1, 1997]
A survey of food animal veterinarians found that 93% reported using nonsteroidal anti-inflammatory drugs on their patients. Sixty percent of those surveyed reported using these drugs more than once a week. Dairy practitioners use them more often than beef practitioners and Banamine is used more frequently than Aspirin, Bute, Ketofen or other similar drugs.
Currently, none have been approved for
use in food animals in the U.S. Any use of these drugs would be considered
extra-label use and may only be used within the confines of a valid veterinary/client/patient
relationship. Veterinarians and producers need to be aware of FARAD-recommended
milk and meat withdrawal times. Larger doses or longer treatment regimes
would require extended withdrawal periods.
|
|
|
|
|
| Aspirin | 3-4 boluses q 6 hrs | 24 hours | 1 day |
| Ketofen | 1.5 mg/lb, IV or IM, q 24 hr, for 3 days | 24 hours | 7 days |
| Banamine | 1.0 mg/lb, IV or IM q 24 hr,
3-5 days |
24 hours | 10 days |
| Bute | 6 g/animal IV or IM
2 g/hd/day orally |
96 hours
120 hours |
12 days
21 days |
| Dipyrone | Not approved for use in dairy cattle or food animals | Not legally available in the United States |
[abstracted from Joseph M. Smucker, Team Leader Milk Safety Branch, FDA-CVM, Apr. 16, 1998]
The FDA Center for Veterinary Medicine approved Schering-Plough's Nuflor® Injectable Solution on May 31, 1996. Since the approval date, numerous questions relating to the use of Nuflor on dairy farms have come to the attention of FDA.
Nuflor contains the new animal drug florfenicol. Florfenicol belongs to the same antibiotic family as chloramphenicol, but is chemically different and is not linked to human toxicity concerns. The FDA prohibited the use of chloramphenicol in 1984. Nuflor is not related to fluoroquinolone class of antibiotics. FDA prohibited the extra-label use of fluoroquinolones in May 1997.
The labeling for Nuflor bears the prescription (Rx) legend. Nuflor is intended for treatment of cattle pneumonia and shipping fever. Nuflor is labeled for use in all classes of cattle except female dairy cattle 20 months of age or older and veal calves. The product has a 28 day meat withdrawal period from the last treatment. The FDA has not established a milk discard time, tolerance or safe level for Nuflor in milk. If Nuflor is found on dairy farms stored on the non-lactating shelf, it must be labeled with the name and address of the prescribing veterinarian because it is an Rx product.
Currently there are no prohibitions under FDA's Animal Medicinal Drug Use Classification Act (AMDUCA) on veterinarians prescribing Nuflor for use in lactating dairy cattle. If prescribed for extra-label uses or if found on the lactating drug shelf on farms, the product must bear an extra-label by a licensed veterinarian that specifies; their name and address, directions for use and the veterinarian's prescribed withholding times for meat and milk, even if zero, cautionary statements if needed, and active ingredients.
The Charm II chloramphenicol test is reportedly
capable of detecting residues of Nuflor in milk at 25 ppb. If levels of
Nuflor are present in milk to result in a positive on the official Charm
II test, that milk is considered to be violative under the provisions of
the PMO. Any residue of Nuflor in milk indicates the product was used in
an extra-label manner. AMDUCA does not allow for any levels of Nuflor
in milk because no safe or tolerance level has been established. Any positive
screening test result conducted by the industry must be reported to the
state regulatory authority for follow up.
[abstracted from CVM Update, FDA, Jan. 22, 1998]
Dairy producers are now prohibited from feeding protein feed ingredients made from rendered animal tissue. The rules, issued in Aug. 1997 by the FDA, are designed to prevent the establishment and spread in the U.S. of bovine spongiform encephalopathy (BSE). The disease, known as "Mad Cow Disease," has been found in European cattle herds, but has not been diagnosed in the U.S.
The rule bans most types of protein made from mammalian tissue, like meat and bone meal made from cattle byproducts. Cattle may become infected with BSE when they eat contaminated protein products made from rendered diseased animals.
Feed manufacturers, protein blenders, and rendering companies are required to label any feeds or feed ingredients containing prohibited material with the warning statement, "Do not feed to cattle or other ruminants." FDA can take action against a company selling prohibited material that does not have the warning label on it.
The rule has several provisions that apply
to dairy producers:
You must watch for the warning
label, and avoid using any prohibited feed in cattle rations.
