Use of new recombinant proteins for ovarian stimulation in ruminants

Currently, gonadotropin products (follicle stimulating hormone, FSH, and luteinizing hormone, LH) used in animal reproduction are produced by extraction and purification from abattoir-derived pituitary glands. This method, relying on animal-derived materials, carries the potential risk of hormone contamination and pathogen transmission. Additionally, chorionic gonadotropins are extracted from the blood of pregnant mares (equine chorionic gonadotropin; eCG) or the urine of pregnant women (human chorionic gonadotropin; hCG). However, recent advancements have introduced recombinant gonadotropins for assisted animal reproduction therapies. The traditional use of FSH for superovulation has limitations, including labor requirements and variability in superovulation response, affecting the success of in vivo (SOV) and in vitro (OPU/IVEP) embryo production. FSH treatment for superstimulation before OPU can promote the growth of a homogenous follicular population and the recovery of competent oocytes suitable for IVEP procedures. At present, a single injection of a preparation of long-acting bovine recombinant FSH (rFSH) produced similar superovulation responses resulting in the production of good-quality in vivo and in vitro embryos. Furthermore, the treatment with eCG at FTAI protocol has demonstrated its efficacy in promoting follicular growth, ovulation, and P/AI, mainly in heifers and anestrous cows. Currently, treatment with recombinant glycoproteins with eCG-like activity (r-eCG) have shown promising results in increasing follicular growth, ovulation, and P/AI in cows submitted to P4/E2 -based protocols. Bovine somatotropin (bST) is a naturally occurring hormone found in cows. Recombinant bovine somatotropin (rbST), produced through genetic engineering techniques, has shown potential in enhancing reproductive outcomes in ruminants. Treatment with rbST has been found to improve P/IA, increase donor embryo production, and enhance P/ET in recipients. The use of recombinant hormones allows to produce non-animal-derived products, offering several advantages in assisted reproductive technologies for ruminants. This advancement opens up new possibilities for improving reproductive efficiency and success rates in the field of animal reproduction.(AU)

Analgesia perioperatória de gatas submetidas a ovariohisterectomia eletiva - uso preemptivo de carprofeno ou grapiprant / Perioperative analgesia in cats undergoing elective ovariohysterectomy - preemptive use of carprofen or grapiprant

Background: The nonsteroidal anti-inflammatory drugs (NSAIDs) exert their analgesic effect through peripheral inhibition of prostaglandin synthesis and a variety of other peripheral and central mechanisms. However, NSAIDs are associated with some adverse effects, mainly related to the gastrointestinal, renal, and hepatic systems, highlighting the need for research to develop safer drugs. Therefore, the aim of this study was to evaluate the efficacy of preoperative oral administration of carprofen or grapiprant in female cats submitted to elective ovariohysterectomy on the quality of perioperative analgesia and the need for hypnotic and analgesic drugs. Materials, Methods & Results: Thirty-three adult female cats were selected, without defined breed and healthy based on physical examination, routine laboratory analyses (complete blood count, total protein, Heinz body investigation and serum quantification of alanine transaminase [ALT], aspartate transaminase [AST], gamma glutamyl transpeptidase [GGT], alkaline phosphatase [ALP], urea, frutosamine, and glucose) and negative tests for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). After 3 days of adaptation, they were submitted to ovariohysterectomy by celiotomy and randomly allocated into 2 groups according to the preoperative drug used: GCAR [carprofen - 4 mg/kg, VO, 2 h before surgery; n = 11] and GGRA (grapiprant - 2 mg/kg IV, 2 h before surgery; n = 21]. The cats were pre-medicated with acepromazine 0.05 mg/ kg IV and later submitted to general anesthesia with propofol intravenously. Anesthesia was maintained with isoflurane in 100% oxygen. After anesthetic induction, a continuous infusion of remifentanil at a rate of 10 µg/kg/h was initiated. During the transanesthetic period, the parameters of heart rate; respiratory rate; systolic, mean, and diastolic arterial pressure using the oscillometric method; electrocardiogram; rectal temperature; partial pressure of CO2 at the end of expiration: and partial saturation of O2 in hemoglobin were continuously monitored. The evaluation of nociception was based on the changes in the aforementioned physiological parameters. The rate of remifentanil used did not change over time with the use of carprofen. However, animals that received grapiprant required a lower remifentanil dose at 20, 25, and 30 min during the procedure. The female cats that received carprofen showed an increase in mean heart rate at 30 min compared to that at 20 and 25 min. In the Grapiprant group, the heart rate at 35 min was higher only than that observed at 25 min. Discussion: The remifentanil rate did not differ between the groups, even between the times for GCAR. However, the remifentanil rate was lower from 20 min of the procedure for GGRA. This decrease may be related to a decrease in the need for anesthetics and analgesics by decreasing temperature, which causes decreases in metabolism and surgical stimulation. The increase in systolic, mean, diastolic, and heart rate arterial pressure parameters observed in both treatments after 15 min of anesthesia is related to the nociceptive stimulus resulting from traction and ligation of the ovarian pedicles and maneuvers for exteriorization of the uterus. These are considered the moments of greater surgical stimulus during ovariohysterectomy, evidenced by the greater release of cortisol and increase in physiological parameters. The results of this study show that the administration of carprofen or grapiprant was clinically similar when used preemptively for perioperative analgesia in cats submitted to elective ovariohysterectomy.

