Estrus Quality of Garut Sheep after Estrus Synchronization using Prostaglandin, Progesterone, and Their Combination

Abstract. Hafizuddin, Husnurrizal, Thasmi CN, Herrialfian, Salsabil NL, Siregar TN, Sutriana A. 2024. Estrous characteristics and steroid concentrations in Aceh cows (Bos indicus) after estrus synchronization using prostaglandin F2a. Biodiversitas 25: 322-328. This study aims to determine the estrous characteristics and steroid concentrations during estrus in Aceh cattle after estrus synchronization using prostaglandin F2a. This study involved 9 Aceh cows with good reproductive status, not pregnant, and has shown at least 2 regular cycles, which were divided into 3 treatment groups. The first group (GI) received a single injection treatment, the second group (G2) received a double injection treatment with an interval of 10 days, and the third group (G3) was also treatment double injection with an interval of 12 days. Symptoms and responses to estrus were reported descriptively, and the data collected on onset, intensity, and duration of estrus were analyzed using one-way analysis of variance followed by Duncan's test. The results showed that estrus symptoms were almost similar and estrus response was 100% in all three treatment groups. The onset of estrus in G1, G2, and G3 did not differ significantly (P>0.05) with values of 68.00±18.33, 60.00±0.00, and 72.00±24.00 hours, respectively. The intensity of estrus in G1, G2, and G3 showed significant differences (P<0.05) with scores of 3.00±0.00, 5.00±0.00 and 4.33±1.15, respectively. The duration of estrus showed no significant difference in G1, G2, and G3 (P>0.05) with durations of 32.00±18.33, 72.00±0.00, and 52.00±38.57 hours, respectively. The concentrations of estradiol and progesterone obtained also showed no significant differences (P>0.05) in G1, G2, and G3, with respective concentrations of 91.67±24.77, 132.00±23.15, 89.47±24.19 pg/mL and 0.98±0.59, 0.86±0.18, 1.00±0.17 ng/mL. In conclusion, estrus synchronization with PGF2a single injection and double injection in Aceh cattle was found to have 100% estrus response. However, PGF2a with double injection showed higher estrus intensity compared to single injection. In Aceh cows, the recommended protocol for estrus synchronization using PGF2a is double injection.

For evaluating different methods of long term estrous synchronization followed by fixed time artificial insemination and to select the most efficient method, during the breeding season 160 Persian downy does were equally allocated to groups (n = 20/group). Estrus was synchronized using controlled internal drug release devices alone (CIDR) or with equine chorionic gonadotropin (CIDR-eCG), intravaginal sponge impregnated with 45 mg fluorgestone acetate alone (Sponge) or with eCG (Sponge-eCG), subcutaneous auricular implant of 2 mg norgestomet alone (Implant) or with eCG (Implant-eCG) or two intramuscular injections of 10 mg prostaglandin F2α 10 days apart alone (PGF) or accompany with eCG (PGF-eCG). The dose of eCG was 400 IU and injected intramuscularlly at the end of treatments. Heat detection and fixed time artificial insemination were done 12 and 48 hours after the end of the treatments, respectively. The estrus was detected in 94.7-100% of the does who received different forms of progestagens and estrus response was not affected by eCG. Estrus response in PGF-based groups was significantly lower (P < 0.05) than progesterone-based groups. Injection of eCG did not affect fertility, fecundity and prolificacy rates in CIDR, Sponge and Implant groups. It also did not affect parturition rate in implant group. Finally, with respect to estrus response, fertility rate, costs and the simplicity of methods it can be concluded that the use of intravaginal CIDR for 16 days without administration of eCG may be a more efficient method for estrus synchronization in fixed-time artificial insemination programs in Persian downy does.

