11 COMPARISON OF CONTROLLED INTERNAL DRUG-RELEASE INSERT–BASED AND PROGESTERONE-FREE METHODS FOR OVULATION SYNCHRONIZATION AND TIMED ARTIFICIAL INSEMINATION OF GOATS

2016 ◽  
Vol 28 (2) ◽  
pp. 135 ◽  
Author(s):  
A. Llanes ◽  
W. B. Knox ◽  
C. E. Farin
Keyword(s):  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Serum Progesterone ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
The North ◽  
Frozen Semen ◽  
Time Of Breeding ◽  
Agricultural Experiment ◽  
The Mean

A CIDR synchronization program is an important tool for facilitating ovulation synchronization and timed AI (OvSynch-TAI). The objective of this study was to test the efficacy of reusing CIDR for OvSynch-TAI compared with that for a progesterone-free OvSynch-TAI protocol (NCS) or a breed by oestrus detection (ED) control. A total of 87 does were randomised into 1 of 5 treatments: (1) ED (control, n = 18), (2) NCS (n = 18), (3) CIDR6-New (n = 17), (4) CIDR6–1X (n = 17), and (5) CIDR6–2X (n = 17). Does in the ED group received two 15-mg doses of PGF2α at a 10-d interval and were bred 12 h after the onset of oestrus following the second PGF2α injection. The NCS group received 15 mg of PGF2α on Day 0, 50 μg of gonadotropin-releasing hormone on Day 8, 15 mg of PGF2α on Day 15, and 50 μg of gonadotropin-releasing hormone on Day 18, concurrently with TAI. The CIDR groups (new, 1X-used, or 2X-used) received a P4 device for a 6-d period, and 15 mg of PGF2α was administered at CIDR removal. Does were bred 48 h after CIDR removal and were given 50 μg of gonadotropin-releasing hormone at TAI. The CIDR in the CIDR6–1X group were previously in place for 10 days before use, whereas CIDR in the CIDR6–2X group were previously in place for 16 days before use. Reused CIDR were rinsed in a diluted Nolvasan solution, followed by a clean water rinse, allowed to air dry, and stored in a refrigerator until time of use. The experiment was conducted in 2 replicates. Within each replicate, all treatments were scheduled so that does were bred during the same 2-day period, and all does were inseminated with a single dose of frozen semen using a nonsurgical (transcervical) technique. Blood samples were taken daily in all treatment groups to monitor concentrations of serum progesterone until the time of breeding. Pregnancy was determined by ultrasonography at 54 and 85 days of gestation. Data were analysed using GLM procedures of SAS (SAS Institute Inc., Cary, NC, USA). Data for pregnancy rates were analysed with a model that included effects of treatment, replicate, and their interactions. Data for serum progesterone concentrations were analysed with a model that included the effects of treatment, replicate, day, and their interactions. Means were separated by Duncan’s test. Mean progesterone differed (P < 0.001) with treatment (5.3 ± 0.8bc, 3.5 ± 0.8c, 7.0 ± 0.8ab, 7.9 ± 0.8a, 6.2 ± 0.8ab ng mL–1 for ED, NCS, CIDR6-New, CIDR6–1X, and CIDR6–2X, respectively; least squares mean ± standard error of the mean). Pregnancy rates for the ED, NCS, CIDR6-New, CIDR6–1X, and CIDR6–2X treatment groups were 39 ± 11%bc, 22 ± 11%c, 64 ± 12%ab, 77 ± 12%a, and 57 ± 12%ab, respectively. In conclusion, reused CIDR were as effective as new CIDR for attaining satisfactory pregnancy rates. Timed AI using a once-used CIDR was more effective for establishing pregnancy than ED and NCS treatments. The lower pregnancy rates in the ED and NCS groups were associated with lower mean progesterone levels during the Ovsynch treatment period before breeding. This research was supported by the North Carolina Agricultural Experiment Station.

Estrous synchronization and fertility of cross-bred dairy cows using prostaglandin F2α and gonadotropin releasing hormone

2021 ◽  
pp. 171-175
Author(s):  
Abubakr O. Ismail ◽  
◽  
Erneo B. Ochi ◽  
Ambrose S. Jubara ◽  
Bakri Ahmed A/Rahim ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
Estrous Synchronization ◽  
Descriptive Statistical Analysis

A comparative hormonal study of prostaglandin, gonadotropin releasing hormone and their combination was conducted on 30 randomly selected cross-bred dairy cows of SEMEX project for artificial insemination in Hillat Kuku, Khartoum North, Sudan. The study attempts to determine the response of the animals to hormonal induction and synchronization of estrous as well as fertility following fixed time artificial insemination. Three treatment groups of 10 cows each were undertaken. Groups 1, 2 and 3 involved administration of prostaglandin F2α (PGF2α), gonadotropin releasing hormone (GnRH) and a combination of PGF2α + GnRH, respectively. Descriptive statistical analysis was performed. The results revealed that all the three protocols induced and synchronized estrous were almost synchronous in all the treated groups. However, protocol 3 revealed a significantly (p<0.05) better result of 70% pregnancy rate compared to other two protocols that equally provided 50% pregnancy rates. The study resolves that protocol 3 be highly recommended to change the mindset of farmers about the spread of reproductive technology in Sudan. Protocols 1 and 2 provided acceptable pregnancy rates that can be enhanced with the improvement of management.

