12 Artificial insemination and embryo transfer results in ewes during a long daylength period

2021 ◽  
Vol 33 (2) ◽  
pp. 113
Author(s):  
T. Mittleider ◽  
S. Collins ◽  
P. Gibbons ◽  
J. Gibbons
Keyword(s):  
Embryo Transfer ◽  
Field Trial ◽  
Prostaglandin F2α ◽  
Late Summer ◽  
Fertilization Rate ◽  
Pregnancy Rates ◽  
Transrectal Ultrasonography ◽  
Chi Squared ◽  
Reproductive Techniques ◽  
Successful Approach

Sheep are polyestrous, short-day breeders (∼11h of daylength), and exhibit oestrus approximately every 16–17 days during the breeding season, usually in late September to late December in the Northern Hemisphere. Progressive sheep producers often use assisted reproductive techniques such as laparoscopic AI and ovarian hyper-stimulation, embryo collection, and embryo transfer (ET) to increase genetic gain, and strive to have early December lambs to target specific show markets, which dictates AI or ET during the late summer. This field trial compared pregnancy rates following AI or ET in July and August (∼14h of daylength) in southwest Virginia (36–38′12″ N). Ewes (AI, n=83; ET recipients, n=33) were synchronized using a modified Ovsynch protocol involving intravaginal progesterone implants for 14 days, prostaglandin F2α (intramuscular) 48h before expected oestrus, and PG600 (IM) and gonadotrophin-releasing hormone (intramuscular) 52 to 54h and 16h before AI, respectively. Ewes were subjected to AI (frozen/thawed semen) regardless of whether they displayed signs of oestrus, and ewes selected as embryo recipients were subjected to a similar protocol but instead received 1 or 2 embryos (based upon the number of viable embryos produced per embryo donor) 6 days following the AI of the embryo donors. Ovarian hyper-stimulation of the embryo donors (n=13) was enabled by twice-daily FSH injections [totalling 350–455IU of Folltropin V (10–13mL)] for the 4 days before AI. Six days following AI, embryos were recovered surgically from the embryo donors (n=13) and yielded an average (±s.e.m.) of 6.6±1.2 total ova, 4.7±1.1 transferable quality embryos, and 1.9±0.8 unfertilized ova per collection. Pregnancy was detected using transrectal ultrasonography at ∼30 days of gestation and the pregnancy rates were analysed using Chi-squared. There was a tendency (P=0.092) for more pregnancies to be established following ET (22/33; 66%) compared with AI (41/83; 49%). There was no statistical relationship between AI ewes or ET recipient ewes that became pregnant relative to whether they displayed signs of oestrus or not. Embryo transfer was a more successful approach to produce pregnancies in ewes compared with AI during long daylength periods in this field trial. Further, ova from hyper-stimulated embryo donor ewes experienced a very high fertilization rate. Future studies will evaluate the ova capability directly via laparoscopic aspiration of ovarian follicles and IVF and evaluation of hyper- and non-hyper-stimulated follicular waves (using transrectal ultrasonography) and endocrine dynamics during different long and short daylength periods. Extending the opportunity to generate embryos and offspring regardless of daylength will assist aggressive sheep producers in reaching their reproductive, financial, and genetic goals.

108 FACTORS AFFECTING PREGNANCY RATES IN RECIPIENTS RECEIVING IN VITRO-PRODUCED EMBRYOS BY FIXED TIME EMBRYO TRANSFER

2016 ◽  
Vol 28 (2) ◽  
pp. 184
Author(s):  
M. Pelizzari ◽  
A. Tribulo ◽  
J. Garzon ◽  
B. Bernal ◽  
R. Tribulo ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Embryo Transfer ◽  
Body Condition Score ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Uterine Horn ◽  
Device Removal ◽  
Embryo Transfer Technique