Colheita de sêmen e inseminação artificial em onças-pintadas (Panthera onca) / Semen collection and artificial insemination in jaguars (Panthera onca)

A onça-pintada encontra-se classificada como "quase ameaçada" na lista vermelha de animais ameaçados da União Internacional para Conservação da Natureza (IUCN), com tendência ao declínio na América Latina, o que pode afetar o fluxo gênico elevando o risco de endogamia. Técnicas de reprodução assistida (TRAs) como colheita de sêmen e inseminação artificial (IA), são ferramentas que podem se tornar essenciais a manutenção da diversidade genética desses animais. A colheita de sêmen pode ser realizada por eletroejaculação (EEJ) ou colheita farmacológica (CF), sendo que podem ser aplicadas individualmente ou associadas, embora EEJ tenha se mostrado mais eficiente em inseminação artificial (IA) com sêmen a fresco. Para realização de IA a utilização de progestina oral (altrenogest), seguida da aplicação de gonadotropinas exógenas (Gonadotropina Coriônica equina-eCG e Hormônio Luteinizante suíno-pLH), tem se mostrado eficiente, promovendo ovulações consistentes. IA intratubárica (IA-IT) mostrou-se eficiente, tendo a vantagem de utilizar sêmen com baixo número de espermatozoides. O sucesso alcançado com o nascimento do primeiro filhote de Panthera onca utilizando TRAs se deve a vários fatores, dentre eles, a utilização de um novo protocolo hormonal ajustado à espécie; e a utilização da IA-IT, que possibilitou a utilização de sêmen com reduzido número de espermatozoides viáveis por inseminação.(AU)

The jaguar is classified as "near threatened" according International Union for Conservation of Nature red list, with a decreasing trend in the population of Latin America, increasing the risk of inbreeding. Assisted reproduction techniques (ARTs), such as semen collection and artificial insemination (AI), are tools that can become essential to maintain the genetic diversity of jaguars. Semen collection can be performed by electroejaculation (EEJ) or pharmacological collection (PC); and can be applied individually or associated, however EEJ was more efficient for artificial insemination (AI) with fresh semen. To perform Artificial Insemination (AI), oral progestin (altrenogest) followed exogenous gonadotropins (Gonadotropin Chorionic equine-eCG e Hormone Luteinizing porcine-pLH) application was efficient, promoting consistent ovulations. Similarly, laparoscopic oviductal insemination (IA-IT) was efficient, with the advantage to use low viable spermatozoa number by insemination. The success of jaguar cub birth using ARTs is due to several factors, among than, a new hormonal protocol adjusted to the species; and the use of IA-IT, which allowed the reduction in the number of sperm by insemination.(AU)

Efficiency and accuracy of different ovulation inducers after progesterone device removal in crossbred multiparous cows / Eficiência e acurácia de diferentes indutores de ovulação após a remoção do dispositivo de progesterona em vacas mestiças multíparas

The aim of this study was to verify the efficiency and ovulation time after the administration of different inducers for synchronization of ovulation in beef cows. One hundred and eight non-lactating cows were distributed into the control group (CG; untreated; n=28), estradiol benzoate (EB) group (EBG; n=28); 17 beta-estradiol (17ßE) group (17ßEG; n=28), and deslorelin (DES) group (DESG; n=24). On day minus 11 (D-11) of the protocol, the CG underwent application of cloprostenol and ultrasound examination (US); on D0, progesterone (P4) was inserted plus EB; on D7, cloprostenol was applied; on D9, P4 was removed and cloprostenol plus 400 IU of equine chorionic gonadotropin (eCG) was injected. The EBG was subjected to treatment identical to that of the CG, except on D10, when the cows received EB. The 17ßE was subjected to the same protocol used in the CG except for the administration of 17ßE on D10. And, the DESG was subjected to the same treatment as the CG, except on D10, when the group received DES acetate. Twelve hours after the administration of EB, 17ßE and DES, ovarian US were performed every 6 hours. The preovulatory follicle (POF) diameters measured before ovulation were 19.5; 14.7; 18.7 and 19.8 mm respectively for CG, EBG, 17ßEG and DESG; and the time intervals between inducer application and ovulation were 20.2; 18.9; 21.0 and 22.5 hours respectively. In conclusion, all ovulation inducers were efficient in promoting ovulation; the inducers caused ovulation between 18.9 and 22.5 hours; EB promoted ovulation in a shorter time (P<0.05); 17ßE and DES showed greater variation in application/ovulation time between groups.

O objetivo do estudo foi verificar a eficiência e a ovulação após a administração de diferentes indutores para a sincronização da ovulação em vacas de corte. Cento e oito vacas não-lactantes foram distribuídas em grupo controle (GC; não tratadas; n=28); grupo benzoato de estradiol (BE) (GBE; n=28); grupo 17 beta-estradiol (17ßE) (G17ßE; n=28) e grupo deslorelina (DES) (GDES; n=24). No dia menos 11 (D-11) do protocolo, o GC recebeu cloprostenol e exame ultrassonográfico (US); ao D0, dispositivo de progesterona (P4) foi inserido mais BE; ao D7, cloprostenol foi aplicado; ao D9, a P4 foi removida e cloprostenol mais 400 UI de gonadotrofina coriônica equina (eCG) foi injetada. O GBE foi submetido a tratamento idêntico ao do GC, exceto ao D10, quando as vacas receberam BE. o G17ßE foi submetido ao mesmo protocolo usado no CG exceto pela administração de 17ßE ao D10. E, o GDES foi submetido ao mesmo tratamento que o CG, exceto ao D10, quando o grupo recebeu o acetato de DES. Doze horas após a administração de BE, 17ßE e DES, US ovarianos foram realizados a cada 6 horas. O diâmetro do folículo pré-ovulatório (FPO) medido antes da ovulação foi de 19,5; 14,7; 18,7 e 19,8 mm respectivamente para GC, GBE, G17ßE e GDES; e o intervalo de tempo entre a aplicação do indutor e ovulação foi 20,2; 18,9; 21;0 e 22,5 horas respectivamente. Em conclusão, todos os indutores da ovulação foram eficientes em promover a ovulação; os indutores acarretaram ovulação entre 18,9 e 22,5 horas; o BE promoveu a ovulação em menor espaço de tempo (P<0,05); 17ßE e DES demonstraram maior variação em aplicação/tempo de ovulação entre os grupos.