If you suspect that feed
may contain prohibited ingredients, do not accept it until you are sure
it does not. Buy feed products only from companies that comply with the
new rules.
If you mix feed for
both cattle and non- ruminant animals (such as hogs and poultry) and you
use prohibited material in the non-ruminant feed, you must either use a
completely separate mixer for the cattle feed or carefully clean out your
mixer to be sure no prohibited material contaminates the cattle feed.
Even if you do not mix your
own feed, but purchase feed for both cattle and non- ruminants, you must
take steps to make sure that any prohibited material intended for your
non- ruminant animals is not accidentally fed to your cattle.
You must keep records for
a minimum of one year concerning all animal protein ingredients you buy
and use with your cattle. The copies must be available for government inspectors.
Keep at least one representative copy of the label from each type of feed
you buy.
The complete update can
be found at: www.fda.gov/cvm/fda/infores/updates/bse/dairybeefprod.html
Richard L. Wallace, DVM, MS
Dairy Extension Veterinarian, University
of Illinois
Over 100 mastitis kits distributed to Illinois dairy farms by the 4-month old Herd Mastitis Diagnostic Service have been returned to the Urbana Veterinary Diagnostic Lab. More than 75% of herds submitting samples have one or more cows infected with Staphylococcus aureus (to obtain a kit contact Veterinary Extension at 217-333-2907).
Staphylococcus aureus has long been recognized to be a cause of contagious mastitis. It can spread from cow to cow during the milking process and remain in a herd indefinitely due to a chronic carrier state. Economic losses due to elevated somatic cell counts (SCC), decreased milk production, higher treatment costs, and excessive discarded milk are commonplace in herds with cows infected with S. aureus.
The first signs of a herd problem with S. aureus may appear in the bulk tank. Bulk tank somatic cell counts (BTSCC) in excess of 400,000 could indicate a problem with contagious mastitis. Elevations in BTSCC are dependent on the number of cows and quarters infected. Very well managed herds can maintain relatively low BTSCC even though many cows are affected.
Greater than 80% of all S. aureus infections are subclinical. Usually there will be no fever and the only visible sign will be garget in the fore-milk. Many producers treat these quarters, leading to discarded milk and potential antibiotic residues. After treatment, these cases usually recur and the treatment/discarded milk cycle is repeated. As much as 88% of the losses incurred when treating cases of mastitis are due to dumped milk and decreased milk production.
Cows with one or more quarters infected with S. aureus tend to have elevated SCC. Keep in mind that one high score may not be indicative of a chronic infection. Cows with multiple SCC above 300,000 are most likely to be infected. Generally these cows can be detected with the California Mastitis Test (CMT), but monthly DHI data can be more revealing and requires less time and labor to obtain.
Milk cultures are the best method to determine if clinical and subclinical mastitis is due to S. aureus. All cows with repeated counts above 300,000 should be sampled. Once cows are selected, the CMT paddle can be used to determine which quarter(s) to culture.
A small (3-5 ml), sterile quarter sample is preferable to a voluminous contaminated composite. Contaminated milk samples are impossible to interpret and a waste of resources. Milk cultures should be immediately chilled to prevent overgrowth of environmental bacteria. If microbiologic procedures are to be delayed, the samples should be frozen. A veterinarian's assistance in obtaining high quality samples may be warranted.
Milking-time procedures can greatly influence the spread of S. aureus to uninfected cows. Contamination -- milkers' hands, common wash rags, and milking clusters -- with milk from infected cows is the primary means of transmission. Wearing latex gloves and using single service cloth towels or disposable paper towels will eliminate this method of transmission. Post-milking teat dipping with an approved, germicidal product will help reduce the number of viable organisms remaining on the teat skin after the milking unit is removed.
Good teat skin condition is vital to controlling S. aureus. This bacteria grows very well under scabs and on irritated teat skin. Higher incidence of S. aureus mastitis can be expected in winter months when teat skin becomes chapped. Irritating teat dips, excessive contamination by urine and feces, as well as improperly functioning milking machines can all cause teat end and teat skin damage. Selecting a teat dip with five to ten percent glycerine or some other skin conditioner will help tremendously.
Segregation of infected cows or using separate milking clusters on infected cows is a viable option for herds not choosing to cull. Smaller herds can designate one or two milking clusters as "Staph" units. These claws should be clearly marked and only used on infected cows. Another option is to milk the uninfected cows first and the "Staph" cows last. Larger herds can create a "Staph" milking string.