A retrospective analysis of factors that affect pregnancy rates from 4214 fresh in vitro-produced (IVP) embryos that were transferred at a fixed-time (FTET) in 20 different farms. Recipients were all cycling cows or heifers that were synchronized with 1 of 3 treatments: 1) treatments with progesterone (P4) devices and 2 mg of oestradiol benzoate (EB) on Day 0 (day of insertion) and 24 h after device removal (Day 8); 2) treatments with P4 devices and EB on Day 0, but with 0.5 mg of oestradiol cypionate (ECP) at device removal (Day 8); or 3) treatments with P4 devices and GnRH on Day 0 and a second GnRH 60 h after device removal (Day 5). Cows in all treatment groups also received 500 µg of cloprostenol (prostaglandin F2α) at the time of P4 device removal and 400 IU of eCG either at device removal or 3 days before device removal. All embryos were transferred 7 or 8 days after the expected time of oestrus (24 h after EB, 48 h after ECP or at the time of the second GNRH for each synchronization treatment, respectively). On the day of embryo transfer, recipients were examined by ultrasonography and those with corpus luteum >14 mm in diameter received a fresh, IVP embryo in the uterine horn ipsilateral to the corpus luteum. Pregnancy rates were determined by ultrasonography 35 days after FTET. Data were analysed by logistic regression. Independent variables were classified into the following three categories. 1) Factors related to the recipient and the environment; there were no significant differences in pregnancy rates for corpus luteum diameter (≥14 and <16 mm, ≥16 and <18 mm, or ≥18 mm; P = 0.46), number of corpus luteum (1 or ≥2; P = 0.26), and category of recipient (cow or heifer; P = 0.21). However, there were significant effects of farm (P = 0.01) and body condition score (BCS; P = 0.01). Cows with BCS ≥4.5 (1 to 5 scale) resulted in lower pregnancy rates (4/20, 20.0%) than those with BCS 2 (74/225, 32.9%), 2.5 (502/1434, 35.0%), 3 (570/1467, 38.9%), 3.5 (193/532, 36.3%), and 4 (44/118, 37.3%). 2) Factors related to the synchronization treatment; there were no significant differences between recipients receiving eCG at device removal (84/209, 40.2%) or 3 days before device removal (874/2291, 38.1%; P = 0.35). However, recipients synchronized with P4 devices and ECP had higher (P = 0.01) pregnancy rates (232/483, 48.0%) than those treated with EB (679/1888, 36.0%) or gonadotropin-releasing hormone (47/129, 36.4%). 3) Factors related to the embryo transfer technique; day of the recipient’s oestrous cycle (P = 0.36), stage of embryo transferred (IETS stages 6 or 7; P = 0.62), and operator (P = 0.57) did not affect pregnancy rates. However transfers made in the anterior third of the uterine horn resulted in higher (649/1545, 42.0%) pregnancy rates than those in the mid-third (845/2511, 33.6%) or in the distal third (6/35, 17.1%; P = 0.01). It was concluded that factors related to the recipient and the environment (farm and BCS), the synchronization treatment (ECP), and the embryo transfer technique (site of deposition) affect pregnancy rates in recipients of embryos produced in vitro and transferred at a fixed time.

268 TIMED INSEMINATION OF HEIFERS WITH SEXED SPERM

2008 ◽  
Vol 20 (1) ◽  
pp. 214 ◽  
Author(s):  
J. L. Schenk ◽  
G. E. Seidel
Keyword(s):  
Field Trial ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Labor Costs ◽  
Chi Square ◽  
Chi Square Analysis ◽  
Angus Heifers ◽  
Limited Scope ◽  
Post Onset

The objective of this field trial was to compare pregnancy rates in Angus heifers time-inseminated with sexed sperm 55–56 h or 67–68 h after CIDR removal and administration of 25 mg prostaglandin F2α (PGF2α). Timed insemination eliminates labor costs associated with visual detection of estrus. Anecdotally, use of sexed sperm in commercial timed insemination environments has resulted in reduced pregnancy rates compared to rates for visually observed estrus. However, the optimal fixed time of insemination for sexed sperm has not been studied previously. Sperm were stained at 200 � 106 sperm mL–1 with 49 µm Hoechst 33342 for 45 min at 34.5�C and then diluted to 100 � 106 sperm mL–1 for sorting. Sperm were sexed by flow cytometry/cell sorting at 40 psi using a quasi-cw (pulsed; Vanguard 350-HDM, Spectra-Physics, Mountain View, CA, USA) laser operating at 125 mW, resulting in >91% X-chromosome-bearing sperm. Sorted sperm(2 � 106 total) were packaged into 0.25-mL straws at 10 � 106 sperm mL–1 and cryopreserved. Straws contained >43% progressively motile sperm immediately after thawing for 30 s in a 37�C water bath, as determined by 'track' motility. Angus heifers (n = 67) were synchronized for estrus with IM administration of 100 µg gonadotropin-releasing hormone (GnRH) and a CIDR in place for 7 days, followed by 25 mg PGF2α IM. Heifers were inseminated in the uterine body either 55–56 h (the timing currently recommended for unsexed semen) or 67–68 h after CIDR removal, accompanied by 100 µg GnRH IM, balanced across two inseminators with sperm from two Angus bulls. Estrus was visually detected three times daily but not used as the basis for insemination. Two months post-insemination, pregnancywas determined using ultrasound. Datawere subjected to chi-square analysis. Pregnancy rates for heifers inseminated 55–56 h and 67–68 h after CIDR removal were 34% (n = 11/32) and 46% (n = 16/35), respectively (P > 0.1). Estrus was visually detected for 85% (n = 57/67) of the heifers. Four heifers not detected in estrus became pregnant (40%). Respective pregnancy rates resulting from inseminations 0–12 h and 18–24 h after observed onset of estrus were 25% (7/28) and 55% (16/29), respectively (P < 0.05). Based on the limited scope of this preliminary field trial, insemination of heifers with sexed sperm at 67–68 h post-CIDR removal may be preferable to insemination at 55–56 h. It appears to be best to wait 18 to 24 h post-onset of observed estrus to inseminate heifers with sexed sperm when not using fixed-time insemination procedures. A larger field trial is warranted to more accurately identify the optimal fixed time for insemination using sexed sperm.

