Oxidative activity of corpus luteum and ovarian parenchyma in Bos taurus indicus heifers

Abstract The aim of this study was to evaluate the oxidative stress in ovaries and corpus luteum (CL) of Bos taurus indicus females and the oxidant effect of CL in ovarian tissues in regions near, intermediate, or distant from it. Ovaries (n=12) of Nelore heifers (n=6) were collected from a slaughterhouse and fragmented. Experiment 1, each ovary was obtained from three fragments, resulting in 18 fragments of ovaries with CL (OV+CL) and another 18 fragments of ovaries without CL (OV-CL). Three fragments were generated from CL, totaling 18 CL fragments. In experiment 2, the ovarian fragments were removed from specific regions near, intermediate, or distant from the CL. All the fragments were placed in Eppendorf-type microtubes (1 mL), kept in a thermal container at 4 ºC, and then stored in a -80 ºC freezer for analysis of oxidative stress (TBARS and NBT) and antioxidant potential (FRAP and ABTS). In the antioxidant activity analysis, luteal tissues showed more antioxidant activity than ovarian tissue (FRAP = P < 0.0001; ABTS = P < 0.02). In the oxidative stress analysis, CL had lower levels of reactive oxygen species (ROS; TBARS = P < 0.03; NBT = P < 0.0001) than ovarian tissues. There was no difference in antioxidant activity and oxidative stress between the fragments obtained from different regions (OV+CL versus OV-CL; P > 0.05). The presence of CL in the ovaries of Bos taurus indicus females did not influence the oxidative stress or antioxidant potential of the gonad. Thus, the removal of ovarian fragments with or without the presence of CL indicates that biotechnologies such as in vitro follicle cultivation is possible.

Ovarian papillary carcinoma in a Mongolian gerbil (Meriones unguiculatus)

Neoplasms are among the most impacting disease diagnoses in veterinary medicine and have become increasingly common due to the greater longevity of animals as living conditions improved. The Mongolian gerbil is a small rodent species that has become popular recently. In these animals, the occurrence of neoplastic processes is relatively common, mainly tumors of the ventral gland in males and ovarian tumors in females. This work aims to report an ovarian tumor in a Mongolian gerbil Meriones unguiculatus Milne-Edwards 1867 (Rodentia, Muridae). At the initial presentation, the animal had dyspnea, prostration, and increased abdominal volume in the topography of the right ovary of approximately 2 cm. The animal was submitted to exploratory laparotomy because of the emergency nature of the case and the owners' refusal of additional exams due to financial restrictions. Thus, an ovariohysterectomy was performed, followed by a histopathological examination. The histopathology revealed an ovarian papillary carcinoma affecting both ovaries and cystic endometrial hyperplasia. With surgical removal and drainage of the thoracic fluid, the animal showed good recovery, with general improvement and return to regular activity, with a life expectancy of two years. Currently, the demand for specialized veterinarians for unconventional pets is increasing. This condition allows owners to raise their animals more properly, favoring greater longevity. Knowledge about the prevalence and incidence of diseases in different species is of enormous relevance in establishing the appropriate therapy, improving life quality, and increasing life expectancy in animals' lives.(AU)

Oxidative activity of corpus luteum and ovarian parenchyma in Bos taurus indicus heifers

The aim of this study was to evaluate the oxidative stress in ovaries and corpus luteum (CL) of Bos taurus indicus females and the oxidant effect of CL in ovarian tissues in regions near, intermediate, or distant from it. Ovaries (n=12) of Nelore heifers (n=6) were collected from a slaughterhouse and fragmented. Experiment 1, each ovary was obtained from three fragments, resulting in 18 fragments of ovaries with CL (OV+CL) and another 18 fragments of ovaries without CL (OV-CL). Three fragments were generated from CL, totaling 18 CL fragments. In experiment 2, the ovarian fragments were removed from specific regions near, intermediate, or distant from the CL. All the fragments were placed in Eppendorf-type microtubes (1 mL), kept in a thermal container at 4 ºC, and then stored in a -80 ºC freezer for analysis of oxidative stress (TBARS and NBT) and antioxidant potential (FRAP and ABTS). In the antioxidant activity analysis, luteal tissues showed more antioxidant activity than ovarian tissue (FRAP = P < 0.0001; ABTS = P < 0.02). In the oxidative stress analysis, CL had lower levels of reactive oxygen species (ROS; TBARS = P < 0.03; NBT = P < 0.0001) than ovarian tissues. There was no difference in antioxidant activity and oxidative stress between the fragments obtained from different regions (OV+CL versus OV-CL; P > 0.05). The presence of CL in the ovaries of Bos taurus indicus females did not influence the oxidative stress or antioxidant potential of the gonad. Thus, the removal of ovarian fragments with or without the presence of CL indicates that biotechnologies such as in vitro follicle cultivation is possible.(AU)

