الفهرس 
I-introductionOnly 14 pages are availabe for public view
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Abstract
The present work was planned to: 1. To establish a more efficient and reliable protocol for synchronization in small ruminants in Egypt. 2. To establish a more efficient and reliable protocol for superovulation and embryo evaluation in small ruminants in Egypt. 3. To investigate whether the so-called day 0 Protocol can be performed without the utilization of ultrasonography and how it would compare to other superovulation protocols in small ruminants 4. To evaluate the effect of season, age and repeated gonadotrophin treatment on ovarian response to superovulation. 115 animals used in this study (55Barki ewes + 60 Baldy does) raised in the farm of the faculty of veterinary medicine Sadate city Menofia university during the period between(August 2010 to February 2012) 1. Estrus synchronization: A total of 50 ewes and 50 does were used, randomly divided onto 5 equal groups Group 1: sponge+ eCG. Intravaginal Sponges were inserted for 14 days for ewes and 17days for does plus 400 I.U of eCG before removal of the sponge by 48h. Incidence of estrus was 100% for both ewes and does. The onset and duration of estrus had an average mean of (31.8±1.323) and (33.1±1.353) for does and (30.4±1.7) and (26.3±1.54) for ewes. Pregnancy ratio of 80% for both ewes and does. An average litter size of (1.57± 0.20) and (1.43± 0.26) for does and ewes respectively. Group 2: sponge + eCG+PGF2α. Intravaginal Sponges were inserted for 14 days for ewes and 17days for does plus 400 I.U of eCG before removal of the sponge by 48h + injection of 0.6ml Estrumate. Incidence of estrus was 100% for both ewes and does. The onset and duration of estrus had an average mean of (24.7±1.62) and (22.9±1.37) for does and (28.2±1.56) and (27.7±1.37) for ewes. Pregnancy ratio of 90% for does and 80% for ewes. An average litter size of (1.87±0.29) and (1.37±0.18) for does and ewes respectively. Group 3: sponge + eCG+PGF2α+GnRH. Intravaginal Sponges were inserted for 14 days for ewes and 17days for does plus 400 I.U of eCG before removal of the sponge by 48h + injection of 0.6ml Estrumate plus 1ml Receptal at the time of mating. Incidence of estrus was 100% for both ewes and does. The onset and duration of estrus had an average mean of (27±1.74) and (23.7±1.32) for does and (27.3±1.32) and (26.7±1.51) for ewes. Pregnancy ratio of 100% for both does and ewes. An average litter size of (2.2±0.25) and (1.4±.16) for does and ewes respectively. Group 4: GnRH+PGF2α+GnRH. Each animal was given an IM injection 1 ml Receptal and 7 days later an IM injection 0.6ml of Estrumate and a second dose of Receptal was injected to all ewes 48 h later after the injection of Estrumate Incidence of estrus was 100% for ewes and 90% does. The onset and duration of estrus had an average mean of (24.5±1.48) and (23±1.68) for does and (29.6±1.69) and (24.7±1.38) for ewes. Pregnancy ratio of 80% for does and 90% for ewes. An average litter size of (1.5±0.27) and (1.25±0.125) for does and ewes respectively. Group 5: PGF2α-PGF2α-eCG. Animals in this group received treatments composed of two IM injections of 0.6ml of Estrumate with 11days apart plus an intramuscular injection of 400 I.U of eCG with the second PGF2α injection Incidence of estrus was 100% for ewes and 90% does. The onset and duration of estrus had an average mean of (26.88±1.8) and (22.44±1.79) for does and (29.1±2.2) and (27.2±1.7) for ewes. Pregnancy ratio of of70% for does and80% for ewes. An average litter size of (2±0.36) and (1.37±0.18) for does and ewes respectively. 2. Superovulation: Experiment 1: Effect of dose of eCG in Superovulatory response. Five cyclic animals were used in each group; all animals came into standing estrus following synchronization and responded to the Superovulatory treatment (≥3CL). For does, ovulation rate mean was (0.53±0.08), (0.69±0.05) and (0.48±0.05) , the overall mean of corpora lutea per does was (5.4±0.75), (11.6±1.28) and (9±1.22) , The anovulatory follicles ≤5mm had overall mean per doe of (5.2±1.32), (5±1.04) and (10±1.41) and The total number of collected embryos had an overall mean of (2.8±0.86),(7±0.55) and (6.2±1.06), for dose rate of 800 IU, 1000 IU and 1200 IU of eCG respectively. There was a significant difference between the different doses and the best dose rate was1000IU of eCG For ewes, ovulation rate mean was (0.74±0.047), (0.75±0.045) and (0.62±0.05) , the overall mean of corpora lutea per ewe was (6.8±0.96), (13.2±2.1) and (14.6±2.01), The anovulatory follicles ≤5mm had overall mean per ewe of(3.0±0.98), (4.6±1.28) and (9.4±1.94) and The total number of collected embryos had an overall mean of (4.6±0.51), (7.8±1.3) and (9.2±1.02) for dose rate of 1000 IU , 1200 IU and 1500 IU of eCG respectively. There was a significant difference between the different doses and the best dose rate was1200 IU of eCG Experiment 2: Effect of season on the response to superovulation. For does, ovulation rate mean was (0.69±0.05) and (0.57±.01), the overall mean of corpora lutea per does was (11.6±1.28) and (8.8±1.06), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (7.2±1.5) and The total number of collected embryos had an overall mean of (7±0.55) and (5.8±0.80) for the breeding and out of breeding season respectively. For ewes, ovulation rate mean was (0.75±0.045) and (0.62±0.04), the overall mean of corpora lutea per ewe was (13.2±2.1) and (11.8±1. 