19 FACTORS AFFECTING PREGNANCY RATE AFTER ARTIFICIAL INSEMINATION WITH EQUINE SEMEN: PRODUCTION OF THE FIRST FOAL USING FROZEN SEMEN IN KOREA

2011 ◽  
Vol 23 (1) ◽  
pp. 116
Author(s):  
Y. S. Park ◽  
Y. G. Cho ◽  
K. H. Cho ◽  
G. J. Cho

Research in the area of equine artificial insemination (AI) has led to its increased application in field trials (Loomis and Graham, 2008). However, procedures for equine semen collection, cooling and freezing of semen and artificial insemination need further improvement. This study examined the effect of semen preparation and ovulation on equine AI success. Stallion semen was collected via artificial vagina, diluted with skim-milk extender, and preserved by either cooling to 4°C or cryopreservation and storage in liquid nitrogen. Mares were examined by ultrasound for follicle development with every 12 h during oestrus. During AI, semen was inserted into uterine horn adjacent to the ovulating follicle sized over 4 cm and irregular shape. In experiment 1, mares were inseminated with either cooled, cooled-transported, or frozen–thawed semen. Cooled semen was used immediately after collection and cooling. Cooled-transported semen was used 4 h after semen collection and dilution. Semen freezing procedure was followed by Moore et al. (2006). In experiment 2, we examined the effect of buffer (skim-milk extender), which was infused into the uterus at the time of AI with frozen–thawed semen. In experiment 3, we compared AI pregnancy rates for mares ovulating spontaneously v. after treatment with hCG. Pregnancy data were analysed Chi square test where P-values < 0.05 were considered significantly different. In experiment 1, the pregnancy rates after AI using cooled, cooled-transported, and frozen–thawed semen were 60 (10/6), 50 (8/4), and 37.5% (8/3), respectively, and similar among treatments. In experiment 2, the pregnancy rate of mares infused with buffer at AI was 37.5% (8/3) which was higher than that with no buffer (0%; 6/0). In experiment 3, the pregnancy rates of mares were similar between ovulated spontaneously (25%; 8/2) and ovulated with hCG (50%; 8/4). The results suggest that equine semen that has been cooled, cooled and transported or frozen can be successfully used to establish AI pregnancy. Also, the pregnancy rates after AI can be increased by infusing buffer into the uterus at AI or by inducing ovulation with hCG. These experiments resulted in the first foal produced in Korea with frozen–thawed equine semen. This research was supported by Technology Development Program for Agriculture and Forestry, Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea.

1991 ◽  
Vol 71 (1) ◽  
pp. 237-239 ◽  
Author(s):  
P. A. Thacker ◽  
A. D. Gooneratne ◽  
R. N. Kirkwood

Pregnancy rates and litter sizes following insemination of sows with fresh-extended and frozen-thawed semen averaged 71 vs. 53% and 10.6 vs. 4.4, respectively, and was not affected by the addition of 12.5 μg relaxin to semen. These results indicate no relaxin mediated effect on either pregnancy rate or litter size when sows are artificially inseminated with relaxin-supplemented semen. Key words: Artificial insemination, relaxin, sows


2012 ◽  
Vol 24 (1) ◽  
pp. 115
Author(s):  
J. K. Jeong ◽  
H. G. Kang ◽  
I. H. Kim

