| PROSTAGLANDIN INDUCED MILK FLOW TEST [PGIMFT]
Pregnancy diagnosis plays an essential role in decreasing days open in dairy farms; therefore, it is very important to select an accurate method for diagnosing early pregnancy. Besides traditional pregnancy diagnoses made by rectal palpation of the uterus from 40 to 60 days after AI and measuring the serum or milk progesterone concentration between 18 to 24 days after AI, there are several new possibilities to diagnose early pregnancy in dairy farms. However, it is very important to emphasize that before introducing any new diagnostic test, we need to make sure the accuracy of that particular test to be able to decrease the rate of iatrogenic pregnancy losses caused by prostaglandin or resynchronization treatments. |
- Labussiere et.al. (1992) reported diagnosis of pregnancy in cows based on the observation of milk ejection which in the case of CL maintenance results from the release of luteal oxytocin induced by intravenous administration of a non-luteolytic dose of PGF2 alpha .
- Examine all cows per rectum on day 18 post insemination to assess ovarian status.
- Perform PG-IMF test on the same day 3 hours after evening milking.
Preparation of Non-Luteolytic Dose of PGF2 alpha
- One ml of PGF2 alpha (lutalyse) which contains 5000 micro gram is reconstituted in 39 ml of distilled water to arrive at a final concentration of 125 micro gram/ml.
Protocol
- After washing the udder and teat, a sterile cannula is placed in the left fore teat to empty the cistern milk.
- Subsequently a non-luteolytic dose of 125 micro gram of PGF2 alpha is injected through the ear vein.
- After the injection the time duration of milk flow is recorded.
Inference
- Elicitation of milk let down reflex with free flow of alveolar milk within a few seconds after injection and lasting for 3-5 minutes is considered to have a functional CL/presence of conceptus.
- Absence of milk flow is indicative of non-functional CL.
Reason
- The prostaglandin induced milk let down response observed in pregnant animals could be attributed to the release of endogenous luteal oxytocin that was actively synthesised by the luteal tissue and was available for immediate release in response to PGF2 alpha resulting in alveolar milk ejection immediately by increasing the intra-mammary pressure within the cistern and enlargement of cisternal volume.
- https://www.pashudhanpraharee.com/factors-affecting-induction-of-milk-let-down-in-cows/
- https://www.semanticscholar.org/paper/EFFICACY-OF-PROSTAGLANDIN-INDUCED-MILK-FLOW-TEST-IN-Satish/d0e6d984841ae6cca057bb0185f8863a5d7d191c