Heifers and new herd additions can be potential sources for introduction of S. aureus into uninfected herds. All new herd additions including heifers should be cultured within 30 days of entering the lactating herd. Animals testing positive should be immediately segregated. Milk culturing should be repeated to determine if the infections have become chronic.
The best way to live with S. aureus
in your herd is to identify infected cows and prevent the exposure of uninfected
cows to contaminated milk. Elimination of existing infections is best achieved
with appropriate lactational therapy, complete dry cow therapy and culling
chronically infected cows. New infections can be prevented by proper milking-time
procedures, post-milking teat dipping, maintaining teat skin condition,
and segregating uninfected cows from infected cows at milking time.
The start of a new year always brings unique challenges for the Illinois dairy industry. In order to face these challenges, we are often asked to make difficult decisions. Quality Milk Issues is a resource that can help you make the right decisions.
There are several other opportunities to obtain valuable decision-making information. Enclosed with this edition is a flyer announcing the Illinois Dairy Days. Topics cover many aspects of dairy production. The meetings will be held at twelve locations throughout Illinois. Come to the session nearest your home.
On January 25-28, 1998, the annual meeting of the National Mastitis Council, in conjunction with the International Dairy Housing Conference, will be held in St. Louis, MO. This is an excellent opportunity for everyone involved with the Illinois dairy industry to acquire the newest information on milk quality and mastitis, especially as it is related to dairy housing and environment.
On March 5-6, 1998, the Four-State Dairy Management Seminar titled "Focus on Forages: Grower Meets Producer" will be offered in the Wisconsin Dells. Find the time to attend at least one of these programs and become an informed decision maker.
Richard L. Wallace,
Editor
Dairy Extension Veterinarian
Midway through December, it appeared that
Illinois dairy producers had done an admirable job in monitoring job in
monitoring the use of antibiotics in their dairy cows. The number
of inhibitor violations in the second half of `199744 as of mid Decemberis
lower than the number in the same period in 1996, when there were 61 inhibitor
violations. This represents a decrease of over 25 percent!
Keep up the good work!
The Veterinary Extension office, in cooperation with the Laboratories of Veterinary Diagnostic Medicine at the University of Illinois College of Veterinary Medicine, is offering a new herd mastitis diagnostic service/ This new service will be funded by the Illinois Department of Public Health Alternative Drug Reside Penalty fund.
Herd mastitis sampling kits will be available to dairy producers and veterinarians. The insulated shipping boxes will contain 25 sterile milk sample vials, alcohol preps, and directions on how to aseptically collect milk from suspect cows. The focus of the program will be on identifying herd-specific mastitis pathogens. Then, good management practices can be developed to control mastitis and improve milk quality.
Details on how to obtain herd mastitis
kits will be presented at the Illinois Dairy Days.
Dawn E. Morin and Peter D. Constable
College of Veterinary Medicine
University of Illinois
[abstracted from Illinois Dairy Report,
1998]
Institution of teat dipping and dry cow antibiotic therapy has allowed many U.S. dairy farmers to control contagious mastitis caused by Strep ag and Staph aureus, and to maintain high quality milk with a low somatic cell count. Despite this, clinical mastitis remains a frequent problem, commonly affecting over one third of cows in a herd each year. The pathogens responsible for clinical mastitis in well-managed U.S. dairy herds are usually environmental bacteria, coliforms or fecal streptococci. Because these bacteria are abundant in the farm environment and on the teat skin, prevention of intramammary infection and clinical mastitis is difficult. When clinical mastitis occurs, the veterinarian or dairy producer must decide how to treat each cow.
Knowledge of the pathogens responsible for clinical mastitis facilitates treatment and management decisions. Environmental streptococcal bacteria are more likely to respond to antibiotics currently labelled for mastitis treatment than coliform bacteria. Therefore, selective antibiotic treatment of only those cases of clinical mastitis caused by fecal streptococci would seem economically prudent. Unfortunately, there are no cow-side tests available in the U.S. that accurately and rapidly determine the pathogen responsible for clinical mastitis. As an alternative to culturing the milk, many veterinarians and producers use clinical signs or historical information to predict what the pathogen might be. However, published studies indicate that the accuracy of clinical prediction is relatively poor.