Does combining estradiol cypionate and GnRH for ovulation induction in recipient cows increase pregnancy rate after timed embryo transfer?

Estradiol cypionate (EC) or GnRH have been widely used for ovulation induction in timed embryo transfer (TET). EC administration increases the proportion of cows that show estrus, whereas GnRH promotes more synchronized ovulations. The aim of the present study was to evaluate the potential beneficial effects of combining EC and GnRH in TET. In experiment 1, no difference was observed on serum progesterone concentrations on Day 6 and 13 after GnRH treatment between GnRH and EC+GnRH groups. In experiment 2, pregnancy per embryo transfer (P/ET) did not differ (p = 0.69) between GnRH (62.8%) and EC+GnRH (58.7%) groups. In conclusion, combining EC and GnRH for ovulation induction does not increase progesterone secretion and pregnancy rate after TET in cattle.(AU)

Seminal plasma nerve growth factor signaling on the reproductive physiology of female llamas

The ovulation mechanism is one of the fascinating physiological processes in reproductive biology in mammals. From the reproductive point of view, the species have been classified as spontaneous or induced ovulators. Although the release of GnRH followed by the preovulatory LH surge is shared between both types of ovulation, the stimulus to initiate GnRH release varies between both categories. In spontaneous ovulators, ovulation depends on the systemic concentration of ovarian steroids, however, in induced ovulators, different stimuli such as copulation, environmental, and social cues can facilitate or induce ovulation regardless of the increases in systemic estradiol concentration. In this review, we document evidence that a male-derived protein is the main factor responsible for inducing ovulation and also modulating the ovarian function in the domestic South American camelid, the llama. The neurotrophin beta-Nerve Growth Factor (β-NGF) is the principal factor present in the semen of llamas responsible for inducing ovulation in this species. After the intrauterine deposit of semen during mating, β-NGF is absorbed through the endometrium to reach the circulatory system, where it reaches the hypothalamus and stimulates GnRH release. The potential site of action of this neurotrophin at the brain has not been elucidated, however, hypotheses are raised that the factor may cross the blood-brain barrier and stimulate upstream neuronal networks that lead to the stimulation of GnRH-secreting neurons. It is possible that β-NGF could be sensed at the median eminence without crossing the blood-brain barrier. Finally, it has been observed that this factor is not only a powerful stimulator of ovulation but also has a luteotrophic effect, resulting in the development of a corpus luteum capable of secreting more progesterone when compared to other ovulation-stimulating analogues.(AU)

Use of estradiol cypionate to induce ovulation in buffalo raised in floodplain areas of Itacoatiara, Amazonas / [Uso do cipionato de estradiol na indução da ovulação de búfalas criadas em várzea da região de Itacoatiara, Amazonas]

This study aimed to determine the efficiency of estradiol cypionate (EC) as an ovulation inducer in a Timed Artificial Insemination protocol. 69 buffalo cows received an intravaginal progesterone device and 2mg of estradiol benzoate (EB) at D0. On D9, the intravaginal device was removed and 0.53mg of prostaglandin (PGF2α) and 400UI of equine chorionic gonadotrophin (eCG) were applied. The cows were distributed into two groups: the first group received 1mg of EC (ECG) in D9, and the second group received 1mg of EB (EBG) in D10. Inseminations occurred on D11. Ovarian activity and pregnancy diagnosis were analyzed by ultrasonography. There was no difference (P>0.05) in follicular diameter (9.6 ± 0.89mm vs. 10.7 ± 1.12mm; P=0.06), in ovulation rate (90.9% vs. 90.9%; P=1) and pregnancy rate (58.8% vs. 62.9%; P=0.79), however, buffalo cows from the ECG treatment have less time between P4 removal and ovulation when compared to EBG buffalos (37.4h vs. 52.8h; P=0.001), respectively. Thus, it was concluded that the implantation of TAI in the floodplain of Amazonas is feasible and the use of EC results in successful rates, similar to EB.(AU)

O objetivo deste trabalho foi determinar a eficiência do cipionato de estradiol (CE) como indutor de ovulação em um protocolo de inseminação artificial de tempo fixo. Para isso, 69 búfalas receberam no D0 um dispositivo intravaginal de progesterona e 2mg de benzoato de estradiol (BE). No D9, o dispositivo intravaginal foi removido e foram aplicados 0,53mg de prostaglandina (PGF2α) e 400UI de gonadotrofina coriônica equina (eCG), para, então, os animais serem divididos em dois grupos: um deles (GCE) recebeu 1mg de CE no D9, e o outro (GBE) recebeu 1mg de BE 24h após. As inseminações ocorreram no D11. A atividade ovariana e o diagnóstico de prenhez foram avaliados por ultrassonografia. Não houve diferença (P>0,05) no diâmetro folicular (9,6 ± 0,89mm vs. 10,7 ± 1,12mm; P=0,06), na taxa de ovulação (90,9% vs. 90,9%; P=1) e na taxa de prenhez (58,8% vs. 62,9%; P=0,79), no entanto búfalas do tratamento GCE apresentaram menor tempo entre a remoção da P4 e a ovulação, quando comparadas com as búfalas do GBE (37,4h vs. 52,8h; P=0,001), respectivamente. A implantação da IATF nas várzeas do Amazonas é viável e a utilização do CE resulta em taxas de sucesso similares ao BE.(AU)

