Effect of Thawing Procedure and Thermo-Resistance Test on Sperm Motility and Kinematics Patterns in Two Bovine Breeds.

This investigation aimed to analyze the effect that thawing time and temperature in combination with a termo-resistance test had on straws from dairy bulls used for artificial insemination (AI) on semen motility and kinematic variables measured with CASA systems. Eight animals of Holstein and Jersey breeds were used, and nine frozen-thawed semen doses per animal were analyzed for each breed. Three temperatures (35, 37, and 40 °C) and three thawing times (35, 40, and 45 s) were evaluated using a factorial design. Motility and kinematic patterns were analyzed using CASA-mot (Computer-Assisted Semen Analysis of motility) technology at different post-thawing times (0.5, 1, and 2 h). Sperm motility in Jersey bulls was higher (p < 0.05) than in Holstein ones (64.52 ± 1.45% and 53.10 ± 1.40%, respectively). The same effect was seen with progressive motility among the two breeds (Jersey: 45.29 ± 1.00%; Holstein: 36.30 ± 0.98%, p < 0.05). The Jersey breed presented higher values (p < 0.05) of curvilinear velocity (VCL), rectilinear velocity (VSL), average velocity (VAP), linearity on forward progression (LIN), and wobble (WOB). The Holstein breed showed a lower mean value (p < 0.05) of the beat-cross frequency (BCF) compared to the Jersey breed, thus suggesting an effect on VCL and VAP. During the post-thaw period, a gradual increase in VCL was observed at 2 h. VSL and VAP showed a decrease (p < 0.05) as the post-thaw period was prolonged. The study showed differences in sperm quality between Holstein and Jersey breeds, influenced by cryopreservation, thawing, and post-thawing incubation. Thawing at 37 °C for 30 s was considered optimal in relation to sperm motility. In addition, a decrease in sperm quality was observed as post-thawing time increased.

Influence of prenatal corticosteroid therapy on neonatal vitality and utility as a labor-inducing agent in Santa Inês ewes.

Since the 1970s, maternal corticosteroid therapy has been used successfully to induce labor. This allows for better monitoring of parturients and provision of first aid to neonates, improving neonatal viability, as this treatment induces maturation in a variety of fetal tissues, thereby reducing morbidity and mortality. Although the effects of corticosteroids are well known, few studies have investigated the influence of this therapy in Santa Inês sheep. This study aimed to evaluate the efficacy of dexamethasone at two doses (8 and 16 mg) to induce lambing in Santa Inês ewes at 145 days of gestation and assess its effects on neonatal vitality. For this study, 58 ewes raised in an extensive system were investigated. Pregnancy was confirmed after artificial insemination at a set time or after controlled mounting. Ewes were separated into three groups: an untreated control group (G1: 0 mg) and groups treated with two doses of dexamethasone (G2: 8 mg and G3: 16 mg). In total, 79 lambs were born. Their vitality was assessed based on their Apgar score, weight, temperature, and postnatal behavior. SAS v9.1.3 (SAS Institute, Cary, NC) was used to analyze data, considering a 5% significance level for all analyses. The births in the induced groups occurred 48.4 ± 22.1 h after induction, while the ewes that underwent non-induced labor gave birth 131.96 ± 41.9 h after placebo application (p < 0.05), confirming the efficacy of dexamethasone to induce and synchronize labor. The induced and non-induced neonates had similar Apgar scores, temperatures, weights, and postnatal behavioral parameters (p > 0.05). This study showed that inducing labor in Santa Inês ewes at 145 days of gestation with a full (16 mg) or half dose (8 mg) of dexamethasone is an effective technique and does not compromise neonate vitality.

Reproduction of Sheep through Nuclear Transfer of Somatic Cells: A Bibliometric Approach.