This study aims to determine the effect of using multivitamins in different estrus synchronization hormone protocols on estrus response, estrus onset, estrus duration, estrus intensity, and pregnancy rate in swamp buffalo. This study used 30 post-partum adult buffalo, with three estrus synchronization methods treated: 1. Conventional plus Prostaglandin F2 α (PGF2α-PGF2α + multivitamin)-AI; 2. Co-synch plus Gonadotropin-releasing hormone (GnRH-PGF2α + multivitamin)-AI; 3. Combination of hormone plus (Estrogen-Progesterone-PGF2α + multivitamin)-AI. Research variables include estrus response, estrus onset, estrus duration, estrus intensity, and pregnancy rate. Data were analyzed using the chi-square test using the Statistical Package for the Social Sciences 23.0 program. The results showed that the use of multivitamins in different estrus synchronization hormone protocols resulted in an estrous response reaching 100%. The onset of estrus in the three treatments [Treatment-1 (T1); Treatment-2 (T2); Treatment-3 (T3)] was 25.8; 27.6; 23.9 h, estrus duration: 21.0; 21.6; 21.92 h, estrus intensity: 25.8; 27.6; 32.6 h, and the pregnancy rate for buffalo reaches 80%. Based on the results of this study, the use of multivitamins in different estrus synchronization hormone protocols is effective in optimizing the swamp buffalo's estrus response; the estrus duration is longer, the estrus onset is faster, and the estrus intensity is higher. It can even optimize the increase in swamp buffalo pregnancy rates.

Summary The objective of this study was to investigate the efficacy of used controlled internal drug release devices (CIDR-G) on estrous synchronization in ewes. This investigation was conducted in 58 fat-tailed ewes during the non-breeding season. Ewes were divided in to four groups. In Group I, CIDR-G devices were inserted to vagina for 12 d (CIDR group). In Group II, previously used CIDR-G devices were inserted into the vagina for 12 d (U-CIDR). After the intravaginal devices had been removed 500 IU equine chorionic gonadotropin (eCG) was injected intramuscularly (i.m.) into ewes of the CIDR and U-CIDR groups. Ewes in Group III (eCG group), 500 IU eCG was injected im. Ewes in Group IV, served as control and received an injection of 3 mL 0.9% NaCl (C Group). None of the control ewes expressed estrus. It was found that, 13/15 (86.67%), 10/15 (66.67%) and 1/13 (7.69%) ewes expressed estrus in CIDR, U-CIDR and eCG groups, respectively. The pregnancy rates in the CIDR, U-CIDR and eCG groups were 8/15 (53.33%), 9/15 (60%) and 1/13 (7.69%) at first breeding, respectively. The interval from eCG application to onset of estrus was 42.6±1.01, 40.13±1.35 and 74 h in the CIDR, U-CIDR and eCG groups, respectively. Average progesterone (P4) levels during P4 treatment were 3.28±0.28 and 2.62±0.14 ng/ml in the CIDR and U-CIDR groups, respectively. It is concluded that, CIDR-G that have been previously used for 12 d could be used for the synchroniation of estrus in ewes during non-breeding season.

The study evaluated the effect of duration of progestagen treatment and breed on response to oestrous synchronisation and pregnancy rate following AI in 47 Boer and 27 unimproved indigenous goats. Each breed was subdivided into two groups, based on the duration of progestagen treatment. In the long-term progestagen treatment, controlled internal drug release dispensers (CIDRs) were inserted for 16 days, while in the short-term progestagen treatment, CIDRs were inserted for 9 days. Oestrous detection was performed for a period of 72 h, starting at CIDRs withdrawal. AI was performed 48 h following CIDRs removal with raw or frozen/thawed semen. Pregnancy diagnosis was performed at day 35 following AI. Boer goat exhibited a significantly (p <0.05) higher oestrous response (100%) than unimproved indigenous goats (88.9%). Breed had no effect on the onset of oestrus. Boer goat does recorded a longer duration of the induced oestrous period, compared to the unimproved indigenous goats. No significant difference was observed between short or long-term progestagen, with respect to the oestrous response, onset and duration of the induced oestrous period. The pregnancy rate was not affected by breed and semen cryopreservation. However, long-term progestagen treatment drastically reduced pregnancy rate. In conclusion, breed had an effect on oestrous response and the duration of induced oestrous period. The interaction of breed and duration of progestagen treatment had no effect on response to oestrus and onset of oestrus. The pregnancy rates of the current study were generally low and were affected by the duration of progestagen treatment.

Oestrous response and characterization of the ovulatory wave following oestrous synchronization using PGF2α alone or combined with GnRH in ewes