144 PREGNANCY RATES FOLLOWING THE TRANSFER OF IN VITRO FERTILIZED EMBRYOS TO RECIPIENTS ON DAY 6, 7, OR 8 AFTER OESTRUS

2015 ◽  
Vol 27 (1) ◽  
pp. 164
Author(s):  
R. C. Fry ◽  
K. L. Fry ◽  
H. A. McCartney ◽  
W. R. Geddes ◽  
K. Geddes
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Pregnancy Rates ◽  
Transfer Program ◽  
In Vitro Production ◽  
Chi Squared ◽  
Grade 3 ◽  
Vitro Production ◽  
Embryo Grade

The aim of this experiment was to investigate the effect of day of synchrony on the pregnancy rate of recipients following the transfer of Day 7 IVF embryos. In addition, the effect of IVF embryo grade and corpus luteum (CL) grade of recipients was determined. A total of 317 cumulus-oocyte complexes collected from 24 dry Brahman cows by TVR were matured, fertilized, and cultured under standard in vitro production procedures (Fry et al. 2003 Theriogenology 59, 446). A total of 89 (44 Grade 1, 43 Grade 2, and 2 Grade 3, IETS classification) in vitro-produced embryos were transferred to parous 4- to 9-year-old dry Brahman cross recipient cattle 7 days after IVF. Two groups of recipient cows were synchronised one day apart with an 8-day CIDR/pg protocol so that oestrous would be concentrated over 3 days with the middle day aligning with the day of IVF (Day 0). Donors that produced a large number of IVF embryos had these divided and transferred into recipients either on Day –1 or Day +1 of synchrony, and those producing less than 4 IVF embryos were transferred into recipients on Day 0. At embryo transfer the ovaries of the recipient were palpated and then scanned by rectal ultrasound and the grade of CL noted (Grade 1 = large distinct CL by palpation, Grade 2 = small distinct CL by palpation, Grade 3 = CL not distinguishable by palpation). Pregnancy was diagnosed by ultrasound scanning on Day 92. Although recipient numbers were low, differences in pregnancy rate between groups were analysed by Chi-squared. Data from the 2 Grade 3 embryos transferred were not included in the analysis (0/2 pregnant). Similar (P > 0.05) pregnancy rates were found when Day 7 IVF embryos were transferred to either Day 6 (17/32 = 53%), Day 7 (9/24 = 38%), or Day 8 (14/31 = 45%) recipients. Furthermore, neither the grade of the embryo (Grade 1: 20/44 = 45%, Grade 2: 20/43 = 47%) nor the grade of recipient CL (Grade 1: 17/45 = 38%, Grade 2: 17/29 = 59%, Grade 3: 6/13 = 46%) effected pregnancy rate (P > 0.05). This experiment demonstrates the flexibility of the IVF embryo to achieve an acceptable pregnancy rate over a range of recipient stages thereby allowing a high usage rate of good-quality recipients in an IVF embryo transfer program.