Somatic cell nuclear transfer (SCNT) is a reproductive biotechnology with great potential in the reproduction of different species of zootechnical interest, including sheep. This study aimed to carry out a bibliometric analysis of scientific papers published on the application of SCNT in sheep reproduction during the period 1997-2023. The search involved the Science Citation Index Expanded and Social Sciences Citation Index databases of the main collection of the Web of Sciences with different descriptors. A total of 124 scientific papers were analyzed for different bibliometric indicators using the VOSviewer software. Since 2001, the number of SCNT-related papers that have been published concerning sheep reproduction has increased and it has fluctuated in ensuing years. The main authors, research groups, institutions, countries, papers, and journals with the highest number of papers related to the application of SCNT in sheep reproduction were identified, as well as the topics that address the research papers according to the terms: somatic cell, embryo, oocyte, gene expression, SCNT, and sheep.

Administration of Beta-Nerve Growth Factor during the Preovulatory Stage Improves Endocrine and Luteal Function in Dairy Heifers.

The neurotrophin beta-nerve growth factor (NGF), which is present in the semen of different mammals, elicits potent ovulatory and luteotrophic actions in llamas following systemic administration. Here, we determine if purified NGF given intramuscularly (IM) during the preovulatory stage affects the corpus luteum (CL), hormone production, endometrial gene expression, and pregnancy rate of dairy heifers. Holstein-Friesian heifers were estrus-synchronized using estradiol benzoate (EB) plus an intravaginal progesterone (P4) device (DIB). After eight days, the device was removed and cloprostenol was given IM; the next day (day 9), heifers received EB IM plus one of the following: (i) 1 mg of NGF (NGF D9 group), (ii) 1 mg of NGF 32 h after EB (NGF D10 group), or (iii) phosphate buffer saline (control group). To measure pregnancy rates, heifers were treated similarly, then artificially inseminated with sexed semen 48-52 h after DIB removal, then an ultrasound was conducted 30 days after insemination. The females given NGF along with EB (NGF D9) showed significantly higher luteinizing hormone (LH) concentrations, larger CL vascular areas, and higher plasma P4 concentrations than the NGF D10 and control animals. Downregulation of the P4 receptor (PGR), and upregulation of both lipoprotein lipase (LPL) and Solute Carrier Family 6 member 14 (SLC6A14) endometrial genes, were detected in NGF D9 heifers. Furthermore, these heifers had a 10% higher pregnancy rate than the control group. We conclude that the higher P4 output, in response to the early NGF administration, led to the enhanced gene expression of transcripts related to uterine receptivity that may result in enhanced pregnancy rates.

Manipulação de oócitos inclusos em folículos ovarianos pré-antrais e a importância dos antioxidantes ­ revisão de literatura / Manipulation of oocytes included in preantral ovarian follicles and the importance of antioxidants ­ literature review / Manipulación de ovocitos incluidos en folículos ováricos preantrales e importancia de los antioxidantes - revisión de la literatura

A manipulação de oócitos inclusos em folículos ovarianos pré-antrais (MOIFOPA) vem sendo estudada pensando na perspectiva futura de aplicação direta na reprodução humana, principalmente para mulheres que sofrem de doenças ou que precisam passar por tratamentos que interferem na função ovariana. Nesse contexto, o objetivo deste trabalho é revisar aspectos relacionados com a biotécnica de MOIFOPA e a importância dos antioxidantes no cultivo in vitro de folículos pré-antrais. Foi realizada uma pesquisa na base de dados PubMed, buscando artigos sobre a biotécnica, principalmente relacionados com a necessidade do uso de antioxidantes no cultivo. A grande maioria dos estudos sobre a biotécnica utilizam como modelo experimental os folículos ovarianos de diferentes espécies de animais. A MOIFOPA compreende o isolamento e o resgate de folículos ovarianos pré-antrais provenientes de ovários, seguido da conservação através da técnica de resfriamento ou congelação e o cultivo folicular in vitro, a fim de promover o crescimento, a maturação e a fecundação in vitro (FIV) dos oócitos inclusos nesses folículos, maximizando o potencial reprodutivo feminino e diminuindo a atresia folicular que acontece in vivo. Um aspecto que pode interferir no sucesso do cultivo in vitro de folículos ovarianos pré-antrais é a produção em excesso de espécies reativas de oxigênio (EROs). Os ácidos ascórbico e alfa lipóico vem demonstrando resultados interessantes para reduzir os efeitos que as EROs causam sobre os folículos ovarianos pré-antrais cultivados in vitro.