It is a common conception that coliform mastitis is more severe than streptococcal or staphylococcal mastitis, however, most cases of coliform mastitis are actually mild. The objectives of this study were to determine the ability of clinical signs and historical information to distinguish between cows with coliform or fecal streptococcal mastitis, and to investigate the cause of clinical mastitis when no bacteria were isolated from the milk.
The trial was conducted over a 2-year period at the University of Illinois Dairy Research Farm. All cows that developed clinical mastitis within 14 days of were examined. The parameters recorded included season of the year, lactation number of the cow, days since parturition, rectal temperature, heart rate, rumen contraction rate, degree of dehydration, size, color, consistency, temperature, painfulness and edema of the udder, presence of visible or palpable teat lesions, color, viscosity, and consistency of the milk, and overall severity of disease, as well as milk production, somatic cell count, milk fat percent, milk protein percent and milk fat:protein ratio at the preceding DHIA test. Milk was collected for bacteriological culture before any treatments were administered.
Only 2 of the 24 parameters differed between cows with coliform or streptococcal mastitis: rumen contraction rate was lower and milk protein percentage higher in cows with Gram negative infections. However, small numerical differences in rumen contraction rates and large standard deviations associated with milk protein percentages for cows in the 2 groups indicate that these parameters have limited diagnostic usefulness when applied to an individual cow. Using logistic regression, several parameters were identified as significant predictors of Gram negative mastitis: mastitis in summer, watery milk, rumen contractions < 3/2 min, milk protein percent > 3.5 and high lactation number. However, when used singularly or combined into models, the predictive values of these parameters in a typical herd (with 50% of clinical mastitis caused by coliforms) would be < 75%.
Episodes of clinical mastitis with no bacteria isolated from the milk were significantly different from those with Gram positive bacteria isolated, and similar to, but milder than, those with Gram negative bacteria isolated, suggesting that they were the result of low-grade or transient coliform bacterial infections. This is consistent with experimental and clinical evidence that coliform bacteria are often rapidly reduced to low numbers or eliminated from the gland, while clinical signs of mastitis persist.
Cows with coliform mastitis cannot be accurately
distinguished from cows with streptococcal or staphylococcal mastitis on
the basis of clinical signs. Although cows with streptococcal or staphylococcal
mastitis are more likely than cows with coliform mastitis to respond to
antibiotic therapy, using clinical signs to select cows for antibiotic
therapy will result in misclassification of many cows.
Anne Saeman, National Mastitis Council
[abstracted from Udder Topics,
Oct/Nov 1997]
During the May 1997 National Conference on Interstate Milk Shipments (NCIMS) the voting delegates accepted a proposal to modify the provision in the Pasteurized Milk Ordinance (PMO) which deals with premilking udder and teat with a sanitizing solution prior to milking would be changed to a recommendation.
To aid in their decision, FDA conducted a technical review on the effects of udder preparation on milk quality and udder health. In summarizing the review, FDA stated "Despite the wealth of available studies on milking practices and udder health, there is a scarcity of comparative literature on the effects of those udder preparation methods which do and do not include treating teats with sanitizing solutions prior to milking." FDA went on to say that "Despite this scarcity, it is clear that a portion of the information available supports the current requirement that teats be sanitized prior to milking and a portion of the information supports the concept that there can be acceptable alternatives to the current requirement." FDA said they were "prepared to accept both premises equally."
Based on a literature review, FDA has accepted an alternative to the requirement to treat teats with a sanitizing solution prior to milking. "Sanitizing of the teats shall not be required if the udder is dry and the teats have been thoroughly cleaned (not dry wiped) and dried (manually wiped dry) prior to milking. The determination of what constitutes a dry udder and cleaned and dried teats shall be made by the regulatory agency." FDA also noted that "additional alternative udder preparation methods may also be used once they have been evaluated by FDA and found acceptable."
According to FDA, well controlled research studies could likely identify additional acceptable alternative udder preparation methods. The studies need to focus on comparing the effects of udder preparation methods, under various climatic and management conditions, with and without treating teats with sanitizing solution prior to milking. FDA will evaluate such studies upon submission to determine whether they are acceptable alternatives. FDA encouraged individuals interested in conducting such research to consult with the agency to review protocols for the study.
