scholarly journals Ovarian response to P4-PGF-FSH Treatment in Suffolk sheep and P4-PGF-PMSG Synchronization in Cross-bred Ewes, for IVD and ET Protocol

2021 ◽  
Author(s):  
STEFAN CIORNEI ◽  
Dan DRUGOCIU ◽  
Liliana Margareta Ciornei ◽  
Petru ROŞCA
Keyword(s):  
Embryo Transfer ◽  
Development Program ◽  
Ovarian Response ◽  
Reproductive Activity ◽  
Corpora Lutea ◽  
Rapid Improvement ◽  
Embryo Production ◽  
Multiple Ovulation ◽  
Suffolk Sheep

Abstract BackgroundThe success of an embryo transfer protocol in sheep depends on many factors, but the choice of drugs for the desired superovulation as well as the conception rate are most essential. Reproductive activity in sheep is characterized by a seasonality influenced by several factors such as photoperiod, latitude, temperature, nutrition and breed. Reproductive seasonality and nutritional condition are the main factors that influence embryo production in sheep. In sheep, some anatomical peculiarities limit the application of traditional reproductive biotechnologies used in cattle. MethodsIn vivo embryo production is often referred to as “multiple ovulation and embryo transfer” and involves ovarian superstimulation of the donor female, insemination or mating, uterine flushing for embryo recovery, and either cryopreservation or transfer of collected embryos to recipients. A total number of 60 sheep and 3 rams were included in this study, divided into 2 groups (receptors/donors). Donor Suffolk sheep were treated for superovulation using the P4‐PGF‐FSH protocol while the cross-bred recipients’ group was synchronized with P4-PGF-PMSG. ResultsOn the first day after superovulation, all ovaries had more than 5 dominant follicles, while corpora lutea were later observed in 83.3% sheep. The recovery rate was 83.3% while 72,9% embryos were transferable. Embryos were transferred directly into recipients. Fertility after 30 days was 68.57%, lambing rate was 91.6%, and CR 62.85%. This study showed that veterinary drugs (P4, FSH, LH, PMSG, PGF) used for superovulation were capable to induce estrus and synchronize ovulation in sheep, are topical and in increasing use worldwide. ConclusionsThe aim of this study was to conclude on the effectiveness of a wider on farm in vivo embryo transfer development program in Suffolk sheep, using several veterinary hormones. The application of a multiple ovulation embryo transfer (MOET) protocol has a positive effect in the production of in vivo derived embryos in Suffolk sheep and can guarantee the success of embryo transfer activity to ewes with lower genetic merit. Our research aimed at representing a model for sheep farms for a rapid improvement of productive traits.

scholarly journals Effects of Extra-Long-Acting Recombinant Bovine FSH (bscrFSH) on Cattle Superovulation

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 153
Author(s):  
Miguel A. Gutiérrez-Reinoso ◽  
Constanza J. Aguilera ◽  
Felipe Navarrete ◽  
Joel Cabezas ◽  
Fidel O. Castro ◽  
...  
Keyword(s):  
Embryo Quality ◽  
Ovarian Response ◽  
Superior Performance ◽  
Limiting Factors ◽  
Corpora Lutea ◽  
Sample Collection ◽  
Embryo Production ◽  
Expression Ratio ◽  
Long Acting

