Estrous Onset Research Articles

Estrous Responses of Kejobong Goat Synchronized using Progesterone Hormone

The purpose of this study was to examine the effect of age based on estrous responses. Material used in this study were 36 heads of Kejobong doe, with average body weight 32.21±1.41 kg; average Body Condition Score (BCS) 2.5; black fur color; had given birth, with age ranged 1-1.5 years old (P1, n = 7); 1.5-2 years old (P2, n = 15) and 2.5-3 years old (P3, n = 14). The sample was then put on a vaginal sponge containing 20 mg of Medroxy Progesterone Acetate (MPA) in the reproductive tract for 14 days. Parameter observed were estrous onset; estrous behavior including restlessness, aggressiveness, frequent wagging tail and climbing the feeder tray or other livestock and vulva condition including vulva temperature, swelling vulva and vulva color. Result showed there was no significant difference (P>0.05) between P1, P 2 and P3 on estrous onset, estrous behavior and vulva condition. In conclusion, the estrous response of Kejobong goat which is synchronized to estrous with the hormone progesterone is not affected by the age and have the same estrous response after reaching maturity.

Metabolite abundance in bovine preovulatory follicular fluid is influenced by follicle developmental progression post estrous onset in cattle.

Introduction: Preovulatory follicle response to the luteinizing hormone (LH) surge leads to metabolic, molecular, and functional changes in the oocyte and somatic follicular cells from the onset of estrus to ovulation. Follicular fluid contains metabolites, miRNAs, proteins, and hormones that are byproducts of follicular metabolism and support cellular processes of oocyte, cumulus, and granulosa constituents. Numerous studies have highlighted the importance of follicular fluid composition to support fertility, but critical gaps exist toward understanding dynamic modifications in the follicular fluid metabolome from estrous onset to ovulation. The hypothesis was that abundance of follicular fluid metabolites is dependent on follicle progression post LH surge and variability in follicular fluid metabolome profiles indicate key processes required for preparation of the follicle and oocyte for optimal fertility. The objective was to generate preovulatory follicular fluid metabolome profiles and discern differences in the metabolome of preovulatory follicular fluid samples collected at onset of estrus, 11 h post estrous onset, and 18 h post estrous onset. Methods: Estrus was synchronized in non-lactating Jersey cows (n=40) and follicular fluid was collected immediately after the first observed standing mount (hr 0) or at approximately h 11 or 18 after the first standing mount. Ultra-High-Performance Liquid Chromatography-High Resolution Mass Spectrometry was performed on preovulatory follicular fluid samples (n = 9 collected at hr 0, 9 at h 11, and 10 at h 18) and a multiple linear model was performed to determine if time post estrous onset impacted metabolite abundance. Results: Metabolites influenced by time post estrous onset were tested for enrichment in KEGG pathways. Ninety metabolites were identified in follicular fluid samples. Twenty metabolites differed in abundance among timepoints post estrous onset (p ≤ 0.05). Pathways corresponding to amino acid and energy metabolism were enriched with metabolites impacted by time post estrous onset (FDR ≤ 0.10). Discussion: Results from the current study indicate early response to the LH surge to increase bioavailability of amino acids and metabolites used by the cumulus and granulosa cells for energy production and shuttled into the oocyte to support meiotic maturation. Such metabolites may later be used by the ovulatory follicle for protein production.

Fecundity profiles and physiological traits of Iraqi Awassi ewes supplemented mulberry leaves powder extract

The fecundity efficacy of ewes depends on reproductive hormones, ovarian activity so the current research was designed to improve the fecundity of Iraqi anestrous ewes by mulberry leaves (Morus alba) powder extract supplementation. 30th healthy non-pregnant ewes aged 2-3.5 year outbreeding season were divided into equal three groups, 1st group represent a (control) had fed the standard diet, second and third group represent T1 and T2 supplemented 15 and 30 mg/kg mulberry powder extract, respectively, for 40 day before sponge insertion. At day 28th of beginning supplementation the intra-vaginal sponge were inserted for 12 days. After sponges eliminated, estrous onset reported and blood collected before 20 and after 23 & 40 hrs of VSPR to estimate FSH, LH, progesterone and Estradiol concentration. Also, the fecundity, lambing and prolificacy rates had manifested. The results recorded a significant elevation in FSH, estradiol and LH while progesterone registered significant decreased in T1 &T2 comparing with C at 23 & 40 hr after VSPR. Also the fecundity, lambing rates were significantly higher in T1 &T2 in comparing with C. In concluded, that the mulberry leaves powder extract can augment the fecundity in anestrus Iraqi ewes by enhancing the fecundity profile and prolificacy rate.