8 COMBINATION OF OESTRUS DETECTION AND FIXED-TIME ARTIFICIAL INSEMINATION IN BEEF HEIFERS FOLLOWING A SHORTENED OESTRADIOL-BASED PROTOCOL THAT PROVIDES FOR A LENGTHENED PROESTRUS

2015 ◽  
Vol 27 (1) ◽  
pp. 96 ◽  
Author(s):  
J. J. de la Mata ◽  
M. Ré ◽  
G. A. Bó
Keyword(s):  
Pregnancy Rate ◽  
Body Condition Score ◽  
Fixed Time ◽  
Beef Cows ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Group V ◽  
Releasing Hormone ◽  
Treatment Groups ◽  
Condition Score

Studies have shown that gonadotropin-releasing hormone-based protocols that reduce the period of progestin insertion and prolong the period from progestin removal to gonadotropin-releasing hormone and fixed-time AI (FTAI; named 5-day Co-Synch) results in similar or higher pregnancy rates than the conventional 7-day Co-Synch protocol in beef cows and heifers (Bridges et al. 2008 Theriogenology 69, 843–851). Similar findings have been reported following the use of an oestradiol-based protocol that also provides for a longer period of proestrus (named J-Synch; de la Mata and Bó 2012 Taurus 55, 17–23). An experiment was designed to compare the J-Synch protocol for synchronization of ovulation that allows for a prolonged proestrus with a conventional 7-day oestradiol-based protocol for FTAI in heifers. Cycling 18-month old Angus and Hereford heifers (n = 208) with a body condition score of 6 to 7 (scale of 1 to 9) were randomly allocated to 1 of 2 treatment groups. Heifers in the 7-day EB group (n = 105) received a progesterone (P4) device (DIB 0.5 g of P4, Syntex SA, Buenos Aires, Argentina) and 2 mg of oestradiol benzoate (EB, Syntex SA) on Day 0 and 500 μg of cloprostenol (PGF; Ciclase DL, Syntex SA) and 0.5 mg oestradiol cypionate (Cipiosyn, Syntex SA) on the day of DIB removal (Day 7). Heifers were also tail painted at the time of DIB removal and observed for signs of oestrus (i.e. tail paint rubbed off). Those with the tail paint rubbed off by 36 h after DIB removal were inseminated 12 h later, whereas those not showing oestrus by 36 h were FTAI at 54 h. Heifers in the J-Synch group (n = 103) received DIB and 2 mg of EB on Day 0 and PGF on the day of DIB removal (Day 6). Heifers in this group were also tail painted at DIB removal, and those with their tail paint rubbed off by 48 h were inseminated 12 h later; those not showing oestrus by 60 h received 100 μg of gonadorelin acetate (gonadotropin-releasing hormone, Gonasyn gdr, Syntex SA) and were FTAI at 72 h after DIB removal. Pregnancy was diagnosed by ultrasonography at 55 days after FTAI (Honda 101V, 5.0-MHz transducer). Data were analysed by logistic regression. Oestrus detection rate and pregnancy rate to FTAI did not differ (P > 0.1) between groups (38.8%, 40/103 and 60.3%, 38/ 63 for heifers in the J-Synch group v. 28.5%, 30/105 and 45.3%, 34/75 for those in the 7-day EB group). However, pregnancy rates to observed oestrus tended (P < 0.09) to be higher and the overall pregnancy rate was significantly higher (P < 0.01) in heifers in the J-Synch group (80.0%, 32/40 and 67.9%, 70 /103) compared with those in 7-day EB group (50%, 15/30 and 46.6%, 49/105). Furthermore, heifers within the J-Synch group that had their tail paint rubbed off by 48 h after DIB removal and were AI 12 h later (i.e. 60 h) had higher (P < 0.05) pregnancy rate than those in the same group that were FTAI. In conclusion, reducing the time of progestin device insertion and lengthening the proestrus period, as in the J-Synch protocol, results in higher pregnancy rates than with the conventional oestradiol-based protocol. Furthermore, the combination of oestrus detection and FTAI would appear to improve the pregnancy outcome even more.

