Successful equine in vitro embryo production by ICSI - effect of season, mares' age, breed, and phase of the estrous cycle on embryo production.

This retrospective study aimed at identifying factors that contribute to the success of equine in vitro embryo production by intracytoplasmic sperm injection (ICSI). A total of 7993 ovum pick-up (OPU) sessions were performed, totaling 2540 donor mares and semen from 396 stallions. Oocytes were aspirated at multiple sites in Brazil and were sent to the laboratory, within 6 h from OPU, in pre-maturation medium where they were in vitro matured (IVM) followed by ICSI and in vitro embryo culture for 7-8 days. The number of recovered oocytes, matured oocytes, cleaved embryos and blastocysts were used to explore the effect of age and breed of the donor mare, time of year in which the mare was aspirated and phase of the estrous cycle on the day of follicular aspiration. Mares between 6 and 15 years old were superior to other age groups in most parameters evaluated, including the average number of blastocysts per OPU. The impact of age was similar when evaluated within two breeds, American Quarter Horse (AQHA) and Warmblood mares. We observed that breed (AQHA, Warmblood, Crioulo, Lusitano and Mangalarga) had an important effect on most of the parameter evaluated, including number of oocytes recovered, blastocysts produced per OPU, and blastocyst rates. The overall impact of season was less pronounced than age and breed, with the only statistically significant difference being a higher rate of oocyte maturation during the summer season. Finally, most of the parameters evaluated were superior in follicular phase mares, with or without dominant follicle than luteal phase mares. In conclusion, this retrospective study revealed that breed, age, season and stage of estrous at the time of OPU are all important parameters for the success of equine embryo production by ICSI. This technology enables producing embryos all-year-round from mares of different breeds and ages from OPU-derived oocytes collected at multiple sites.

Transvaginal ultrasound-guided oocyte retrieval in cattle: State-of-the-art and its impact on the in vitro fertilization embryo production outcome.

Transvaginal ultrasound-guided oocyte retrieval (commonly called OPU) and in vitro embryo production (IVP) in cattle has shown significant progress in recent years, in part, as a result of a better understanding of the full potential of these tools by end users. The combination of OPU and IVP (OPU-IVP) has been successfully and widely commercially used worldwide. The main advantages are a greater number of embryos and pregnancies per unit of time, faster genetic progress due to donor quick turn around and more elite sires mating combinations, larger spectrum of female age (calves, prepuberal, heifer, cow) and condition (open, pregnant) from which to retrieve oocytes, a reduced number of sperm (even sexed) required to fertilize the oocytes, among other benefits. OPU-IVP requires significant less donor preparation in comparison to conventional embryo transfer (<50% of usual FSH injections needed) to the extent of no stimulating hormones (FSH) are necessary. Donor synchronization, stimulation, OPU technique, oocyte competence, embryo performance, and its impact on cryopreservation and pregnancy are discussed.

Improvement in early antral follicle development and gene expression modulation prior to follicle aspiration in bovine cumulus-oocyte complexes by equine chorionic gonadotropin.

We aimed to evaluate the morphological ovarian response to equine chorionic gonadotropin (eCG) prior to ovum pick-up (OPU) and its effects on the molecular phenotype of immature cumulus-oocyte complexes (COCs) from Nelore cow (Bos indicus) donors. To this end, 20 Nelore cows were distributed randomly into the synchronized-OPU (Sync-OPU) and synchronized plus stimulated-OPU (Sync + eCG-OPU) groups using a cross-over experimental design, as each cow was used in both treatments. On a random day of the estrus cycle (Day 0), all cows received an intravaginal implant with 1.0 g of progesterone and 2 mg IM of estradiol benzoate. On the morning of Day 3, only the Sync + eCG-OPU group received 400 IU of eCG IM. On the morning of Day 5, the P4 device was removed and OPU was conducted in both groups. Before OPU management, ultrasonography was used to identify and measure the follicles. The aspirated COCs were morphologically classified based on their cumulus cells (CC) layers and the texture of the ooplasm. The COCs classified as Grade 1, Grade 2, and Grade 3 were considered viable and used for the assessment of quality markers. Oocytes and CC were mechanically separated from pools of 25 immature COCs of the Sync-OPU and Sync + eCG-OPU groups immediately after the follicular aspiration and stored at -80 °C until RNA extraction. Relative quantification of several markers for oocyte quality was assessed by RT-qPCR. The eCG treatment increased the number of follicles sized 3.0-5.0 mm and >5.0 mm compared to that in Sync-OPU group. Moreover, the protocol with eCG improved the total number of oocytes and the number of viable oocytes, which is related to a high number of oocytes in Grade 3. Regarding the impact on transcriptional regulation in immature oocytes, the mRNA encoding BMP15, SMAD1, SMAD2, SMAD3, ACACA, and CPT1A was upregulated in Sync + eCG-OPU compared with the Sync-OPU group. Moreover, the relative mRNA abundance of CTSZ, a member of the cathepsins family functionally related to reduced oocyte competence, was lower in the Sync + eCG-OPU group than in the Sync-OPU group. In addition, CC CTSB, CTSS, and CTSK mRNA abundances were lower in the Sync + eCG-OPU group than in the Sync-OPU group. However, the relative abundance of AREG and EREG mRNA was higher in CC recovered from cows stimulated with eCG. In conclusion, the eCG approach addressing follicular stimulation in Nelore cows had a positive impact on early antral follicle development, followed by a positive morphological and molecular phenotype in bovine COCs.

Reproductive seasonality influences oocyte retrieval and embryonic competence but not uterine receptivity in buffaloes.