9 EFFECT OF TIMING OF INSEMINATION WITH SORTED SEMEN ON SUBSEQUENT PREGNANCY RATE IN POSTPARTUM BEEF COWS SYNCHRONIZED WITH A MODIFIED 14-DAY PROGESTERONE PROTOCOL

2014 ◽  
Vol 26 (1) ◽  
pp. 119
Author(s):  
A. J. Davis ◽  
J. G. Powell ◽  
T. D. Lester ◽  
R. W. Rorie
Keyword(s):  
Pregnancy Rate ◽  
Animal Health ◽  
Prostaglandin F2α ◽  
Beef Cows ◽  
Subsequent Pregnancy ◽  
Pregnancy Rates ◽  
Treatment Groups ◽  
Rate Analysis ◽  
Chi Squared ◽  
Pregnancy Status

A study investigated the effect of AI timing on pregnancy rate when using X sorted semen, and whether prostaglandin F2α (PGF2) injection on Day 7 of a modified 14-day progesterone (P4) protocol improved oestrous response in beef cows. Angus-based cows were allotted across treatment groups by cyclicity, parity, weight, body condition, and days postpartum. Treatment 1 (n = 132) cows received a CIDR P4 insert (Eazi-Breed CIDR, Pfizer Animal Health, Groton, CT, USA) on Day 0, with CIDR removal on Day 14, followed by 100 μg of gonadotropin-releasing hormone (GnRH; Factrel, Pfizer) on Day 16, and 25 mg of PGF2 (Lutalyse, Pfizer) on Day 23. Treatment 2 (n = 132) cows received the same synchronization treatment, except for an additional 25 mg dose of PGF2 given on Day 7 of CIDR treatment. Cows were observed for oestrus over an 84-h period and inseminated with X-sorted semen at 9 to 14, 15 to 17, 18 to 21 or 22 to 24 h after detected oestrus, followed 10 days later by exposure to fertile bulls for 45 days. Ultrasonography was used to determine pregnancy status ~45 days after AI and again 45 to 55 days after bull removal. Chi-squared analysis was used to determine the effects of treatment on oestrus response, AI pregnancy, and seasonal pregnancy rates, and the effect of AI timing on pregnancy rate. Analysis of variance was used to determine the effects of treatment on the interval from PGF2 dosing to detected oestrus. Oestrus response to synchronization treatment was similar (P = 0.33) at 76.5 and 71.2% for cows in Treatments 1 and 2, respectively. The mean interval from PGF2 to the onset of oestrus was extended (P = 0.03) ~3 h for cows in Treatment 2 (57.4 v. 54.3 h, respectively). About two-thirds of the cows in each treatment were cyclic at the start of synchronization. The extended interval from PGF2 to observed oestrus was due to an effect on cyclic, but not acyclic, cows in Treatment 2. Of the cows expressing oestrus, 69 and 89% expressed oestrus 48 to 72 h post-PGF2 in Treatments 1 and 2, respectively. Pregnancy rates after AI with sorted semen were similar (P = 0.64) at 63.3 and 66.7% for Treatments 1 and 2, respectively. No differences (P = 0.98) were detected in AI pregnancy rates for insemination intervals ranging from 9 to 24 h after detected oestrus. At the end of the breeding season, seasonal pregnancy rates were also similar (P = 0.74), at 83.3 and 84.9% for cows in Treatments 1 and 2, respectively. The addition of a PGF2 treatment on Day 7 of our 14-day CIDR-based protocol was expected to ensure all cows has sub-luteal P4 concentrations and would develop a persistent follicle capable of ovulation in response to GnRH given on Day 16. Whereas the Day 7 PGF2 treatment had no effect on oestrus response or pregnancy rate, it did result in a more synchronous oestrus within a 24-h period. Results indicate that acceptable pregnancy rates can be achieved in lactating beef cows when using sorted semen over a range of insemination times.