Over the last few years, several commercial FSH products have been developed for cattle superovulation (SOV) purposes in Multiple Ovulation and Embryo Transfer (MOET) programs. The SOV response is highly variable among individuals and remains one of the main limiting factors in obtaining a profitable number of transferable embryos. In this study, follicle stimulating hormone (FSH) from different origins was included in two SOV protocols, (a) FSH from purified pig pituitary extract (NIH-FSH-p; two doses/day, 12 h apart, four consecutive days); and (b) extra-long-acting bovine recombinant FSH (bscrFSH; a single dose/day, four consecutive days), to test the effects of bscrFSH on the ovarian response, hormone profile levels, in vivo embryo production and the pluripotency gene expression of the obtained embryos. A total of 68 healthy primiparous red Angus cows (Bos taurus) were randomly distributed into two experimental groups (n = 34 each). Blood sample collection for progesterone (P4) and cortisol (C) level determination was performed together with ultrasonographic assessment for ovarian size, follicles (FL) and corpora lutea (CL) quantification in each SOV protocol (Day 0, 4, 8, and 15). Moreover, FSH profiles were monitorised throughout both protocols (Day 0, 4, 5, 6, 7, 8, 9, 10, and 15). In vivo embryo quantity and quality (total structures, morulae, blastocysts, viable, degenerated and blocked embryos) were recorded in each SOV protocol. Finally, embryo quality in both protocols was assessed by the analysis of the expression level of crucial genes for early embryo development (OCT4, IFNt, CDX2, BCL2, and BAX). P4 and cortisol concentration peaks in both SOV protocols were obtained on Day 15 and Day 8, respectively, which were statistically different compared to the other time-points (p < 0.05). Ovarian dimensions increased from Day 0 to Day 15 irrespective of the SOV protocol considered (p < 0.05). Significant changes in CL number were observed over time till Day 15 irrespective of the SOV protocol applied (p < 0.05), being non- significantly different between SOV protocols within each time-point (p > 0.05). The number of CL was higher on Day 15 in the bscrFSH group compared to the NIH-FSH-p group (p < 0.05). The number of embryonic structures recovered was higher in the bscrFSH group (p = 0.025), probably as a result of a tendency towards a greater number of follicles developed compared to the NIH-FSH-p group. IFNt and BAX were overexpressed in embryos from the bscrFSH group (p < 0.05), with a fold change of 16 and 1.3, respectively. However, no statistical differences were detected regarding the OCT4, CDX2, BCL2, and BCL2/BAX expression ratio (p > 0.05). In conclusion, including bscrFSH in SOV protocols could be an important alternative by reducing the number of applications and offering an improved ovarian response together with better embryo quality and superior performance in embryo production compared to NIH-FSH-p SOV protocols.

314 RELATIONSHIP BETWEEN SERUM ANTI-MULLERIAN HORMONE (AMH), OVARIAN RESERVE, AND EMBRYO PRODUCTION IN SUPEROVULATED HOLSTEIN COWS

2013 ◽  
Vol 25 (1) ◽  
pp. 304 ◽  
Author(s):  
A. Rozner ◽  
J. Verstegen
Keyword(s):  
Embryo Production ◽  
Blood Samples ◽  
Positive Correlation ◽  
Embryo Recovery ◽  
Multiple Ovulation ◽  
Oocyte Collection ◽  
Significant Difference ◽  
Collection Data ◽  
Over Time

The relations between serum anti-Mullerian hormone (AMH), oocyte numbers, and in vivo embryo production in Holstein heifers were evaluated. The AMH levels of 15 unstimulated cows were followed at weekly intervals during their oestrous cycles and monthly for 4 months. Forty-one superovulated heifers were evaluated at ovum pick-up (OPU) performed 20 h after cystorelin administration, and 125 others were evaluated at embryo recovery. Animals were followed over 3 consecutive cycles induced using a modified Ovsynch protocol with 4 days of FSH (Pluset H, Minitube of America, Verona, WI, USA). Blood samples were collected in serum tubes and spun within 2 h. The samples were stored at –20°C until evaluation using the Minitube of America AMH-bovine specific immunoassay (AMH Fertility Assay™). The statistical analyses (ANOVA and data correlation) were performed using Statview 5 with P < 0.05. Serum AMH ranged from 43 to 960 pg mL–1. The average AMH level of all cows was stable during the oestrous cycle and for each of the 4 monthly measurements. There was a high correlation between all values per animal (r2 = 0.9077; P < 0.01), suggesting that AMH levels are consistent during the cycle and for at least 4 consecutive months. Animals that were repeatedly stimulated showed decreasing AMH levels (509 ± 295, 299 ± 210, 211 ± 119) and a decrease in recovered embryos (7.4 ± 4, 5.6 ± 3.8, 4.2 ± 3.2; P = 0.02). The number of oocytes was not altered by multiple stimulations (10.4 ± 9.8, 11.3 ± 6.2, 8.5 ± 7.6; P = 0.75). As AMH and embryo numbers decreased after multiple stimulations, only the first AMH value and results of the first OPU or flush were used to establish following correlation. Serum AMH showed a positive correlation to the number of oocytes (r2 = 0.245) and embryos collected (r2 = 0.27).When separated into AMH categories, low (<100), normal (100–400), and high (>400 pg mL–1), high-AMH OPU animals yielded significantly higher numbers of oocytes than the animals in the normal or low AMH groups (13.8 ± 9.2 v. 9.2 ± 5.2 and 5.6 ± 3.9; P = 0.001). Flushed animals with high AMH levels had significantly higher numbers of embryos than those with low AMH (10.9 ± 7.9 v. 5.7 ± 5; P = 0.002). Comparison of the first AMH value to the average number of oocytes or embryos collected over the course of 3 collections/animal showed a positive correlation to the average number of oocytes/collection from individual OPU donors (r2 = 0.436) and a positive correlation to the average number of embryos/collection from individual donors (r2 = 0.176). When separated into AMH groups, high-AMH flushed animals had significantly higher numbers of embryos than the normal- or low-AMH animals (9.3 ± 3.1 v. 5.7 ± 3.4 and 4.5 ± 2; P = 0.0001). As OPU animals with low AMH were used only once, average oocyte/collection data was not available for this category. A significant difference was observed between the high- and normal-AMH categories (12 ± 3.6 v. 7 ± 2; P = 0.0001). Circulating AMH is stable over time in unstimulated animals but decreases in repetitively stimulated animals. Anti-Mullerian hormone is highly associated with superovulation response and oocyte and embryo production, and its use should improve animal selection to achieve improve efficiency of multiple-ovulation embryo transfer.