The manipulation of oocytes included in preantral ovarian follicles (MOEPF) has been studied considering the future perspective of direct application in human reproduction, especially for women who suffer from diseases or who need to undergo treatments that interfere with ovarian function. In this context, the objective of this paper is to review aspects related to the biotechnology of MOIFOPA and the importance of antioxidants. A search was carried out in the PubMed database, searching for articles on biotechnology, mainly related to the need to use antioxidants in cultivation. The vast majority of studies on biotechnology use ovarian follicles from different species of animals as an experimental model. MOIFOPA comprises the isolation and rescue of preantral ovarian follicles from ovaries, followed by conservation through the cooling or freezing technique and in vitro follicular cultivation, in order to promote growth, maturation and in vitro fertilization ( IVF) of the oocytes included in these follicles, maximizing the female reproductive potential and decreasing the follicular atresia that occurs in vivo. One aspect that may interfere with the success of in vitro culture of preantral ovarian follicles is the excess production of reactive oxygen species (ROS). Ascorbic and alpha lipoic acids have shown interesting results in reducing the effects that ROS cause on in vitro cultured preantral ovarian follicles.

manipulación de ovocitos incluidos en folículos ováricos preantrales (MOIFOPA) se ha estudiado con la perspectiva futura de su aplicación directa en la reproducción humana, especialmente en mujeres que padecen enfermedades o que necesitan someterse a tratamientos que interfieren en la función ovárica. En este contexto, el objetivo de este trabajo es revisar los aspectos relacionados con la biotécnica de MOIFOPA y la importancia de los antioxidantes en el cultivo in vitro de los folículos pré-antrais. Se realizó una investigación en la base de datos PubMed, buscando artículos sobre la biotecnología, principalmente relacionados con la necesidad del uso de antioxidantes en el cultivo. La mayoría de los estudios sobre biotecnología utilizan como modelo experimental los folículos ováricos de diferentes especies de animales. El MOIFOPA incluye el aislamiento y rescate de los folículos ováricos preantrales de los ovarios, seguido de su conservación mediante la técnica de enfriamiento o congelación y el cultivo folicular in vitro, con el fin de promover el crecimiento, la maduración y la fecundación in vitro (FIV) de los ovocitos incluidos en estos folículos, maximizando el potencial reproductivo femenino y disminuyendo la atresia folicular que se produce in vivo. Un aspecto que puede interferir en el éxito del cultivo in vitro de folículos ováricos preantrales es la producción excesiva de especies reactivas de oxígeno (ROS). El ácido ascórbico y el ácido alfa lipoico han mostrado resultados interesantes para reducir los efectos que causan las ERO en los folículos ováricos preantrales cultivados in vitro.

Manual collapse of blastocoels in not effective in increasing the viability of vitrified equine embryos / Colabamento manual da blastocele não foi efetivo para aumentar a viabilidade de embriões equinos vitrificados

Embryo cryopreservation methods have been used for commercialization and formation of genetic banks. Cryopreservation of equine embryos <300 µm in diameter, collected at days 6-6.5 after ovulation, allows satisfactory pregnancy rates. However, higher embryo collection rates in mares are obtained when uterine flush is performed between days 7 and 8 after ovulation when embryos are >300 µm in diameter, needing blastocoel collapse for satisfactory resistance to cryopreservation by vitrification. To evaluate the viability of simplified blastocoel collapse by embryo puncture with low technology and low-cost equipment, 22 embryos, collected at day 8 post-ovulation (D8), were allocated to the following groups: (1) micropuncture with a 30 G needle, assisted by a mechanical micromanipulator, before vitrification (n=4); (2) manual blade microsection before vitrification (n=6); (3) no manipulation prior to vitrification (n=8); and (4) freshly inovulated embryos (n=4). Despite the high re-expansion rates observed after vitrification, embryos manipulated prior to vitrification (groups MP and MS) did not result in pregnancy 25 days after transfer. On the other hand, embryos from groups NM (non-micromanipulated) and FR (freshly inovulated) resulted in pregnancies at 25 days. Under the conditions of the present study, manual blastocoel collapse was not efficient in increasing cryotolerance to vitrification among large embryos, requiring improvements to obtain pregnancies.(AU)