NCIMS memoranda, model documents, such
as the PMO, and other information regarding the NICMS program are available
through the FDA Prime Connection, an on-line resource library of information
on retail food protection, milk safety and seafood safety. The Prime
Connection can be accessed from the FDA Center for Food Safety and Applied
Nutrition (CFSAN) web page at <http://vm.cfsan.fda.gov/>.
Quality Milk Issues: A Resource for the Illinois Dairy Industry is intended for all individuals participating in the production, processing and marketing of milk and dairy products in the state of Illinois. This newsletter will contain educational and informational items. Everyone involved in the Illinois dairy industry is encouraged to read the articles and contribute items for future issues. The major thrust of this bulletin is to enhance the production of quality milk in the state of Illinois. Contact me by E-mail or at the above address if you have information to contribute.
If you are a dairy producer, be sure that all of your employees have access to this newsletter. If you are the farm owner but do not manage the day-to-day operations, pass this bulletin on to your herd manager or family members. Milk processors and feed companies should make certain that their field representatives obtain a copy of this newsletter. Veterinary practitioners are welcome to distribute the information to all associates and clients.
As we share and exchange more information and ideas, we increase the opportunity to produce high quality milk. So be sure to "pass the word" including this newsletter.
Richard L. Wallace, Editor
Dairy Extension Veterinarian
E-mail: rwallace@cvm.uiuc.edu
Compared with the first half of 1996, the inhibitor violations in the first half of 1997 are down nearly nine percent. There were 68 inhibitor violations in the first half of 1996 as compared to only 62 in the first half of 1997.
The Peoria and Marion regions led the way
with the largest decreases, 57 and 33 percent respectively. Congratulations
are in order to the Illinois milk producers who continue to strive to produce
the safest milk possible.
Quality of milk can be affected during the production, processing, or distribution phases. Milk quality cannot be improved once it leaves the farm. In order to maintain high quality milk supplies and consumer confidence, proper standards must be sustained until dairy products are utilized.
Proper cooling of milk is of great importance. Excellent sanitation procedures are of questionable value if milk is not cooled properly. Milk must be cooled to 45 F (7 C) or less within two hours after milking and maintained at that temperature until processed. On subsequent milkings, the blend temperature may not exceed 50 F (10 C).
Inadequate cooling can contribute to elevated
bacteria counts. Production of high quality milk helps ensure that a valuable
nutrient source will be available to consumers. This availability, in part,
depends on adequate cooling of raw milk.
Dick Wallace, Dairy Extension Veterinarian
University of Illinois at Urbana, Champaign
Several Pseudomonas aeruginosa mastitis outbreaks have been reported to the Veterinary Extension office over the past year. If you've ever experienced wide swings in bulk tank bacteria and/or somatic cell counts as well as non-responsive, recurring cases of clinical mastitis, you too may have experienced problems with Pseudomonas. Commonly, multiple cows are affected simultaneously. Cows can have high fevers and swollen quarters, or they may just be slightly off feed and have abnormal milk. Subclinical cases of Pseudomonas mastitis have been reported along with explosive herd outbreaks of clinical mastitis.
These organisms can be found in soil, animal feces, barnyards and water supplies. Trouble begins when poorly cleaned milking equipment or water supply lines become contaminated. Pseudomonas can colonize inside drop hoses even when iodine or other disinfectants are added to the water. Less than recommended concentrations of iodine may cause the organisms to produce a slime layer for protection. Low levels of Pseudomonas can survive in the farm water supply. Once the organism reaches the pre-heater, it finds favorable conditions for growth and can seed the entire water system.
Contaminated antibiotic preparations intended for intramammary infusion have also been implicated in outbreaks of Pseudomonas mastitis. Always use sterile procedures to administer antibiotics. Scrub the teat end thoroughly with an alcohol pad prior to infusion. Make certain the tip of the antibiotic tube does not touch anything but the cow's teat canal.
If a Pseudomonas problem is suspected, management of herd infections must include efforts to identify the source. Cultures are often necessary to determine if Pseudomonas is the culprit. Cows with clinical mastitis, chronic non-responsive mastitis and/or high somatic cell counts should be sampled. Water from parlor drop-hoses as well as teat cups and teat dippers should be sampled. Do not sample drop hoses immediately after milking. Allow the water in the hoses to settle and stand a while before culturing.
Treating cows with clinical mastitis due to Pseudomonas has been unrewarding. Cows will appear to clear up, only to relapse or become reinfected a short time later. Some infections will resolve spontaneously, while many infected cows will eventually be culled.