147 Simplification of the follicle-stimulating hormone protocol for superovulation of the first follicular wave in sheep

2021 ◽  
Vol 33 (2) ◽  
pp. 181
Author(s):  
C. Brochado ◽  
B. J. Duran ◽  
J. C. L. Motta ◽  
J. D. Kieffer ◽  
A. Pinczak ◽  
...  
Keyword(s):  
Dose Group ◽  
Body Condition Score ◽  
Ovarian Response ◽  
Chorionic Gonadotrophin ◽  
P Value ◽  
Corpora Lutea ◽  
Embryo Production ◽  
Follicular Wave ◽  
Condition Score ◽  
Dose Number

The objective of the present study was to evaluate the effect of length of the FSH superstimulatory treatment on ovarian response and embryo production in sheep. Poll Dorset ewes (n=63) 3.2±0.2 years old weighing 58.5±1.5kg and with a body condition score of 2.7±0.1 (0=emaciated; 5=obese) were used during the transition from the breeding to the non-breeding season. All ewes received an ovarian superstimulatory treatment during the first follicular wave (Day 0 protocol). On Day −9 all ewes received a 0.3-g progesterone intravaginal device (CIDR, Zoetis) for 6 days. On Day −3, the CIDR was removed and all ewes were administered 125μg of cloprostenol sodium intramuscularly (IM) (PGF, estroPLAN, Parnell) and 200IU of equine chorionic gonadotrophin (eCG)+100IU of human chorionic gonadotrophin (hCG) IM (P.G. 600, Merck). Thirty-six hours after CIDR removal (Day −1.5) ewes were administered 100μg of gonadorelin acetate IM (gonadotrophin-releasing hormone, GnRH; Gonabreed, Parnell). Superstimulatory treatments were initiated on Day 0 (84 h after CIDR removal) with a total of 240mg of NIH-FSH-P1 (12 mL, Folltropin, Vetoquinol), and a new CIDR was used from the first to the last FSH dose (6-dose=3 days; 8-dose=4 days). Ewes were randomised to receive the total dose of FSH distributed in eight decreasing doses (8-dose group, n=33) or six decreasing doses (6-dose group, n=30) twice daily 12h apart. Two doses of PGF were administered with the last two doses of FSH, and GnRH was administered 12h after the last FSH administration. Intrauterine AI with fresh semen was performed by laparoscopy 16h after GnRH administration. Ovarian response was determined by laparoscopy 6 days after AI and ova/embryos were collected surgically in ewes with &gt;2 corpora lutea (CL). Data were analysed using generalized linear mixed models (SAS 9.4; SAS Institute Inc.) and presented as mean±s.e.m. in Table 1. The percentage of responding donors (&gt;2 CL) was 93.3% (28/30) and 78.8% (26/33; P=0.5) for the 6-dose and 8-dose groups, respectively. The number of CL tended (P=0.06) to be lesser in ewes in the 6-dose than the 8-dose group. However, no differences (P&gt;0.10) were found in total ova/embryo, fertilized ova, transferable embryos, or freezable embryos. In conclusion, despite a tendency for a greater ovarian response in ewes treated with 8 doses of FSH, embryo yield did not appear to differ after either 6 or 8 doses of FSH administered during the first follicular wave in sheep. Table 1. Ovulatory response and embryo production in responding ewes (&gt;2 corpora lutea) superstimulated with either 6 or 8 doses of FSH during the first follicular wave Outcome Treatment P-value 6-dose 8-dose Number of ewes 28 26 Corpora lutea (n) 14.2±1.7 20.3±2.8 0.06 Total ova/embryos (n) 9.0±1.3 10.9±1.8 0.38 Fertilized ova (n) 8.1±1.4 10.2±1.9 0.34 Fertilized ova (% per ewe) 89.0±5.0 81.7±7.0 0.40 Degenerate embryos 1.3±0.4 2.0±0.8 0.89 Transferable embryos (Grade 1–3) 6.8±1.2 8.2±1.8 0.52 Transferable embryos (% per ewe) 85.7±4.4 75.4±8.4 0.46 Freezable embryos (Grade 1–2) 6.6±1.1 8.2±1.8 0.43 Freezable embryos (% per ewe) 80.5±5.6 75.4±8.4 0.61