This study compared pregnancy rates following 2 timed artificial insemination (TAI) protocols using PGF2α + oestradiol or PGF2α + oestradiol + GnRH in dairy cows. Four hundred fifty-five Holstein dairy cows, 2.2 ± 0.1 in parity, 148.3 ± 3.6 days in milk, with corpus luteum of greater than 20 mm diameter confirmed by ultrasonography (Tringa Linear with 5.0 MHz array transducer; Esaote Pie Medical, Maastricht, the Netherlands) were randomly divided into two treatments: an injection of 500 μg of cloprostenol, PGF2α analogue (Iliren cycle BP®, Intervet International GmbH, Unterschleissheim, Germany) and an injection of 2 mg of oestradiol benzoate (EB, SY Esrone, Samyang, Seoul, Korea) 36 h later (PGF2α + EB group, n = 257), or an injection of 500 μg of cloprostenol, an injection of 2 mg of EB 36 h later and an additional injection of 100 μg of gonadorelin, GnRH analogue (Godorel, Uni-Biotech Co., Ltd., Korea) 24 h later (PGF2α + EB + GnRH group, n = 198). All cows in the two groups received TAI 24 h after the EB injection. Pregnancy was determined at 40 to 50 days after TAI by using both ultrasonography and rectal palpation. Pregnancy rates between the PGF2α + EB and PGF2α + EB + GnRH groups were compared by the chi-square test using the SAS program (version 9.1: SAS Institute Inc., Cary, NC, USA). Pregnancy rate following TAI did not differ between the PGF2α + EB (32.7%) and PGF2α + EB + GnRH groups (34.9%; P > 0.05). In conclusion, addition of GnRH for TAI protocol using PGF2α + oestradiol did not improve pregnancy rate in dairy cows.


2012 ◽  
Vol 24 (1) ◽  
pp. 136
Author(s):  
M. B. R. Nogueira ◽  
A. C. F. Farinasso ◽  
A. C. Rezende ◽  
T. L. C. Pinto ◽  
J. C. Souza

Equine AI with frozen semen has become more frequent in reproduction centers, but osmotic shock during thawing is still a major problem as it impairs gamete viability and fertility. To overcome this, multi ultrasonographic (US) exams must be performed to ensure AI at the closest time to ovulation possible. The objective was to evaluate, in vivo, the effects of dilution of the cryoprotectant dimethylphormamide on the success of a fixed timed (20 h post-ovulation) AI protocol, in an attempt to reduce osmotic shock and the intense labour usually required during equine AI with frozen semen. Thirty-five Mangalarga Marchador mares were used in this trial. When dominant follicles reached at least 35 mm in diameter, ovulation was induced with 6 mg of equine gonadotrophin extract (EGE) intravenously. Artificial insemination was performed 20 h after ovulation according to 1 of the following protocols: no dilution (n = 14): three 0.5-mL straws were thawed and the semen deposited by a flexible rod at the uterine tip in the ipsilateral horn where the pre-ovulatory follicle was detected; or dilution (n = 21): three 0.5-mL straws were thawed as described and centrifuged after addition of 1.5 mL of BotuSêmen® extender (1:1 dilution). Pregnancy rates were evaluated between treatments, age and presence of intrauterine liquid (IUL) classes and period between ovulation and AI. Data were analysed as a binomial distribution with the GENMOD procedure (SAS, Cary, NC, USA). Pregnancy rate was higher (P < 0.05) for mares inseminated with diluted semen (42.9%) compared to those inseminated with no semen dilution (4.8%). Age and IUL class did not influence pregnancy rates. It can be concluded that reduction of osmotic stress through the dilution of cryopreserved equine semen increased pregnancy rates after AI. Semen dilution, as tested in this trial, yielded good pregnancy rates in a fixed-time AI protocol in mares, simplified mare management greatly and allowed the use of a fixed-time protocol successfully. Supported by CNPQ, CAPES.


2014 ◽  
Vol 54 (3) ◽  
pp. 356 ◽  
Author(s):  
Francisco Arrebola ◽  
Olga González ◽  
Rafael Torres ◽  
José-Alfonso Abecia