The effects of different estrus synchronization techniques on follicular development and estrus response were studied in 81 nulliparous Boer does. The does were divided into nine groups. Eight of the nine groups were synchronized with prostaglandin F2-alpha (PGF(2α)) or flugestone acetate (FGA) or their combinations, and the ninth group was a control group. In addition to the above combinations, four of the eight synchronized groups were given 5 mg follicle-stimulating hormone (FSH) and the remaining four groups were administered 300 IU equine chorionic gonadotrophin (eCG). Posttreatment follicular development was monitored until ovulation occurred using a real-time B-mode ultrasound scanner (Aloka, 500 SSD, Japan), with a 7.5-MHz transrectal linear probe. All the does from the synchronized groups that were given eCG exhibited oestrus while only 88.9% of the does synchronized with FSH showed estrus. The estrus response was observed to be the least among the does synchronized with PGF(2α) + FSH (33.3%) combination followed closely by the FGA + FSH (42.9%) combinations. It was observed that the combinations of FGA + PGF(2α) + FSH resulted in increased percentage of estrus response, duration of estrus, and ovulation. The number of follicles was higher (P < 0.05) in FSH-synchronized groups than the eCG-synchronized groups. It was concluded that the best estrus synchronization protocol in goats is the FGA + eCG with or without PGF(2α). However, the PGF(2α) + FGA + FSH method of estrus synchronization is the most promising combination for further development as a better alternative to estrus synchronization with eCG in does.

Indonesia has significant potential in the beef and dairy cattle sectors but faces challenges in improving the genetic quality of livestock. Embryo Transfer (ET) is a biotechnological approach that can enhance genetic quality and livestock productivity. This study aims to examine and analyze the factors affecting the success rate of pregnancies in FH dairy cattle as recipients of embryo transfer at Balai Embrio Ternak (BET) Cipelang. Secondary data from BET Cipelang (2017-2023) were used, including variables such as embryo quality, transfer methods, recipient age, estrus synchronization methods, and embryo donor breeds. The results showed that good embryo quality (24.55%) and fresh transfer methods (35.19%) significantly increased pregnancy success (p 0.05). Synchronization methods using PGF2α and a combination of Progesterone + PGF2α increased the chances of pregnancy by 3.60 and 3.89 times, respectively, compared to natural estrus. Although not statistically significant, recipient age groups of 3-5 years and 6-9 years had higher pregnancy success rates compared to the 10-12 years age group. The donor breed of embryos did not show a significant effect on pregnancy rates. Therefore, this study concludes that good embryo quality and fresh transfer methods significantly increase the pregnancy success rate in FH dairy cattle at BET Cipelang. The factors influencing pregnancy rates include embryo quality, transfer methods, recipient age, estrus synchronization methods, and donor breed, with embryo quality and fresh transfer methods having the greatest impact. To improve pregnancy rates, it is recommended to select high-quality embryos, use fresh transfer methods, and implement effective estrus synchronization protocols, such as PGF2α injection or a combination of Progesterone + PGF2α. Further research involving various recipient cattle breeds and genetic and environmental factors is also advised.

One of the biotechnology reproductive used is estrus synchronization. This study determined the body’s physiological, estradiol level, and ovarian and follicle diameter in Peranakan Ongole (PO) cow estrus synchronization using modified progesterone-PGF2α and double injection of PGF2α. This study used 10 PO cows which were divided into two groups. Group 1, cows were given a modified intravaginal sponge containing 250 mg progesterone/sponge for 6 days, followed by intramuscularly injection of PGF2ɑ 25 mg/cow on day sixth. Appearance of estrus was observed on day 7th -9th. Group 2, cows were given a double injection 25 mg/cow of PGF2ɑ intramuscularly at 14-day intervals, then estrus was observed on day 15th -17th. The vaginal temperature was checked using a thermometer, the respiratory frequency was checked by inspection of thorax movements, and the pulse rate was checked by palpation of the coccygeal artery. Ovarian and Graafian follicle diameters were examined using ultrasonography. The data were analyzed using either T-Test or descriptive test. The results showed that in cows that were synchronized to estrus using combination of modified progesterone-PGF2ɑ and double injection of PGF2ɑ, the vaginal temperature, pulse rate, and respiration frequency were 36.9±0.98 and 37.34±0.83, 57.60±12.52 and 74.80±26.59, 30.40±10.43 and 20.00±2.83 respectively. There was no significant difference in ovarian and follicle diameter (P>0.05). The conclusion was the results of body physiology were in normal conditions but still below the average of cows undergoing estrus, and there were no significant differences in ovarian and Graafian follicle diameters.

