الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 201 |  |  |
| | | from | 201 | | |
Abstract
The present study was conducted on three experiments: Exp. 1) atotal
of 15 cows were used in this experiment. All cows were injected with two
doses of PGF2α with 11 days apart. All cows were examined three times
with trans-rectal ultrasonography (at the day of estrus after the second
PGF2α injection, 30 days post insemination, and 60 days post
insemination). All cows exhibited estrus following the second PGF2α
injection (range 46 – 96 hrs). all animals were inseminated at estrus (12
hrs from the start of estrus signs), and examined with ultrasonography to
determine the ovarian structures. The second ultrasonographic
examination (30 days post-insemination) for early pregnancy diagnosis
revealed that only 13 animals get pregnant. The third ultrasonographic
examination (60 days post-insemination) revealed that only 12 animals
still pregnant. Exp. 2) a total of 30 cows and heifers were used in 5 trials
for superovulation (10 animals for each trial) using different doses of
eCG (1000, 1500, 2000, 2500 and 2500 IU eCG + 10 ug GnRH) to
determine the dose at which we can obtain the most appropriate
superovulation response under local conditions. All animals in each trial
were synchronized with PGF2α, then injected with eCG at the 10th day of
the estrus cycle (day 0 = the estrus day), 48 hrs post eCG injection the
animals were injected with PGF2α for induction of estrus, at the day of
estrus all animals were inseminated every 12 hrs for 36 hrs, at the 7th day
after insemination the uteri of the inseminated animals were flushed non
surgically with two way Foley catheter to collect embryos. All animals
were examined three times with ultrasonography the 1st at the day of
second PGF2α injection (48 hrs post-eCG injection), the 2nd at the day of
insemination and the 3rd at the day of embryo recovery. The number of
responded animals were 3, 6, 7, 8 and 7 animals for the five trials
respectively.