The present study was conducted to determine the effect of different factors on pregnancy rate after artificial insemination (AI) with refrigerated and frozen semen in Payoya goats reared under commercial farm conditions. A total of 820 goats, belonging to 10 farms, was used. The total number of studied inseminations was 1384 over a 4-year period. Factors considered in the study were year, farm, month of AI, age of the goat at AI, dose of progestagen, eCG dose, buck, type of semen (refrigerated or frozen), technician, number of goats to be inseminated (group size), incidences at AI (problems, no problems, trans-cervical insemination), distance from semen collection to farm, number of previous kidding, kidding–AI interval, and milk production. The variable studied was fertility, expressed as successful kidding. Mean fertility was 59%. Six (farm, age, group size, transcervical AI, number of kidding and milk production) of the 15 factors studied presented a significant (P < 0.05) effect on fertility after AI. Our results demonstrated that it is difficult to control all the critical aspects of AI programs at the farm level. These factors should be controlled and the variations that could compromise the chance of being pregnant must be known by technicians. The good fertility results obtained during the non-breeding season emphasise the implementation of this technique so as to improve the competitiveness of the dairy Payoya breed flocks.


2012 ◽  
Vol 24 (1) ◽  
pp. 115
Author(s):  
J. K. Jeong ◽  
H. G. Kang ◽  
I. H. Kim

This study determined the effect of supplementation with oestradiol or oestradiol plus GnRH after PGF2α administration on pregnancy rates after timed artificial insemination (TAI) in dairy cows. Three hundred and six Holstein dairy cows with corpus luteum confirmed by ultrasonography (Tringa Linear with 5.0 MHz array transducer; Esaote Pie Medical, Maastricht, the Netherlands) were randomly allocated to three treatments: a single injection of 500 μg of cloprostenol, PGF2α analogue (Estrumate, Schering-Plough Animal Health, Friesoythe, Germany; PGF2α group, n = 115) designated as 0 h, an injection of 500 μg of cloprostenol and an injection of 1 mg of oestradiol benzoate (EB, SY Esrone; Samyang, Seoul, Korea) 56 h later (PGF2α + EB group, n = 114), or the same treatment as in the PGF2α + EB group and an additional injection of 100 μg of gonadorelin, GnRH analogue (Godorel, Uni-Biotech Co., Ltd., Korea) 24 h later (PGF2α + EB + GnRH group, n = 77). All cows in each group received TAI 80 h after the PGF2α injection. Pregnancy was determined at 40 to 50 days after TAI by using both ultrasonography and rectal palpation. Pregnancy rate among groups were compared by the chi-square test using the SAS program (version 9.1: SAS Institute Inc., Cary, NC, USA). Pregnancy rate following TAI were higher (P < 0.05) in the PGF2α + EB + GnRH group (34/77, 44.2%) than in the PGF2α group (31/115, 27.0%), with the PGF2α + EB group intermediate (39/114, 34.2%). In conclusion, the supplementation with oestradiol plus GnRH after PGF2α administration improved pregnancy rate after TAI in dairy cows. This work was supported by the research grant of the Chungbuk National University in 2011.


2020 ◽  
Vol 32 (2) ◽  
pp. 205
Author(s):  
A. Murtaza ◽  
M. Irfan-ur-Rehman Khan ◽  
M. Abbas ◽  
W. Ahmad ◽  
M. Z. Tahir ◽  
...  