Fertility restoration of racing mare with persistent corpus luteum.

Background and Aim:Persistent corpus luteum (PCL) causes anestrus in mares. This study aimed to determine the effect of intrauterine prostaglandin F2α (PGF2α) treatment on PCL of racing mares to restore fertility.Materials and Methods:Twelve racing mares suspected with PCL were diagnosed using transrectal palpation and confirmed by serum progesterone (P4) concentration measurement. PGF2α was infused intrauterine, followed by serum collection at 24, 48, and 72 h after. Estrous symptoms were monitored, and mating was conducted on day 3 of estrus with an earlier injection of 8.4 μg gonadotropin-releasing hormone twice a day. Transrectal palpation was performed on days 21-30 to observe the corpus luteum. Pregnancy diagnosis was performed rectally on 40-45 days post-mating and confirmed using Doppler ultrasound scanning.Results:Eleven of the 12 mares had PCL. There was a dramatic reduction in the P4 concentration following PGF2α treatment of mares with PCL. All mares exhibited estrus 2.6±0.55 days post-treatment with a P4 concentration of 0.12±0.12 ng/mL. Rectal palpation and P4 concentration on 21-30 days after estrous onset showed that all mares were ovulating. The evaluation of P4 concentration on days 40-45 post-mating showed that all mares were still in the luteal phase. However, the pregnancy rate was only 54.5% based on rectal palpation and Doppler ultrasound scanning.Conclusion:Treatment of PCL in racing mares with an intrauterine infusion of PGF2α restored the estrous cycle and induced ovulation and pregnancy.

Superovulatory response and embryo quality in Boer does following dietary supplementation with different sources of omega-3 and omega-6 fatty acids during the breeding season

The purpose of this study was to determine effects of various sources of omega-3 and omega-6 fatty acids on ovarian response and embryo quality in Boer does when there was a superovulation treatment regimen imposed. Pluriparous does were randomly assigned to be treated with 300 g of one of four experimental supplements containing linseed oil (LO), soybean oil (SO), palm oil (PO), or a control supplement without fatty acids (CO), for 15 days. Does were fitted with a controlled internal drug release (CIDR) device containing 0.3 g progesterone for 7 days. At 48 h before CIDR withdrawal, does were treated with 80 mg follicle-stimulating hormone (FSH) administered at 12 h intervals. Embryos were collected 7 days after the last natural mating. Estrous response and interval between CIDR withdrawals to estrous onset were similar between treatments (P > 0.05). Number of ovulations was similar for does in the different groups (10.0, 9.2, 7.0, and 7.0, in LO, SO, PO, and CO, respectively; P > 0.05). There was premature luteal regression in does of the SO, PO, and CO groups, except in LO group. The LO-treated does had a larger (P < 0.05) mean number of ova/embryos recovered than does of SO, PO, and CO groups (7.2, 2.0, 0.2, 0.2, respectively) and transferable embryos (5.1, 1.4, 0.2, 0.2, respectively). These results indicate that including LO in supplements may be a feasible strategy for preventing premature luteal regression and improving embryo quality in goats treated to induce follicular super-stimulation for induction of superovulation.

Multiple matings modify the estrous length, the moment of ovulation, and the estradiol and LH patterns in ewes.