Métodos de criopreservação de embriões têm sido utilizados com diversos objetivos. Maiores taxas de coleta embrio-nária em éguas com lavagem uterina realizada 7 a 8 dias pós ovulação. A criopreservação de embriões equinos com diâmetro <300 µm (6-6,5 dias após a ovulação) permite a obtenção de taxas de prenhez satisfatórias. Embriões com diâmetro >300 µm (7º dia pós-ovulação) somente são adequadamente criopreservados quando submetidos a colabamento da blastocele. Objetivando avaliar a viabilidade da punção da blastocele com equipamento de baixa sofisticação e custo, 22 embriões coletados no 8º. dia pós-ovulação (D8) foram alocados aos seguintes grupos: (1) micropunção com uma agulha 30 G assistida por micromanipula-dor antes da vitrificação (n=4); (2) microssecção manual por lâmina antes da vitrificação (n=6); (3) sem manipulação anterior à vitrificação (n=8); e (4) transferidos a fresco (n=4). Apesar de altas taxas de reexpansão após a criopreservação, os embriões manipulados previamente a vitrificação não resultaram em prenhez aos 25 dias. Tanto os embriões não micromanipulados, quanto os transferidos a fresco resultaram em prenhezes aos 25 dias. A microssecção manual não se mostrou eficiente como método para aumento da criotolerância de embriões grandes, necessitando um aprimoramento visando a obtenção de prenhezes.(AU)

Heterologous beta-nerve growth factor (ß-NGF) given at the LH surge enhances luteal function in dairy heifers.

Genetic selection for high yield milk production has led to a decline in dairy cattle's reproductive performance over the last 40 years. Low progesterone (P4) plasma content following ovulation is associated with suboptimal fertility in dairy cattle. Several pieces of evidence indicate that the protein beta-nerve growth factor (ß-NGF) that is present in the male seminal plasma exerts potent ovulatory and luteotrophic effects following systemic administration in camelids but also in other species. In this study, we determine whether systemic administration of purified llama ß-NGF given at the induced preovulatory luteinizing hormone (LH) peak improves corpus luteum (CL) function in dairy heifers subjected to an estradiol (E2) / P4 estrus-synchronization protocol. To achieve this, we first determined plasma E2 and LH hormone profiles to establish the timing of the estradiol benzoate (EB)-induced LH peak in estrus-synchronized heifers. Then, we tested whether the administration of ß-NGF given at the end of this peak affects the CL and its function by analyzing diameter, vascular area, and P4 output. Our results show that, with the estrus-synchronization protocol applied, plasma LH concentrations peaked (P < 0.01) 40-h and 16-h after removal of the bovine intravaginal device (DIB; containing 1.0 g of P4) plus cloprostenol injection and subsequent EB administration, respectively; after peaking, plasma LH concentrations remained stable for the next 8-h to then return to basal levels. Heifers synchronized with this protocol and receiving a dose of 1 mg of ß-NGF at the end of the LH peak (ie, 48-h after DIB removal) did not show significant differences in CL diameter, but these exhibited a greater CL vascular area (P = 0.01) than the observed in vehicle-injected heifers. Furthermore, plasma P4 concentration in ß-NGF-treated heifers was higher (P = 0.001) than those quantified in vehicle-injected heifers. These results support the use of ß-NGF in estrus-synchronization protocols to improve the early luteal function in dairy heifers.

Cultivo in vitro de folículos pré-antrais bovinos: revisão, desafios, conquistas e perspectivas futuras / In vitro culture of bovine preantral follicles: review, challenges, achievements and future perspectives