6), The anovulatory follicles ≤5mm had overall mean per ewe of (4.6±1.28) and (6.8±0.97) and The total number of collected embryos had an overall mean of (7.8±1.3) and (5.6±0.81) for the breeding and out of breeding season respectively. There was on significant difference beteen the breeding and non breeding season for both seep and goats. Experiment 3: The effect of time of injection of Superovulatory drug: For does, ovulation rate mean was (0.69±0.05), (0.52±0.021) and (0.41±0.011), the overall mean of corpora lutea per does was (11.6±1.28), (9.4±0.64) and (7.75±0.62), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04), (8.5±0.86) and (10.75±0.48) and The total number of collected embryos had an overall mean of (7±0.55), (7.2±0.63) and (4±0.4), for 48hr or 24hr before and at the time of removal of sponge respectively. There was a significant difference between the three timing of administration with the best results obtained when injection was 48h before removal of the intravaginal sponge. Experiment 4: The effect of injection of GnRH before insemination: For does, ovulation rate mean was (0.69±0.05) and (0.36±0.03), the overall mean of corpora lutea per does was (11.6±1.28) and (5.6±0.89), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (10±1.5) and The total number of collected embryos had an overall mean of (7±0.55) and (2.8±0.66) for injection and without injection of GnRH before respectively. For ewes, ovulation rate mean was (0.75±0.045) and (0.61±0.02), the overall mean of corpora lutea per ewe was (13.2±2.1) and (11±2.62), The anovulatory follicles ≤5mm had overall mean per ewe of (4.6±1.28) and (6.6±1.36) and The total number of collected embryos had an overall mean of (7.8±1.3) and (7±1.64) for injection and without injection of GnRH before respectively. There was a significant difference between both treatments, the results indicated that injection of GnRH increase the ovulation rate and decrease the anovulatory follicles. Experiment 5: Effect of repeated superovulation: For does, ovulation rate mean was (0.69±0.05) and (0.52±0.02), the overall mean of corpora lutea per does was (11.6±1.28) and (6.66±0.88), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (5±0.57) and The total number of collected embryos had an overall mean of (7±0.55) and (4.66±0.33) for first time and repeated superovulation respectively. For ewes, ovulation rate mean was (0.75±0.045) and (0.56±0.06), the overall mean of corpora lutea per ewe was (13.2±2.1) and (7.75±2.3), The anovulatory follicles ≤5mm had overall mean per ewe of (4.6±1.28) and (5.25±0.63) and The total number of collected embryos had an overall mean of (7.8±1.3) and (4.5±0.86) for first time and repeated superovulation respectively. No significant differences between the first and the second superovulation indicating that the repeated superovulation doesn’t affect in the response to superovulation. For both sheep and goats. Experiment 6: Effect of parity. For does, ovulation rate mean was (0.69±0.05) and (0.6±0.05), the overall mean of corpora lutea per does was (11.6±1.28) and (5.8±0.95), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (4.2±0.97) and The total number of collected embryos had an overall mean of (7±0.55) and (4.20±0.73) for adult and young age animals respectively. For ewes, ovulation rate mean was (0.75±0.045) and (0.72±0.01), the overall mean of corpora lutea per ewe was (13.2±2.1) and (7.25±2.01), The anovulatory follicles ≤5mm had overall mean per ewe of (4.6±1.28) and (2.75±0.75) and The total number of collected embryos had an overall mean of (7.8±1.3) and (4.25±1.1) for adult and young age animals respectively. There was a significant difference between the response of the adult (multiparous) and young (nulliparous) animals in the response to superovulation indicating that the adult animals respond better than the young for both sheep and goats. Experiment 7: Day 0 protocol for superovulation: For does, ovulation rate mean was (0.69±0.05) and(0.44±0.05), the overall mean of corpora lutea per does was (11.6±1.28) and (7.5±1.5), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (9±0.71) and The total number of collected embryos had an overall mean of (7±0.55) and (3.75±1.108) for traditional and Day 0 protocol for superovulation respectively. No significant differences between the two protocols in the response to superovulation. Experiment 8: Superovulatory treatment without progesterone sponges. For does, ovulation rate mean was (0.69±0.05) and (0.6±0.04), the overall mean of corpora lutea per does was (11.6±1.28) and (8.3±1.3), The anovulatory follicles ≤5mm had overall mean per doe of (5±1.04) and (5.33±0.33) and The total number of collected embryos had an overall mean of (7±0.55) and (6±0.57) for traditional and without sponge for superovulation respectively. Experiment 9: Superovulatory treatment with synchronization by double intramuscular injections of PGF2α 11days apart. For ewes, ovulation rate mean was (0.75±0.045) and (0.67±0.02), the overall mean of corpora lutea per ewe was (13.2±2.1) and (11.8±1.8), The anovulatory follicles ≤5mm had overall mean per ewe of (4.6±1.28) and (5.75±1.3) and The total number of collected embryos had an overall mean of (7.8±1.3) and (7.5±1.4) for sponge and PGF2α 11days apart respectively. 3. Transfer of embryos: 5does and 5 ewes received two morula out of them 2does and 2 ewes became pregnant. 2does and 2ewes received 2morula+blastocysts, the two does and one ewe became pregnant 2 does and 2ewes received 2 morula+2 blastocysts, one doe and one ewe became pregnant. One doe and one ewe received 3blastocysts, no pregnancy was recognized. The pregnant animals were followed up, 3 does and 3ewes complete the pregnancy period and each animal give one offspring after normal parturition.