236 SUPEROVULATION IN SHEEP WITH REDUCED INJECTION FSH/eCG PROTOCOLS FOLLOWED BY TRANSFER OF FRESH OR VITRIFIED EMBRYOS

2016 ◽  
Vol 28 (2) ◽  
pp. 250
Author(s):  
R. C. Fry ◽  
R. Mapletroft ◽  
G. A. Bo ◽  
M. M. Izzo ◽  
M. A. Humphris
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Large Scale ◽  
Ovarian Response ◽  
Fertilization Rate ◽  
Chi Squared ◽  
Injection Protocol ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The aim of this experiment was to compare a single FSH/eCG, or double FSH-0.5% hyaluronan/eCG injection protocol with a multiple FSH/eCG injection protocol on the superovulatory response and embryo production in sheep. In addition, the effect of vitrification of these embryos on the pregnancy rate following embryo transfer was evaluated. Eighty Dohne Merino ewes received an 8-day CIDR-S device (0.33 g P4; Zoetis, Florham Park, NJ, USA) plus 10 mg of FSH i.m. (Folltropin-V; Vetoquinol, Lavaltrie, QC, Canada) and 400 IU of eCG i.m. (Pregnecol; Vetoquinol) in 3 treatment groups. Group 1 (n = 21) received a single 10-mg FSH injection in saline and 400 IU of eCG in saline 2.5 days before CIDR withdrawal. Group 2 (n = 23) received 6.7 mg of FSH in hyaluronan (MAP-5, 50 mg; Vetoquinol) and 400 IU of eCG in saline 2.5 days before CIDR withdrawal and 3.3 mg of FSH in hyaluronan 0.5 days before CIDR withdrawal. Group 3 (n = 36) received 7 injections (am, pm) of FSH in saline (2.5, 2.0, 1.5, 1.5, 1.0, 1.0, 0.5 mg) starting 2.5 days before CIDR withdrawal and 400 IU of eCG in saline at the first injection. Ewes were inseminated with semen collected from 1 of 5 rams at 36 to 40 h after CIDR withdrawal. Donor ewes were slaughtered 6 days after AI (Day 0), CL were counted and ova/embryos were collected. Viable embryos were transferred in singles into Day 6 synchronised recipients as either fresh (n = 128) or following vitrification/thawing using the CVM (CryoLogic, Blackburn, VIC, Australia; n = 97; Fry et al. 2005 Reprod. Fertil. Dev. 17, 243). Pregnancy was diagnosed by ultrasound scanning on Day 45. Data for CL and transferable embryo were analysed by the Kruskall-Wallis test and differences between groups determined by the Dunn test. Data for pregnancy rates was compared by chi-squared analysis. The mean number of CL in Groups 2 and 3 were both significantly higher than that in Group 1 (12.3 and 12.0 v. 8.5; P < 0.05). Similarly, the total number of embryos/ova recovered in Groups 2 and 3 were significantly higher than for Group 1 (8.3 and 7.0 v. 5.0; P < 0.05). Group 3 produced more viable embryos than either Group 2 or Group 1 (4.6 v. 2.7 and 2.1; P < 0.05); however, data were skewed by the extensive use of semen from one ram in Group 2 that had a low fertilization rate (28%). The transfer of vitrified/thawed embryos resulted a nonsignificant (P > 0.05) 10% decrease in pregnancy rate compared with fresh embryos (66% v. 76%). In conclusion, the administration of the sustained release FSH-MAP-5 in a 2-injection protocol in sheep was as effective as a multiple FSH injection protocol in inducing an ovarian response but more research is required to elucidate the effect of FSH-MAP-5 on embryo quality. The successful vitrification of sheep embryos provides a promising technique for the storage and transport of embryos in large-scale sheep embryo transfer programs.

104 FACTORS AFFECTING PREGNANCY RATES AND EMBRYO/FETAL LOSSES IN RECIPIENTS RECEIVING IN VITRO-PRODUCED EMBRYOS BY FIXED-TIME EMBRYO TRANSFER

2017 ◽  
Vol 29 (1) ◽  
pp. 160
Author(s):  
A. Tribulo ◽  
A. Cedeño ◽  
B. Bernal ◽  
S. Andrada ◽  
J. L. Barajas ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Body Condition Score ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Gonadotropin Releasing Hormone ◽  
Pregnancy Rates ◽  
Device Removal ◽  
Releasing Hormone ◽  
Condition Score