In several species, mating reduces the estrous length and advances ovulation. The aim of this study was to determine if multiple matings reduces the estrous length and modifies the moment of ovulation, as well as the estradiol and LH patterns in ewes. The estrous cycle of Corriedale ewes was synchronized, and the onset of receptivity was monitored every 3 h with rams, avoiding mating. At the estrous onset, ewes were assigned to two experimental groups (n=10 each): 1) estrous was monitored every 3 h with a ram avoiding mating (group CON), and 2) a ram was allowed to mate and ejaculate once every 3 h (group MAT). The ovaries were scanned with transrectal ultrasonography and blood samples were collected for measuring 17β-estradiol and LH concentrations every 3 h until ovulation. Estrus was shorter in MAT than CON ewes (24.7 ± 1.5 h vs. 30.4 ± 1.5 h, respectively; P=0.02); the proportion of animals that ovulated before the end of estrus was greater in CON ewes: (9/10 vs. 3/10, P=0.009). The area under the LH curve (AUC) was greater in MAT than CON ewes (36.1 ± 3.5 ng.h-1.mL-1 vs 24.9 ± 3.5 ng.h-1.mL-1 P=0.03). However, MAT ewes had a lower 17β-estradiol AUC than CON ewes (41.0 ± 4.9 pg.h-1.mL-1 vs 59.4 ± 4.9 pg.h-1.mL-1 P=0.01). Mating reduced the estrous length, induced a greater secretion of LH but less total 17β-estradiol secreted and, additionally, ovulation occurred more frequently after the end of estrus in mated ewes.

Factors affecting pregnancy rates for goat embryos recovered and transferred by transcervical route

Abstract This study evaluated the factors affecting non-surgical embryo transfer (NSET) efficiency in goats. Donor goats (n = 10) were superovulated, mated and embryos were collected by non-surgical embryo recovery 7 d after estrous onset. A total of 28 pluriparous recipient goats were subjected to short-term progestagen-based estrous induction protocol with equine chorionic gonadotropin. They received 36 fresh embryos as single (n = 20) or in pairs (n = 8) by NSET 6 to 7 d after estrous onset, ipsilateral to the corpora lutea (CL). Pregnancy rate was affected (P 0.05) by the uterine horn, number of CL (1 to 3), lactational status and number of embryos transferred per recipient goats. Both overall pregnancy and kidding rates were 32.1% and 13 kids were born, representing an embryo survival rate of 36.1%. Goat embryo transfer programs can be successfully performed by using non-surgical techniques, achieving satisfactory embryonic survival rates.

Repeated trans-cervical embryo recoveries in Santa inês ewes subjected to short- or long-term superovulatory treatment regimens

Outcomes of short- (6.5 days) and long-term (14.5 days) estrous synchronization for 6.5 d (G-6.5d) or 14.5 d (G-14.5d) and followed by the 4-day or 3-day declining-dose follicle-stimulating hormone superovulatory regimen, respectively, were compared using 16 estrous-cycling Santa Inês ewes. Non-surgical embryo recovery (NSER) procedures were performed 60 d apart starting 6 or 7 d after the onset of estrus; an i.m. injection of estradiol benzoate and of d-cloprostenol at 16 h was followed by an i.v. oxytocin injection administered 20 min before NSER. There was a longer (P < 0.05) period before estrous onset in ewes during the second (September) compared with the first study replicate (July) by approximately 14 h. The NSER could be performed in 11 of 15 ewes that were in estrus, with an average of three viable-embryos/donor and the mean duration of the procedure being 29 min. There were no differences in superovulatory responses between the two groups of ewes, but there were only degenerated embryos in ewes of the G-6.5d group. In summary: i. the duration of progestin-priming and of multiple-dose pFSH treatment had a limited effect on superovulatory responses in estrous-cycling Santa Inês ewes; ii. NSER is a safe and repeatable method of embryo collection in ewes subsequent to superovulation; and iii. duration of the superovulatory treatment regimen may alter the effects of endogenous steroids on oocyte/embryo quality in ewes.