Since buffaloes are a seasonal, polyestrous species, optimizing reproduction during the non-breeding season is a key factor in increasing the reproductive and productive efficiency of herds. Ovum pick-up associated with in vitro embryo production and embryo cryopreservation is an alternative to reduce seasonal impacts. We studied the effects of seasonality in buffalo oocyte donors and embryo recipients during the favorable and non-favorable breeding seasons. Donors were evaluated for oocyte recovery and blastocyst production rate as dFBS (donors in favorable breeding season) or dNBS (donors in non-favorable breeding season). Embryos produced from dFBS or dNBS were cryopreserved by vitrification or the slow-freeze method for direct transfer and transferred to recipients in the favorable (rFBS) or non-favorable breeding season (rNBS). The heifers or cows were subjected to a fixed-time embryo transfer protocol and conception rates were determined on day 30 and on day 60. The oocyte recovery was lower in dFBS than in dNBS (7.6 vs. 10.0 oocyte/OPU, p = 0.0262); while no difference was found comparing blastocyst production rate (23.7% vs. 30.9% of blastocysts, respectively). Embryos from dFBS resulted in greater (p = 0.0013) conception rates on day 30 compared to dNBS (46.5% vs. 22.4%, respectively), despite the breeding season. The rFBS and rNBS treatments had similar (p = 0.6714) conception rates on day 30 (38.0% vs. 33.0%, respectively), indicating similar uterine receptivity. However, heifers on FBS had higher (p = 0.0003) conception rates on day 30 than cows (73.9% vs. 13.3%, respectively) when receiving embryos from dFBS. Vitrification and direct transfer had similar (p = 0.1698) conception rates on day 30 (30.4% vs. 41.4%, respectively). In conclusion, in vitro-produced embryos derived from dFBS were more competent in establishing pregnancy than dNBS counterparts, independent of recipients' reproductive seasonality. Heifers achieved better conception rates than cows during the favorable breeding season when the embryo came from dFBS. Cryopreserved in vitro produced embryos represent a reliable alternative to reduce seasonal variations in buffalo reproduction. The data elucidate the seasonal effects on embryo competence and on recipients' uterine receptivity, affording new strategies to implement ovum pick-up associated with in vitro embryo production programs in buffalo herds.

Recovery of Equine Oocytes in Ambulatory Practice and Potential Complications.

Field collection of oocytes in mares using transvaginal follicular aspiration (TVA) for embryo production has the potential to revolutionate the equine industry. Protocols for TVA in specialized laboratory settings have been described in the scientific literature since the early 1980s. The objective of this study was to determine the success rate of TVA oocytes recovery under ambulatory conditions. A secondary goal of this study was to determine if TVA is associated with any health complications when performed by recently trained practitioners in the field. Follicles (n = 296) from 66 adult clinically healthy mares were aspirated over a period of 6 days. TVAs were performed by 22 veterinarians with 5-20 years of experience in equine and bovine reproductive medicine, but no previous experience in TVA. Oocytes (n = 145) were recovered. No short- or long-term systemic or local complications were observed following TVA in any of the mares used in this study. Fifty-six out of 66 mares became pregnant within 3 months following TVA. This study shows that with proper training, TVA can be successfully used to obtain equine oocytes with no health complications under field conditions in nonspecialized laboratory settings.

Avaliação dos efeitos da piometra na viabilidade de oócitos caninos imaturos pela utilização do azul cresil brilhante / Evaluation of the effects of pyometra on the viability of immature canine oocytes through the use of brilliant cresyl blue

The bitch is an experimental model of wild and even endangered canids. Therefore, the study of the factors that influence your fertility benefits scientific advances in both segments. Knowing that pyometra is one of the common uterine pathologies in bitches, this work aimed to evaluate the effects of pyometra on the morphology and competence of canine oocytes through the use of Azul Cresil Brilhante (ACB). For this purpose, 1197 canine oocytes that were divided into 2 groups classified as control (healthy) and treatment (pyometra). They were morphologically classified into grade 1 (G1), grade 2 (G2) and grade 3 (G3) and according to the ACB stain as ACB (+) and ACB (­) (not stained). Bitches in the healthy group had higher amounts of total oocytes (795) and better quality (495 oocytes G1) and competence (45 ± 9.8 ACB (+)). The use of ACB was useful to distinguish the competence of the studied oocytes and can be an auxiliary tool for choosing the best oocytes.

Ovum pick-up and in vitro maturation in spotted paca (Cuniculus paca-Linnaeus, 1766).

We tested FSHp, eCG and FSHp + eCG to establish ovum pick-up (OPU) and in vitro maturation method in spotted paca. Eight healthy adult females were subjected to each of four treatments to stimulate ovarian follicular growth. All females were subjected to a hormonal protocol using a single dose of 45 mg of injectable progesterone and single intramuscular injection of 0.075 mg d-cloprostenol on day 6. Ovarian stimulation was carried out as follows: in Group TFE (FSHp and eCG), animals were treated with a single dose of 80 mg of FSHp and 200 IU of eCG intramuscularly on day 6 after the application of progesterone; in Group TF (FSHp), they were treated with a single dose of 80 mg of FSHp intramuscularly on day 6 after application of progesterone; in Group treatment eCG, they were treated with 200 IU of eCG intramuscularly on day 6 after application of progesterone; and in Group TC (saline solution), 1 ml of saline solution was administered to control does. The OPU was performed between 22 and 26 hr after gonadotropin treatments. All recovered oocytes were placed into maturation media and incubated for 24 hr. There were no differences among the mean number of observed follicles, aspirated follicles and oocytes recovered per treatment. Oocyte maturation rates did not differ among groups, except, TF and treatment eCG oocytes had greater maturation rates than TC oocytes. In this study, gonadotropin administration failed to superovulate treated does and increase oocyte retrieval efficiency. Despite the feasibility of the procedure, further studies are needed to develop and refine hormonal protocols for oocyte recovery and in vitro maturation in this species.