A retrospective analysis evaluated pregnancy rates and embryo losses with in vitro-produced embryos in a commercial embryo transfer program on 15 different beef farms. Recipients were beef cows and heifers (n = 1841) that were synchronized with 5 different protocols and transferred at a fixed-time (FTET). Recipients were examined by ultrasonography on Day 0, and those with a corpus luteum (CL) or a follicle ≥8 mm in diameter and with body condition score 2 to 4 (1 to 5 scale) were synchronized. The synchronization treatments were as follows. (T1) Recipients received an intravaginal device with 0.5 g of progesterone plus 2 mg of oestradiol benzoate on Day 0; device removal, plus 500 μg of cloprostenol (prostaglandin F2α), 400 IU of eCG, and 0.5 mg of oestradiol cypionate on Day 8; and FTET on Day 17. (T2) This treatment was similar to T1 but 1 mg of oestradiol cypionate was injected at device removal instead of 0.5 mg of oestradiol cypionate. (T3) This treatment was similar to T1 except that animals were tail-painted on Day 8 and observed on Day 10. Those with the tail-paint intact on Day 10 received 100 μg of gonadorelin (gonadotropin-releasing hormone) and all recipients were FTET on Day 17. (T4) Recipients received a progesterone device on Day 0; device removal, prostaglandin F2α, and eCG on Day 5; gonadotropin-releasing hormone on Day 8; and FTET on Day 15. (T5) Recipients received a progesterone device and 2 mg of oestradiol benzoate on Day 0; device removal, prostaglandin F2α, and eCG on Day 6; gonadotropin-releasing hormone on Day 9; and FTET on Day 16. On the day of FTET all recipients with CL ≥18 mm in diameter (G1), ≥16 and <18 mm in diameter (G2), and ≥14 mm and <16 mm in diameter (G3) received in vitro-produced fresh embryos. Pregnancy was diagnosed by ultrasonography at 30 and 60 days of gestation, and data were analysed by logistic regression. The overall proportion of recipients synchronized that were FTET was 80.8% (1487/1841), with a 30-day pregnancy rate to FTET (P/FTET) of 45.6% (678/1487) and the rate of 30- to 60-day embryo/fetal loses on the 528 recipients that were re-checked at 60 days was 12.8% (68/528). There were no significant differences in P/FTET among operators, animal category, time of the year, embryo stage, or body condition score; however, there was a significant effect of farm (P < 0.001) and CL diameter (P < 0.05), but no interaction between CL diameter and farm or treatment (P > 0.1). Recipients with G1 (443/953, 46%) and G2 (221/462, 47%) CL had higher pregnancy rates than those with G3 CL (23/71, 32%). There was a significant effect of synchronization treatment on the proportion of recipients transferred and on P/FTET (P < 0.01) that was highly influenced by farm (farm by treatment interaction P < 0.01). The proportions of recipients selected for embryo transfer were as follows: T1: 386/486, 79.4%; T2: 233/331, 70.3%; T3: 342/377, 90.7%; T4: 126/160, 78.7%; and T5: 400/487, 82.1%. The P/FTET were as follows: T1: 190/386, 49.2%; T2: 96/233, 41.2%; T3: 175/342, 51.1%; T4: 49/126, 38.8%; and T5: 168/400, 42.0%. Although 30- to 60-day embryo/fetal losses were not influenced by synchronization treatments, they were highly influenced by farm (P < 0.001) and ranged from 0 to 34.5%. In conclusion, P/FTET in a commercial program with beef in vitro-produced embryos was influenced by factors related to the recipient (CL diameter) and the environment (farm), whereas embryo/fetal losses were influenced by farm but not treatment or recipient factors.

87 Effect of Treatment with Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) on Pregnancy Rates of Recipient Alpacas Post-Embryo Transfer

2018 ◽  
Vol 30 (1) ◽  
pp. 183
Author(s):  
H. W. Vivanco-Mackie ◽  
M. D. P. Salazar ◽  
M. Miguel-Gonzales ◽  
C. R. Youngs ◽  
M. Asparrin
Keyword(s):  
Body Weight ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Tolfenamic Acid ◽  
Pregnancy Rates ◽  
Control Group ◽  
Chi Squared ◽  
Effect Of Treatment ◽  
The Difference ◽  
Live Fetus