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)

Influência das espécies reativas de oxigênio durante o cultivo in vitro de oócitos e folículos ovarianos de mamíferos domésticos / Influence of reactive oxygen species during in vitro culture of ovarian oocytes and follicles of domestic mammals

Sistemas de cultivo in vitro de folículos pré-antrais e de complexos cumulus-oócitos (CCOs) se tornaram uma poderosa ferramenta capaz de subsidiar diversas biotécnicas reprodutivas, bem como possibilitar estudos do efeito de substâncias sobre a dinâmica folicular. No entanto, esses sistemas podem resultar em estresse oxidativo e na diminuição da proteção antioxidante das células, distúrbio associado a altas taxas de morte celular durante o cultivo in vitro. Para contornar esses efeitos adversos, a adição de substâncias antioxidantes aos meios de cultivo tem sido proposta. Abrangendo diferentes classes e mecanismos de ação, compostos antioxidantes têm por função interferir no processo de oxidação para inibir ou retardar o dano oxidativo causado pelos radicais livres às biomoléculas. Além de antioxidantes que têm sido rotineiramente utilizados com esse propósito, recentemente, substâncias alternativas de origem natural como extratos vegetais e óleos essenciais têm ganhado destaque. Dessa forma, diante da influência do estresse oxidativo e da importância do uso de antioxidantes no cultivo celular, a presente revisão objetiva abordar os principais mecanismos de síntese e atuação dos radicais livres bem como o papel dos antioxidantes em protocolos de cultivo in vitro de folículos ovarianos e de CCOs de animais domésticos.(AU)

In vitro culture systems for preantral follicles and cumulus-oocyte complexes (COCs) have become a powerful tool capable of subsidizing several reproductive biotechniques, as well as enabling studies of the effect of substances on follicular dynamics. However, these systems can favor oxidative stress and decrease the antioxidant protection of cells, a disorder associated with high rates of cell death during in vitro culture. To overcome these adverse effects, the addition of antioxidant substances to the culture media has been proposed. Covering different classes and mechanisms of action, these antioxidant compounds have the function of interfering in the oxidation process to inhibit or delay the oxidative damage caused by free radicals to biomolecules. In addition to antioxidants that have been commonly used for this purpose, recently, alternative substances of natural origin such as plant extracts and essential oils have gained prominence. Thus, given the influence of oxidative stress and the importance of using antioxidants in cell culture, this review aims to address the main mechanisms of synthesis and action of free radicals as well as the role of antioxidants in in vitro protocols for ovarian follicles and COCs in domestic animals.(AU)

Protective effect of kaempferol against cisplatin-induced acute ovarian damage in a mouse model / [Efeito protetor do kaempferol contra o dano ovariano agudo induzido pela cisplatina em um modelo murino]

The flavonoid kaempferol has attracted research attention as a potential adjuvant during chemotherapy. This study aimed to evaluate the protective effects of kaempferol against ovarian damage in cisplatin-treated mice. Two groups of mice received saline solution (intraperitoneal injection [i.p.]; control) or a single dose of cisplatin (5 mg/kg body weight, i.p.). Moreover, two other mice groups were pretreated with kaempferol (1 or 10 mg/kg body weight, i.p.) 30 min before of the cisplatin administration. Thereafter, their ovaries were harvested and subjected to histological (follicular morphology and activation) and fluorescence (reactive oxygen species [ROS] production, glutathione [GSH] concentration, and mitochondrial activity) analyses. Compared with cisplatin treatment alone, pretreatment with 1 mg/kg kaempferol maintained normal follicular morphology, reduced ROS production and mitochondrial damage, and enhanced GSH concentration. However, pretreatment with 10 mg/kg kaempferol did not prevent cisplatin-induced damage. The rate of primordial follicle activation was greater in mice pretreated with 1 mg/kg kaempferol than in the other treatment groups. In conclusion, pretreatment with 1 mg/kg kaempferol prevents cisplatin-induced ovarian damage and stimulates primordial follicle activation in mice.