Flushing folicular: uma nova alternativa para melhorar a obtenção de oócitos por aspiração ovariana em bovinos / Follicular flushing: a new alternative to improve oocyte recovery by ovarian aspiration in cattle

A lavagem folicular (flushing) associado à aspiração folicular, ou também chamado deflushing folicular (FF) é uma técnica bastante utilizada para a recuperação de oócitos em mulheres. Em animais, já foi empregado para a aspiração folicular transvaginal em equinose na aspiração de ovários bovinos de abatedouros. A recuperação do maior número possível de oócitos é o propósito desse método, pois corresponde a uma ou mais lavagens do folículo puncionado imediatamente após a aspiração folicular. Este trabalho objetivou comparar ouso do FF associado à aspiração folicular (AF) em ovários bovinos de frigoríficos, quanto às taxas de recuperação de oócitos (TRO) e a morfologia dos oócitos. Na AF utilizou-se agulha 18G acoplada a seringa. No FF foi elaborado um sistema manual no laboratório INVITRO/CEBRAN, utilizando equipo, torneira de 3 vias, agulha, seringa, tubo e bomba de vácuo. Neste trabalho, ocorreu apenas uma lavagem intrafolicular. Os oócitos foram classificados de A (COC) a F (Desnudos), conforme o número de camada de células do cumulus, grau de compactação, coloração e uniformidade do citoplasma. Na taxa de obtenção de oócitos por ovário não houve diferença estatística (FF 11±3,12 vs. AF11,63±3,74; p>0,05); porém existiu diferenças na TRO por folículo aspirado (FF88,13%±16,44 vs. AF 71,50%±14,47; p<0,05) e na taxa de recuperação de oócitos grau A(FF 27%±10,98 vs. AF 12,75%±8,56; p<0,05). Além disso, o FF aumentou o tempo de colheita dos oócitos devido a lavagem extra (p<0,01). Com os dados obtidos pode-se observar que o flushing folicular melhorou a TRO em ovários bovinos, favorecendo maior recuperação de COCs.

Follicular lavage (flushing) associated with follicular aspiration, or also called follicular flushing (FF) is a technique widely used for the oocyte recovery in women. In animals, it has already been used by transvaginal follicular aspiration in horses and aspiration of bovine ovaries from slaughterhouses. The recovery of the largest possible number of oocytes is the purpose of this method, as it corresponds to one or more washes of the punctured follicle immediately after follicular aspiration. This study aimed to compare the use of FF associated with follicular aspiration (FA) in bovine ovaries from slaughterhouses, in terms of oocyte recovery rates (ORT) and oocyte morphology. In FA, an 18G needle attached to a syringe was used. In the FF a manual system was elaborated in the INVITRO / CEBRAN laboratory, using parenteral infusion equipment, 3-way stopcock, needle, syringe, tube and vacuum pump. In this study, there was only an intra-follicular lavage. Oocytes were classified from A (COC) to F (Denudes), according to the number of cumulus cell layers, degree of compaction, staining and uniformity of the cytoplasm. There was no statistical difference in the oocytes rate obtained by ovary (FF 11±3.12 vs. FA 11.63±3.74; p> 0.05); however, there were differences in ORT per aspirated follicle (FF 88.13%±16.44 vs. FA 71.50%±14.47;p<0.05) and in the recovery rate of grade A oocytes (FF 27%±10.98 vs. AF 12.75%±8.56;p<0.05). In addition, the FF increased the time to harvest the oocytes due to extra washing(p<0.01). With the data obtained, it can be seen that follicular flushing improved ORT in bovine ovaries, favoring greater recovery of COCs.

Flushing folicular: uma nova alternativa para melhorar a obtenção de oócitos por aspiração ovariana em bovinos / Follicular flushing: a new alternative to improve oocyte recovery by ovarian aspiration in cattle

A lavagem folicular (flushing) associado à aspiração folicular, ou também chamado deflushing folicular (FF) é uma técnica bastante utilizada para a recuperação de oócitos em mulheres. Em animais, já foi empregado para a aspiração folicular transvaginal em equinose na aspiração de ovários bovinos de abatedouros. A recuperação do maior número possível de oócitos é o propósito desse método, pois corresponde a uma ou mais lavagens do folículo puncionado imediatamente após a aspiração folicular. Este trabalho objetivou comparar ouso do FF associado à aspiração folicular (AF) em ovários bovinos de frigoríficos, quanto às taxas de recuperação de oócitos (TRO) e a morfologia dos oócitos. Na AF utilizou-se agulha 18G acoplada a seringa. No FF foi elaborado um sistema manual no laboratório INVITRO/CEBRAN, utilizando equipo, torneira de 3 vias, agulha, seringa, tubo e bomba de vácuo. Neste trabalho, ocorreu apenas uma lavagem intrafolicular. Os oócitos foram classificados de A (COC) a F (Desnudos), conforme o número de camada de células do cumulus, grau de compactação, coloração e uniformidade do citoplasma. Na taxa de obtenção de oócitos por ovário não houve diferença estatística (FF 11±3,12 vs. AF11,63±3,74; p>0,05); porém existiu diferenças na TRO por folículo aspirado (FF88,13%±16,44 vs. AF 71,50%±14,47; p<0,05) e na taxa de recuperação de oócitos grau A(FF 27%±10,98 vs. AF 12,75%±8,56; p<0,05). Além disso, o FF aumentou o tempo de colheita dos oócitos devido a lavagem extra (p<0,01). Com os dados obtidos pode-se observar que o flushing folicular melhorou a TRO em ovários bovinos, favorecendo maior recuperação de COCs.(AU)

