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Services available through the TDA laboratory…  

1. Milk Quality Lab (Bacterial and mycoplasma cultures, SCC, SPC, PI, LPC, etc.)
2. Milk screening for antibiotics
3. Fecal sample culture (includes fecal float for parasite egg counts if requested)
4. Fecal culture for Johne’s to be offered beginning 4th quarter 2007
5. Other culturing also provided (tissue, bedding, towels, water, etc.)
6. Total Blood Protein reports (estimate of IgG in calves)
7. Serum NEFA levels for assessment of energy balance in transition cows.
8. Antimicrobial susceptibility testing.
9. ELISA serum testing for Johne’s, BVD , BLV and Pregnancy test for cattle
10. We have now added Sommatic Cell Testing testing to our laboratory. You can have the Somatic Cell Count of a tank, pen or individual cow within a couple of hours of dropping off the sample. Please email or call for any questions!

 

Getting Samples to the Lab...

Samples may be mailed, delivered or couriered to our laboratory. Certain samples may have special requirements (ie: for example its best to ship milk samples frozen on ice) so if you are not certain please call us at 970.351.8102 or send an email to us at TDA Lab.

Shipping Address...

• The Dairy Authority
• Attn: Lab
• 8215 W. 20th St., Unit A
• Greeley, CO 80634

Courier Service...

The Dairy Authority also provides a courier service to local clients. We have a route that runs through most of Northern Colorado. Call us to inquire when our couier service comes through your area.

For any questions please feel free to contact us at 970.351.8102 or email us at TDA Lab.

A question may also be submitted through our online form by clicking here.

Milk Quality Lab

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Cultures

Milk samples are cultured for all common mastitis pathogens however the uncommon pathogens are also identified and reported out as well to aid in the treatment and prognostication of the mastitis event.

1. Identification of all bacteria cultures reported to the genus level (i.e.: E.coli, Bacillus spp., Serratia spp., etc.)
2. All contagious bacteria specifically reported (ie: Strep ag, Staph aureus and Mycoplasma spp.)
3. Quantitative counts conducted and reported on ALL positive bacteria cultures to aid in treatment and prognosis of the cow.
4. Special procedures taken on tank/string samples used for monitoring to count the number of staphs, streps and coliform organisms.
5. Mycoplasma culturing available
6. Online access available for milk sample results (password required).
7. Results can be downloaded in some dairy management software packages (ie: DairyComp 305)

Milk Screening for Antibiotics

1. Routine testing done for antibiotics in milk
2. Individual and bulk milk testing available
3. After hour testing available upon request (Call 970.351.8102)

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Fecal Culturing

1. Aerobic fecal cultures performed (Salmonella, E.coli, etc.)
2. Anaerobic cultures performed (Clostridial cultures)
3. Fecal floats to identify parasites and other parasitisms.

Other Cultures

1. General culturing performed on all substrates
2. Tissue, water, bedding and towel culturing readily available

Antimicrobial Susceptibility Testing

1. The standard panel of 8 antibiotics tested using the Kirby-Bauer method are: Amoxicillin/Clavulanic Acid, Ampicillin, Cephalothin, Erythromycin, Novobiocin, Penicillin, Tetracycline, Trimethoprim/Sulfamethoxazole.
2. Up to 3 of the above antibiotics can be replaced by one of the following antibiotic sensitivity test disks in stock: Amikacin, Cefazolin, Sulfisoxazole .
3. Disks for susceptibility evaluation of 33 other antimicrobials can be obtained by special request. Please contact The Dairy Authority Laboratory to discuss special requests.

Total Blood Protein

1. Total Blood Proteins (TBP) are used to evaluate colostrum management in calves.
2. Total Blood Proteins estimate the level of IgG provided to the calf.
3. TBP are much less expensive to run than an actual IgG test.
4. Serum required 24-48 hours after last colostrum feeding

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NEFA (Non Esterified Fatta Acid) Testing

1. Evaluation of transition cow management is now possible with NEFA testing
2. Level of NEFA indicates energy status of cows and help identify the level of fat mobilization in dairy cattle.
3. Excessive NEFAs may lead to a multitude of post partum (fresh) cow problems.

ELISA Tests

1. BVD antigen capture ELISA

 Bovine Viral Diarrhea Virus is an RNA virus belonging to the genus Pestivirus. It is endemic in cattle populations in the United States and other countries around the world. BVDV can infect susceptible cattle of all ages, but is especially costly when it infects pregnant females. Fetal infection between 60-120 days gestation may result in what is known as a Persistently Infected (PI) calf. Persistently infected cattle are lifetime carriers of BVDV and are the means of propagation of BVD in cattle populations. BVD control programs are geared toward identifying PI animals and promptly removing them (permanently) from the population.

 Test specifics- BVD

The antigen capture ELISA test is an accurate, rapid method of identifying cattle persistently infected with BVDV. The test can be performed on either serum or skin biopsy (ear notch) samples stored in phosphate buffered saline solution (PBS). Once started, the test takes 4 hours to complete.

Serum from calves should not be submitted for testing unless the sample was collected prior to feeding colostrum or the calf is >3 months of age. This is due to maternal antibody interference, which can increase the risk of false negative results.

 Skin biopsy samples can be submitted from cattle of any age, including young calves < 3 months of age.

Although rare, there is a slight chance of the test detecting a transient infection. Therefore animals that test positive are often retested 3 weeks later for verification of PI status.

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Sample collection and handling for BVD

 Serum samples should be collected in red top serum tubes and stored chilled prior to submission to the lab. If blood samples are to be stored more than a few days prior to submission, serum should be removed from the clot. Separated serum samples can be frozen and stored for longer periods of time if necessary.

