Study of early pregnancy factor (EPF) in equine (Equus caballus).

The study is about the detection of the Early Pregnancy Factor (EPF) in horses to confirm pregnancy using a method called the rosette inhibition test. The research demonstrates the method’s effectiveness by showing its ability to detect EPF from 24-72 hours after mating until the second trimester in ponies and thoroughbred horses.

Introduction:

The study focuses on the Early Pregnancy Factor (EPF), an immunosuppressive protein found in the serum during early stages of pregnancy. The researchers aimed to determine whether their previously developed rosette inhibition test for equine EPF can be practically used in clinical settings to confirm pregnancy in mares.

Methods:

• The researchers conducted the rosette inhibition test on the serum of several ponies and thoroughbred mares, both pregnant and non-pregnant.
• The ponies included six pregnant and six non-pregnant Shetland ponies, and a female and a male Chinese pony.
• For the thoroughbreds, serum was collected from four non-pregnant and 13 pregnant mares during various stages of gestation.
• To further establish the validity of their test, the researchers also measured levels of progesterone and pregnant mare serum gonadotrophin (PMSG) in a Chinese pony, 3 and 6 months after mating.

Results:

• The results showed clear differences between the pregnant and non-pregnant ponies. Non-pregnant Shetland ponies had a rosette inhibition titre (RIT) of 6.0+/-1.0 with a negative EPF, whereas pregnant ones had an RIT of 9.2+/-0.4 with a positive EPF.
• These results were used to diagnose the pregnancy of the female Chinese pony (3 months after mating), which also showed an RIT above 10 and a positive EPF result. The presence of PMSG and progesterone in the pony’s serum was also confirmed.
• In both ponies and thoroughbred mares, EPF appeared in the blood 24-72 hours after mating and could be detected until the second trimester, after which it disappeared.

Conclusions:

• The study concluded that the detection of the EPF using the rosette inhibition test can be a useful tool for diagnosing pregnancy in equine species.
• As it can provide positive results as early as 24-72 hours after mating until the second trimester, it offers a clinically viable method of early pregnancy detection in equine species like ponies and thoroughbred mares.