Follicular lavage (flushing) associated with follicular aspiration, or also called follicular flushing (FF) is a technique widely used for the oocyte recovery in women. In animals, it has already been used by transvaginal follicular aspiration in horses and aspiration of bovine ovaries from slaughterhouses. The recovery of the largest possible number of oocytes is the purpose of this method, as it corresponds to one or more washes of the punctured follicle immediately after follicular aspiration. This study aimed to compare the use of FF associated with follicular aspiration (FA) in bovine ovaries from slaughterhouses, in terms of oocyte recovery rates (ORT) and oocyte morphology. In FA, an 18G needle attached to a syringe was used. In the FF a manual system was elaborated in the INVITRO / CEBRAN laboratory, using parenteral infusion equipment, 3-way stopcock, needle, syringe, tube and vacuum pump. In this study, there was only an intra-follicular lavage. Oocytes were classified from A (COC) to F (Denudes), according to the number of cumulus cell layers, degree of compaction, staining and uniformity of the cytoplasm. There was no statistical difference in the oocytes rate obtained by ovary (FF 11±3.12 vs. FA 11.63±3.74; p> 0.05); however, there were differences in ORT per aspirated follicle (FF 88.13%±16.44 vs. FA 71.50%±14.47;p<0.05) and in the recovery rate of grade A oocytes (FF 27%±10.98 vs. AF 12.75%±8.56;p<0.05). In addition, the FF increased the time to harvest the oocytes due to extra washing(p<0.01). With the data obtained, it can be seen that follicular flushing improved ORT in bovine ovaries, favoring greater recovery of COCs.(AU)

Time of first polar body extrusion affects the developmental competence of equine oocytes after intracytoplasmic sperm injection.

Assisted reproduction techniques (ARTs) have become widespread in the equine breeding industry. In particular, the combination of oocyte recovery from live mares followed by IVM and intracytoplasmic sperm injection (ICSI) has increased markedly among the ARTs used with valuable or low-fertility animals. There is currently no consensus among research groups regarding the optimal oocyte maturation period to produce high-quality embryos. In this study, we report the maturation dynamics of equine oocytes at different time points, from 20 to 40h (Experiment 1). In addition, in Experiment 2, equine ICSI blastocysts were produced from oocytes that exhibited early (up to 24h) or late (28-30h) extrusion of the first polar body (PB). Blastocyst rates and diameter were recorded and embryo quality was assessed by analysing the number of apoptotic cells and Yes-associated protein 1 (YAP1) expression. By 20h of IVM, 42% of oocytes were mature, and the remaining oocytes matured within the next 17h of IVM. Although no differences were found in cell apoptosis or the number of YAP1-positive cells between groups exhibiting early and late PB extrusion, embryos from the early group (Group I) exhibited an improved total cell number and blastocyst rate compared to embryos from the late group (Group II) (18.60% vs 10.17% respectively).

Efeito da técnica de coleta e do estágio do ciclo estral na recuperação de oócitos de boa qualidade em felinos e caninos domésticos / The effect of recovery technique and stage of estrous cycle on the recoveryof good quality oocytes in domestic felines and canines

A obtenção de oócitos de boa qualidade é essencial para o sucesso de diversas biotécnicas reprodutivas. Objetivou-se determinar o efeito de duas técnicas na recuperação de oócitos de boa qualidade em gatas e cadelas em diferentes estágios reprodutivos. Foram utilizados 43 pares de ovários de gata e 35 de cadela após realização da ovariosalpingohisterectomia eletiva. A fase do ciclo estral foi classificada em inativa, folicular ou luteal. Os ovários da fase folicular foram divididos em três grupos: PUN) punção dos folículos com agulha; PUN+FAT) fatiamento do mesmo ovário já puncionado; e FAT) fatiamento do segundo ovário. Os ovários das fêmeas em fase luteal e inativa foram submetidos ao FAT. Foram obtidos no total 974 oócitos (~23/animal) nas fêmeas felinas e 940 (~27/animal) nas caninas. O fatiamento recuperou número superior (P<0,05) de oócitos. Não houve diferença (P>0,05) entre as técnicas de coleta na qualidade de estruturas recuperadas. A quantidade de oócitos recuperados em cada fase foi similar (P>0,05). Contudo, a fase inativa foi superior à luteal (P<0,05) e semelhante à folicular na quantidade de oócitos de boa qualidade em gatas e não houve diferença em cadelas. Conclui-se que o fatiamento recupera maior quantidade de oócitos, não influenciando em sua qualidade. As fases inativa e folicular recuperam maior quantidade de oócitos de boa qualidade em gatas e não afetam a recuperação em cadelas. Portanto, para otimizar o uso das biotecnologias, deve-se levar em consideração o estágio do ciclo estral em fêmeas felinas e a técnica de coleta utilizada na recuperação de oócitos.(AU)

The recovery of good quality oocytes is essential for the success of various reproductive biotechniques. The aim of this study was to determine the effect of two techniques on the recovery of good quality oocytes in queens and bitches at different reproductive stages. A total of 43 pairs of ovaries of queens and 35 of bitches after elective ovariosalpingohisterectomy were performed. The estrous cycle phase was classified as inactive, follicular or luteal. The ovaries of the follicular phase were allocated into three groups: PUN) puncture of the follicles with a needle; PUN + SLI) slicing of the same ovary already punctured; and SLI) slicing of the second ovary. The ovaries of luteal and inactive females were submitted to SLI. A total of 974 oocytes (~23/animal) were obtained in feline females and 940 (~27/animal) in canines females. The SLI technique recovered superior number (P<0.05) of oocytes. There was no difference (P>0.05) between the collection techniques in the quality of recovered structures. The number of oocytes recovered in each phase was similar (P>0.05). However, the inactive phase was higher than luteal (P<0.05) and similar to the follicular phase in the quantity of good-quality oocytes in queens and there was no difference in bitches. In conclusion, it is preferable to perform the slicing technique to recover more oocytes in both species. Moreover, in queens it is possible to obtain good quality oocytes in the inactive phase and in bitches the estrous cycle phase does not influence the quality.(AU)