A interface entre a saúde humana e a reprodução assistida em primatas não humanos / The interface between human health and assisted reproductive technologies in non-human primates

Os primatas não-humanos (PNHs) são tidos como importantes modelos para estudos biomédicos devido à sua grande similaridade biológica com os seres humanos. As técnicas de reprodução assistida (TRAs) constituem uma importante ferramenta para realização de estudos que envolvam infertilidade, desenvolvimento de contraceptivos, gestação e desenvolvimento fetal, preservação da fertilidade em pacientes com câncer, geração de modelos experimentais por meio de técnicas de edição gênica, entre outros. O objetivo dessa revisão é discutir as principais TRAs utilizadas em PNHs e suas aplicações. Dentre as técnicas mais utilizadas em PNHs, podem-se citar colheita e criopreservação de sêmen, monitoramento do ciclo ovariano, estimulação ovariana controlada e aspiração de folículos ovarianos, fecundação in vitro, injeção intracitoplasmática de espermatozoides, inseminação artificial, microinjeção para injeção gênica, biopsia embrionária, criopreservação de embriões, transferência de embriões, diagnóstico de gestação, enxerto de gônadas e clonagem. Os estudos apresentados nesta revisão mostram a evolução das TRAs e suas diferentes aplicações. Particularmente, os estudos de edição gênica e clonagem representam um grande avanço na utilização combinada de diversas TRAs para geração de modelos biomédicos para doenças humanas, demostrando o papel dessas técnicas para avanços científicos no que diz respeito à saúde humana.

Nonhuman Primates (NHPs) are considered important models for biomedical studies due to their high biological proximity with humans. The Assisted Reproductive Technologies (ARTs) represent an important tool to perform studies related to infertility, development of contraceptives, gestation and fetal development, fertility preservation in cancer patients, generation of experimental models through gene editing techniques, among others. The objective of this review is to discuss the main ARTs used in NHPs and their application. Among the most used techniques in NHPs, we can include collection and cryopreservation of semen, ovarian cycle monitoring, controlled ovarian stimulation and follicle aspiration, in vitro fertilization, intracytoplasmic sperm injection, artificial insemination, microinjections for gene editing, embryo biopsy, embryo cryopreservation, embryo transfer, pregnancy diagnosis, grafting of gonadal tissue, and cloning. The studies cited in this review illustrate the evolution of the ARTs and their applications. The gene editing and cloning studies, in particular, represent the great advancements on the combined use of several different ARTs for the generation of biomedical models for human diseases, demonstrating the role of these techniques in the scientific advancement with regards to human health.

Different times to perform timed artificial insemination when using a P4/E2/eCG-based protocol in buffalo / Momentos diferentes para executar a inseminação artificial em tempo fixo utilizando o protocolo à base de P4/E2/eCG em búfalas

The aim of this study was to evaluate different times for timed artificial insemination (TAI) in buffalo submitted to a P4/E2/eCG-based protocol. In this study, 204 buffaloes were distributed into one of two groups (TAI56, n=103 and TAI64, n=101). At a random stage of the oestrous cycle (Day 0 = D0), in the morning (TAI56, a.m.) or afternoon (TAI64, p.m.), buffaloes received an intravaginal progesterone device (P4; 1.0 g) plus EB (2.0 mg i.m.). On D9 a.m. (TAI56) or p.m. (TAI64), the P4 was removed and buffaloes received PGF2a (0.53 mg i.m. sodium cloprostenol) and eCG (400 IU i.m.). On D10 a.m. (TAI56) or p.m. (TAI64), 24 h after P4 removal, buffaloes were treated with EB (1.0 mg i.m.). Buffaloes from TAI56 and TAI64 were inseminated 56 and 64 h after P4 removal (D11, p.m. and D12, a.m., respectively). Ultrasound examinations were performed on D0 to ascertain ovarian follicular status, at TAI to measure the diameter of the dominant follicle (DF) and D42 for pregnancy diagnosis. The statistical analysis was performed using the GLIMMIX procedure of SAS®. There was no difference between TAI56 and TAI64 for the diameter of the DF at TAI and the pregnancy per TAI. It was concluded that TAI 56 or 64 h after P4 removal did not affect fertility in buffaloes submitted to the induction of ovulation with EB. The present research supports that is possible to perform TAI at any time throughout the day in buffalo synchronized during the non-breeding season.(AU)

O objetivo deste estudo foi avaliar diferentes momentos para a realização da IATF em búfalas submetidas a um protocolo à base de P4/E2/eCG. Neste estudo, 204 búfalas foram distribuídas em um de dois grupos (IATF56, n=103 e IATF64, n=101). Em estágio aleatório do ciclo estral (Dia 0 = D0), pela manhã (IATF56, manhã) ou pela tarde (IATF64, tarde), as búfalas receberam um dispositivo intravaginal de progesterona (P4; 1,0 g) e BE (2,0 mg i.m.). No D9 pela manhã (IATF56) ou pela tarde (IATF64), a P4 foi removida e as búfalas receberam PGF2a (0,53 mg i.m. cloprostenol sódico) e eCG (400 UI i.m.). No D10 pela manhã (IATF56) ou pela tarde (IATF64), 24 h após a remoção da P4, as búfalas foram tratadas com BE (1,0 mg i.m.). As búfalas dos grupos IATF56 e IATF64 foram inseminadas 56 e 64 h após a remoção da P4 (D11, pela tarde e D12, pela manhã, respectivamente). Avaliações ultrassonográficas foram realizadas no D0 para verificar o status folicular ovariano, na IATF para medir o diâmetro do folículo dominante (FD) e no D42 para o diagnóstico de gestação. A análise estatística foi realizada utilizando o procedimento GLIMMIX do SAS®. Não houve diferença entre os grupos IATF56 e IATF64 no diâmetro do FD na IATF e na prenhez por IATF. Conclui-se que a IATF 56 ou 64 h após a remoção da P4 não afeta a fertilidade de búfalas submetidas à indução da ovulação com BE. A presente pesquisa evidencia que é possível realizar a IATF durante todo o dia em búfalas sincronizadas durante a estação reprodutiva desfavorável.(AU)