Several steps are required to cleanse water
systems contaminated or colonized with Pseudomonas. If a well is
the water source for the parlor and milking facilities, it can be chlorinated.
Flushing the entire system with water at or above 160 F will help decontaminate
colonized water lines. Periodically flushing parlor drop hoses with
160 F water will help prevent the organism from becoming reestablished.
The Illinois Dairy Field Representative and Sanitarian Association and the Illinois Cooperative Extension Service have developed a laminated barn card depicting ten common reasons antibiotic contamination occurs in bulk tank milk. Production of the barn cards was supported by the Illinois Department of Public Health Alternative Drug Residue Penalty Fund.
The front of the residue prevention barn card lists the ten most common reasons for antibiotic residues as identified by the field representative and sanitarian group. The back of the card lists intervention strategies to reduce the residue potential. The cards have been laminated so dairy producers can display them prominently in their milk houses. Owners and employees can easily refer to the card whenever a question arises.
Many of the barn cards will be distributed
by dairy plant field representatives. Others will be enclosed with this
newsletter. All dairy producers are encouraged to review the items with
individuals responsible for treating and milking their cows. Any questions
can be directed to the local veterinary practitioner or the University
of Illinois, Veterinary Extension at 217-333-2907.
|
|
| Milk from a treated cow was accidently routed into the pipeline. |
| Antibiotic residues remained in the milk of a recently fresh cow (that had previously received dry cow therapy) or a treated cow longer than the presumed withholding time. |
| Equipment used to milk treated cows was handled carelessly; for example, vacuum from the milk pipeline was used operate dump-milk buckets. |
| Lactating cows were purchased and the new owner was unaware of recent antibiotic treatments prior to sale. |
| The same milking unit was used to milk an antibiotic-treated cow before milking untreated cows. The milking unit was not cleaned and sanitized between uses. |
| An antibiotic-treated dry cow was unintentionally milked. |
| All antibiotic-treated cows were milked last, but the milk line was not diverted from the bulk tank. |
| Cows drank from a medicated footbath. |
| Medicated feed was accidently mixed into the lactating-cow feed. |
| One quarter of a cow was treated for mastitis and withheld from the bulk tank. However, milk from the other three quarters was not withheld and was permitted to enter the pipeline. |
FDA, Center for Veterinary Medicine
Edited from February 12, 1997, CVM
news release
FDA has received reports that products containing colloidal silver are being promoted for use in the treatment of mastitis and other serious disease conditions of dairy cattle. The FDA's Center for Veterinary Medicine has received reports that colloidal silver products have been found on some dairy farms. Also, recent articles in some farm newspapers and journals promote the use of colloidal silver in treating mastitis and claim that no milk discard is needed.
FDA is not aware of any substantial scientific evidence that supports the safe and effective use of colloidal silver ingredients or silver salts for any animal disease condition. Also, in the Oct. 15, 1996, Federal Register, FDA proposed to establish that all over-the-counter human drug products containing colloidal silver ingredients or silver salts for internal or external use are not generally recognized as safe and effective and are misbranded.
Use of colloidal silver ingredients in food-producing animals constitutes a potentially serious public health concern because of the possibility of residues in milk or meat. According to several scientific publications mentioned in the Oct. 15, 1996, Federal Register proposal, the human consumption of silver may result in argyria a permanent ashen-gray or blue discoloration of the skin, conjunctiva, and internal organs.
In addition to the possible human health concerns, use of these products to treat a serious illness in animals could potentially endanger the health of the animal by delaying timely, appropriate treatment.
Colloidal silver-containing products have not been approved by FDA for use in any animal species. Promoting the use of colloidal silver for treating animal diseases causes such products to be misbranded veterinary drugs under the Federal Food, Drug, and Cosmetic Act. Labeling colloidal silver products to treat animals causes such products to be new animal drugs which are adulterated in the Act.
FDA has taken action against colloidal
silver products, and is continuing to investigate the promotion and use
of colloidal silver products in dairy and other animals. If necessary,
FDA will take further appropriate regulatory action.
This is the first edition of Quality Milk Issues: A Resource for the Illinois Dairy Industry. It will be produced and distributed twice a year by the Office of Continuing Education-Public Service, Extension at the College of Veterinary Medicine, University of Illinois. The current circulation encompasses the dairy industry in the State of Illinois, including dairy producers, dairy processors, milk sanitarians, milk haulers, veterinarians and others involved with dairy.
