Amino Acid Laboratory

Amino Acid Laboratory

The Amino Acid Laboratory is in the Department of Molecular Biosciences of the School of Veterinary Medicine and Dr. Jennifer Larsen is the Academic Director.  It offers analyses for research and diagnostic purposes.  It is a nonprofit laboratory; the fee structure is approved by the University.

Sample Type for Disease Diagnosis:

• Cardiac Disease (Dilated Cardiomyopathy, with or without congestive heart failure): Plasma or/and Whole Blood
• Hepatic Disease (Hepatocutaneous Syndrome, Hepatitis): Plasma
• Urolithiasis: Urine
• Research: Project-dependent sample types

Services and Current Rates

Please use the current Submission Form for all tests.  Please complete the submission form as thoroughly as possible (include the sample type you are sending, the test requested, and the billing party’s complete mailing address), print it, and include it in your shipment.

RATES, EFFECTIVE JANUARY 1, 2019 (increases are expected in late 2024).

Complete Plasma Amino Acid Analysis or Rates*                                     

*Important Billing Information:

For patient sample submissions: Please await the invoice to be emailed to your clinic (from no-reply@mail.ppms.info); payment via wire transfer, check, or credit card. Do not send a check with your sample. We can also bill the pet owner directly; please provide the needed information on the submission form.

For research submissions: Please provide your UC Account # (non-federal funds only).

Sample Preparation

Plasma (for complete amino acid analysis or taurine)

PLEASE NOTE: we do NOT spin down samples for plasma in our laboratory, if a plasma test is desired, you must send us the sample as plasma

• If using a lithium-heparin (green top) tube:  Draw 2 ml (or more) of blood into the green top tube (not outdated).  Invert 5 times to mix.  Immediately centrifuge the blood and take off the plasma using a Pasteur pipette or eye dropper.  Take care not to disturb the buffy coat (white blood cells contain a lot of taurine).  Put the heparinized plasma into a no-additives tube (i.e.:  white top, red top, but NOT a serum separator). Heparinized plasma should be straw colored and not hemolyzed.
   
• If no green top is available:  Add 2-3 drops of heparin in a syringe.  Draw blood into the syringe followed by approximately 1cc of air to mix the blood and heparin thoroughly (invert approximately 5 times).  Remove the needle and place the blood in a no additives tube (i.e.:  white top, red top, but NOT a serum separator).  Immediately centrifuge the blood and take off the plasma using a Pasteur pipette or eye dropper.  Take care not to disturb the buffy coat (white blood cells contain a lot of taurine).  Put the heparinized plasma into a no-additives tube (i.e.:  white top, red top, but NOT a serum separator). Heparinized plasma should be straw colored and not hemolyzed.
   

Whole blood (for taurine only)

• If using a lithium-heparin (green top) tube:  Draw 2 ml (or more) of blood into the green top tube (not outdated).  Invert 5 times to mix.  No need to spin.
• If no green top is available:  Add 2-3 drops of heparin in a syringe.  Draw blood into the syringe followed by approximately 1cc of air to mix the blood and heparin thoroughly (invert approximately 5 times).  Remove the needle and place the blood in a no additives tube (i.e.:  white top, red top, but NOT a serum separator).  No need to spin.

Urine (for complete amino acid analysis or taurine)

• Please send at least 1 ml in a urine tube (white top) or other “no additives” tube.

AGAIN, DO NOT USE A SEPARATOR TUBE.

Shipping Samples:

If shipping the same day:  plasma, whole blood or urine samples can be held in the refrigerator until shipped.  Please ship on ice.

If holding the sample 24 hours or longer:  plasma, whole blood, or urine samples should be frozen (-18ºC or 0ºF) until shipped.  Please ship on ice.

Please ship samples overnight.  You are able to use the carrier of your choice (FedEx, UPS, USPS).  We do not receive samples on weekends or University Holidays, so please only ship Monday-Wednesday for USPS or Monday-Thurs for FedEx and UPS.

Our Mailing Address:

Amino Acid Laboratory, 1020 Vet Med 3B
University of California, Davis
1089 Veterinary Medicine Drive
1020 Vet Med 3B
Davis, CA 95616

Shipping Tips:

• Glass tubes will easily break in transit, please pad them appropriately.
• Tube lids can come off in transit, please fasten them securely.
• Submission forms are easily soaked due to leaky/wet ice packs, please fully enclose in a plastic bag

Turn Around Time and Results

Complete amino acid analysis results (for plasma and urine) will be available within 7 working days. Sample numbers larger than 50 may require additional time.

Taurine analysis results (plasma, whole blood, urine) will be available within 5 working days.

Samples needing hydrolysis or digestion (food, body tissue, or other solid samples) will require 3 additional days for any test.

We Process Samples using the Following Methods 

Complete amino acids in physiological fluid samples:  add 6% Sulfosalicylic Acid (SSA) (1:1) to sample for deproteinization, centrifuge the mixture at 14000 rm for 25 minutes, filter the supernatant through 0.45 mm syringe drive PTFE filter, adjust pH to 2.2, load 50 ml on Biochrom 30 amino acid analyzer.

Complete amino acids in solid samples: hydrolyze 5 mg sample using 5 ml of 6 Nmol HCl in sealed ampoule (110ºC, 24 hrs.), dry the sample with nitrogen gas, dissolve it again in loading buffer, filter the hydrolyte and load 50 ml on Biochrom 30 amino acid analyzer without dilution.

Free amino acids in tissues or feed: add 3% SSA solution to homogenized sample (10:1 V:W), let stand overnight at room temperature, centrifuge and filter the supernatant (0.45mm), adjust pH to 2.2 and load 50 ml on Biochrom 30 amino acid analyzer.

Note:  An additional run is necessary to analyze feed samples for methionine or tryptophan. 

• We use the following method for amino acids : Amino acids in feeds. AOAC official method 994.12. In: Official methods of analysis of AOAC International. Gaithersburg, Md: AOAC International, 2005;9–19.
• To analyze for tryptophan in foods and food and feed ingredients, we use AOAC official method 988.15. In: Official methods of analysis of AOAC International. Gaithersburg, Md: AOAC International, 2005;88–89.

Taurine in plasma, urine, tissue and feed: the sample preparation procedure is the same as complete amino acid analysis.  Analyses are done with a Biochrom 30 amino acid analyzer.

Whole blood taurine: samples are frozen and thawed twice to break the cells and release all taurine before further processing.

Normal Taurine Values (nmols/ml) for Cat & Dog

Interpretation

Reference for Cats
Reference for Dogs
Sample Submission Form (pdf)

Reference Papers

S. Delaney Article (pdf)
Torres Article (pdf)
Spitze Article (pdf)
Heinze Article (pdf)