Skip to Main Content

The University of Tennessee

The College of Veterinary Medicine

Frequently Used Tools:



Diagnostic » Endocrinology » General Information



Endocrinology

Printer Friendly Version of this page

.

GENERAL INFORMATION

  1. GENERAL INFORMATION: Proper sample collection and handling are essential to accurate test results. 
    • Do not send whole blood for any test procedure. 
    • Please do not send samples in serum-separator tubes (polymer-gel tubes). This causes hemolysis of samples and the gel is know to precipitate drugs. 
    • Please label sample containers adequately 
      • owner’s name
      • animal name
      • test desired
      • time of collection (baseline; post-stim.; etc.)
    • For serum samples: clot at room temperature, centrifuge within 1 hour, remove serum and freeze. Alternatively, store blood samples in the refrigerator for 2 to 4 hours to clot, centrifuge, remove serum and freeze.
    • For plasma samples: use EDTA tubes, centrifuge and remove plasma within 15 minutes and freeze. 
    • EXCEPT for thyroid samples, ship samples in insulated container with adequate cool packs and insulating materials (peanuts, paper), being careful to pack to avoid leakage or breakage (plastic tubes are recommended). Seal lid juncture with tape to preserve cold. Ship samples Monday-Thursday by overnight delivery service. Do not send immediately prior to a holiday! Be sure to include a brief history of the case, and especially include the sex status and age of the animal.

    ..

  2. THYROID FUNCTION:  DOG, CAT, HORSE, FERRET, BIRD  (All samples are serum; do not send in polymer gel tubes).
    (Back to Endocrinology Tests)
    1. T3 and/or T4 - Prepare 1.0 ml of serum (sufficient for both tests). Minimum of 0.2 ml serum required. Consider requesting the combined T4/TSH assay for dogs.

    2. TRH Stim - Consider requesting the combined T4/TSH assay for dogs instead. Take a pre-sample using T3/T4 procedure; then administer 0.05 mg/kg to a maximum 1 mg TRH, intravenously, and collect second sample 6 hrs later. For Birds: Collect baseline serum sample (0.2 ml); then administer 50 µg/kg of TRH (100 µg/ml conc. in saline) IV. Collect post-TRH sample at 2 hours (0.2 ml).

    3. Post Pill T4 - Collect serum (1.0 ml) post-pill at 4-6 hrs.

    4. T3 Suppression (cat) - Collect basal serum sample for T4. Administer liothyronine (T3 or Cytobin™) at an oral dose of 25 µg 3x/day for 7 doses. Collect sample for T4 on morning of 3rd day, 4 hrs after 7th dose of liothyronine. NOTE!: Request T3 determination also, if there is concern for owner compliance, or drug intake by the cat.

    5. Canine TSH - Prepare 1.0 ml of serum. Freeze sample and ship next-day delivery with proper packaging and cool packs.

  3. ADRENAL FUNCTION:  Do not send samples in polymer gel tubes). 
    (Back to Endocrinology Tests)

    NOTE! All adrenal function tests use serum samples.

    1. Cortisol - ACTH Stim Test - DOG, CAT. Collect baseline serum sample (1.0 ml). For dogs, give ACTH gel at 2.0 IU/kg (IM). Maximum dose of 40 IU in dogs. Take post-ACTH serum sample 2 hrs later (1.0 ml). If using synthetic ACTH (Cortrosyn™), give 5 µg/kg IV, and collect post-ACTH serum sample 1 hr later.

      For cats      , use Cortrosyn™ as for dogs, but give 25 µg/kg, IM (maximum dose of 125 µg/cat). Collect post-ACTH serum sample at 30-minutes and 60-minutes. 

      For horse, collect baseline serum sample (1.0 ml), administer 200 IU of gel ACTH (IM) and collect post-ACTH serum sample 2 hrs later. If using synthetic ACTH (Cortrosyn™), collect baseline serum sample (1.0 ml), administer 1.0 mg. total of Cortrosyn™ IV, and collect post-ACTH serum sample 1-hour later (1.0 ml).  

    2. Cortisol-Dex Supp/ACTH Stim Test - DOG, CAT, HORSE. Collect baseline serum sample (1.0 ml). Administer dexamethasone at 0.1 mg/kg (IV).  For horse, use 10 mg Dex (total dose, IV). Take a post-Dex serum sample 4 hrs later.  Following the Post-Dex collection, perform the Cortisol-ACTH Stim Test as above.

    3. Cortisol-Low Dose Dex Supp Test - DOG. Collect baseline serum sample (1.0 ml).  Administer dexamethasone at 0.01 mg/kg (IV).  Collect Post-Dex serum samples at 4, 6 and 8 hrs (1.0 ml).

    4. Cortisol-High Dose Dex Supp Test - DOG.  Collect baseline serum sample (1.0 ml).  Administer dexamethasone at 0.1 mg/kg (IV).  Collect Post-Dex serum samples at 4, 6 and 8 hrs (1.0 ml).

    5. Cortisol - Overnight Dex Supp Test - Horse.  Collect baseline serum sample (1.0 ml) at 5:00 p.m.  Inject 40 µg/kg dexamethasone (IM).  Collect second serum sample between 8:00 a.m. and 12:00 noon next day.