Enhancing the production of quality milk will be the major thrust of this bulletin. Issues to be discussed will include reasonable and responsible antibiotic use, residue avoidance, reducing bacterial counts and lowering somatic cell counts. Appropriate notices from the Food and Drug Administration (FDA) and Centers for Veterinary Medicine (CVM) will be condensed and incorporated. Other topics involving good management practices as they relate to the production of high quality milk will be explored. Suggestions for topics can be relayed to any of the University of Illinois, Cooperative Extension Service personnel listed later in this issue.
I hope this becomes a valuable resource for you. The ultimate goal for each one of us involved with the Illinois dairy industry is producing milk of the highest quality.
Richard L. Wallace, Editor
Dairy Extension Veterinarian
Marlena Bordson
Dairy Program Manager
Division of Food, Drugs and Dairies
Illinois Department of Public Health
This fund was established by Public Act 88-0600, sponsored by State Representative I. Ronald Lawfer, a northern Illinois dairy farmer. This Act amended the Illinois Grade A Milk and Milk Products Act and the Illinois Food, Drug and Cosmetic Act to provide for an alternate equivalent monetary penalty in lieu of 48- or 96-hour permit suspensions for antibiotic residue violations.
Appendix N, Drug Residue Monitoring and Farm Surveillance, of the Pasteurized Milk Ordinance was adopted at the 1991 National Conference of Interstate Milk Shippers. This provision required that a penalty for drug residue violations, 48- or 96- hour permit suspension or equivalent penalty be administered by the state regulatory agency. Until the passage of Public Act 88-0600, the Department did not have the authority to establish an equivalent penalty.
Representative Lawfer, in cooperation with
the Illinois Dept. of Public Health, held a series of public hearings in
early 1995 to develop the rules necessary to implement this law. These
hearings were attended by dairy producers, dairy field representatives,
dairy plant operators, Department staff, and State legislators from the
surrounding areas. Comments from these hearings were used in drafting the
final rules. The rules became effective in August 1995. Included
in the Act and rules was a provision that the monies collected be deposited
in a special fund dedicated to drug residue prevention efforts, producer
education and providing information in the prevention of drug residues.
Michael F. Hutjens
Extension Dairy Specialist
University of Illinois, Urbana
Years ago, it was thought that feeding too much corn caused garget milk (clots and flakes) and too much soybean meal led to hard quarters. Mastitis research then investigated why these cows developed abnormal milk and found that it was not directly related to feeding.
Nevertheless feeding does have an impact on mastitis. Proper nutrition can decrease new mammary infection rates by improving the cow's immunity. The immune system of the cow combats disease by antibody/antigen reactions and/or the ability of white blood cells (somatic cells) to kill bacteria. Key micronutrients (added in relatively small amounts per day) that can improve immune response are listed below.
* Selenium
* Zinc
* Copper
* Vitamin A
* Vitamin E
Ohio State University workers have shown that proper amounts of vitamin E and selenium during lactation and dry period can result in a 42 percent reduction in mammary infections at calving, 32 percent reduction in clinical mastitis, 45 percent shorter duration in infections, and 68 percent reduction in high somatic cell cows. University of Kentucky workers have demonstrated the importance of copper in reducing the severity and duration of mastitis at calving. Supplemental zinc has significantly reduced somatic cell counts. Vitamin A is important in maintaining the integrity of skin surfaces and linings.
The level of these important micronutrients that should be included in the ration as supplemental inorganic minerals is indicated in Table 1. Research with chelated or complex trace minerals is minimal, but if used, add an additional 25 percent chelated to the amounts listed in Table 1. This is especially important in close-up dry-cow and fresh-cow diets. These groups of cows are under the greatest challenge from infectious agents.
Table 1. Suggested amounts of trace minerals
to add to dairy diets.
(mg=milligrams; IU = international units).
| Nutrient | Amount/cow/day |
| Selenium (Se) | 6 mg |
| Copper (Cu) | 200-250 mg |
| Zinc (Zn) | 900-1200 mg |
| Vitamin A | 100,000-150,000 IU |
| Vitamin E (milk cows) | 400-800 IU |
| Vitamin E (dry cows) | 1000 IU |
Animal Sciences 492/299 will be offered at five locations (Quincy, Pontiac, Rockford Breese, and Urbana) by long distance learning linkage. The class is held Tuesday nights starting on Jan. 28, 1997, for ten weeks. Two classes will be held on campus allowing for on-farm evaluation techniques and computer applications on nutrition.