Efeito da técnica de coleta e do estágio do ciclo estral na recuperação de oócitos de boa qualidade em felinos e caninos domésticos / The effect of recovery technique and stage of estrous cycle on the recovery of good quality oocytes in domestic felines and canines

A obtenção de oócitos de boa qualidade é essencial para o sucesso de diversas biotécnicas reprodutivas. Objetivou-se determinar o efeito de duas técnicas na recuperação de oócitos de boa qualidade em gatas e cadelas em diferentes estágios reprodutivos. Foram utilizados 43 pares de ovários de gata e 35 de cadela após realização da ovariosalpingohisterectomia eletiva. A fase do ciclo estral foi classificada em inativa, folicular ou luteal. Os ovários da fase folicular foram divididos em três grupos: PUN) punção dos folículos com agulha; PUN+FAT) fatiamento do mesmo ovário já puncionado; e FAT) fatiamento do segundo ovário. Os ovários das fêmeas em fase luteal e inativa foram submetidos ao FAT. Foram obtidos no total 974 oócitos (~23/animal) nas fêmeas felinas e 940 (~27/animal) nas caninas. O fatiamento recuperou número superior (P<0,05) de oócitos. Não houve diferença (P>0,05) entre as técnicas de coleta na qualidade de estruturas recuperadas. A quantidade de oócitos recuperados em cada fase foi similar (P>0,05). Contudo, a fase inativa foi superior à luteal (P<0,05) e semelhante à folicular na quantidade de oócitos de boa qualidade em gatas e não houve diferença em cadelas. Conclui-se que o fatiamento recupera maior quantidade de oócitos, não influenciando em sua qualidade. As fases inativa e folicular recuperam maior quantidade de oócitos de boa qualidade em gatas e não afetam a recuperação em cadelas. Portanto, para otimizar o uso das biotecnologias, deve-se levar em consideração o estágio do ciclo estral em fêmeas felinas e a técnica de coleta utilizada na recuperação de oócitos.

The recovery of good quality oocytes is essential for the success of various reproductive biotechniques. The aim of this study was to determine the effect of two techniques on the recovery of good quality oocytes in queens and bitches at different reproductive stages. A total of 43 pairs of ovaries of queens and 35 of bitches after elective ovariosalpingohisterectomy were performed. The estrous cycle phase was classified as inactive, follicular or luteal. The ovaries of the follicular phase were allocated into three groups: PUN) puncture of the follicles with a needle; PUN + SLI) slicing of the same ovary already punctured; and SLI) slicing of the second ovary. The ovaries of luteal and inactive females were submitted to SLI. A total of 974 oocytes (~23/animal) were obtained in feline females and 940 (~27/animal) in canines females. The SLI technique recovered superior number (P<0.05) of oocytes. There was no difference (P>0.05) between the collection techniques in the quality of recovered structures. The number of oocytes recovered in each phase was similar (P>0.05). However, the inactive phase was higher than luteal (P<0.05) and similar to the follicular phase in the quantity of good-quality oocytes in queens and there was no difference in bitches. In conclusion, it is preferable to perform the slicing technique to recover more oocytes in both species. Moreover, in queens it is possible to obtain good quality oocytes in the inactive phase and in bitches the estrous cycle phase does not influence the quality.

Efeito da técnica de coleta e do estágio do ciclo estral na recuperação de oócitos de boa qualidade em felinos e caninos domésticos / The effect of recovery technique and stage of estrous cycle on the recoveryof good quality oocytes in domestic felines and canines

A obtenção de oócitos de boa qualidade é essencial para o sucesso de diversas biotécnicas reprodutivas. Objetivou-se determinar o efeito de duas técnicas na recuperação de oócitos de boa qualidade em gatas e cadelas em diferentes estágios reprodutivos. Foram utilizados 43 pares de ovários de gata e 35 de cadela após realização da ovariosalpingohisterectomia eletiva. A fase do ciclo estral foi classificada em inativa, folicular ou luteal. Os ovários da fase folicular foram divididos em três grupos: PUN) punção dos folículos com agulha; PUN+FAT) fatiamento do mesmo ovário já puncionado; e FAT) fatiamento do segundo ovário. Os ovários das fêmeas em fase luteal e inativa foram submetidos ao FAT. Foram obtidos no total 974 oócitos (~23/animal) nas fêmeas felinas e 940 (~27/animal) nas caninas. O fatiamento recuperou número superior (P0,05) entre as técnicas de coleta na qualidade de estruturas recuperadas. A quantidade de oócitos recuperados em cada fase foi similar (P>0,05). Contudo, a fase inativa foi superior à luteal (P<0,05) e semelhante à folicular na quantidade de oócitos de boa qualidade em gatas e não houve diferença em cadelas. Conclui-se que o fatiamento recupera maior quantidade de oócitos, não influenciando em sua qualidade. As fases inativa e folicular recuperam maior quantidade de oócitos de boa qualidade em gatas e não afetam a recuperação em cadelas. Portanto, para otimizar o uso das biotecnologias, deve-se levar em consideração o estágio do ciclo estral em fêmeas felinas e a técnica de coleta utilizada na recuperação de oócitos.