The aim of this study was to determine the optimum time of AI and its relationship with vaginal mucus characteristics relative to the onset of standing oestrus in Beetal goats. For this purpose, goats (n=257) were synchronised for oestrus by administering two doses of prostaglandin F2α (0.075mg intramuscularly, d+ cloprostenol, Dalmazin) 11 days apart during the breeding season (September-December, 2016-2018). The onset of standing oestrus was determined using apronised bucks. Intracervical inseminations were performed at 0 (n=28), 12 (n=84), 24 (n=101), and 36h (n=44) after the onset of standing oestrus using chilled semen (diluted in skim milk at 200×106 spermatozoa per 0.5-mL dose). Color (transparent=1, turbid=2, cheesy/whitish=3), consistency (thin=1, thick=2), and volume (excess=1, scant=2) of the vaginal mucus in goats were observed at the time of inseminations and graded to determine the cumulative mucus score. Resistive index of vaginal mucus (R-value) was monitored at the time of AI using a Draminski heat detector. The intervals to the onset of oestrus among different months of synchronisation, cumulative mucus score, and vaginal electrical resistance at different times of AI were compared using one-way analysis of variance. Pregnancy rates at different times of AI were compared using chi-square analysis, and the Pearson coefficient of correlation was used to correlate mucus color, consistency, and volume with the cumulative mucus score. Following the second prostaglandin F2α administration, the interval to the onset of standing oestrus was longer (P&lt;0.05) in goats synchronised in December than in those synchronised from September to November. The pregnancy rate was lower (P&lt;0.05) in goats inseminated at 0h (28.6%) compared with those inseminated at 12 (58.3%), 24 (56.4%), and 36h (54.5%). However, the pregnancy rates were similar in goats inseminated at 12, 24, and 36h (P&gt;0.05). Odds for pregnancy rate at 12h were 3.5, 1.08, and 1.16 times higher than those at 0, 24, and 36h, respectively. Relative to the time of AI, the cumulative mucus scores varied (P&lt;0.05), and changes in mucus colour and consistency were more highly correlated (r=0.832 and 0.793, respectively; P&lt;0.05) with cumulative mucus score than the mucus volume (r=0.588). Relative to the onset of standing oestrus, the R-value of the mucus was lower at 12h than at 0 and 36h (P&lt;0.05); however, there was no change in R-value of the mucus at 12 and 24h. In conclusion, the optimum time to inseminate Beetal does using chilled semen is 12h following the onset of oestrus, whereas cumulative mucus score and R-value can be used as alternatives if the time of the onset of oestrus is not known.


2010 ◽  
Vol 39 (10) ◽  
pp. 2182-2186
Author(s):  
Cristiane Reinher ◽  
Júlio Otávio Jardim Barcellos ◽  
Vanessa Peripolli ◽  
Ênio Rosa Prates ◽  
Maria Eugênia Andrighetto Canozzi

It was evaluated in this work the effect of calving sub-season on the pregnancy rate of 7,726 multiparous Hereford beef cows grazing on natural pastures in southern Brazil, from 1994 to 2007. Calving sub-season periods were divided in 20-day intervals from August 12th to 31st; from September 1st to 20th; from September 21st to October 10th; from October 11th to 31st; from November 1st to 20th. Calving in each sub-season and pregnancy rate (PR) were analyzed by the Chi-square test. Overall means of each sub-season were 92.7% (from August 12th to 31st), 90.6% (from September 1st to 20th), 82.1% (from September 21st to October 10th), 77.7% (from October 11th to 31st), and 70.6% (from November 1st to 20th). Calving sub-season significantly influenced pregnancy rate. Cows which calved in the initial sub-season showed higher pregnancy rates than cows which calved from the fourth calving sub-season. However this difference did not occur in 1999 and in 2007 since calving rates did not statistically differ among the five sub-seasons. In 1998 and 2004, calving rates were lower and the effects of calving sub-season on pregnancy rates were higher, possibly due to climate variations. In general, pregnancy rate decreases as calving occurs later in the year, particularly in years when the weather adversely affects pasture growth.


2022 ◽  
Author(s):  
Murat Can Demir ◽  
Cihan Kaçar ◽  
Umut Çağın Arı ◽  
Semra Kaya ◽  
Oğuz Merhan ◽  
...  