On-farm lambing outcomes after transfer of vitrified and slow frozen embryos

The aim of the present study was to determine the most suitable embryonic stage and embryo freezing technique for commercial implementation of frozen embryo trading by small-scale sheep producers. There was a 2 × 2 factorial design utilized for conducting the study consisting of two embryo stages (2−8 cells or morula/blastocyst) and two cryopreservation protocols (vitrification or slow-freezing). For the in vivo produced embryos, there were treatments of crossbred donor ewes to induce superovulation. Embryos were recovered surgically on either Day 2 or 5.5 after estrous onset. The embryos were cryopreserved using either a vitrification or slow-freezing method before there was transfer to recipients. Ovarian response, embryo survival and lambing outcomes were analyzed. There were no differences in number of recovered and fertilized embryos at the two embryonic developmental stages. There were no effects of embryonic stages and cryopreservation methods on pregnancy rate, twinning rate, fetal birth weights and lamb weight at 1 month of age. When there was use of vitrified embryos for transfers, there was a greater lamb weight at 2 months of age (8.38 ± 0.20 compared with 7.78 ± 0.21 kg; P = 0.044) than when there was transfer of embryos cryopreserved using slow freezing procedures. Considering economic and practical benefits to small-scale sheep farms, morula/blastocyst stage-embryo collection and transfer into the uterus is more efficacious than transferring 2−8 cells embryos into the oviduct. Results of this study may contribute to the genetic improvement in the flocks of small-scale sheep producers.

Optimal timing of artificial insemination and changes in vaginal mucous characteristics relative to the onset of standing estrus in Beetal goats

The current study was conducted to determine the optimal timing of artificial insemination and vaginal mucous characteristics relative to the onset of estrus in goats. Does (n = 257) were estrous synchronized using hormonal treatments. Intracervical inseminations with fresh semen were performed at 0, 12, 24 and 36 h after the onset of estrus. Characteristics of vaginal mucus (i.e., color, consistency, and volume) were observed and graded at the time of AI to calculate cumulative mucous score. The vaginal electrical resistance (VER) was recorded (Draminski® detector) at the time of AI. Pregnancy rate was less (P < 0.05) when inseminations occurred at 0 h (28.6%) compared with 12 (58.3%) and 24 h (56.4%) after the onset of estrus; however, pregnancy rate at 36 h (54.5%) did not differ (P> 0.05) compared with inseminations at 0, 12 or 24 h after estrous onset. Relative odds for pregnancy rate at 12, 24 and 36 h were 5.24, 5.20 and 3.29 times greater compared with 0 h. Cumulative mucous score varied (P < 0.05) relative to the onset of estrus and correlated well (P < 0.05) with the color and consistency than volume of the mucus. The VER was less (P < 0.05) at 12 than 0 and 36 h after estrous onset. In conclusion, goats can be inseminated between 12–36 h after the onset of estrus; however, the chances of pregnancy are greater with inseminations at the 12 or 24 h time periods.

Effects of intravaginal devices containing different dosages of medroxyprogesterone acetate for the control of the estrous cycle in gilts

This aim of this study was to investigate the effectiveness of intravaginal devices (IVDs), containing medroxyprogesterone acetate (MPA), for controlling the estrous cycle in pubertal gilts. Gilts were assigned to four treatments: Control (no IVD); IVD containing 100 (IVD100), 200 (IVD200) or 400 mg (IVD400) of MPA. The IVDs were inserted on day 12 of the estrous cycle and maintained intra-vaginally for 14 days. The percentage of gilts in estrus, interval between IVD removal and estrous onset, adjusted farrowing rate (AFR), total number of piglets born (TPB), follicle size and serum progesterone (P4) were recorded. None of the gilts expressed estrus during the IVD treatment period. All gilts of the control group expressed estrus (15/15; 100%) which was greater (P = 0.03) than all IVD-treated gilts (33/44; 75%); however, there were no treatment differences (P = 0.09). The interval between IVD removal and estrous onset was shorter for IVD100 (3.8 ± 0.6 d) compared to IVD400 (5.3 ± 0.6 d; P = 0.05). The IVD400-treated gilts had smaller follicles than the IVD100-treated gilts (P = 0.05). The P4 concentrations were similar among treated groups (P = 0.99). The AFR did not differ among treatment groups (P = 0.37); however, the control group had a greater TPB than the other treatment groups (P = 0.04). The gilts treated with IVDs had longer interval to estrous expression. The most effective dosage was 400 mg of MPA, considering both the minimal follicular growth during the IVD treatment period and the lesser numbers of persistent follicles.