The aim of the study was to improve the pregnancy rate in recipient alpacas using nonsteroidal anti-inflammatpry druds (NSAIDs) at time of embryo transfer. Because most NSAIDs are non-selective inhibitors of cyclooxygenases, which are the rate-limiting enzymes in the formation of prostaglandins, such treatment could temporarily block the production of prositaglandin F2α (PGF2α) and hence maintain corpus luetum (CL) activity long enough to support embryo development and pregnancy. The experiment was carried out in the Peruvian southern highlands (4,100 m elevation). Thirty-one adult alpaca donors were subjected to superovulation and embryo flushing as described previously (Vivanco-Mackie 2013 Proc. 29th Annu. Mtg. AETE, Istanbul, pp. 43-74; http://www.aete.eu/index.php/publications-aete/proceedings/2013/file). From the collected embryos, 20 grade A embryos were selected and transferred fresh into the recipients of the 2 experimental groups. All embryos were collected and transferred at 6.5 days post-mating of the donors with one embryo transferred per recipient. Recipient alpacas (n = 20) were synchronized and induced to ovulate after a selection made by ultrasonography, selecting as recipients the alpacas with follicles >8 mm and then exposing them to vasectomized males followed by IM injection of gonadotropin-releasing hormone (GnRH, 0.0084 mg of acetate of buserelin). Embryo transfers were made by laparoscopically aided laparotomy 6.5 days after ovulation induction as this method has been demonstrated to be more effective in previous trials compared with transcervical non-surgical transfers. At the time of embryo transfer, the recipients were randomly assigned to 1 of the 2 treatments according to the NSAID injected immediately after embryo transfer: Treatment 1 (10 alpacas) was an IM injection of meloxicam at 0.5 mg/kg of body weight; treatment 2 (10 alpacas) was an IM injection of tolfenamic acid at 3 mg/kg of body weight. At the pregnancy test by ultrasound scanning on Day 58 post-transfer, 30% (3/10) of the recipients had a live fetus in treatment 1, whereas treatment 2 had only 10% (1/10).The difference was not significant (P > 0.05) based on Chi-squared analysis. Th historical pregnancy rate obtained with fresh embryos transferred using the same technique and on the same farm where the comparison between NSAIDs was performed was 28.6% at 58 days post-transfer (Vivanco-Mackie et al. 2015 Reprod. Fertil. Dev. 27, 173 abst). Results suggest that there is no difference between tolfenamic acid and meloxicam in their effect on pregnancy rates in alpacas receiving fresh embryo transfers. Compared with historical data of nontreated recipients, results of the present experiment may indicate that the use of NSAIDs at the time of embryo transfer does not improve pregnancy rates in alpaca fresh embryo recipients. However, additional research studies with greater numbers of recipients and an untreated control group are necessary to confirm the preliminary results of the present study. The study was funded by the ‘INNOVATE PERU’ program of the Peruvian Government.

Fertility of heifers and suckled cows inseminated at predetermined intervals after treatment with prostaglandin F2α

1978 ◽  
Vol 91 (2) ◽  
pp. 479-482 ◽  
Author(s):  
H. D. Hafs ◽  
J. G. Manns ◽  
P. D. P. Wood
Keyword(s):  
Side Effects ◽  
Breeding Season ◽  
Field Trial ◽  
Prostaglandin F2α ◽  
Treated Group ◽  
Pregnancy Rates ◽  
Control Groups ◽  
Intramuscular Injections ◽  
Prostaglandin F ◽  
Sources Of Variation

SUMMARYHeifers and suckled cows in 34 herds were included in a field trial using prostaglandin F2α (PGF2α) to control ovulation. Oestrus was induced by two intramuscular injections of PGF2α 10–12 days apart in 592 animals. Of these, 264 were inseminated once at 80 h and 328 were inseminated twice, at 70 and 88 h, after the second injection of PGF2α. Pregnanoy was confirmed by palpation or by calving without further insemination. After adjustment for independent sources of variation in fertility, estimated true pregnancy rates were 59·6 ± 3·0% for cattle inseminated once, and 61·3 ± 2·7% for those inseminated twice at one oestrus, compared with 66·4 ± 3·2% for 220 animals allowed to cycle normally in the same herds (controls).In a sub-sample of 538 animals, semen usage was 15% higher for the treated group inseminated once and 107% higher for the group inseminated twice, than for the controls. The breeding season extended over about 80 days for the control groups, and about 30 days for the treated groups.No side effects attributable to prostaglandin were observed among the treated cattle.

scholarly journals PSII-29 Effects of delayed injection of prostaglandin F2α and TAI in the 14-d CIDR-PG & TAI protocol in replacement beef heifers

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 375-376
Author(s):  
Nicky Oosthuizen ◽  
Gabriela Melo ◽  
Lawton Stewart ◽  
George Seidel ◽  
Graham Cliff Lamb ◽  
...  
Keyword(s):  
Prostaglandin F2α ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Transrectal Ultrasonography ◽  
Dominant Follicle ◽  
Beef Heifers ◽  
Treatment Groups ◽  
Follicle Diameter ◽  
Randomized Design ◽  
Angus Heifers