O flavonoide kaempferol tem atraído a atenção como um potencial adjuvante durante a quimioterapia. O presente estudo objetivou avaliar os efeitos do kaempferol contra os danos ovarianos em camundongos tratados com cisplatina. Fêmeas de camundongos receberam solução salina (injeção intraperitoneal [ip]; controle) ou uma dose única de cisplatina (5 mg/kg, ip) ou foram pré-tratadas com kaempferol (1 ou 10 mg/kg, ip) 30 min antes da administração de cisplatina. Os ovários foram recuperados e destinados para as análises histológicas (morfologia e ativação folicular) e de fluorescência (produção de espécies reativas de oxigênio [ERO], concentração de glutationa [GSH] e atividade mitocondrial). Em comparação ao tratamento apenas com cisplatina, o pré-tratamento com 1 mg/kg de kaempferol manteve a morfologia folicular normal, reduziu a produção de ERO, bem como os danos mitocondriais, e aumentou a concentração de GSH. Entretanto, o pré-tratamento com 10 mg/kg de kaempferol não preveniu os danos induzidos pela cisplatina. A taxa de ativação do folículo primordial foi maior em camundongos pré-tratados com 1 mg/kg de kaempferol do que nos outros grupos experimentais. Em conclusão, o pré-tratamento com 1 mg/kg de kaempferol previne o dano ovariano induzido pela cisplatina e estimula a ativação do folículo primordial em camundongos.

Impacts of trace element supplementation on productive/reproductive postpartum performances of grazing dairy heifers from volcanic soils

This study has been designed to evaluate the effect of trace elements (TE) on the reproductive and productive performances of postpartum Holstein Friesian heifers, fed on pasture with origin on volcanic soils, poor in TE. Twenty-six heifers pregnant were divided into two groups: experimental (EG) and control (CG) groups (n=13, each group). For animals belonging to the EG, two intra-ruminal capsules with TE were administrated 60 days before partum, while in the CG, no boluses were administered. All animals' blood was collected weekly to assess progesterone levels by the ELFA technique for 11 weeks after partum. TE were evaluated on blood by AAS when the experience started, on the day of delivery, and after 60 days. Before calving, no statistical differences were observed between groups for the trace elements, although it has been noticed that heifers had deficiencies in Selenium, Copper, and Iodine. On the calving day and 60 days after, a statistical increase (p<0.05) in serum Copper and Selenium was observed in the animals belonging to the EG. For the other TE, no statistical differences were observed. Concerning reproductive characteristics, the EG, at five weeks postpartum, 70% of the cows were cyclic, while in the CG in the same period, 33% of animals showed signs of ovarian activity. At the level of productive parameters, no differences were observed between groups. The results obtained by the present study allow concluding that, under our experimental conditions, the administration of trace elements, in addition to reducing postpartum anestrus, increases the quality of the corpus luteum in the postpartum period of heifers.

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)

Viabilidade ovariana com o uso do extrato de semente de uva: uma revisão sistemática / Ovarian viability with the use of grape seed extract: a systematic review / Viabilidad ovárica con extracto de semilla de uva: una revisión sistemática

El objetivo fue analisar sistemáticamente la literatura para verificar la influencia del extracto de semilla de uva como factor antioxidante en el tratamiento de la salud ovárica. Por medio de búsqueda y selección de literatura en artículos publicados en inglés en las bases de datos Lilacs, PubMed, SciELO, Science Direct / Elvesier y Google Scholar. Los descriptores utilizados fueron uva (uva) "AND" semilla (semilla) "AND" ovario (ovario) "OR" ovárico (ovario), con 9,100 artículos encontrados. Se realizaron lecturas de títulos, resúmenes y textos completos, 03 manuscritos cumplieron los criterios de inclusión. El uso de extracto de procianidina de semilla de uva y extracto de proantocianidina de semilla de uva obtuvo una reducción en ROS, mientras que se observó una reducción de LDL en el uso de extracto de semilla de uva. El extracto de semilla de uva puede ser beneficioso para la...