Effects of d-cloprostenol administrations with 7.5 and 11.5-day intervals between administrations on pregnancy rates after artificial insemination in estrous cyclic dairy goats

This study was conducted to evaluate effects of two administrations of d-cloprostenol at different intervals to synchronize the time of estrus and ovulation among estrous cyclic goats. In Experiment 1, 32 does were treated with 30 μg d-cloprostenol at 7.5 (T7.5, n = 16) or 11.5-day (T11.5, n = 16) intervals. In Experiment 2, the same treatments were administered and there was AI of the does (T7.5, n = 40 and T11.5, n = 38). In Experiment 1, ultrasonic assessments of ovaries were conducted at the time of the second administration of d-cloprostenol, every 12 h until detection of ovulation, and 7 days after estrous onset to detect the corpora lutea, as well as for pregnancy diagnosis 40 days after AI. In Experiment 1, the estrous response (90.6%, 29/32) was similar (P > 0.05) in both groups. Diameter of the largest follicle at the time of administration of the second dose was larger (P = 0.01) in the T7.5 than T11.5 group (7.0 compared with 5.7 mm), while the values for ovarian variables were similar (P > 0.05). In Experiment 2, the greatest (P < 0.001) synchrony in timing of initiation of estrus in does (T7.5 = 83.3% and T11.5 = 50.0%) occurred after the second day (36–48 h). The pregnancy rate tended (P = 0.0836) to be greater for does in the T7.5 (71.4%, 40/56) than T11.5 (55.6%, 30/54) group. With use of both protocols, there were acceptable estrous synchronization and pregnancy rates in estrous cyclic dairy goats.

Different estrus induction protocols and fixed time artificial insemination during the anoestrous period in non-lactating Kivircik ewes

The efficiency of medroxyprogesterone acetate (MAP) sponges or norgestomet ear implants (half or entire) for synchronizing and inducing the estrous cycle in non-lactating Kivircik ewes was investigated during the natural non-breeding period. Ewes were treated for 11 days either with 60 mg MAP sponges (group 1, n=27) or with 1.5 mg norgestomet (group 2, n=25) or with 3 mg norgestomet (group 3, n=27) ear implants. In addition, each ewe received an intramuscular injection of 500 IU of equine chorionic gonadotropin (eCG) and 125 μg cloprostenol (PGF2α), 48 h prior to progestagen removal. Double Cervical Artificial Insemination (AI) with diluted fresh semen was performed at a fixed time (36 and 48 h) following progestagen withdrawal. Mean values for estrous detection rates at the first 12 ± 6 h and within 72 h, the time from progestagen removal to the onset of estrous, the duration of the induced estrous and pregnancy rate were found to be 46.8%, 86.1%, 26.1 ± 7.3 h, 27.0 ± 10.7 h and 27.8%, respectively. There were significant differences between groups 2 and 3 in the time of induced estrous onset (P&lt;0.05). These results indicate that, each of the three protocols was equally efficient in inducing and synchronizing estrus in non-lactating Kivircik ewes during the natural non-breeding period.

Use of two doses of cloprostenol in different intervals for estrus synchronization in hair sheep under tropical conditions.

This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes received two doses of 120μg cloprostenol at 7 (G 7days), 9 (G 9days), or 11.5 (G 11.5days) days apart. Ultrasound assessments were performed from the first and second cloprostenol administration for 5days or ovulation detection. Estrus signs were checked by a teaser male. Plasma progesterone concentration was measured before each cloprostenol dose. In Experiment 2, 95 ewes were allocated into the same treatments and after the second dose, ewes in estrus were mated. At 30days after breeding, pregnancy diagnosis was conducted and prolificacy was evaluated at lambing. In Experiment 1, at the first cloprostenol administration, 50% of ewes had an active CL and all showed estrus. At the second administration, 66.7% of ewes had an active CL and one did not present estrus. There was no difference (P>0.05) after the second dose for as follows: overall estrous response (90%), interval from cloprostenol administration to estrous onset (42.0±4.9h), estrus duration (31.5±2.1h), ovulation rate (100.0%), and number of ovulations (1.5±0.3). In Experiment 2, both pregnancy and prolificacy rates were similar (P>0.05) for G 7days (73.3; 145%), G 9days (75.9; 125%), or G 11.5days (75.9; 145%), leading to an overall pregnancy rate of 75.0% (66/88) and prolificacy rate of 137%. Therefore, the three treatments proposed were able to promote high pregnancy and prolificacy rates in crossbred ewes.