Luteinizing hormone supplementation increases pregnancy rates in gonadotropin-releasing hormone antagonist donor cycles

2004 ◽  
Vol 82 (2) ◽  
pp. 343-347 ◽  
Author(s):  
Belen Acevedo ◽  
Marta Sanchez ◽  
Jose Luis Gomez ◽  
Jorge Cuadros ◽  
Elisabetta Ricciarelli ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Releasing Hormone

7 PREGNANCY RATES IN BEEF HEIFERS SYNCHRONIZED WITH A SHORTENED OESTRADIOL-BASED TREATMENT THAT PROVIDES FOR A PROLONGED PROESTRUS

2015 ◽  
Vol 27 (1) ◽  
pp. 96 ◽  
Author(s):  
A. Menchaca ◽  
R. Nuñez-Olivera ◽  
F. Cuadro ◽  
G. Bo
Keyword(s):  
Treatment Group ◽  
Day Treatment ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Device Removal ◽  
Beef Heifers ◽  
Releasing Hormone ◽  
Secondary Objective ◽  
To Receive

An oestradiol-based protocol (named J-Synch) has been developed recently with the aim of providing for a longer proestrus, enhancing the development of the dominant follicle before ovulation, and increasing pregnancy rates following fixed-time AI (FTAI) in heifers (de la Matta and Bo 2012 Taurus 55, 17–23). Two experiments were performed in Uruguay with 1953 Angus × Hereford crossbred heifers to compare pregnancy rates obtained with the J-Synch protocol with the conventional 7-day oestradiol-based protocol. A secondary objective was to determine the effects of the time of FTAI and the addition of eCG at the time progestin device removal on pregnancy rates. In Experiment 1, 966 heifers received a DIB device (0.5 g of progesterone, Syntex, Buenos Aires, Argentina) plus 2 mg of oestradiol benzoate IM (Syntex) on Day 0. Heifers in the conventional treatment group (n = 485) received cloprostenol (500 μg, Ciclase DL, Syntex) and oestradiol cypionate (0.5 mg, Cipiosyn, Syntex) IM and had their DIB removed on Day 7 a.m. Heifers in this group were then subdivided to be FTAI on Day 9 a.m. or p.m. (i.e. 48 or 56 h after DIB removal). Heifers in the J-Synch treatment group (n = 481) received cloprostenol IM and DIB removal on Day 6 p.m. and received gonadotropin-releasing hormone (100 μg gonadorelin acetate, Gonasyn Gdr, Syntex) on Day 9 a.m.; heifers were then FTAI on Day 9 a.m. or p.m. (i.e. 60 or 72 h after DIB removal). All heifers in this experiment were also treated with 300 IU of eCG (Novormon, Syntex) at DIB removal. In Experiment 2, 987 heifers were treated with the J-Synch protocol as described in Experiment 1. At device removal (Day 6 p.m.), heifers were divided to receive (n = 488) or not (n = 499) 300 IU of eCG IM at that time and were further subdivided to receive gonadotropin-releasing hormone and FTAI on Day 9 a.m. or p.m. (i.e. 60 or 72 h after DIB removal). Pregnancy rates were determined by ultrasonography 30 days after FTAI. Data were analysed using logistic regression, and results are shown in Table 1. J-Synch-treated heifers tended (P < 0.1) to have higher pregnancy rates following FTAI, whereas time of FTAI only affected pregnancy rates following the conventional 7-day treatment (P < 0.05). However, removal of eCG from the J-Synch protocol in Experiment 2 resulted in reduced pregnancy rates when inseminations were done on Day 9 p.m. (P < 0.05). In summary, the addition of eCG to the J-Synch protocol provided for a wider window of insemination times facilitating FTAI in large groups of beef heifers. Table 1.Effect of length of progestin insertion, time of insemination and eCG treatment on pregnancy rates in beef heifers

PROGESTERONE-INDUCED AUGMENTATION OF PITUITARY GONADOTROPHIN RESPONSES TO LUTEINIZING HORMONE-RELEASING HORMONE IN OESTROGEN-PRE-TREATED AMENORRHOEIC WOMEN

1976 ◽  
Vol 83 (4) ◽  
pp. 684-691 ◽  
Author(s):  
Sven Johan Nillius ◽  
Leif Wide
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Follicular Phase ◽  
Reserve Capacity ◽  
Serum Progesterone ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Before And After ◽  
The Mean ◽  
Late Follicular Phase

ABSTRACT Modulating effects of oestradiol-17β and progesterone on the pituitary responsiveness to luteinizing hormone-releasing hormone (LRH) were investigated in 12 women with functional amenorrhoea. The pituitary reserve capacity for gonadotrophin section was investigated with repeated intravenous LRH tests before and after administration of oestradiol-1β followed by either progesterone or saline. Intramuscular injection of 1 mg of oestradiol-17β benzoate resulted in a suppression of both the basal gonadotrophin levels in serum and the gonadotrophin responses to LRH 24 h later. Progesterone, 25 mg im, was then administered in eleven experiments. Six h later, when the mean serum progesterone level had increased to levels similar to those seen in the early post-ovulatory phase of the menstrual cycle, there was a marked augmentation of the pituitary capacity to release both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in response to LRH. This was not found in eight experiments where saline was given instead of progesterone after oestrogen pretreatment. These findings suggest that the greatly increased pituitary sensitivity to LRH at midcycle may be caused not only by the oestradiol increase in blood during the late follicular phase but also in part by the small pre-ovulatory rise of progesterone during the mid-cyclic LH peak. Furthermore, they add further support to the hypothesis that progesterone as well as oestradiol is involved in the induction of the LH peak at midcycle. Progesterone may be of importance to secure the release of enough LH for ovulation and normal corpus luteum formation to occur.

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