Effect of the subdose of human chorionic gonadotropin applied in the Hou Hai acupoint on ovulation induction in mares / [Efeito da subdose de gonadotrofina coriônica humana aplicada no acuponto Hou Hai sobre a indução da ovulação em éguas]

The objective of this study was to evaluate the effects of an hCG sub dose applied at the Hou Hai acupoint on corpus luteum (CL) quality and ovulation induction in mares. Fifteen crossbred mares were distributed in randomized blocks and used in three periods with each period employed as the blocking factor in three treatments: T1 = 1500 IU of hCG via intravenous (IV); T2 = 450 IU of hCG applied at the false acupoint (IV); and T3 = 450 IU of hCG applied at the Hou Hai acupoint. Mean diameter of the CL, serum concentration of progesterone (P4), vascularization of the pre-ovulatory follicle and CL were evaluated. Females administered 450 IU of hCG at the Hou Hai acupoint exhibited greater ovulation rates (33.33%) 48h after induction; The minimum number of colored pixel (NCP) of the pre-ovulatory follicle of control females was superior (40.33) to that of mares administered 450 IU of hCG IV at the false acupoint (36.84) and similar to that of those administered hCG at the Hou Hai acupoint (39.31). Further, moderately positive correlations were found between the CL diameter and the P4 concentration on D8 (P<0.05). IV administration of 450 IU of hCG or at the Hou Hai acupoint was efficient at inducing ovulation and ensuring the quality of CL in mares.(AU)

O objetivo foi avaliar os efeitos de uma subdose de hCG aplicada no acuponto Hou Hai na qualidade do corpo lúteo (CL) e na indução da ovulação em éguas. Quinze éguas mestiças foram distribuídas em blocos ao acaso, sendo o período utilizado como fator de blocagem, em: T1 = 1500 UI de hCG por via intravenosa (IV); T2 = 450 UI de hCG aplicado no falso acuponto (IV) e T3 = 450 UI de hCG aplicada no acuponto Hou Hai. Avaliou-se diâmetro médio do CL, concentração sérica de progesterona (P4), vascularização do folículo pré-ovulatório e do CL. As fêmeas que receberam 450 UI de hCG no acuponto Hou Hai apresentaram maiores taxas de ovulação (33,33%) 48h após a indução. O número de pixels coloridos (NPC) mínimo do folículo pré-ovulatório das fêmeas do grupo controle foi superior (40,33) ao das éguas que receberam 450 UI de hCG IV no falso acuponto (36,84) e semelhante ao das éguas que receberam hCG no acuponto Hou Hai (39,31); correlações moderadamente positivas foram encontradas entre o diâmetro do CL e a concentração de P4, ambos no D8 (P <0,05). A administração IV de 450 UI de hCG ou no acuponto Hou Hai foi eficiente na indução da ovulação e na garantia da qualidade do CL nas éguas.(AU)

Efeito da somatotropina bovina recombinante (rbST) na produção in vivo e na maturação in vitro de oócitos bovinos da raça Sindi / Effect of recombinant bovine somatotropin (rbST) on the in vivo production and in vitro maturation of bovine oocytes of the Sindi breed

A fim de avaliar o efeito de diferentes doses da rbST sobre a dinâmica folicular, a produção e a maturação in vitro de oócitos, 20 vacas Sindi, divididas em três grupos, receberam um dispositivo de progesterona intravaginal, estradiol e PGF2α, além de 2mL de solução salina (grupo controle), 250 (grupo rbST 250) ou 500mg de rbST (grupo rbST 500). Cinco dias depois, realizou-se a ovum pick up, e os complexos cumulus-oócitos (CCOs) recuperados foram selecionados, classificados e maturados in vitro. Os dados de contagem foram comparados pelo procedimento glht (General Linear Hypothesis Test), e os dados em porcentagem foram submetidos ao qui-quadrado, no programa estatístico R, onde as diferenças foram consideradas significativas quando P<0,05. Não houve diferença (P>0,05) entre os grupos quanto à quantidade de folículos e à taxa de maturação. Os grupos rbST 250 e rbST 500 foram significativamente superiores (P<0,05) ao grupo controle em relação ao número de folículos grandes (0,42±0,20 vs. 0). O grupo rbST 500 apresentou maior (P<0,05) porcentagem de oócitos viáveis (91,52%) do que os grupos controle (67,85%) e rbST 250 (53,33%). A rbST aumenta o número de folículos grandes, e 500mg de rbST aumentam a porcentagem de oócitos viáveis em vacas Sindi.(AU)