The objective was to review systematically the literature to verify the influence of grape seed extract as an antioxidant factor in the treatment of ovarian health by search and selection of literature in articles published in English in the Lilacs, PubMed, SciELO, Science Direct / Elvesier and Google Scholar databases. Descriptors used were grape (grape) AND seed (seed) AND ovary (ovary) OR ovarian (ovarian), with 9,100 articles found. Readings of titles, abstracts and full texts were performed, 03 manuscripts fulfilled the inclusion criteria. The use of grape seed procyanidin extract and grape seed proanthocyanidin extract obtained a reduction in ROS, while LDL reduction was observed in the use of grape seed extract. Conclusion: Grape seed extract can be beneficial for the viability of ovarian health, as it causes homeostasis regarding oxidative stress, however, further studies are necessary.

O objetivo foi examinar sistematicamente a literatura para verificar a influência do extrato de semente de uva como fator antioxidante no tratamento da saúde ovariana. por meio de busca e seleção da literatura em artigos publicados em língua inglesa nas bases de dados Lilacs, PubMed, SciELO, Science Direct/Elvesier e Google Acadêmico. Descritores utilizados foram grape (uva) AND seed (semente) AND ovary (ovário) OR ovarian (ovariano), sendo localizados 9.100 artigos. Realizadas leituras de títulos, resumos e textos completos, 03 manuscritos preencheram os critérios de inclusão. O uso do extrato de procianidina de semente de uva e do extrato proantocianidina de semente de uva obtiveram redução de ROS, quanto ao uso do extrato de semente de uva foi observado redução de LDL. O extrato de semente de uva pode ser benéfico para a viabilidade da saúde ovariana, pois causa homeostase a respeito do estresse oxidativo, no entanto, faz-se necessário estudos mais aprofundados.

Viabilidade ovariana com o uso do extrato de semente de uva: uma revisão sistemática / Ovarian viability with the use of grape seed extract: a systematic review / Viabilidad ovárica con extracto de semilla de uva: una revisión sistemática

El objetivo fue analisar sistemáticamente la literatura para verificar la influencia del extracto de semilla de uva como factor antioxidante en el tratamiento de la salud ovárica. Por medio de búsqueda y selección de literatura en artículos publicados en inglés en las bases de datos Lilacs, PubMed, SciELO, Science Direct / Elvesier y Google Scholar. Los descriptores utilizados fueron uva (uva) "AND" semilla (semilla) "AND" ovario (ovario) "OR" ovárico (ovario), con 9,100 artículos encontrados. Se realizaron lecturas de títulos, resúmenes y textos completos, 03 manuscritos cumplieron los criterios de inclusión. El uso de extracto de procianidina de semilla de uva y extracto de proantocianidina de semilla de uva obtuvo una reducción en ROS, mientras que se observó una reducción de LDL en el uso de extracto de semilla de uva. El extracto de semilla de uva puede ser beneficioso para la...(AU)

The objective was to review systematically the literature to verify the influence of grape seed extract as an antioxidant factor in the treatment of ovarian health by search and selection of literature in articles published in English in the Lilacs, PubMed, SciELO, Science Direct / Elvesier and Google Scholar databases. Descriptors used were grape (grape) AND seed (seed) AND ovary (ovary) OR ovarian (ovarian), with 9,100 articles found. Readings of titles, abstracts and full texts were performed, 03 manuscripts fulfilled the inclusion criteria. The use of grape seed procyanidin extract and grape seed proanthocyanidin extract obtained a reduction in ROS, while LDL reduction was observed in the use of grape seed extract. Conclusion: Grape seed extract can be beneficial for the viability of ovarian health, as it causes homeostasis regarding oxidative stress, however, further studies are necessary.(AU)