scholarly journals Effect of pFSH dose reduction on in vivo embryo production in Dorper ewes

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4215
Author(s):  
João Bosco Loiola Filho ◽  
Alane Pains Oliveira do Monte ◽  
Thais Thatiane Dos Santos Souza ◽  
Mayara De Souza Miranda ◽  
Lívia Correia Magalhães ◽  
...  
Keyword(s):  
Dose Reduction ◽  
Fertilization Rate ◽  
Corpora Lutea ◽  
Device Removal ◽  
Embryo Production ◽  
Chi Square ◽  
Estrus Detection ◽  
Chi Square Test ◽  
Intravaginal Device

To evaluate the effect of pFSH dose on the in vivo embryo production of Dorper ewes in the semi-arid northeast of Brazil, 40 sheep females were distributed into two groups of 20 animals that received intravaginal CIDR for 14 days, and two days before device removal, they received one of the following treatments: in the FSH200 group, the ewes received 200 mg of pFSH; and in the FSH128 group, the ewes received a total of 128 mg in decreasing doses every 12 h. Beginning 12 h after the conclusion of the treatments, estrus detection was performed every four hours using two Dorper rams of proven fertility. The ewes were mated at estrus onset and 24 hours later. Seven days after intravaginal device removal, the superovulatory response was evaluated, and embryo collection was performed using the laparotomy method. The recovered flushings were subjected to embryo searches under a stereomicroscope and classified according to their qualities. Analyses of variance (ANOVAs) and LSD tests were used to compare the different parameters. The data expressed as percentages were analysed by chi-square test. The ovulation rate was higher in the FSH200 group, which had 16.3 ± 0.3 corpora lutea (CL), than in the FSH128 group, which had 11.3 ± 0.3 CL (P<0.05). However, higher fertilization rate (83.6% vs. 62.4%) and higher transferable (86.0% vs. 71.6%) and freezable (67.9% vs. 40.8%) embryo rates were observed in the FSH 128 group compared with the group that received 200 mg. Furthermore, no significant differences in the remaining parameters were observed between the experimental groups (P>0.05), demonstrating that pFSH dose reduction promoted a greater production of freezable and transferable embryos in Dorper ewes subjected to MOET.

scholarly journals 352 THE USE OF PLASMA ANTI-MÜLLERIAN HORMONE IN SHEEP AS AN ENDOCRINE MARKER OF THE OVARIAN RESPONSE TO FOLLICLE-STIMULATING HORMONE IN MULTIPLE-OVULATION EMBRYO TRANSFER PROGRAMS

2015 ◽  
Vol 27 (1) ◽  
pp. 264
Author(s):  
B. Lahoz ◽  
J. L. Alabart ◽  
M. J. Cocero ◽  
D. Monniaux ◽  
S. Fabre ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Pearson Correlation ◽  
Ovarian Follicle ◽  
Animal Health ◽  
Mammalian Species ◽  
Plasma Concentrations ◽  
Corpora Lutea ◽  
Transfer Programs ◽  
Multiple Ovulation ◽  
Highly Correlated