Role of Male effect on Reproductive Efficiency of Nulliparous Santa Inês and Morada Nova ewes raised in Different Regions

Background: The male effect is an attractive strategy to increase herd production by concentrating mating events and deliveries and further allowing the adoption of genetic improvement programs. It holds similar efficiency to those chemically based estrous synchronization methods, but has the advantage of being a natural method. The work was aimed to evaluate the influence of male effect on estrous induction and synchronization, pregnancy and prolificacy of nulliparous Santa Inês and Morada Nova ewes raised in Semiarid and Zona da Mata regions of Pernambuco state.Materials, Methods &amp; Results: Santa Inês (n = 80) and Morada Nova (n = 80) females, with age from 11 to 12 months, after being evaluated and selected, were identified with plastic ear tags, weighted and maintained isolated from males, during 30 days before experiment onset, without any physical, visual, olfactive and auditive contact. Estrous events were observed twice a day (6:00 and 16:00 h) by trained personnel, during a breeding season of 60 days, and estrous were considered synchronized when detected, within first five days of breeding season. Rams of Santa Inês (n = 2) and Morada Nova (n = 2) breeds were selected based upon reproductive capacity by an andrology exam, and were marked on the externum bone region with a wax and ink (4:1) mixture, and were marked in female lots in order to identify females in estrous. After ten days of breeding season onset, rams were again marked with the same wax and ink mixture, but with a different ink color. Pregnancy diagnosis was performed on day 30 by ultrasonography and confirmed on day 60 after the last mating. The statistical analysis was performed using SAS, version 8. Differences of 5% (P &lt; 0.05) or lower were considered significant. The results show that estrous synchronization in the semiarid region in both breeds was detected in 10% of females. The total pregnancy on first service was 45.00% and on second was 52.94%, with 85.18% of singleton and 14.81% twin deliveries, with prolificacy de 1.15 ± 0.38. In the Zona da Mata region 10% Santa Inês and 15% Morada Nova females had synchronized estrous (P &gt; 0.05). The total pregnancy was 42.50% on first, 64.70% on second service and total delivery was 86.20% singletons, 12.06% twins and 3.33% triples with prolificacy of 1.15 ± 0.31. On both Semiarid and Zona da Mata regions, the majority of estrous events occurred between the11th and 15th day of the breeding season for Santa Inês ewes and between 6th and 10th day for Morada Nova ewes.Discussion: The occurrence of estrous, for both breeds, in both regions, were detected throughout the breeding seasons, despite most estrous detections were within the initial fifteen days, which normally happens with cycling pluriparous females, in disagreement with findings in the literature that young females display lower reproductive performance on the first breeding season. However, the sexual inexperience of young females is not equivalent to lack of male receptivity, since then, could not be responsible for late estrous onset in a breeding season of young females. In agreement with this statement, and based on the data described here, it has been described that young ewes display estrous within the initial 18 days of breeding season onset. The estrous dispersion in biostimulation programs is normally due to female cyclicity, a physiological condition that lowers the sensibility to estradiol negative feedback response, but are still responsible to the presence of males.

Vaginal mucus from ewes treated with progestogen sponges affects quality of ram spermatozoa

The use of intravaginal sponges (IS) to synchronize estrous onset in ewes provokes vaginitis, an increase in the vaginal bacterial load, and growth of bacterial species that are not present during spontaneous estrous behavior. The objective of the study was to compare the functional sperm parameters after incubating it with mucus collected from the vagina of ewes during spontaneous estrus or estrous synchronized with IS. Pooled spermatozoa were co-incubated with: (1) vaginal mucus collected from ewes in spontaneous estrus; (2) vaginal mucus collected from ewes in estrus pretreated with progestogen-impregnated IS; (3) synthetic mucus; and (4) medium without mucus as a control group. Sperm samples were evaluated after incubating it for 30 and 90 minutes. The number of colony-forming units (CFUs/mL), pH, and osmolality were greater in the mucus collected from ewes treated with IS than from those untreated (P = 0.046; P < 0.0001, and P < 0.0001, respectively). The percentage of sperm with progressive motility was lower after incubation with vaginal mucus collected from estrous ewes treated with IS than in the other three treatments both, 30 and 90 minutes after incubation (P = 0.0009 and P < 0.0001, respectively). The sample incubated for 30 minutes with mucus from ewes treated with IS had a lower percentage of sperm with intact plasma membrane than all the other treatments (P < 0.0001). The percentage of sperm with functional membrane was significantly lower in the sample incubated for 30 minutes with vaginal mucus from ewes treated with IS than in the other three treatments (P < 0.0001). After 90 minutes, the percentage was still lower than that in the sample collected from ewes during their spontaneous estrus (P = 0.0005). The lowest percentages of sperm with acrosome damage were observed in sperm incubated with mucus collected from sheep in spontaneous estrus for 30 and 90 minutes (P < 0.0001 and P = 0.008, respectively). The percentage of apoptotic spermatozoa was greater in samples incubated during 30 minutes with vaginal mucus collected from ewes treated with IS than in the other three groups (P = 0.0005). The functionality and the viability of ram sperm is negatively affected by the cervical mucus of ewes pretreated with progestagen-impregnated IS used in estrous synchronization treatments. This may partially explain the decrease in conception rate obtained with treatments with IS.