Abstract To determine the effects of delaying the injection of prostaglandin F2α (PGF) and fixed-time artificial insemination (TAI) in the 14-d CIDR-PG & TAI protocol, 911 Angus heifers at 5 locations were enrolled in a completely randomized design. Within location heifers were randomly assigned to 1 of 2 treatment groups: 1) PG16 (n = 452), heifers received a CIDR insert on d 0 for 14 d, a 25-mg injection of PGF 16 d after CIDR removal [d 30], and a 100-µg injection of gonadotropin-releasing hormone concurrently with TAI 66 ± 2 h later; or 2) PG17 (n = 459), heifers were treated the same as PG16, however, PGF was administered 17 d after CIDR removal [d 31], and heifers were TAI 66 ± 2 h later. Estrus detection patches were applied to heifers at the time of PGF administration and were examined for activation at TAI. Dominant follicle diameter was determined via transrectal ultrasonography at PGF administration and TAI in a subset of heifers (n = 171). Furthermore, transrectal ultrasonography was performed to determine pregnancy rates to TAI (PR/AI) between 30 and 45 d after TAI. Estrus expression prior to TAI was similar (P = 0.50) between treatments (48.9 vs. 52.0%, respectively). Moreover, dominant follicle diameter at PGF and TAI was similar (P ≥ 0.43) between PG16 and PG17 heifers. Pregnancy rates to TAI did not differ (P = 0.48) between treatment groups (46.4 vs. 48.9%, respectively). The results of this experiment indicate that delaying the injection of PGF from d 30 to d 31 along with TAI in the 14-day CIDR-PG & TAI protocol had no effects on fertility parameters in beef heifers. In conclusion, the PGF injection and TAI in the 14-d CIDR-PG & TAI protocol may be delayed, providing more flexibility in scheduling without negatively affecting fertility.

213 THE EFFECT OF eCG TREATMENT IN AN ESTRUS SYNCHRONIZATION PROTOCOL ON PREGNANCY RATES AFTER EMBRYO TRANSFER IN HOLSTEIN HEIFERS

2007 ◽  
Vol 19 (1) ◽  
pp. 223
Author(s):  
T. Okazaki ◽  
E. Sasaki ◽  
K. Hasegawa ◽  
T. Takani ◽  
S. Abe
Keyword(s):  
Embryo Transfer ◽  
Prostaglandin F2α ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Control Group ◽  
Corpora Lutea ◽  
Estrus Synchronization ◽  
Chi Square ◽  
Synchronization Protocol

Recent studies have shown that the presence of accessory or multiple corpora lutea (CL) and increased progesterone (P4) concentrations reduced early embryonic mortality in cattle. The objective of this study was to evaluate the effect of equine chorionic gonadotropin (eCG) treatment on the number of CL, the P4 concentrations, and pregnancy rates after embryo transfer (ET). Holstein heifers (n = 120) from 7 dairy farms received an intravaginal progesterone-releasing device (CIDR; InterAg, Hamilton, New Zealand) and 2 mg IM of estradiol benzoate (EB; Gynandol®; Sankyo, Tokyo, Japan) at random stages of the estrous cycle. After 7 to 9 days, CIDRs were removed and 15 mg of prostaglandin F2α (PG; Pronalgon®; Pfizer Japan, Nagoya, Japan) were administered, followed by 100 µg IM GnRH (Conceral®; Takeda Pharmaceutical Co., Ltd., Osaka, Japan) 2 days later (Day 0). The heifers were placed at random into 3 groups for eCG treatment. The eCG was not administered in a control group (n = 53); heifers in other 2 groups received 1000 IU eCG (Peamex®; Sankyo, Japan) IM at the time (0 h group, n = 37) or 48 h before (48 h group, n = 30) PG injection/CIDR removal. On Day 7, heifers were examined by ultrasonography (Aloka SSD500; Aloka, Tokyo, Japan) for number of CL; heifers with at least one functional CL received an in vivo-derived frozen–thawed embryo by direct transfer. At the same time, a blood sample was collected to determine P4 concentration. Pregnancy rates were determined on Days 30 and 60 by ultrasonography and rectal palpation, respectively. The data were analyzed by ANOVA and means were compared with Fisher's PLSD. Proportional data were analyzed by the chi-square test. P4 concentrations (mean ± SD) on Day 7 were 1.8 ± 1.0, 5.6 ± 3.3, and 2.2 ± 1.1 ng mL−1 for the control, 48 h, and 0 h groups, respectively (48 h vs. control and 0 h; P &lt; 0.001). The number of CL on Day 7 were 1.1 ± 0.4, 2.5 ± 1.4, and 1.8 ± 0.9 for the control, 48 h, and 0 h groups, respectively (control vs. 48 h and 0 h, and 48 h vs. 0 h; P &lt; 0.01). Pregnancy rates did not differ between 0 and 48 h groups but both were higher than in the control group (Table 1). Results suggest that the estrus synchronization protocol with administration of eCG at the time of CIDR removal or 48 h earlier significantly increased the number of CL and the P4 concentration, and improved pregnancy rates in Holstein heifers after ET. Table 1.Pregnancy rates of Holstein heifers synchronized with CIDR and PG and treated with eCG

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