The recovery of good quality oocytes is essential for the success of various reproductive biotechniques. The aim of this study was to determine the effect of two techniques on the recovery of good quality oocytes in queens and bitches at different reproductive stages. A total of 43 pairs of ovaries of queens and 35 of bitches after elective ovariosalpingohisterectomy were performed. The estrous cycle phase was classified as inactive, follicular or luteal. The ovaries of the follicular phase were allocated into three groups: PUN) puncture of the follicles with a needle; PUN + SLI) slicing of the same ovary already punctured; and SLI) slicing of the second ovary. The ovaries of luteal and inactive females were submitted to SLI. A total of 974 oocytes (~23/animal) were obtained in feline females and 940 (~27/animal) in canines females. The SLI technique recovered superior number (P0.05) between the collection techniques in the quality of recovered structures. The number of oocytes recovered in each phase was similar (P>0.05). However, the inactive phase was higher than luteal (P<0.05) and similar to the follicular phase in the quantity of good-quality oocytes in queens and there was no difference in bitches. In conclusion, it is preferable to perform the slicing technique to recover more oocytes in both species. Moreover, in queens it is possible to obtain good quality oocytes in the inactive phase and in bitches the estrous cycle phase does not influence the quality.

Impact of short nutrient stimuli with different energy source on follicle dynamics and quality of oocyte from hormonally stimulated goats.

The aim of this study was to verify the effect of the energy source for a short-term diet supplementation on follicular dynamics, ovarian response and oocyte recovery in goats. Thirty Anglo Nubian crossbred does received a diet for 4 weeks to satisfy the nutritional requirements of breeding for adult non-dairy goats. Seven days prior to oocyte recovery (OR), a group of does (n = 10) was supplemented with ground full-fat linseed in the diet (Diet A), whereas a second group of does (n = 10) received crude glycerine in the diet (Diet B). The total mixed ration (TMR) diet was maintained as the Control Diet (n = 10). All animals were oestrous-synchronized by the use of a progesterone insert for 12 days prior to OR. Follicles were stimulated by using pFSH (five 40-mg/ml doses) during the supplementation time. At OR, follicles were counted and recovered oocytes were classified as viable or degenerated. Follicular dynamics was monitored by ultrasonography, and plasma glucose, cholesterol and triglyceride levels were measured during supplementation. Glucose was higher in Diet B and cholesterol in Diet A. Diet B had a lower proportion of small (<3 mm) and large follicles (≥3 mm; p = 0.01). The follicular growth rate was higher in Diet A (p < 0.01), with follicles emerging in the 5th day of supplementation. No differences were observed for follicles counted and oocytes recovered. Thus, the type of energy source supplemented for a short term was capable to alter the follicular dynamics, without affecting the proportion of morphologically viable oocytes upon recovery.

Comparison of two surgical approaches for Laparoscopic Ovum Pick Up in Ewes / Comparação de duas abordagens cirúrgicas para aspiração folicular laparoscópica em ovelhas

The present study had as an aim to evaluate a right lateral access as an alternative method to laparoscopic ovum pick-up (LOPU) in sheep. Twenty-four Santa Ines ewes were randomly assigned in two groups with twelve animals each: RLD - positioned in right lateral decubitus, with 10º head-down tilt; and DD - positioned in dorsal decubitus with 35º head-down tilt. The following parameters were evaluated every 10 minutes during the procedure: total surgical time (ST), visualized follicles (VF), aspirated follicles (AF), recovered oocytes (RO), mean arterial pressure (MAP), heart rate (HR), respiratory rate (fR) and end tidal CO2 pressure (EtCO2). Pre and postoperative arterial hemogasometry parameters (PaO2, PaCO2, pH, CHCO3 and BE) were also evaluated; and serum fibrinogen levels (SFL) on postoperative period. The values of VF, AF, RO, fR, PaO2, pH, CHCO3, BE and SFL were similar between groups, although ST, HR, MAP, EtCO2 and PaCO2 were higher in LG. Regarding operative periods, PaO2 and pH were lower after surgery (PaO2: 79.1±16.4; 79.2±11.7mmHg; pH: 7.30±0.09; 7.32±0.08) in both groups when compared to preoperative (PaO2: 80.1±14.3; 83.4±10.5 mmHg; pH: 7.38±0.05; 7.39±0.05) while PaCO2 (43.6±4.6; 41.9±5.4mmHg) and CHCO3 (22.8±1.5; 22.7±3.0mmol/L) increased (PaCO2: 54.3±10.9; 46.9±6.3mmHg; CHCO3: 24.8±3.4; 24.4±2.7mmol/L) postoperative. This alternative decubitus presented is a viable procedure and did not differ in oocyte recovery rates in ewes. However, entails cardiorespiratory major alterations compared to conventional procedure, making its practical applicability limited.(AU)

O presente estudo teve como objetivo avaliar o acesso lateral direito como um método alternativo para a recuperação de oócitos por laparoscopia (LOPU) em ovelha. Vinte e quatro ovelhas Santa Inês foram distribuídas aleatoriamente em dois grupos com 12 animais: grupo RLD - posicionado em decúbito lateral direito, cefalodeclive com 10º de inclinação; grupo DD - posicionado em decúbito dorsal em cefalodeclive, inclinação de 35º. Foram avaliados, a cada 10 minutos, durante o procedimento cirúrgico: tempo total da cirurgia (ST), folículos visualizados (VF), folículos aspirados (AF), oócitos recuperados (RO), pressão arterial média (MAP), frequência cardíaca (FC), frequência respiratória (fR) e pressão final de CO2 (EtCO2). Também foram avaliados os parâmetros de hemogasometria arterial pré-operatória e pós-operatória (PaO2, PaCO2, pH, CHCO3 e BE), bem como os níveis séricos de fibrinogênio (SFL) no período pós-operatório. Os valores de VF, AF, RO, fR, PaO2, pH, CHCO3, BE e SFL foram semelhantes entre os grupos, embora ST, FC, MAP, EtCO2 e PaCO2 tenham sido maiores em RLD. Os parâmetros PaO2 e pH foram menores após a cirurgia (PaO2: 79,1±16,4; 79,2±11,7mmHg; pH: 7,30±0,09; 7,32±0,08) em ambos os grupos em relação ao momento pré-cirúrgico (PaO2: 80,1±14,3; 83,4±10,5mmHg; pH: 7,38±0,05; 7,39±0,05), enquanto PaCO2 (43,6±4.6; 41,9±5,4mmHg) e CHCO3 (22,8±1,5; 22,7±3.0mmol/L) aumentaram (PaCO2: 54,3±10,9; 46,9±6,3mmHg; CHCO3: 24,8±3,4; 24,4±2,7mmol/L) após a cirurgia. O decúbito lateral é uma alternativa viável para LOPU e não apresenta diferença para a taxa de recuperação oocitária em ovelhas. No entanto, promove alterações cardiorrespiratórias em comparação com o decúbito dorsal, tornando a sua aplicabilidade prática limitada.(AU)

