The Heataid kit

How to use Progesterone Testing

Heataid may be used in a number of ways to investigate or improve fertility in a dairy herd and confirm pregnancy.

Milk Sample Collection: Milk samples should be representative of the whole milking. Try not to take samples from the fore milk or from the final strippings of the udder but to take a sample from a milk jar containing the whole milking. Where this is not possible take a sample mid way through milking.

Samples should be either analyzed within 3-4hours or kept in the fridge for no more than 12 hours before testing. Samples may be preserved for testing up to 3 weeks after collection by addition of a Lactab III preservative. These samples should be stored in a fridge.

Testing can be done either in the morning or evening milking times to fit in with your routine. It is however important to be consistent and always sample either in the morning or evening. This is because progesterone levels can be higher in the evening and a mixture of morning and evening samples may lead to confusion. Although this is not usually a great variability it can sometimes cause misleading results.

1. Heat prediction post calving

   Starting 25 days after calving sample and test twice a week until a low progesterone result is recorded (Strong pink colour). This is the first heat post-calving and is termed day 0.

   On day 15/16 after the first heat, start taking samples every other day. When you observe low progesterone (strong pink colour), watch closely for signs of heat. The optimal time to inseminate is between 18 hours and two days after obtaining a strong pink result. To fit in with an every other day testing regime insemination can be timed for the day following a low progesterone result in order to be sure of hitting the most fertile period.

2. Sampling 19 days after service

   If the cow is not pregnant, sampling on this day will give an early warning of return to service by showing low progesterone (strong pink colour). Take samples every other day and inseminate on the day following a recorded low progesterone result.

   If a weak colour is observed, this is an early indicator of pregnancy.

3. Sampling 24 days after service

   Cows apparently pregnant at day 19 should be re-tested on day 24. This is statistically the best day for confirming pregnancy.

4. Identifying heat in random cows and silent heat

   Sample every 3 to 5 days until you observe a series of pale pink (high progesterone) results followed by a strong pink (low progesterone). This indicates heat. Watch closely for signs of heat and inseminate on the following day.

5. Confirm Heat

   Take a milk sample on the day of suspected heat. A strong pink test result indicates the cow is in heat and ovulation is about to occur. The optimal time to inseminate is approximately 18 hours after obtaining a strong pink result.

6. Confirmation of Pregnancy

   Take a milk sample 19 days after insemination. A pale result strongly indicates the cow is pregnant. An additional sample taken on day 24 increases the accuracy of a pregnancy determination - up to 95% accuracy if a pale result is obtained on both tests.

   Pregnancy should be confirmed by your veterinarian since high progesterone could indicate mid ovarian cycle because of inaccurately timed insemination, or development of a persistent corpus luteum. Furthermore, cows diagnosed with high progesterone on day 19-23 may return to heat if the foetus is reabsorbed. A milk sample taken at the time of rectal palpation can be used in conjunction with palpation results.

7. Diagnose infertility problems (ovarian cysts)

   After veterinary confirmation of the presence of an ovarian cyst (by rectal palpation), Heataid is useful in determining the type of cyst. Take one milk sample at the day of palpation and 2 more samples at 7 day intervals.

   A strong pink test result (low progesterone) strongly indicates a follicular cyst or nonfunctional ovary.

   A pale test result (high progesterone) strongly indicates the presence of a luteal cyst or cystic CL.

8. In conjunction with prostaglandin

   Take a milk sample prior to injection with prostaglandin. If the corpus luteum (CL) is functional (pale result), continue with treatment.

9. Monitor fertility treatment

   Take a milk sample 10 days after treatment for a follicular cyst. If a pale result (high progesterone) is obtained, the prescribed treatment was effective.

   Take a milk sample 2 to 4 days after treatment for a luteal cyst or cystic CL. If a strong pink result (low progesterone) is observed, the treatment was effective.