O objetivo foi examinar sistematicamente a literatura para verificar a influência do extrato de semente de uva como fator antioxidante no tratamento da saúde ovariana. por meio de busca e seleção da literatura em artigos publicados em língua inglesa nas bases de dados Lilacs, PubMed, SciELO, Science Direct/Elvesier e Google Acadêmico. Descritores utilizados foram grape (uva) AND seed (semente) AND ovary (ovário) OR ovarian (ovariano), sendo localizados 9.100 artigos. Realizadas leituras de títulos, resumos e textos completos, 03 manuscritos preencheram os critérios de inclusão. O uso do extrato de procianidina de semente de uva e do extrato proantocianidina de semente de uva obtiveram redução de ROS, quanto ao uso do extrato de semente de uva foi observado redução de LDL. O extrato de semente de uva pode ser benéfico para a viabilidade da saúde ovariana, pois causa homeostase a respeito do estresse oxidativo, no entanto, faz-se necessário estudos mais aprofundados.(AU)

Relationship between protective maternal behavior and some reproductive variables in zebu-type cows (Bos indicus)

To determine a possible relationship between protective maternal behavior and some reproductive variables in zebu cows, 30 cow-calf pairs were estrus synchronized at 25 days post-partum. No differences were observed in the number of cows displaying estrus or ovulating between those cows reacting to more calves with higher intensity, and the rest of the herd (P > 0.05). However, significant negative correlations were found between cows reacting to more calves and the presence of follicles (-0.39; P = 0.03), and cows displaying a more intense reaction toward their calf and estrous display (-0.46; P = 0.01). Current results suggest that protective maternal components might affect some reproductive variables.(AU)

Relationship between protective maternal behavior and some reproductive variables in zebu-type cows (Bos indicus)

To determine a possible relationship between protective maternal behavior and some reproductive variables in zebu cows, 30 cow-calf pairs were estrus synchronized at 25 days post-partum. No differences were observed in the number of cows displaying estrus or ovulating between those cows reacting to more calves with higher intensity, and the rest of the herd (P > 0.05). However, significant negative correlations were found between cows reacting to more calves and the presence of follicles (-0.39; P = 0.03), and cows displaying a more intense reaction toward their calf and estrous display (-0.46; P = 0.01). Current results suggest that protective maternal components might affect some reproductive variables.(AU)

Relationship between protective maternal behavior and some reproductive variables in zebu-type cows (Bos indicus)

To determine a possible relationship between protective maternal behavior and some reproductive variables in zebu cows, 30 cow-calf pairs were estrus synchronized at 25 days post-partum. No differences were observed in the number of cows displaying estrus or ovulating between those cows reacting to more calves with higher intensity, and the rest of the herd (P > 0.05). However, significant negative correlations were found between cows reacting to more calves and the presence of follicles (-0.39; P = 0.03), and cows displaying a more intense reaction toward their calf and estrous display (-0.46; P = 0.01). Current results suggest that protective maternal components might affect some reproductive variables.

New approaches to superovulation in goats and sheep / Novos enfoques sobre superovulação em caprinos e ovinos

A superovulação é a principal tecnologia reprodutiva utilizada para a produção de embriões em ovinos e caprinos, mas a imprevisibilidade dos resultados continua sendo sua maior desvantagem. Vários fatores intrínsecos e extrínsecos são responsáveis por respostas superovulatórias variáveis em pequenos ruminantes e, portanto, esta questão é o foco principal de muitos estudos que visam melhorar a produção de embriões in vivo. A raça da doadora de embriões é uma fonte importante de variação nos resultados superovulatórios, e essa variabilidade pode ser observada não apenas entre genótipos prolíficos e não prolíficos. A suplementação com progesterona usada em conjunto com protocolos superovulatórios tem efeitos benéficos no desenvolvimento folicular e na produção de embriões; no entanto, a duração ideal da exposição à progesterona também parece variar entre as raças. Alguns estudos recentes dos tratamentos superovulatórios com hormônio folículo-estimulante (FSH) abordaram o tempo para iniciar um regime, a dose total do hormônio exógeno e o número de administrações. Além disso, embora a atividade ovariana seja fortemente afetada pela estação do ano, as flutuações anuais nas respostas superovulatórias ainda são controversas e mal compreendidas. Por último, vários estudos demonstraram que a eficácia dos tratamentos superovulatórios recorrentes pode diminuir, permanecer constante ou mesmo aumentar. Esta revisão tem como objetivo discutir os principais achados em torno da superovulação em pequenos ruminantes publicados nos últimos cinco anos.