    6. Cortisol-Dex Supp/TRH Stim Test - Horse.  Collect baseline serum sample (1.0 ml) followed by injection of dexamethasone (40 µg/kg, IV). Collect second serum sample (1.0 ml) three hours post-dexamethasone followed by TRH* injection (1.2 mg/horse). Collect third serum sample (1.0 ml) 30 minutes post-TRH.  Collect fourth serum sample (1.0 ml) 24-hours post-dexamethasone.  

      *Thyrotropin-Releasing Hormone (acetate salt) is available from Sigma Chemical Co., St. Louis, MO. (800-325-3010).

      Canine TSH -- Prepare 1.0 ml of serum.  Freeze sample and ship "NEXT-DAY" delivery with proper packaging and cold packs. 

    7. Adrenal Panel for Dogs and Cats (ACTH Stim) - Test for congenital adrenohyperplasia-like syndrome (dog, cats), or Alopecia-X Atypical Cushings Syndrome.   Note: All adrenal function tests use serum samples.

      Collect baseline serum sample (1.0 ml.). Centrifuge samples as soon as possible, separate and freeze.  Administer the ACTH Stim test as above (3A). Collect Post-ACTH serum sample (1.0 ml) at 1 hr (2 hrs if gel-ACTH is used). Centrifuge samples as soon as possible, separate and freeze.  (NOTE: If samples are grossly hemolyzed, repeat test in one week).

      Ship frozen samples preferably in styrofoam container, next day delivery, on Monday - Thursday with 1-2 cool-packs (add insulating materials [peanuts; paper], and seal styrofoam seams with tape). The following hormones will be assayed: Cortisol,  Estradiol, Androstenedione, 17-Hydroxyprogesterone, Progesterone and Aldosterone. The assay is run each week.

      (DHEAS is no longer available)

    8. Adrenal Panel for Ferrets - Test for adrenocortical disease in ferrets.  Collect baseline serum sample (0.5 ml). Centrifuge samples as soon as possible, separate and freeze. Ship frozen samples as for the Adrenal Panel for Dogs method above (3A). The following hormones will be assayed: Estradiol, Androstenedione and  17-hydroxyprogesterone. The assay is run each week.
    9. Adrenal Panel for Cats. -- Collect baseline serum sample (0.5 ml), administer Cortrosyn ACTH Stim Test as in (3A).  Collect post-ACTH serum samples at 30-minutes and 60-minutes. Centrifuge samples as soon as possible, separate and freeze. See hormones assayed under Canine Adrenal Panel (3G)

       
    10. Adrenal Panel for Rabbits (neutered rabbits only)
      Collect baseline serum sample (1 ml).  Centrifuge sample as soon as possible then separate and freeze.  Hormones analyzed are progesterone, 17-hydroxyprogesterone, androstenedione, testosterone, and cortisol.

       

  4. REPRODUCTIVE HORMONES - DOG, CAT, HORSE, FERRET. 
    (Use Serum; do not send in polymer gel tubes).
    (Back to Endocrinology Tests)
    1. Estradiol, Progesterone or Testosterone  
      • Collect 0.5 ml of serum for each. 
      • Centrifuge samples as soon as possible and separate serum.

    2. Testosterone-HCG Stim - For cryptorchidism detection in the horse. 
      • Collect baseline serum sample (1.0 ml) in the morning hours (a.m.).  
      • Administer HCG at 10,000 units total dose (IV). Collect Post-HCG serum sample (2.0 ml) 72 hours later (a.m.).  
      • Centrifuge samples as soon as possible and separate serum. 
      • For completeness of castration in dogs and cats. 
        • Collect baseline serum sample (1.0 ml). 
        • Administer HCG at 50 IU/kg IM. 
        • Collect Post-HCG serum sample at 2 hours. 
        • Centrifuge samples as soon as possible and separate serum.

    3. Progesterone - HCG Stim - For detecting ovarian remnant in dogs, cats or ferrets.
      • Collect baseline serum sample (0.5 ml). 
      • Administer 50 IU of HCG/kg I.M. Collect post HCG samples at 7 and 21 days
      • Process samples per general information guidelines.

         
    4. Progesterone-hCG Stim -- For detecting ovarian remnant in rabbits
      Collect baseline serum sample (0.5 ml) then administer 50 IU hCG IV. Collect serum sample (0.5 ml) 4 days later

       
    5. Testosterone-hCG Stim -- For detecting retained testicular tissue in rabbits
      Collect baseline serum sample (0.5) then administer 1500 IU hCG IM. Collect serum sample (0.5 ml) 3 hours later.
  5. ERYTHROPOIETIN - DOG and CAT (Use Serum: NOTE! Do not send in polymer gel tubes.).
    •  Collect serum sample (2.0 ml) between 8-10 a.m..
    • Centrifuge as soon as possible and transfer serum to plastic tube. 
    • Freeze immediately. 
    • Test results will not be valid if samples are grossly hemolyzed. Do not send severely hemolyzed samples.  
    • Ship samples as per directions for the dog adrenal panel, 3G above. 
      (Back to Endocrinology Tests)

  6. INSULIN - DOG. (Use serum.  NOTE! Do not send in polymer gel tubes.) 
    • Fast dog until serum glucose concentration is < 60 mg/dl. 
    • Collect serum sample (1.0 ml) for insulin determination. 
    • Centrifuge sample as soon as possible, separate and freeze. 
    • Ship sample as per directions for the dog adrenal panel, 3H above.
      (Back to Endocrinology Tests)

.

If you have questions, please call the lab at (865) 974-5638


Dog Bite Prevention PetStock - A Benefit Concert to Aid Animals UT Veterinary MRI