THE RELATIONSHIP BETWEEN PLASMA PROGESTERONE CONCENTRATION AND EMBRYO PRODUCTION IN DAIRY COWS SUPEROVULATED WITH FSH OR PMSG

Document Type : Original Article

Authors

Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt.

Abstract

Fourteen primiparous lactating cows, 3.5 to 4.5 years old in a military dairy farm nearby Cairo (Egypt) were used in this study. Following synchronization, the animals were randomly assigned into two groups; the first group (6 cows) was super-ovulated with a total dose of 32 mg FSH- P whereas the second group (8 cows) was treated with 3000 iu PMSG. Embryos were collected non-surgically on day 7 (day of estrus = day 0). Plasma samples were taken from cows of both groups on day-4 (first day of gonadotrophin treatment), day-2 (day of PGF2q injection), day 0 (day of estrus) days 1,3,5 post-estrus and day 7 (day of recovery) for progesterone assay.
The results revealed that FSH was more effective as a super ovulatory agent than PMSG. Higher (P < 0.05) ovulation state (11.33 = 1.85 vs 6.63 « 1.14), number of embryos recovered per donor (5.17 1.20 vs 2.44 = 0.45) as well as number of transferable embryos (4.1621.0) vs 1.8620.42) were obtained from FSH than from PMSG-treated cows. However, more follicles (> 10 mm) were palpated in the PMSG-treated group (2.0020.40 vs 0.33 90.19; P < 0.01). Coefficients of correlation between progesterone concentration at initiation of superovulation and each of the ovulation rate, number of embryos recovered and number of transferable embryo were higher in FSH than in PMSG-treated cows. When the data of both groups were pooled, the respective correlations (0.74 0.69, 0.67) were still highly (P < 0.01) significant. Moreover, significant correlations were estimated between progesterone concentration and the mentioned parameters in FSH group at the day of recovery.
This study revealed that measurement of plasma progesterone concentration can serve as a prognostic tool to predict the yield of fertile eggs and quality of embryos.

Main Subjects