Superovulation is the main reproductive technology used for embryo production in sheep and goats, but the unpredictability of results remains its greatest disadvantage. Several intrinsic and extrinsic factors are responsible for variable superovulatory responses in small ruminants and so this issue is the primary focus of many studies aimed to ameliorate in vivo embryo production. The breed of the embryo donor is an important source of variation in superovulatory outcomes, and such a variability can be seen not only between prolific and non-prolific genotypes. Progesterone priming used in conjunction with superovulatory protocols has beneficial effects on follicular development and embryo production; however, the optimal duration of progesterone exposure also seems to vary between breeds. Some recent studies of the superovulatory treatments using follicle-stimulating hormone (FSH) have addressed the time to start a regimen, total dose of the exogenous hormone, and the number of injections. Moreover, even though the ovarian activity is strongly affected by the season, annual fluctuations in superovulatory responses are still controversial and incompletely understood. Lastly, several studies have shown that the efficacy of recurrent superovulatory treatments can either decline, remain constant or even increase. This review aims to discuss the main findings surrounding superovulation in small ruminants and published in recent five years.

Paeonia lactiflora improves ovarian function and oocyte quality in aged female mice

Although ovarian aging is a key cause of decreased ovarian function and oocyte quality, it remains a problem in infertility treatment. Therefore, this study is aimed to investigate whether Paeonia lactiflora (PL), a herb improves ovarian function and oocyte quality using aged female mice. C57BL/6 female mice aged 8 months were treated orally every day with PL of 26.5 mg/kg (n=7) and 53 mg/kg (n=7) of body weight for 4 weeks using an oral zoned needle. The control group (n=7) was treated with normal saline. Ovaries and serum were collected for the H&E stain and the evaluation of reactive oxygen species (ROS) levels, respectively. In the second experiment, female mice were orally administered with PL (26.5 mg/kg: n=12, 53 mg/kg: n=12, control: n=12) and then superovulated with PMSG and hCG, and mated with male mice. Zygotes were retrieved and cultured for 4 days. Ovaries were provided for examination of expressions of genes associated with angiogenesis (VEGF and visfatin), anti-aging (Sirt1 and Sirt2), and follicular development (c-Kit, BMP-15, and GDF-9). PL significantly increased numbers of surviving follicles (primordial, primary, secondary, and antral), numbers of zygotes retrieved, embryo development rate, and ovarian expression of VEGF, visfatin, c-Kit, BMP-15, and GDF-9 at both doses. However, ovarian expression of Sirt1 and Sirt2 was increased at 53.0 mg/kg of PL. ROS levels were not affected by PL. These results suggest that PL may possess beneficial effects regarding ovarian function and oocyte quality, possibly by activation of ovarian angiogenesis and follicular development.

Paeonia lactiflora improves ovarian function and oocyte quality in aged female mice

Although ovarian aging is a key cause of decreased ovarian function and oocyte quality, it remains a problem in infertility treatment. Therefore, this study is aimed to investigate whether Paeonia lactiflora (PL), a herb improves ovarian function and oocyte quality using aged female mice. C57BL/6 female mice aged 8 months were treated orally every day with PL of 26.5 mg/kg (n=7) and 53 mg/kg (n=7) of body weight for 4 weeks using an oral zoned needle. The control group (n=7) was treated with normal saline. Ovaries and serum were collected for the H&E stain and the evaluation of reactive oxygen species (ROS) levels, respectively. In the second experiment, female mice were orally administered with PL (26.5 mg/kg: n=12, 53 mg/kg: n=12, control: n=12) and then superovulated with PMSG and hCG, and mated with male mice. Zygotes were retrieved and cultured for 4 days. Ovaries were provided for examination of expressions of genes associated with angiogenesis (VEGF and visfatin), anti-aging (Sirt1 and Sirt2), and follicular development (c-Kit, BMP-15, and GDF-9). PL significantly increased numbers of surviving follicles (primordial, primary, secondary, and antral), numbers of zygotes retrieved, embryo development rate, and ovarian expression of VEGF, visfatin, c-Kit, BMP-15, and GDF-9 at both doses. However, ovarian expression of Sirt1 and Sirt2 was increased at 53.0 mg/kg of PL. ROS levels were not affected by PL. These results suggest that PL may possess beneficial effects regarding ovarian function and oocyte quality, possibly by activation of ovarian angiogenesis and follicular development.(AU)