Abstract The present study aimed to determine the effects of progesterone-based gonadotropin-releasing hormone (GnRH), prostaglandin F2α (PGF2α), and equine chorionic gonadotropin (eCG) injections on progesterone profiles and pregnancy rates in cows with no estrus symptoms within 60 days after parturition. A total of 80 cows were included in the study. All animals had the progesterone-releasing device PRID®Delta placed intravaginally for nine days with an injection of GnRH. On the eighth day, PGF2α was injected, and PRID®Delta was removed from the vagina on day nine. Artificial insemination was carried out 60 hours after PRID®Delta removal. In half of the animals (n = 40), 600 IU of eCG was injected when PRID®Delta was removed on the ninth day before artificial insemination 60 hours later. Blood samples were taken from the tail vein on days 0 and 8 to determine progesterone levels. The pregnancy rate in the group that received eCG was 37.5%, while it was 27.5% in those that did not (P = 0.4). While the dominant follicle diameter was 15.5 mm in cows injected with eCG during timed artificial insemination, the follicle diameter was 12.4 mm in cows with no eCG injection (P <0.001). There were no differences in serum progesterone values in blood samples taken until the time of artificial insemination. However, progesterone values in the blood taken during artificial insemination were 0.94 ng/ml in the eCG- group and 0.72 ng/ml in the eCG+ group (P <0.05). As a result, it was determined that eCG injections, in addition to progesterone-based GnRH and PGF2α applications, increased the pregnancy rates in cows without symptoms of estrus. The dominant follicle diameter was larger in cows treated with eCG during artificial insemination; however, follicle size did not increase the pregnancy rate.


2020 ◽  
Vol 89 (4) ◽  
pp. 307-315
Author(s):  
Hasan Alkan ◽  
Huseyin Erdem

The aim of this study was to investigate the effects of hormonal support on the pregnancy rate in repeat breeder cows. Prostaglandin F2α + Ovsynch oestrus synchronization protocol was applied to the cows. Following the fixed time insemination (day 0), the cows were divided into 4 groups. In Group 1 (n = 42), progesterone releasing intravaginal device (PRID) was placed vaginally at 84 h and removed on the 9th day after the artificial insemination. In Group 2 (n = 40), the cows were administered human chorionic gonadotropin (hCG) on the 7th day. Group 3 (n = 45) was applied a combination of progesterone and hCG. Group 4 (n = 42) was not given any treatment. Blood samples were collected from all cows 4 times on days 3.5, 7, 12, and 18 to evaluate progesterone concentrations. The pregnancy rates were 40.47%, 37.50%, 44.44%, and 30.95% in Group 1, 2, 3, and 4, respectively (P > 0.05). In addition, in cows with progesterone concentrations <2 ng/ml on day 3.5, the pregnancy rates were found to be lower than in the cows with progesterone concentrations >2 ng/ml in Group 4 (P < 0.05). Progesterone supplementation in cows with progesterone concentrations < 2 ng/ml appeared to increase pregnancy rates (P < 0.05) in Groups 1 and 3. As a result, post-insemination hormonal applications in the repeat breeder cows did not increase the pregnancy rate. However, it was concluded that determination of progesterone concentrations on day 3.5 following artificial insemination and then hormonal support in the cows with low concentrations would increased the pregnancy rate.


2018 ◽  
Vol 43 (4) ◽  
pp. 438
Author(s):  
S. Sutiyono ◽  
D. Samsudewa ◽  
A. Suryawijaya

The aim of the study was to examine the synchronization of estrus and artificial insemination in heifers of Ongole grade and Simental-Ongole grade. The research used 19 Ongole Grade (OG) and 18 Simental-Ongole Crossbred (SOC) heifers. This research applied purposive sampling to determine the research population. The criteria to select the population were heifers which have in mature body. The normality of heifer’s reproductive organs were identified by performing rectal palpation, then 50 mg of medroxy progesterone acetate on vaginal sponge was used to synchronized estrus. The estrus heifer was inseminated using frozen semen. The observed parameters were the number of heifers with normal and abnormal reproductive organs, estrus sign and pregnancy. Data were analyzed descriptively. This study showed that OG and SOC with abnormal reproductive organs was 1 heifer (5.56%) and 7 heifers (36.84%), respectively. The responses of estrus synchronization in heifers with normal and abnormal reproductive organs were 94.17% and 100% in OG, and 100% and 42.86% in SOC. Meanwhile, the pregnancy rate was 70.59 and 0% in OG, and 50.00 and 0% in SOC. In conclusion, the number of SOC heifers with abnormal reproductive organs is higher than OG. Estrus synchronization using 50 mg medroxy progesterone acetate increase the amount of estrus and pregnancy in heifers with normal reproductive organs.


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