DWR Diagnostics

Reproductive Function Tests

REPRODUCTIVE FUNCTION TESTS

DOGS:

OVULATION DETECTION FOR TIMING OF MATING

Since ovulation may occur at varying times after the onset of vulval bleeding, progesterone measurement can used to determine the optimum time for mating. For most bitches, blood sampling for progesterone measurement should begin around 7 days after the onset of vulval swelling and bleeding. Bitches are then re-tested every 2–3 days until ovulation occurs.

Tests for detection of ovarian tissue
in the bitch

A. When the bitch is showing signs of oestrus there are several tests which can detect ovarian tissue

  1. Vaginal smear – cytological changes in vaginal epithelium can be used to identify ovarian activity
  2. Measurement of oestrogen – this increases in late anoestrus, prooestrus and early oestrus but then declines
  3. Measurement of progesterone – this increases in late oestrus and remains high in dioestrus (ie for 60 days post ovulation)

B. When there are no signs of oestrus:

  1. Anti-Mullerian Hormone – determines the spay status of dogs after they have reached the age of sexual maturity. AMH levels remain constant throughout the cycle. Animals that have been neutered will have undetectable levels of AMH. A positive AMH test indicates the presence of ovarian tissue, but a negative result does not fully exclude the presence of ovarian remnants. An inconclusive AMH result cannot distinguish between the intact and spayed conditions.
  2. In case of inconclusive results, stimulation testing may be required to induce production of oestrogen from the ovarian remnant with either hCG or GnRH:

a. Collect basal sample in gel or heparin tube to provide 1 ml serum/plasma

b. Inject hCG (Chorulon, Intervet) at a dose of 44 IU/kg IM

c. Take a second sample 2h later, separate the serum/plasma and label ‘post’

d. Request OESTRADIOL.

Tests for detection of testicular tissue

  1. Anti-Mullerian Hormone – may be used as a cryptorchid test to detect testicular tissue. This test may also be used in young animals under 3 years old. AMH levels should be very low (undetectable) in correctly castrated animals.
  2. Dynamic testosterone test – used to diagnose cryptorchidism or to evaluate testicular function. In normal dogs there is significant variation in testosterone production throughout the day. Single samples could potentially be measured at a trough of production and so stimulation testing using hCG is usually performed to detect testicular tissue.

a. Collect basal sample into a plain gel or heparin tube to give 1 ml serum /plasma

b. Inject hCG (Chorulon, Intervet) at a dose of 44 IU/kg IM

c. Collect second sample 60 – 120 minutes later

d. Separate the serum and label the tubes pre- and post and request TESTOSTERONE.

REPRODUCTIVE FUNCTION TESTS

CATS

Tests for detection of ovarian tissue

Anti-Mullerian Hormone – determines the spay status of cats after they have reached the age of sexual maturity. AMH levels remain constant throughout the cycle. Animals that have been neutered will have undetectable levels of AMH. A positive AMH test indicates the presence of ovarian tissue, but a negative result does not fully exclude the presence of ovarian remnants. An inconclusive AMH result cannot distinguish between the intact and spayed conditions.

In case of inconclusive results, a dynamic function test may be necessary:

A. When the queen is showing signs of oestrus, ovarian tissue can be detected with an hCG stimulation test.

Progesterone is measured pre- and post administration of hCG, which stimulates ovulation.

  1. Take a basal plain serum or heparin sample (not serum gel) to give 0.5 ml serum/plasma. Separate and freeze
  2. Inject hCG (Chorulon, Intervet) at a dose of 44 IU/kg IM
  3. Take a second sample 2 weeks later
  4. Separate the serum/plasma and ensure the tubes are labeled pre- and post
  5. Request PROGESTERONE

If the queen is presented shortly after a period of oestrous behaviour, it is best to delay investigations until the signs recur, typically within about 3 weeks, and then investigate as above.

B. When there are no signs of oestrus e.g. in the winter time when the queen is likely to be in anoestrus, stimulation testing is required to induce production of oestrogen from the ovarian remnant. This can be done with hCG (dose as above).

  1. Collect basal sample in serum or heparin tubes to provide 1 ml serum/plasma
  2. Inject hCG
  3. Take a second serum sample 2h later
  4. Ensure the tubes are labelled with sample times
  5. Separate the serum/plasma and request OESTROGEN

Tests for detection of testicular tissue

A. Anti-Mullerian Hormone – may be used as a cryptorchid test to detect testicular tissue. This test may also be used in young animals under 3 years old. AMH levels should be very low (undetectable) in correctly castrated animals.

In case of inconclusive results:

B. In normal cats there is significant variation in testosterone production throughout the day. Single samples could potentially be measured at a trough of production and so stimulation testing is usually performed to detect testicular tissue using hGC.

  1. Collect basal sample into a plain serum or heparin tube to give 1 ml serum /plasma
  2. Inject 44 IU/kg IM hCG (Chorulon, Intervet)
  3. Collect second sample 60 mins later
  4. Separate the serum and label the tubes pre- and post and request TESTOSTERONE.

Test Protocols

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