Medium and time conservation affect follicular morphology and superoxide dismutase enzyme activity of bovine preantral follicles during storage at 4ºC / Meio e tempo de conservação afetam a morfologia folicular e atividade da enzima superóxido dismutase de folículos pré-antrais bovinos durante a conservação a 4 ºC

The aim of this study was to evaluate the morphology and superoxide dismutase enzyme (SOD) activity of bovine preantral follicles (PFs) preserved in TCM 199, saline solution or PBS at different conservation periods. Cow ovaries (n=6) were divided into 7 fragments. One small piece of each ovarian fragment was randomly removed to evaluate SOD activity, while the remainder was immediately fixed for morphological evaluation as a control group. The other 6 fragments were randomly distributed in tubes containing TCM 199, saline solution, or PBS and maintained at 4ºC for 6 or 24 h. For histological evaluation, the fragments were fixed in Carnoy and stained with PAS-hematoxylin, following being classified PFs in relation to their follicular morphology in normal or degenerated. Determination of SOD activity was based on the ability to inhibit autoxidation of adrenaline in adrenochrome. Evaluation of follicular morphology showed that follicles preserved in TCM 199 for 6 h did not differ from the control (P > 0.05). In contrast, preservation in saline solution and PBS for 6 or 24 h and TCM 199 for 24 h decreased normal PFs compared to the control (P < 0.05). SOD showed a lower activity in ovarian cortical tissue kept in TCM 199 for 6 h and saline solution for 24 h than in the other groups. Our study shows that incubation using TCM 199 at 4°C for 6 h can be used to efficiently conserve female bovine PFs in situ.(AU)

O objetivo desse estudo foi avaliar a morfologia e atividade da enzima superóxido dismutase (SOD) de folículos pré-antrais bovinos (PFs) preservados em TCM 199, solução salina ou PBS por diferentes períodos de conservação. Ovários de vacas (n=6) foram divididos em 7 fragmentos. Um pequeno pedaço de cada fragmento ovariano foi removido para avaliar a atividade da SOD enquanto que o restante foi imediatamente fixado para avaliação morfológica como grupo controle. Os outros 6 fragmentos foram distribuídos aleatoriamente em tubos contendo TCM 199, solução salina ou PBS e mantidos a 4ºC por 6 ou 24 h. Para avaliação histológica, os fragmentos foram fixados em Carnoy e corados com PAShematoxilina, sendo classificados em seguida os PFs em relação à sua morfologia folicular em normal ou degenerados. A determinação da atividade da SOD foi baseada na capacidade de inibir a autooxidação da adrenalina no adrenocromo. A avaliação da morfologia folicular mostrou que os folículos preservados em TCM199 por 6 h não diferiram do controle (P > 0,05). Em contraste, a preservação em solução salina e PBS por 6 ou 24 h e TCM 199 por 24 h diminuiu os PFs normais em comparação com o controle (P < 0,05). A SOD mostrou uma menor atividade no tecido cortical ovariano mantido em TCM 199 por 6 h e solução salina por 24 h do que nos outros grupos. Nosso estudo mostra que a incubação usando TCM 199 a 4° C por 6 h pode ser usada eficientemente para conservar PFs de fêmeas bovinas in situ.(AU)

Effect of temperature – humidity index on the onset of post- partum ovarian activity and reproductive behavior in Bos indicus cows