Instructors include:
Mike Hutjens, Dick Wallace, Dave Fischer, Jimmy Clark, and Jim Drackley.
Contact Mike
Hutjens for more details and information. (Voice) 217-333-2928, (Fax)
217-333-7088.
Producers in counties in south central
Illinois are experiencing some problems with aflatoxin in new corn from
drought-stressed fields. Aflatoxin contaminated milk has been rejected
at area dairy plants. Producers shipping milk with higher than allowable
concentrations have been identified. Notices are being sent to producers
in the counties which have been affected and also to surrounding counties.
State regulations establish an action level of 0.5 ppb for aflatoxin
in milk. Questions about aflatoxin, resources for testing and information
on feed problems may be directed to the Cooperative Extension Service personnel
listed in this issue.
Oxytetracycline is an antibiotic routinely used in an extra-label manner for intrauterine therapy. Research supporting the efficacy of intrauterine antibiotics is minimal, yet the practice is common. A study was performed to establish the duration of oxytetracycline residues in milk from cows with retained fetal membranes given the antimicrobial via intrauterine infusion. The study also investigated whether the number of infusions or the presence of fever affected the duration of residues.
Fifty-four Holstein cows with retained fetal membranes on a single 1,400-cow commercial dairy were used in this study. Cows were treated once a day with 5 g of oxytetracycline by intrauterine infusion for at least 2 days, or until the membranes were expelled. Cows that became clinically ill (fever and off-feed) were also given procaine penicillin G at 20,000 IU/kg (9,000 IU/lb) of body weight, IM daily for 2 to 4 days. Milk samples were collected at 24-hour intervals during treatment, and at 12-hour intervals after the last treatment. All samples were frozen and submitted every 2 weeks for high performance liquid chromatography (HPLC) analysis for oxytetracycline.
Oxytetracycline was detected in milk of all cows during treatment, at a maximum concentration ranging from 47 to 1,805 µg/kg (ppb). Duration of oxytetracycline residues after the last infusion ranged from zero to 144 hours (6 days). Neither the number of infusions received nor development of rectal temperature greater than 39.7 C (103.5 F) affected the maximum concentration or the duration of oxytetracycline residues in milk.
Milk obtained from cows that are treated
for retained fetal membranes by intrauterine infusion of oxytetracycline
may contain the drug for variable lengths of time. Milk should be discarded
to avoid illegal residues. Contact your veterinarian for appropriate withholding
times.
Dipyrone is an unapproved prescription product which has been permitted to be sold under regulatory discretion. The labeled use of dipyrone is as an injectable analgesic/antipyretic for horses, dogs and cats. The label specifically prohibits the use of this product in food-producing animals. The scientific literature lacks adequate data to show that dipyrone is safe and effective in animals. There is no information on pharmacokinetics, and no regulatory method for assay of dipyrone residue or its metabolites in milk or meat.
On April 10, 1996, the chief of the Milk Safety Branch released the following statement (in part): "Dipyrone is not approved for use in animals. Dairy farmers, veterinarians and consultants should be aware that the use of dipyrone is illegal drug use. Drug manufacturers/distributors have been given until September 1996 to remove this drug from distribution/sales channels. If dipyrone is observed on a dairy farm during a rating or check rating inspection after March 1, 1997, it would be in violation of Item 16r(i) of the Pasteurized Milk Ordinance."
This would be a major deduction on a federal
inspection of a dairy farm.
Mike Hutjens, Extension Specialist, 1207 W Gregory Ave, Urbana IL 61802, 217-333-2928 Fax: 217-333-7088
Dick Wallace, Extension Veterinarian, 2001 S Lincoln Ave, Urbana IL 61802, 217-333-2097 Fax: 217-244-2988
Dave Fischer, Extension Educator, 200 Univ Park Dr, Edwardsville IL 62025, 618-692-9434 Fax: 618-692-9808
Jim Endress, Extension Educator, 773 W Lincoln, Freeport IL 61032, 815-233-3214 Fax: 815-233-4511
Wes Winter, Unit Educator, Stephenson Co., 2998 W Pearl City Rd, Freeport IL 61032, 815-235-4125 Fax: 815-232-9006
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