Comparison of two surgical approaches for laparoscopic ovum pick up in wwes / Comparação de duas abordagens cirúrgicas para aspiração folicular laparoscópica em ovelhas

The present study had as an aim to evaluate a right lateral access as an alternative method to laparoscopic ovum pick-up (LOPU) in sheep. Twenty-four Santa Ines ewes were randomly assigned in two groups with twelve animals each: RLD - positioned in right lateral decubitus, with 10º head-down tilt; and DD - positioned in dorsal decubitus with 35º head-down tilt. The following parameters were evaluated every 10 minutes during the procedure: total surgical time (ST), visualized follicles (VF), aspirated follicles (AF), recovered oocytes (RO), mean arterial pressure (MAP), heart rate (HR), respiratory rate (fR) and end tidal CO2 pressure (EtCO2). Pre and postoperative arterial hemogasometry parameters (PaO2, PaCO2, pH, CHCO3 and BE) were also evaluated; and serum fibrinogen levels (SFL) on postoperative period. The values of VF, AF, RO, fR, PaO2, pH, CHCO3, BE and SFL were similar between groups, although ST, HR, MAP, EtCO2 and PaCO2 were higher in LG. Regarding operative periods, PaO2 and pH were lower after surgery (PaO2: 79.1±16.4; 79.2±11.7mmHg; pH: 7.30±0.09; 7.32±0.08) in both groups when compared to preoperative (PaO2: 80.1±14.3; 83.4±10.5 mmHg; pH: 7.38±0.05; 7.39±0.05) while PaCO2 (43.6±4.6; 41.9±5.4mmHg) and CHCO3 (22.8±1.5; 22.7±3.0mmol/L) increased (PaCO2: 54.3±10.9; 46.9±6.3mmHg; CHCO3: 24.8±3.4; 24.4±2.7mmol/L) postoperative. This alternative decubitus presented is a viable procedure and did not differ in oocyte recovery rates in ewes. However, entails cardiorespiratory major alterations compared to conventional procedure, making its practical applicability limited.(AU)

O presente estudo teve como objetivo avaliar o acesso lateral direito como um método alternativo para a recuperação de oócitos por laparoscopia (LOPU) em ovelha. Vinte e quatro ovelhas Santa Inês foram distribuídas aleatoriamente em dois grupos com 12 animais: grupo RLD - posicionado em decúbito lateral direito, cefalodeclive com 10º de inclinação; grupo DD - posicionado em decúbito dorsal em cefalodeclive, inclinação de 35º. Foram avaliados, a cada 10 minutos, durante o procedimento cirúrgico: tempo total da cirurgia (ST), folículos visualizados (VF), folículos aspirados (AF), oócitos recuperados (RO), pressão arterial média (MAP), frequência cardíaca (FC), frequência respiratória (fR) e pressão final de CO2 (EtCO2). Também foram avaliados os parâmetros de hemogasometria arterial pré-operatória e pós-operatória (PaO2, PaCO2, pH, CHCO3 e BE), bem como os níveis séricos de fibrinogênio (SFL) no período pós-operatório. Os valores de VF, AF, RO, fR, PaO2, pH, CHCO3, BE e SFL foram semelhantes entre os grupos, embora ST, FC, MAP, EtCO2 e PaCO2 tenham sido maiores em RLD. Os parâmetros PaO2 e pH foram menores após a cirurgia (PaO2: 79,1±16,4; 79,2±11,7mmHg; pH: 7,30±0,09; 7,32±0,08) em ambos os grupos em relação ao momento pré-cirúrgico (PaO2: 80,1±14,3; 83,4±10,5mmHg; pH: 7,38±0,05; 7,39±0,05), enquanto PaCO2 (43,6±4.6; 41,9±5,4mmHg) e CHCO3 (22,8±1,5; 22,7±3.0mmol/L) aumentaram (PaCO2: 54,3±10,9; 46,9±6,3mmHg; CHCO3: 24,8±3,4; 24,4±2,7mmol/L) após a cirurgia. O decúbito lateral é uma alternativa viável para LOPU e não apresenta diferença para a taxa de recuperação oocitária em ovelhas. No entanto, promove alterações cardiorrespiratórias em comparação com o decúbito dorsal, tornando a sua aplicabilidade prática limitada.(AU)

Three-dimensional levitation culture improves in-vitro growth of secondary follicles in bovine model.