The performance of MOET (multiple-ovulation embryo transfer) programs in sheep is limited, mainly due to variable ovarian responses to FSH superovulation treatments. In several mammalian species, anti-Müllerian hormone (AMH) has been demonstrated to be a good predictor of the ovarian follicle population able to respond to gonadotropins. Therefore, we aimed to evaluate its usefulness in ovine MOET programs. With this goal, two MOET trials involving 24 adult ewes in total were performed. Each ewe received a fluorogestone acetate sponge (Sincropart 30 mg, CEVA Animal Health SA, Barcelona, Spain) which was replaced by a new one after 6 days (T–4). Four days later (T0), the first FSH injection (Folltropin-V, Minitub Ibérica SL, Tarragona, Spain) of a superovulation treatment consisting in 280 IU of FSH administered in 8 decreasing doses was applied. Blood samples were taken at T–4 and T0 using lithium heparin tubes for AMH measurement. Ewes were inseminated 51 h after sponge removal. Eight days after sponge removal, ovulation rate was recorded and embryo recovery was carried out under general anaesthesia. After morphological evaluation, 2 embryos were transferred to each recipient previously synchronized. The plasma concentrations of AMH were determined using the AMH equine ELISA kit (AnshLab, Webster, TX, USA). The sensibility of the assay was 27.8 pg mL–1, and the intra-assay coefficient of variation was 4.8%. Relationships between the AMH concentration of each animal and the number of corpora lutea (CL), embryo recovered and lambs born per donor ewe were tested using the Pearson correlation coefficient. Normality of the variables was assessed by Kolmogorov–Smirnov test. The plasma AMH concentrations at T–4 were highly correlated with those at T0 (r = 0.95; P < 0.01), so both sampling times could be used indistinctly. The plasma AMH concentration at T0 was highly variable between animals, ranging from 0 to 309.1 pg mL–1 (mean ± s.e.m.: 98.4 ± 18.4 pg mL–1). Similarly, the number of CL ranged from 2 to 29 (12.2 ± 1.5), recovered embryos from 0 to 17 (7.6 ± 1.2), and lambs born per donor and session from 0 to 13 (4.5 ± 0.9). The AMH concentration at the beginning of the FSH treatment (T0) was highly correlated with the total number of CL (r = 0.70; P < 0.01), but significance was not attained for AMH with the other variables. The number of CL was also correlated with the number of recovered embryos (r = 0.69; P < 0.01) and lambs born (r = 0.58; P < 0.01). In conclusion, AMH concentrations measured in blood plasma before the FSH treatment could be used to predict the number of CL per donor ewe, and so to improve the efficiency of MOET programs. Further studies are necessary to assess the individual repeatability of a given ewe from session to session as well as the relationship of AMH with other embryo-related variables.

Efficiency of in vivo Embryo Production in Elite Hanwoo and Embryo Transfer

2013 ◽  
Vol 24 (1) ◽  
pp. 23-28
Author(s):  
Gyu-Tae Yeom ◽  
◽  
Hae-Geum Park ◽  
Sung-Woo Kim ◽  
Yoon-Jung Do ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Embryo Production

scholarly journals Oocyte developmental competence in a bovine model of reproductive aging

Reproduction ◽  
2007 ◽  
Vol 134 (2) ◽  
pp. 233-239 ◽  
Author(s):  
Pritpal S Malhi ◽  
Gregg P Adams ◽  
Reuben J Mapletoft ◽  
Jaswant Singh
Keyword(s):  
Embryo Transfer ◽  
Age Groups ◽  
Blastocyst Stage ◽  
Pregnancy Rates ◽  
Developmental Competence ◽  
Corpora Lutea ◽  
Reproductive Aging ◽  
Embryo Production ◽  
Embryo Survival ◽  
Oocyte Developmental Competence

The study was designed to test the hypothesis that aging in cattle is associated with reduced developmental competence of oocytes. The hypothesis was tested by comparing embryo production and pregnancy rates between 13- to 16-year-old cows (n = 6 in Year 1 and n = 9 in Year 2) and their 3- to 6-year-old young daughters (n = 8 in Year 1 and n = 9 in Year 2) after superovulation and transfer of embryos into an unrelated group of young recipients. Embryos were transferred into 2- to 5-year-old recipient cows (n = 99) as singletons (n = 45) or in pairs (n = 54 pairs). Embryo survival in recipients was determined by ultrasonography and by the number of calves born. Between old versus young cows, the number of ovulations (31 ± 4 vs 38 ± 3; P = 0.2) and the number of corpora lutea (25 ± 3 vs 29 ± 2; P = 0.3) did not differ, but fewer (P = 0.04) embryos were recovered from old cows (6 ± 2) than their daughters (12 ± 2). A higher proportion (P < 0.0001) of unfertilized oocytes/uncleaved zygotes were recovered from old cows (222/312, 71%) than their daughters (119/316, 38%). Among the embryos recovered, the proportion of International Embryo Transfer Society Grades 1–2 embryos was similar (P = 0.9) between old (59/90, 66%) and young cows (130/194, 67%). The survival of embryos after transfer into recipients, and the proportion of calves born were also similar between old and young cows. In conclusion, recovery of fewer embryos and a greater proportion of unfertilized oocytes/uncleaved zygotes suggest reduced developmental competence of oocytes from old cows, but there was no difference between age groups in embryo survival after the morula/blastocyst stage.