In order to evaluate the effect of different doses of rbST on the follicular dynamics, production, and in vitro maturation of oocytes, 20 Sindhi cows were divided into three groups, receiving an intravaginal progesterone device, estradiol and PGF2α, and 2mL of solution saline (Control Group), 250 (rbST 250 Group) or 500mg rbST (rbST 500 Group). Five days later, the ovum pick up was performed, and the cumulus-oocyte (CCO) complexes recovered were selected, classified, and matured in vitro. The counting data were compared by the glht (General Linear Hypothesis Test) procedure, and the percentage data were submitted to Qui- square, in the statistical program R, where differences were considered significant when P< 0.05. There was no difference (P> 0.05) between the groups regarding follicle quantity and maturation rate. The rbST 250 and rbST 500 groups were significantly higher (P< 0.05) than the Control group in relation to the number of large follicles (0.42±0.20 versus 0). The rbST 500 group presented higher (P< 0.05) percentage of viable oocytes (91.52%) than the Control (67.85%) and rbST 250 (53.33%) groups. rbST increases the number of large follicles and 500mg rbST increases the percentage of viable oocytes in Sindhi cows.(AU)

Efeito da somatotropina bovina recombinante (rbST) na produção in vivo e na maturação in vitro de oócitos bovinos da raça Sindi / Effect of recombinant bovine somatotropin (rbST) on the in vivo production and in vitro maturation of bovine oocytes of the Sindi breed

A fim de avaliar o efeito de diferentes doses da rbST sobre a dinâmica folicular, a produção e a maturação in vitro de oócitos, 20 vacas Sindi, divididas em três grupos, receberam um dispositivo de progesterona intravaginal, estradiol e PGF2α, além de 2mL de solução salina (grupo controle), 250 (grupo rbST 250) ou 500mg de rbST (grupo rbST 500). Cinco dias depois, realizou-se a ovum pick up, e os complexos cumulus-oócitos (CCOs) recuperados foram selecionados, classificados e maturados in vitro. Os dados de contagem foram comparados pelo procedimento glht (General Linear Hypothesis Test), e os dados em porcentagem foram submetidos ao qui-quadrado, no programa estatístico R, onde as diferenças foram consideradas significativas quando P<0,05. Não houve diferença (P>0,05) entre os grupos quanto à quantidade de folículos e à taxa de maturação. Os grupos rbST 250 e rbST 500 foram significativamente superiores (P<0,05) ao grupo controle em relação ao número de folículos grandes (0,42±0,20 vs. 0). O grupo rbST 500 apresentou maior (P<0,05) porcentagem de oócitos viáveis (91,52%) do que os grupos controle (67,85%) e rbST 250 (53,33%). A rbST aumenta o número de folículos grandes, e 500mg de rbST aumentam a porcentagem de oócitos viáveis em vacas Sindi.(AU)

In order to evaluate the effect of different doses of rbST on the follicular dynamics, production, and in vitro maturation of oocytes, 20 Sindhi cows were divided into three groups, receiving an intravaginal progesterone device, estradiol and PGF2α, and 2mL of solution saline (Control Group), 250 (rbST 250 Group) or 500mg rbST (rbST 500 Group). Five days later, the ovum pick up was performed, and the cumulus-oocyte (CCO) complexes recovered were selected, classified, and matured in vitro. The counting data were compared by the glht (General Linear Hypothesis Test) procedure, and the percentage data were submitted to Qui- square, in the statistical program R, where differences were considered significant when P< 0.05. There was no difference (P> 0.05) between the groups regarding follicle quantity and maturation rate. The rbST 250 and rbST 500 groups were significantly higher (P< 0.05) than the Control group in relation to the number of large follicles (0.42±0.20 versus 0). The rbST 500 group presented higher (P< 0.05) percentage of viable oocytes (91.52%) than the Control (67.85%) and rbST 250 (53.33%) groups. rbST increases the number of large follicles and 500mg rbST increases the percentage of viable oocytes in Sindhi cows.(AU)

Impact of hypotensive action of angiotensin converting enzyme inhibitor on ovarian-intraovarian blood flow and follicles development in goats hormonally stimulated with repeated FSH-ECG treatment

Background: Recent evidence shows that the renin-angiotensin system (RAS) participates in important reproductiveprocesses, such as steroidogenesis, folliculogenesis, oocyte maturation and ovulation. Several studies have proposed touse an angiotensin-converting enzyme (ACE) as a RAS modulator, aiming to improve reproductive efficiency, however,the presence of the main components of this system in reproductive tissues still need to be further investigated, since thephysiological functions seem to be species-specific. The aim of this study was to assess the impact of enalapril-maleate,an ACE inhibitor, during repeated gonadotropins treatment on ovarian blood flow and follicular development in goats.Materials, Methods & Results: Twenty Anglo-Nubian cross-bred goats were equally grouped according to parity (n= 10/group): nulliparous and multiparous parity. In each group, five animals were randomly selected to receive 0.4 mg.kg-1 ofenalapril-maleate during 11 days of estrus synchronization and gonadotropins treatments. The other animals received thesame volume of saline solution. Estrus synchronization of all goats was made by intramuscular ad-ministration of PGF2αanalog, followed 48 h later by intravaginal insertion of a controlled internal drug release device. Forty-eight h after devicewithdrawal, a single dose of 60 mg of FSH plus 300 UI of eCG was administered and repeated every 4 days to complete 3treatments. Transrectal ultrasonography was performed using pulsed and color Doppler to evaluate Doppler velocimetricsparameters of the ovarian artery and intraovarian blood flow, respec-tively, and B-mode real-time ultrasound scanner toevaluate the follicular development. In the females treated with enalapril-maleate was observed a significant reduction ofsystolic and diastolic peak, without difference according to parity. In addition, in the third session of hor-monal stimulation,only the groups (nulliparous and multiparous) not treated with...(AU)

Impact of hypotensive action of angiotensin converting enzyme inhibitor on ovarian-intraovarian blood flow and follicles development in goats hormonally stimulated with repeated FSH-ECG treatment