The effect of climatic factors on ovarian activity and reproductive behavior (RB) was evaluated in 46 Bos indicus cows kept under grazing conditions. Temperature-humidity index (THI) was used as an indicator of stress and divided in alert, damage and emergency levels. Fat thickness (FAT) was taken during the last trimester of gestation (LTG) to approximately 90d postpartum (PP). At 30d PP animals received a progesterone (P4)-releasing device (CIDR) which was withdrawn 9d later. Ovarian activity was assessed by blood progesterone on days 21, 24, 27, 30, 49, 51, and 54 PP. Animals were divided into three groups, higher, and moderate RB and non-behavior. Sixty percent presented a THI >74 increasing dramatically from June to September up to >78. During LTG, animals lost 27% of their body reserves contrasting to PP where an increase of 2.6% (P=0.002) was observed. The percentages of cyclic and non-cyclic animals were 57 and 43%, respectively (P> 0.05). Seventy-two percent displayed RB and 28% were non-behavior (P<0.05). A negative correlation (r = -0.307; P = 0.038) between THI and RB, and a positive correlation (r = 0.427; P = 0.003) between the onset of ovarian activity and RB were observed. Differences in THI during the LTG (P<0.01) were observed between cyclic and non-cyclic animals. Non-behavior cows in the LTG had a higher THI (P <0.05). High levels of THI have a negative effect on the resumption of ovarian activity and RB in Bos indicus especially if high THI occurs during the last trimester of gestation.

Effect of temperature humidity index on the onset of post- partum ovarian activity and reproductive behavior in Bos indicus cows

The effect of climatic factors on ovarian activity and reproductive behavior (RB) was evaluated in 46 Bos indicus cows kept under grazing conditions. Temperature-humidity index (THI) was used as an indicator of stress and divided in alert, damage and emergency levels. Fat thickness (FAT) was taken during the last trimester of gestation (LTG) to approximately 90d postpartum (PP). At 30d PP animals received a progesterone (P4)-releasing device (CIDR) which was withdrawn 9d later. Ovarian activity was assessed by blood progesterone on days 21, 24, 27, 30, 49, 51, and 54 PP. Animals were divided into three groups, higher, and moderate RB and non-behavior. Sixty percent presented a THI >74 increasing dramatically from June to September up to >78. During LTG, animals lost 27% of their body reserves contrasting to PP where an increase of 2.6% (P=0.002) was observed. The percentages of cyclic and non-cyclic animals were 57 and 43%, respectively (P> 0.05). Seventy-two percent displayed RB and 28% were non-behavior (P<0.05). A negative correlation (r = -0.307; P = 0.038) between THI and RB, and a positive correlation (r = 0.427; P = 0.003) between the onset of ovarian activity and RB were observed. Differences in THI during the LTG (P<0.01) were observed between cyclic and non-cyclic animals. Non-behavior cows in the LTG had a higher THI (P <0.05). High levels of THI have a negative effect on the resumption of ovarian activity and RB in Bos indicus especially if high THI occurs during the last trimester of gestation.(AU)

Subclinical endometritis and postpartum ovarian resumption in respect to TNF-alpha, IL-8 and CRP in Egyptian buffaloes

The study was carried out to find the relation between subclinical endometritis (SCE) and postpartum (pp.) ovarian resumption as well as to evaluate serum and endometrial TNF-α, IL-8 and serum CRP in buffaloes with and without SCE. Thirty-nine pluriparous buffaloes at the 3rd (W3), 5th (W5) and 7th (W7) week pp. were involved in this experiment. The parity of the buffaloes ranged from 4 to 8 with an average 5.8±0.2. Subclinical endometritis was diagnosed by the percentage of polymorphonuclear cells (PMNs) in uterine cytology obtained from endometrial cytobrush at W5 and W7. The cut-off point of PMNs% in buffaloes for SCE was ≥ 6% at W5 or ≥ 4% at W7. According to PMNs%, buffaloes were divided into SCE group (n=27) and non-SCE group (n=12). Ovarian cyclicity was monitored by rectal palpation, ultrasonography and progesterone assay at W3, W5 and W7. Serum and endometrial TNF-α, IL-8 and serum CRP were estimated at W5 and W7. Buffaloes with SCE (55.6%) showed delayed ovarian activity as compared to non-SCE (16.7%) animals (P=0.036). Significant increase in serum cytokines and CRP levels were detected at W5 (P ˂0.05) and W7 (P <0.01) in SCE buffaloes as compared to non-SCE. Endometrial levels of cytokines were significantly (P ˂0.05) elevated in SCE buffaloes. Serum and endometrial cytokines showed significant positive correlation. Furthermore, levels of TNF-α, IL-8 and CRP exhibited significant positive correlation with PMNs%. In conclusion, SCE delayed postpartum ovarian cyclicity in buffaloes. Moreover, TNF-α, IL-8 and CRP assessments could be efficient tools in prediction of SCE in buffaloes.