The study was conducted to determine the estrus response to the applying of prostaglandin nanoparticles (PNp) in two different estrous synchronization protocols. The estrus synchronization occurred in the Majalengka Regency in different years at the same location. The first study (study 1), estrus synchronization was carried out using a single PNp injection protocol, which was preceded by corpus luteum (CL) selection (21 cows). The second study (study 2), double PNp injections were carried out at day-0 and day-11 without prior CL selection (23 cows). The observation of estrus: onset of estrus and estrus quality (score 0-3) were observed 1-5 days after the PNp injection. Results of the study showed that 100% of the cattle were in estrus 2-3 days after the injection of PNp (study 1). The study 2, the estrus response appeared 2-3 days after the PNp injection: 17.35% showed an estrus response after the first PNp injection, 78.26% showed an estrus response at the second PNp injection, and 4.35% showed no estrus response. The pregnancy rate after estrus synchronization is 66.7% and 68.2% for studies 1 and 2. It can be concluded that there is a good response to estrus and pregnancy rate in the application of PNp in both single injections preceding CL selection and double injections with two periods of insemination. Both methods can be applied for estrus synchronization for more savings in PNp hormone administration. The application of that method depends on hormone availability and technician expertise in CL detection.

The aim of this study was to monitor the ovarian response and conception rate following estrous synchronization using CIDR, Ovsynch and double prostaglandin F2α protocols in Egyptian buffalo heifers. A total of 80 cyclic buffalo heifers were divided into four equal groups: CIDR (intravaginal progesterone releasing device, EAZI-BREEDTM CIDR®), Ovsynch (GnRH, PGF2α, GnRH injections), PGF (double PGF2α doses) and control. Timed artificial insemination (TAI) was performed in all heifers. All animals were examined using ultrasound and blood samples were collected for measurement of progesterone. A new follicular wave occurred earlier in the Ovsynch and PGF groups than in the CIDR group (p<0.05). The mean diameter of the ovulatory follicle was smaller in the CIDR group than in the Ovsynch and PGF groups (p<0.05). The ovulation rate was 100% in the CIDR group, 75% in the Ovsynch group and 70% in the PGF group. In the control group a lower pregnancy rate (20%) was determined in than in the CIDR (35%), Ovsynch (40%) and PGF (35%) groups. Progesterone concentrations were numerically higher in pregnant heifers of the CIDR group but the difference was non-significantly compared to the Ovsynch, PGF and control groups (p>0.05). EAZI-BREEDTM CIDR®, Ovsynch-based TAI and PGF protocols were effective in synchronizing oestrus and resulted in nearly similar pregnancy rates in Egyptian buffalo heifers.

Study question Does the number of follicles ≥11mm differ when measured by manual-2D or automated-3D ultrasound and which method predicts the number of oocytes collected more accurately? Summary answer Manual-2D and automated-3D ultrasound find similar numbers of follicles ≥11mm. Automated-3D ultrasound has a higher predictive ability regarding the number of oocytes collected. What is known already Accurate assessment of the size and number of follicles during ovarian stimulation is important to determine the optimum day of triggering final oocyte maturation and subsequent oocyte retrieval, in order to achieve the maximum number of mature oocytes. Moreover, the number of follicles ≥11mm on the day of triggering final oocyte maturation, has been used as a criterion to identify women at risk of Ovarian Hyperstimulation Syndrome. Automated-3D ultrasound follicle size and count measurement has been proposed as a valid alternative to 2D ultrasound measurement, but its predictive ability regarding number of oocytes collected has not been compared. Study design, size, duration Prospective observational cohort study performed between 12/2020 and 07/2021 in a single ART center including 93 women undergoing COS. On the day of triggering final oocyte maturation, 3D-ultrasound (SonoAVC;GE Medical Systems) and traditional 2D-ultrasound were used to assess the number and size of follicles. Participants/materials, setting, methods Patients underwent ovarian stimulation with recombinant-FSH and GnRH antagonists. Triggering of final oocyte maturation was performed when three follicles ≥17mm were present on 2D ultrasound. The number of follicles ≥11mm assessed with manual-2D and automated-3D ultrasound on the day of triggering was compared. Linear regression analysis was performed with dependent variable the number oocytes retrieved and independent variables the number of follicles ≥11mm (2D-ultrasound) as well as the number of follicles ≥11mm (automated-3D ultrasound). Main results and the role of chance The median number of follicles ≥11mm counted via automated-3D [ 10 (IQR: 5.75 – 16)] and the median number of follicles ≥11mm found via manual-2D assessment [10 (IQR: 6.75 – 18)] was similar between the two groups. Τhe median number of oocytes retrieved was 12 (IQR: 6.75 – 18). A high correlation of R = 0.915 was observed between the number of follicles found to be ≥ 11mm via automated-3D and 2D. However, regarding the number of oocytes collected, the predictive ability of automated-3D, was found to be, significantly higher (R2=0.837) than the predictive ability of 2d-ultrasound (R2=0.734) when all follicles ≥11mm were taken into account. These findings suggest that while the number of follicles measured to be ≥ 11mm was similar in both methods, automated 3D-ultrasound measurement offers a higher ability to predict the number of oocytes retrieved, compared to manual 2D-ultrasound measurements. Limitations, reasons for caution The present study compared manual 2D and automated 3D-ultrasound follicle measurements in the general IVF population. Future studies using a larger patient population will be useful to determine any potential differences between the two methods in patients stratified according to ovarian response. Wider implications of the findings Manual 2D and automated 3D-ultrasound assessment provide similar measurements of follicle number and size in patients undergoing IVF but automated-3D measurements offer greater predictive value regarding the number of oocytes collected and can be used effectively to monitor follicular development during ovarian stimulation for IVF. Trial registration number N/A