Background: Recent evidence shows that the renin-angiotensin system (RAS) participates in important reproductiveprocesses, such as steroidogenesis, folliculogenesis, oocyte maturation and ovulation. Several studies have proposed touse an angiotensin-converting enzyme (ACE) as a RAS modulator, aiming to improve reproductive efficiency, however,the presence of the main components of this system in reproductive tissues still need to be further investigated, since thephysiological functions seem to be species-specific. The aim of this study was to assess the impact of enalapril-maleate,an ACE inhibitor, during repeated gonadotropins treatment on ovarian blood flow and follicular development in goats.Materials, Methods & Results: Twenty Anglo-Nubian cross-bred goats were equally grouped according to parity (n= 10/group): nulliparous and multiparous parity. In each group, five animals were randomly selected to receive 0.4 mg.kg-1 ofenalapril-maleate during 11 days of estrus synchronization and gonadotropins treatments. The other animals received thesame volume of saline solution. Estrus synchronization of all goats was made by intramuscular ad-ministration of PGF2αanalog, followed 48 h later by intravaginal insertion of a controlled internal drug release device. Forty-eight h after devicewithdrawal, a single dose of 60 mg of FSH plus 300 UI of eCG was administered and repeated every 4 days to complete 3treatments. Transrectal ultrasonography was performed using pulsed and color Doppler to evaluate Doppler velocimetricsparameters of the ovarian artery and intraovarian blood flow, respec-tively, and B-mode real-time ultrasound scanner toevaluate the follicular development. In the females treated with enalapril-maleate was observed a significant reduction ofsystolic and diastolic peak, without difference according to parity. In addition, in the third session of hor-monal stimulation,only the groups (nulliparous and multiparous) not treated with...

Ovariosalpingohysterectomy technique adapted in bitches (Canis familiaris): advantages and limitations

Background: The ovariosalpingohysterectomy (OSH) is one of the most performed surgeries in bitches often used in population control. Surgical techniques that decrease the chances of operative complications and cause less nociceptive stimulation and acute pain to the patient are highly sought after by veterinarians. We evaluated the inverted OSH technique (IT), which, after celiotomy, begins with the ligature execution, transection of the uterine body and subsequent ligation and ovarian disinsertion. The purpose of this investigation was to analyze aspects of IT execution in bitches, such as visceral manipulation, access to the uterus and ovaries, and surgical time compared to the traditional technique. Materials, Methods & Results: Inverted OSH was compared to the so-called traditional OSH technique, characterized by the initial removal of the ovaries followed by uterine section. The OSH techniques were performed in 24 healthy animals, with a body condition score of up to six (on a nine-point scale) in dogs aged between seven months and five years. All dogs were from the Birth Control Program of Dogs and Cats of the UFRRJ and were distributed into two groups: traditional technique (TT) and inverted technique (IT). Surgeries and anesthesia were carried out by the same veterinarian crew (surgeon, surgical assistant, and anesthesiologist). OSH techniques were evaluated by the surgeon and surgical assistant using semiquantitative analysis (multiple-choice questionnaire with closed questions that pointed scores related to the ease of uterine and ovarian manipulation, as well as to the level of manipulation of the intestinal and urinary vesicle) and qualitative descriptive methods (report of techniques with the opinion of surgeons and an external evaluator-veterinarian surgeon who attended surgeries). Also, the total surgical time and the indication of a positive analgesic response according to changes in the vital parameters observed by the anesthesiologist during specific moments of the operation were

Ovariosalpingohysterectomy technique adapted in bitches (Canis familiaris): advantages and limitations

Background: The ovariosalpingohysterectomy (OSH) is one of the most performed surgeries in bitches often used in population control. Surgical techniques that decrease the chances of operative complications and cause less nociceptive stimulation and acute pain to the patient are highly sought after by veterinarians. We evaluated the inverted OSH technique (IT), which, after celiotomy, begins with the ligature execution, transection of the uterine body and subsequent ligation and ovarian disinsertion. The purpose of this investigation was to analyze aspects of IT execution in bitches, such as visceral manipulation, access to the uterus and ovaries, and surgical time compared to the traditional technique. Materials, Methods & Results: Inverted OSH was compared to the so-called traditional OSH technique, characterized by the initial removal of the ovaries followed by uterine section. The OSH techniques were performed in 24 healthy animals, with a body condition score of up to six (on a nine-point scale) in dogs aged between seven months and five years. All dogs were from the Birth Control Program of Dogs and Cats of the UFRRJ and were distributed into two groups: traditional technique (TT) and inverted technique (IT). Surgeries and anesthesia were carried out by the same veterinarian crew (surgeon, surgical assistant, and anesthesiologist). OSH techniques were evaluated by the surgeon and surgical assistant using semiquantitative analysis (multiple-choice questionnaire with closed questions that pointed scores related to the ease of uterine and ovarian manipulation, as well as to the level of manipulation of the intestinal and urinary vesicle) and qualitative descriptive methods (report of techniques with the opinion of surgeons and an external evaluator-veterinarian surgeon who attended surgeries). Also, the total surgical time and the indication of a positive analgesic response according to changes in the vital parameters observed by the anesthesiologist during specific moments of the operation were…(AU)

Evaluation of stemness marker expression in bovine ovarian granulosa cells

The objective of this study was to assess the stemness marker expressions (Oct4, Nanog, and Sox2) of granulosa cells (GCs) collected from bovine ovarian follicles and in vitro expansion. The single bovine ovarian follicles were isolated and categorized into 4 groups according to their diameter including group A (4 mm). Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and immunostaining were applied to evaluate the stemness marker expression of bovine GCs from ovarian follicles. We also estimated the stemness marker transcript expressions of GCs during in vitro expression by qRT-PCR. qRT-PCR analysis demonstrated that fresh GCs from bovine ovarian follicles expressed the stemness markers (Oct4, Nanog, Sox2). These markers were down-regulated during antral stage follicular development. We also estimated stemness marker transcript expressions of GCs which were isolated and in vitro expanded from ovarian follicles of group A. The qRT-PCR results showed that Oct4 and Sox2 transcript expressions were reduced during in vitro expansion while Nanog transcript was not expressed.