Estrous behavior, ovulatory follicle dynamics, and corpus luteum size in Creole cows after spontaneous or prostaglandin F2α-induced estrous

Background: evaluation of reproductive behavior in Creole cows is important to determine several parameters, such as fertility, that show the physiologic reproductive mechanisms under different conditions. Therefore, the sequence of events such as ovulation and the subsequent formation of a corpus luteum need tobe considered to establish genetic improvement programs under synchronized or naturally-occurring estrous conditions. Objective: to evaluate the ovarian and behavioral estrous characteristics before, during and after prostaglandin F2α-induced or naturally occurring estrous in Creole cows. Methods: thirty Creole cows were subjected to estrous synchronization with PGF2α and observed continuously over five days to determine estrous onset and duration. Seventeen days after synchronized estrous detection, cows were observed during seven d to detect the naturally-occurring estrous and its duration. After the onset of both types of estrous the ovaries of each cow were ultrasounded every 8 h to determine diameter of the preovulatory follicle at deviation and its maximum diameter prior to ovulation, as well as its growth rate, time to ovulation and maximum diameter of the later corpus luteum. Results: time of appearance and duration of synchronized and spontaneous estrous were similar (p&gt;0.1). Diameters of the dominant follicle at deviation and prior to ovulation were similar in both types of estrous. Nevertheless, growth rate (mm/d) of the preovulatory follicle was higher (p &lt; 0.05) in synchronized estrous. However, time from onset of synchronized estrous to ovulation was longer (p &lt; 0.01).Diameter of corpus luteum 10 d after ovulation was similar in both types of estrous. Results indicate that growth rate of follicle and time from synchronized or spontaneous estrous to ovulation must be considered for estrous cycle manipulation and artificial insemination of Creole cows. Conclusion: a higher proportion of Creole cows show heat during nighttime, growth rate of ovulatory follicle is higher during synchronized estrous, and time from onset of synchronized estrous to ovulation is longer, when compared with spontaneous estrous.

Fetal adrenal cortex development with maternal serum Cortisol profiles in Relation to Estrous Induction, Laparoscopical Insemination in Iraqi goats out breeding season

The objectives of this research were to determine the serum cortisol profiles and their temporal interrelationship during progesterone treatment, induced estrous, laproscopical insemination and pregnancy (antepartum) period in goat, with histological fetal adrenal cortex development.Thefirst part of the experiment included studying Hundred and sixty goat fetuses of different Crown Rump Length (CRL) were collected from slaughter house. The adrenal glands in the goat fetus displayed signs of cytological differentiation around the second half of intrauterine life, 20cm/CRL about 90 days old until full term. From histological observation and physical measurements the present study recorded that the adrenal cortex grow faster from 25 cm/CRL(100 days)to term The majority of this growth take place due to hyperplasia in the adrenal cortex, zone fasciculate. This second part of the experiment condeucted on 16 female local goats aged 2-4yers,weight 30-45Kg. Estrus was inducted by application of impregnated sponges content 20 mg fluorogestone Acetate(FGA) for 13 days and an IM injection of 500 IU Pregnant Mare Serum gonadotropin (PMSG) 24hrs before sponges withdrawal Within 24-36 hrs of estrous sings onset, each doe was inseminated laparoscopically with 1ml of fresh diluted semen contain at least 100 million active fresh sperms directly into the uterine body. Maternal blood samples were collected at day 10th of progesterone treatment, 24hrs after laparoscpical insemination and monthly during pregnancy. The results revealed that all does showed signs of estrous (100%) after 24-72 hrs with a mean time of 46.9±4.90 hrs after sponges removal. Estrous length was 37.1 +1.91 hrs. Pregnancy diagnosis was performed by ultrasonography examination at 30th, 60th and 90th days post insemination. Pregnancy was found in 13 does (81.22%), 3 of them had twin kids (23.01%). Serum cortisol levels shows the highest level during the 4th and 5th months of gestation periods compared to that of the others periods of this study with overall average 78.93+2.96 nmol/L, respectively.