The research aimed to assess how feeding conditions and the number of the dominant follicles (DF) influence oestrus synchronization in swamp buffaloes. A total of 170 swamp female buffaloes raised in semi-grazing and housekeeping were included in the study. The synchronization used CIDR method and the follicles on the day of CIDR (Controlled Internal Drug Releasing) insert and removal were tracked by sonography. The results indicated that the age of first mating, age at first calving, and caving interval showed no significant differences in the two feeding conditions. The number of follicles at CIDR insertion and removal decreased in semi-grazing, but increased in housekeeping buffaloes. The percentage of buffalo without DF, one DF, and two DFs at CIDR withdrawal did not differ statistically. The percentage of estrus was 100% in both groups. Pregnancy rates were 53.18% in semi- grazing and 52.63% in housekeeping. The onset of oestrus was similar, but the duration of oestrus was longer in the buffaloes without DF than those with one or two DFs. The percentage of pregnant buffaloes in the group without DF was significantly lower than that in the other two groups. In summary, the efficiency of oestrus synchronization did not differ between semi-grazing and housekeeping methods. Buffaloes without DF displayed longer oestrus periods and lower pregnancy rates compared to those with one or two DFs in the ovarian system.

The objective was to evaluate the reproductive performance after oestrus synchronization using controlled internal drug release (CIDR) maintained into the vagina either 7 or 9 days. A controlled randomized block design was performed. Cows (n=255) were blocked by lactation number and days in milk and then randomly divided into 2 groups. In the first group, CIDR was maintained for 7 days (CIDR-7; n=127), and in the second group, CIDR was maintained for 9 days (CIDR-9; n=128). Both groups received Prostaglandin-F2α at CIDR removal. Oestrus response, oestrus onset, oestrus duration, conception rate, and pregnancy at days 28 and 45 were evaluated. Cows were oestrus detected 4 times a day for 120 h after CIDR removal, and only cows in standing oestrus were artificially inseminated between 6 and 12 h after oestrus detection. Oestrus response for both groups was 79.5% and 87.5% for CIDR-7 and CIDR-9, respectively (P=0.09). The oestrus onset (mean ± SD) for the same groups was 56.3±17.2 h and 59.4±17.9 h, respectively (P=0.19). Oestrus duration was 11.3±7.3 h and 11.7±7.8 h for groups CIDR-7 and CIDR-9, respectively (P=0.71). At day 28, the conception rates for the groups CIDR-7 and CIDR-9 days were 51.5% and 45.5% (P=0.39), and the pregnancy rates were 40.9% and 39.8% (P=0.89) for the same groups, respectively. No differences in oestrus performance and fertility in lactating cows’ oestrus synchronized by using CIDR maintained in the vagina either 7 or 9 days were detected.

Estrus synchronization has become a routine reproductive management tool for dairy producers. Reproductive performance has decreased over the last 25 yr on dairy farms, and the lack of estrus detection or inaccurate detection are major reasons for increased numbers of days open for the average cow. Estrus synchronization methods that control both the function of the corpus luteum and the development of follicles with viable oocytes are critical to efficacy. This article reviews some of the synchronization methods used in dairy cattle, especially the recent protocols involving the use of GnRH. Conception and pregnancy rates from a series of studies using the Ovsynch protocol averaged 34.9 and 34.9%, respectively. Conception and pregnancy rates from breeding at detected estrus after PGF2α averaged 37.7 and 19.8%, respectively. Because pregnancy rates are typically below 40%, possible methods for early identification of open cows and resynchronization will be discussed.