scholarly journals Effect of pFSH dose reduction on in vivo embryo production in Dorper ewes

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4215 ◽  
Author(s):  
João Bosco Loiola Filho ◽  
Alane Pains Oliveira do Monte ◽  
Thais Thatiane Dos Santos Souza ◽  
Mayara De Souza Miranda ◽  
Lívia Correia Magalhães ◽  
...  
Keyword(s):  
Dose Reduction ◽  
Fertilization Rate ◽  
Corpora Lutea ◽  
Device Removal ◽  
Embryo Production ◽  
Chi Square ◽  
Estrus Detection ◽  
Chi Square Test ◽  
Intravaginal Device

<p>To evaluate the effect of pFSH dose on the <em>in vivo </em>embryo production of Dorper ewes in the semi-arid northeast of Brazil, 40 sheep females were distributed into two groups of 20 animals that received intravaginal CIDR for 14 days, and two days before device removal, they received one of the following treatments: in the FSH200 group, the ewes received 200 mg of pFSH; and in the FSH128 group, the ewes received a total of 128 mg in decreasing doses every 12 h. Beginning 12 h after the conclusion of the treatments, estrus detection was performed every four hours using two Dorper rams of proven fertility. The ewes were mated at estrus onset and 24 hours later. Seven days after intravaginal device removal, the superovulatory response was evaluated, and embryo collection was performed using the laparotomy method. The recovered flushings were subjected to embryo searches under a stereomicroscope and classified according to their qualities. Analyses of variance (ANOVAs) and LSD tests were used to compare the different parameters. The data expressed as percentages were analysed by chi-square test. The ovulation rate was higher in the FSH200 group, which had 16.3 ± 0.3 corpora lutea (CL), than in the FSH128 group, which had 11.3 ± 0.3 CL (P&lt;0.05). However, higher fertilization rate (83.6% vs. 62.4%) and higher transferable (86.0% vs. 71.6%) and freezable (67.9% vs. 40.8%) embryo rates were observed in the FSH 128 group compared with the group that received 200 mg. Furthermore, no significant differences in the remaining parameters were observed between the experimental groups (P&gt;0.05), demonstrating that pFSH dose reduction promoted a greater production of freezable and transferable embryos in Dorper ewes subjected to MOET.</p>

In vivo embryo production in cows superovulated 1 or 2 days after ovum pick-up

2014 ◽  
Vol 26 (4) ◽  
pp. 527 ◽  
Author(s):  
Ricardo S. Surjus ◽  
Alexandre B. Prata ◽  
Marta Borsato ◽  
Fernanda C. S. Z. Mattos ◽  
Mariana C. Martins da Silveira ◽  
...  
Keyword(s):  
Least Squares ◽  
Corpora Lutea ◽  
Embryo Production

The present study evaluated superovulatory responses and in vivo embryo production in cows treated with FSH starting 1 or 2 days after ovum pick-up (OPU). Thirty-three non-lactating Nelore cows were subjected to aspiration of all follicles ≥3 mm for OPU. After OPU, cows were randomly divided into two groups in which the follicle superstimulatory treatments with FSH started 1 or 2 days after OPU (Groups D1 and D2, respectively). Data are presented as the least squares mean ± s.e.m. The number of follicles ≥3 mm before OPU was similar between groups (~34); however, cows in Group D2 had more follicles ≥3 mm on the first day of FSH (15.2 ± 2.3 vs 7.6 ± 1.7; P = 0.04) and a higher ratio of the number of follicles at first FSH/number of follicles before OPU (0.41 ± 0.04 vs 0.24 ± 0.02; P = 0.01). In addition, Group D2 cows had a greater superovulatory response than did cows in Group D1 (18.9 ± 2.8 vs 9.1 ± 1.9 corpora lutea, respectively; P < 0.03). However, there was no difference in the total number of recovered ova and embryos from cows in Groups D2 and D1 (5.1 ± 1.4 vs 4.9 ± 1.3, respectively; P > 0.10). Nevertheless Group D2 cows had more freezable embryos than Group D1 cows (3.2 ± 1.1 vs 1.3 ± 0.5, respectively; P < 0.05). Cows from Group D2 had a much higher proportion (P < 0.001) of follicles ≥8 mm compared with follicles ≥6 mm and <8 mm at the time of the last treatment with FSH. In conclusion, to obtain a greater production of viable embryos in superovulated cows after OPU, it is recommended to wait at least 2 days before starting FSH treatment.