Effect of sun flower oil addition (Helianthus annuus) in diet on nutrient intake, growth performance and characteristics of estrous of pre-mating Garut sheep

Nutritional status of ewes at pre-breeding phase is critical for good reproductive process. Thirty-two ewes Garut sheep (initial body weight 22.5±2.21 kg) were used in a completely randomized design to evaluate the effects of addition of sunflower oil in the diet on nutrient intake, growth performance and characteristics of estrous of pre-mating garut sheep. Ewes were fed grass and supplemented with one of four isonitrogenous high concentrate diets containing four levels of sunflower oil; they were (M0) no addition of sunflower oil; (M1) 2% sunflower oil; (M2) 4% sunflower oil and (M3) 6% sunflower oil addition. Results showed that the addition significantly reduced dry matter intake (p < 0.05), highly significantly reduce crude protein, Ca and P intake (p < 0.01), higly significant increased ether extract intake (p < 0.01) and significantly increased long of estrous (p < 0.05). There was no difference in crude fiber intake, TDN intake, body weight gain, length of estrous onset and response of estrous for ewes fed the four experimental diets. Response on estrous of treatments M0, M1, M2 and M3 were 62.50; 50.00; 75,00 and 62.5% respectively. It is concluded that the addition of sunflower oil up to 6% in the pre-mating ration affects the nutrient intake without interferering the performance, and it tends to improve the charachteristic estrous of Garut ewes. Key Words : Nutrient Intake , Estrous, Garut Sheep, Performance, Sunflower Oil

Reproductive parameters of dairy goats submitted to estrus synchronization with prostaglandin F2α associated or not to hCG at estrous onset

The objective of this study was to evaluate the efficiency of two doses of PGF associated or not to hCG on the associated reproductive parameters in dairy goats. A total of 29 goats received two doses of 30µg d-cloprostenol latero-vulvar at a 10 day intervals (Day 1 and Day 10). The does were allocated according to body weight and body condition score into two treatments, to receive hCG (250IU) or saline at estrus onset. After the second dose of PGF, estrus was monitored and ultrasound exams were performed twice daily. All does were inseminated 16h after estrus onset. Blood collection was performed every day for progesterone assay. The use of hCG at estrus onset did not affect any studied parameter and therefore the data were pooled. Estrous response rate was similar (P&gt;0.05) after the first (75.9%, 22/29) and the second dose of PGF (79.3%, 23/29). The interval between the administration of PGF and estrus onset was greater (P&lt;0.05) after Day 1 (75.8±53.9h) than Day 10 (47.7±10.1 h). Estrus duration was superior (P &lt; 0.05) after Day 1 (35.4±15.9h) to Day 10 (26.8±15.0h). Ovulation rate was 79.3% (23/29) after the second dose of PGF. No differences (P&gt;0.05) between both experimental groups were detected in the following parameters, averaging: the interval from the second dose administration to the ovulation (86.6±11.4h), interval from estrus to ovulation (39.9±12.3 h), diameter of largest follicle (7.2±1.4) and number of ovulations (1.8±0.6). At Day 1, 52.4% (11/21) of does presented progesterone concentrations &lt;1ng/mL. At Day 10, 100% of the animals presented concentrations &gt;1ng/mL. The results of the present study indicate that estrus can be efficiently synchronized in dairy goats with the use of two doses of PGF at a 10 day interval. Further research should be done evaluating hCG use in different doses or moments of administration.