RESEARCH QUESTION: Does a three-dimensional culture system based on magnetic levitation with nanoparticles assembly maintain the follicular structure and viability with adequate growth rates leading to oocyte maturation after long-term culture? DESIGN: Randomized-controlled trial of treatments in a bovine model. Secondary follicles (n = 213) isolated from bovine ovaries were cultured in a two-dimensional system (two-dimensional control) or three-dimensional levitation system with different concentrations (three-dimensional 50 µl/ml, 100 µl/ml and 200 µl/ml) of magnetic nanoparticles. Follicular growth (diameter, daily growth and growth patterns), morphology (normal, degenerated and extruded follicles), antrum formation, oocyte viability and chromatin configuration were assessed. RESULTS: Secondary follicles of three-dimensional 200-µl/ml treatment showed higher viability, antrum formation and lower degeneration rates than two-dimensional control. Also, follicles cultured in the three-dimensional 200-µl/ml treatment presented a most homogenous daily growth rate as shown by the lowest variance and standard deviation. Compared with the two-dimensional control, the proportion of non-growing and slow-growing follicles were 3.8-fold lower and 1.6-fold higher, respectively, in the three-dimensional 200-µl/ml treatment. After in-vitro maturation, the three-dimensional 200-µl/ml had a greater proportion of viable oocytes (1.7-fold) and meiotic resumption rates (2.4-fold) than the two-dimensional control treatment. CONCLUSION: The three-dimensional levitation culture system improves the viability of in-vitro development of bovine secondary follicles, antrum formation and lower extrusion and degeneration rates and adequate growth rate leading to relevant oocyte viability and meiotic resumption after in-vitro maturation. This approach does not require a specific medium, and has the potential as an alternative method to in-vitro follicle culture in several species, including humans.

Likelihood of pregnancy after the transfer of embryos derived from follicle aspiration and in vitro embryo production sessions with different relative efficiencies.

The aim of the present study was to evaluate the likelihood of pregnancy of in vitro-produced (IVP) embryos from batches with distinct relative efficiencies. Data were retrospectively analyzed from 605 transvaginal ultrasonic-guided follicle aspiration sessions (OPU) followed by in vitro embryo production (IVEP) and 2456 fresh embryo transfers (ET), performed between 2008 and 2012 in individuals of the Gir (dairy Bos indicus) breed. The OPU and IVEP were performed using standard procedures by a single group of technicians at the same laboratory facility. Records were stratified into quartiles (I to IV) according to the total of cumulus-oocytes complexes (COC) produced per donor, or in percentile ranges (0%-25%, 26%-50%, 51%-75%, and 76%-100%) for endpoints related to COC quality or efficiency of embryo production. Pregnancy per embryo transfer (P/ET) was compared among quartiles or ranges using the chi-squared test. Donors producing a greater number of total COC (quartile I) also had more viable and grade I COC, and a greater number of embryos than donors ranked in quartiles II, III or IV, respectively (P < 0.0001). Nevertheless, P/ET did not differ (P > 0.05) among embryos produced by donors ranked in Quartiles I to IV. Similarly, there was no difference (P > 0.05) in P/ET for embryos derived from OPU sessions with a relatively greater or lesser percentage of viable or Grade I COC. Cleavage and blastocyst rates within each IVEP batch had no effect (P > 0.05) on P/ET. In conclusion, data suggest that there is no relationship among oocyte yield after OPU, or efficiency of IVEP, and the likelihood of pregnancy after ET of fresh IVP embryos.

Supplementation with sunflower seeds in beef cattle did not impact on oocyte and in vitro embryo production.

Supplementation with compounds rich in linoleic acid, including sunflower seed supplementation, promotes increase in conception rates in cows. We aimed to evaluate whether the sunflower seed (linoleic acid source) supplementation in beef donor females alters the plasma concentrations of cholesterol, triglycerides, HDL and LDL, increases the number and quality of oocytes, increases the cleavage rates and determines an improvement in number and quality of in vitro produced blastocysts. Thus, Nelore females were divided into two groups of 15 animals to receive supplementation with or without sunflower seed for 57 days. Females underwent follicular aspiration and the oocytes were subjected to in vitro embryo production. There was no difference (p > .1) between control group and group supplemented with sunflower seed on the number of displayed follicles; number of aspired oocytes; recovery rate; cleavage rate; number of embryos; number of blastocysts; embryos number of grades I and II; plasma concentrations of total cholesterol, triglycerides; HDL and LDL. Therefore, sunflower seed supplementation in oocyte donors did not increase the number and quality of oocytes, cleavage rates and the number and quality of blastocysts produced in vitro.

Improvement of bovine in vitro embryo production by ovarian follicular wave synchronization prior to ovum pick-up.

This study evaluated the effects of the synchronization of ovarian follicular wave emergence on the efficiency of in vitro embryo production. Bos indicus cows (n = 20) were divided into two groups (control vs. synchronization) and subjected to repeated ovum pick-up (OPU) sessions (8 replicates each, with an interval of 21 days in a 2 × 2 crossover design) and subsequent in vitro embryo production. Cows in the control group (n = 10) were submitted to OPU procedures without any stimulation every 21 days. Animals in the synchronization group received a protocol-based progesterone implant, estradiol benzoate and prostaglandin on a random day of the estrus cycle (Day 0) and the OPU was performed on Day 5. After in vitro production, embryos were transferred to recipients synchronized at a fixed time and the diagnosis was performed 60 days later. An evaluation of the parameters for each OPU session revealed that donors that received the synchronization protocol pre-OPU showed a greater number of embryos (5.9 ± 0.5 vs. 4.5 ± 0.4; P = 0.037), higher rate of embryo production (45.8% vs. 38.5%; P = 0.001) and higher mean number of conceptions per group (2.2 ± 0.2 vs. 1.6 ± 0.2; P = 0.07) in relation to the group that did not receive hormonal treatment. We concluded that synchronization of the follicular wave prior to OPU showed positive effects on in vitro embryo production as well as on pregnancy rates.