Skin biopsy samples should be collected into individual tubes and the tubes labeled with date, client name and ID. Samples should be frozen prior to shipment.

Ship so that samples are received in 1-2 days and always ship samples on ice (cold packs best).

 Keep in mind that testing is only one component of a complete BVD control program. Proper vaccination, biosecurity and biocontainment are other important issues to address when designing a comprehensive plan to deal with BVDV. Our staff would be glad to address any questions you may have regarding BVD control programs.

2. Johne’s ELISA testing

Johne’s disease is a chronic, debilitating disease in cattle characterized by widespread enteritis resulting in diarrhea and weight loss. The disease is the result of infection with the bacteria Mycobacterium avium subsp. paratuberculosis. Bacteria are shed in high numbers in the feces of infected cattle and also through the milk and colostrum. Once infected, cattle are considered to be shedders for life. Increased shedding of bacteria by cattle increases during periods of stress such as during calving or any type of illness. Since the infection is spread by fecal ingestion of the bacteria and newborn and young calves are the most susceptible, control programs are geared toward decreasing the amount of exposure of susceptible calves to M.paratuberculosis. Identification of cows that are possible carriers and segregating them at calving is one strategy to attempt to decrease spread of Johne’s within a herd.

Fecal culture for Johne’s is considered the “gold standard” for diagnosis, however, the turn around time for results is between 12-16 weeks and the culture can be quite costly. On the other hand, ELISA testing is a fast, cost effective means of detecting the presence of Johne’s antibodies in blood. It is best used as a screening tool for groups (herds) of animals and not for making decisions on individual animals within a given herd.

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Test specifics- Johne’s

The test we use is the ELISA test developed by Biocor and currently marketed by Pfizer Animal Health. Results are reported as follows: Negative, inconclusive and positive. We calculate a score based on the optical density of the test and this score is reported with all results. The higher the score, the more strongly positive the result is. A sheet describing interpretation in comparison with the Idexx ELISA is sent with each set of results. The assay takes 2 hours to complete once it has been started.

Sample handling- Johne’s

Blood samples should be collected in red top clot tubes. Samples can be stored for 1-3 days in the refrigerator. If samples are to be stored for 3+ days prior to testing, then serum should be separated from the clot. Ship samples on ice for receiving in 1-2 days.

ELISA testing, like any other diagnostic test, is only part of a comprehensive Johne’s control program. Each farm has different goals and needs for Johne’s control and should have a custom designed program for their specific enterprise. We would be glad to discuss any Johne’s control issues or questions you may have.

3. Biopryn pregnancy test

Biopryn is an acronym for a ruminant-specific pregnancy test developed by Dr. Garth Sasser at the University of Idaho. The test specifically looks for the level of bovine pregnancy protein B in serum. The ELISA reader calculates the optical density of the individual cow and compares this value with known controls including both open and pregnant cows. Based on this comparison, the results are reported as open, pregnant and pregnant-recheck. These reports can be transferred electronically into on-farm software if the client so chooses. The Biopryn test requires an overnight incubation period and results are reported approximately 24 hours after the test is first set up.

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Animal selection and sample handling- Biopryn

Previously pregnant cows must be at least 90 days postpartum in order for any residual protein B from the previous gestation to be gone. Cows also need to be a minimum of 30 days post insemination. Virgin heifers should be at least 30 days post breeding in order to get an accurate test result. This test only tells you if the cow is pregnant or open. Gestation cannot be staged by this particular assay. Blood should be collected in a clot tube and stored under refrigeration until submission for testing. Pregnancy protein B is quite stable and there seem to be no untoward effects of serum sitting on the clot. Also, it is not critical that samples be refrigerated for shipment; however, it is a good idea to have them refrigerated prior to shipment. Samples should be shipped for receiving in 1-2 days.

The Dairy Authority has done side by side comparison testing between the Biopryn test and rectal palpation by experienced DVM palpators. The results of the test have been very comparable with palpation and we are in the process of calculating the sensitivity and specificity of this assay. The test has worked extremely well in virgin heifers and is becoming a preferred means of pregnancy diagnosis for AI bred heifers. In dairy herds, the test can provide the opportunity for more frequent (weekly) checks in some herds where it is difficult for a palpator to get there at the same frequency. This allows for more rapid diagnosis of open cows and an opportunity for earlier re-enrollment into synchronization programs. In addition, the non-invasive nature of the test reduces the chances of embryo damage during early gestational palpation. We would be glad to discuss this test in greater detail with anyone interested in finding out more about it.

4. Bovine Leukemia Virus (BLV)

Bovine Leukemia Virus is the causative agent of bovine leukosis, a highly fatal form of cancer in cattle. Clinical signs are often absent until the extremely late stages of the disease. Late stage leucosis is characterized by lymphadenopathy(enlarged lymph nodes) in various regions of the body, commonly in the subiliac(pelvic) region. These tumors are often found by rectal exam. Tumors can also often be found in the abomasum, uterus and the spine.

Once infected with BLV virus, cattle are lifetime carriers and shedders of the virus. Virus is spread through animal to animal contact via blood, milk/colostrum and in-utero from dam to offspring. Also, an important means of transmission is though blood contamination of needles and surgical instruments as well as rectal sleeves used in multiple cows.

The BLV ELISA test is used to detect the presence of Anti-BLV antibodies in serum. A positive result indicates exposure to the virus. All positive animals will not necessarily develop tumors and may not be chronic carriers. Test results should be discussed with a veterinarian before any decision is made to sell or retain individuals or groups of cows based on test-positive status. There are numerous components of a BLV control program and veterinary consultation is recommended before any BLV control program is initiated.

 

You may request more information on any of our lab services from the "Contact" page.

 

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