scholarly journals GnRH or estradiol benzoate combination with CIDR improves in-vivo embryo production in bovines (Bos indicus and Bos taurus) under subtropics

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12077
Author(s):  
Khalid Mahmood ◽  
Muhammad Zahid Tahir ◽  
Mahboob Ahmad Butt ◽  
Shazia Mansoor Qureshi ◽  
Amjad Riaz
Keyword(s):  
Bos Taurus ◽  
Bos Indicus ◽  
Estradiol Benzoate ◽  
Limiting Factors ◽  
Control Group ◽  
Corpora Lutea ◽  
Embryo Production ◽  
Varied Response ◽  
Donor Cows

Multiple Ovulation and Embryo Transfer (MOET) technology is a potential technique to upgrade livestock species’ genetics. The varied response to super-stimulatory treatments remains one of the limiting factors to this technology’s widespread use. The present study was aimed to improve the superovulation response and in-vivo embryo production by using controlled internal drug release (CIDR)-GnRH or CIDR-EB (Estradiol Benzoate) along with conventional superovulation protocol in Holstein Frisian (HF): Bos taurus; n = 42) and Crossbred (XB: Cholistani (Bos indicus) × HF; n = 28) cows. In the CIDR-GnRH/CIDR-EB treatment, CIDR was implanted in the cows after confirming the presence of a corpus luteum (CL) on the 8th day after estrus. 2 ml GnRH (Lecirelin acetate 0.0262 mg/ml) or 2 mg EB was also administered in CIDR-GnRH/CIDR-EB groups, respectively. Both groups were given super-stimulatory treatment from the 11th day after estrus (FSH in tapering doses twice a day for four consecutive days). On day 13, two doses of 2 ml prostaglandin (75 µg/ml of dextrorotatory cloprostenol) were administered (am: pm), and CIDR was removed the following day. Two artificial inseminations (AI) of the cows were performed (12 h apart) on the 15th day. No CIDR and GnRH/E.B were given in the control group, but the remaining superovulation protocol was the same. Later on, seven days after the first AI, non-surgical embryo flushing was done. The transferable embryos produced from three different superovulation protocols were then transferred into the recipient cows (n = 90) for determining their fertility. Statistical analysis revealed that the number of super-estrus follicles (SEF), multiple corpora lutea (MCL), ovulation/fertilization percentage, fertilized structures recovered (FSR), and transferable embryos (TEs) remained significantly higher (p < 0.05), and days taken for return to estrus (RTE) after embryo collection remained significantly lower (p < 0.05) in CIDR-GnRH (n = 18) and CIDR-EB (n = 15) groups as compared to the control (n = 37). The comparison between XB and HF cows revealed that the TEs production in CIDR-GnRH (XB = 5 vs HF = 13) and CIDR-EB (XB = 6 vs HF = 9) based superovulation protocols were 11.60  ±  4.08 vs 04.31  ±  0.98 and 09.33  ±  1.78 vs 05.22  ±  1.36, respectively. TEs production in XB cows (n = 5) of the CIDR-GnRH group was significantly higher (11.60  ±  4.08) than other groups. On the other hand, the days taken for RTE after embryo collection remained significantly lower (p < 0.05) in HF cows of treatment groups. However, the fertility of TEs was neither affected significantly (p > 0.05) by the superovulation protocol used nor by breed differences among donor cows. In conclusion, using CIDR-GnRH or CIDR-EB along with conventional superovulation protocol may enhance the efficiency of MOET programs in cattle. Furthermore, XB donor cows demonstrated a better performance than HF donor cows under subtropical conditions.

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