Evaluation of stemness marker expression in bovine ovarian granulosa cells

The objective of this study was to assess the stemness marker expressions (Oct4, Nanog, and Sox2) of granulosa cells (GCs) collected from bovine ovarian follicles and in vitro expansion. The single bovine ovarian follicles were isolated and categorized into 4 groups according to their diameter including group A (4 mm). Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and immunostaining were applied to evaluate the stemness marker expression of bovine GCs from ovarian follicles. We also estimated the stemness marker transcript expressions of GCs during in vitro expression by qRT-PCR. qRT-PCR analysis demonstrated that fresh GCs from bovine ovarian follicles expressed the stemness markers (Oct4, Nanog, Sox2). These markers were down-regulated during antral stage follicular development. We also estimated stemness marker transcript expressions of GCs which were isolated and in vitro expanded from ovarian follicles of group A. The qRT-PCR results showed that Oct4 and Sox2 transcript expressions were reduced during in vitro expansion while Nanog transcript was not expressed.(AU)

Hormônios utilizados na indução da ovulação em bovinos Artigo de revisão / Hormones used as ovulation inducers in cattle A review

Diversos hormônios podem ser utilizados em protocolos que visam otimizar biotécnicas reprodutivas como a inseminação artificial (IA) e inseminação artificial em tempo fixo (IATF), que exigem controle preciso do ciclo estral e da ovulação. Alguns hormônios possuem ação central no eixo hipotalâmico-hipofisário, como o hormônio liberador de gonadotrofinas (GnRH) e os ésteres de estradiolcomo o benzoato (BE) e o cipionato de estradiol (CE), enquanto outros como a gonadotrofina coriônica humana (hCG) e o hormônio luteinizante (LH) apresentam ação local, a nível ovariano. Atualmente os protocolos mais utilizados para indução da ovulação utilizam GnRH e estrógenos. Recentemente, foi demonstrado que as prostaglandinas possuem efeitos positivos na indução do processo ovulatório, mas seu mecanismo de ação não está totalmente esclarecido. A presente revisão tem por objetivo abordar os principais indutores da ovulação utilizados em protocolos para controle do ciclo estral em bovinos, relatando o período de ocorrência das ovulações após a sua aplicação.(AU)

Several hormones may be used in protocols aimed to optimize reproductive biotechniques such as artificial insemination (AI) and fixed-timed artificial insemination (FTAI) which require precise control of the estrous cycle and the ovulation. Some hormones act on the hypothalamic-pituitary axis, such as the gonadotrophin releasing hormone (GnRH) and estradiol esters such as estradiol benzoate (EB) and cypionate (EC), whereas others act directly on the ovaries, such as human chorionic gonadotrophin (hCG) and luteinizing hormone (LH). Currently, the most commonly used protocols for ovulation induction use GnRH or estrogen. Prostaglandins have recently been shown to have positive effects on induction of the ovulatory process, but their mechanism of action is not fully understood. The present review aims to address the main ovulation inducers used in protocols to control the estrous cycle in cattle, emphasizing the period between their administration and the occurrence of ovulation.(AU)

Hormônios utilizados na indução da ovulação em bovinos – Artigo de revisão / Hormones used as ovulation inducers in cattle – A review

Diversos hormônios podem ser utilizados em protocolos que visam otimizar biotécnicas reprodutivas como a inseminação artificial (IA) e inseminação artificial em tempo fixo (IATF), que exigem controle preciso do ciclo estral e da ovulação. Alguns hormônios possuem ação central no eixo hipotalâmico-hipofisário, como o hormônio liberador de gonadotrofinas (GnRH) e os ésteres de estradiolcomo o benzoato (BE) e o cipionato de estradiol (CE), enquanto outros como a gonadotrofina coriônica humana (hCG) e o hormônio luteinizante (LH) apresentam ação local, a nível ovariano. Atualmente os protocolos mais utilizados para indução da ovulação utilizam GnRH e estrógenos. Recentemente, foi demonstrado que as prostaglandinas possuem efeitos positivos na indução do processo ovulatório, mas seu mecanismo de ação não está totalmente esclarecido. A presente revisão tem por objetivo abordar os principais indutores da ovulação utilizados em protocolos para controle do ciclo estral em bovinos, relatando o período de ocorrência das ovulações após a sua aplicação.

Several hormones may be used in protocols aimed to optimize reproductive biotechniques such as artificial insemination (AI) and fixed-timed artificial insemination (FTAI) which require precise control of the estrous cycle and the ovulation. Some hormones act on the hypothalamic-pituitary axis, such as the gonadotrophin releasing hormone (GnRH) and estradiol esters such as estradiol benzoate (EB) and cypionate (EC), whereas others act directly on the ovaries, such as human chorionic gonadotrophin (hCG) and luteinizing hormone (LH). Currently, the most commonly used protocols for ovulation induction use GnRH or estrogen. Prostaglandins have recently been shown to have positive effects on induction of the ovulatory process, but their mechanism of action is not fully understood. The present review aims to address the main ovulation inducers used in protocols to control the estrous cycle in cattle, emphasizing the period between their administration and the occurrence of ovulation.