A reprodução animal incide diretamente na eficiência e rentabilidade econômica de um rebanho, sendo considerada um dos fatores de maior importância para os sistemas de produção. Consequentemente, o desenvolvimento e a utilização de biotecnologia são indispensáveis para o aumento da eficiência reprodutiva, do melhoramento genético, da produção de alimentos e geração de riquezas. Nas últimas décadas várias foram as biotécnicas associadas à reprodução animal que apresentaram um grande potencial para a geração de genética, especialmente, ao que se referem aos avanços da reprodução assistida. Estes progressos possibilitaram a utilização de folículos pré-antrais como fonte de oócitos para biotecnologias reprodutivas. Deste modo, a técnica de cultivo in vitro proporciona a retomada do desenvolvimento dos folículos presente na reserva ovariana pela ativação in vitro forçada simulando a ocorrência de distúrbios na foliculogênesse. Até então, apenas a especie murina obteve descendentes vivos através dos folículos primordiais cultivados in vitro. Infelizmente, não há relatos de sucesso em outras espécies, tornando o desenvolvimento de sistemas ideias de cultivo in vitro um desafio. Portanto, o objetivo desta revisão é descrever e discutir os principais avanços da situação atual da pesquisa com folículos pré-antrais inclusos em folículos ovarianos.(AU)

Animal reproduction directly affects the efficiency and economic profitability of a herd, being considered one of the most important factors for production systems. Consequently, the development and use of biotechnology are indispensable for increasing reproductive efficiency, genetic improvement, food production and wealth generation. In the last few decades, biotechnologies associated with animal reproduction have shown great potential for the generation of genetics, especially with regard to advances in assisted reproduction. These advances have enabled the use of pre-antral follicles as a source of oocytes for reproductive biotechnologies. Thus, the in vitro culture technique provides the resumption of the development of follicles present in the ovarian reserve by forced in vitro activation, simulating the occurrence of disturbances in folliculogenesis. Until then, only the murine species obtained living descendants through primordial follicles cultivated in vitro. Unfortunately, there are no reports of success in other species, making the development of ideal in vitro culture systems a challenge.Therefore, the purpose of this review is to describe and discuss the main advances in the current research situation with preantral follicles included in ovarian follicles.(AU)

Cultivo in vitro de folículos pré-antrais bovinos: revisão, desafios, conquistas e perspectivas futuras / In vitro culture of bovine preantral follicles: review, challenges, achievements and future perspectives

A reprodução animal incide diretamente na eficiência e rentabilidade econômica de um rebanho, sendo considerada um dos fatores de maior importância para os sistemas de produção. Consequentemente, o desenvolvimento e a utilização de biotecnologia são indispensáveis para o aumento da eficiência reprodutiva, do melhoramento genético, da produção de alimentos e geração de riquezas. Nas últimas décadas várias foram as biotécnicas associadas à reprodução animal que apresentaram um grande potencial para a geração de genética, especialmente, ao que se referem aos avanços da reprodução assistida. Estes progressos possibilitaram a utilização de folículos pré-antrais como fonte de oócitos para biotecnologias reprodutivas. Deste modo, a técnica de cultivo in vitro proporciona a retomada do desenvolvimento dos folículos presente na reserva ovariana pela ativação in vitro forçada simulando a ocorrência de distúrbios na foliculogênesse. Até então, apenas a especie murina obteve descendentes vivos através dos folículos primordiais cultivados in vitro. Infelizmente, não há relatos de sucesso em outras espécies, tornando o desenvolvimento de sistemas ideias de cultivo in vitro um desafio. Portanto, o objetivo desta revisão é descrever e discutir os principais avanços da situação atual da pesquisa com folículos pré-antrais inclusos em folículos ovarianos.

Animal reproduction directly affects the efficiency and economic profitability of a herd, being considered one of the most important factors for production systems. Consequently, the development and use of biotechnology are indispensable for increasing reproductive efficiency, genetic improvement, food production and wealth generation. In the last few decades, biotechnologies associated with animal reproduction have shown great potential for the generation of genetics, especially with regard to advances in assisted reproduction. These advances have enabled the use of pre-antral follicles as a source of oocytes for reproductive biotechnologies. Thus, the in vitro culture technique provides the resumption of the development of follicles present in the ovarian reserve by forced in vitro activation, simulating the occurrence of disturbances in folliculogenesis. Until then, only the murine species obtained living descendants through primordial follicles cultivated in vitro. Unfortunately, there are no reports of success in other species, making the development of ideal in vitro culture systems a challenge.Therefore, the purpose of this review is to describe and discuss the main advances in the current research situation with preantral follicles included in ovarian follicles.

Criopreservação de sêmen em onças pintadas de cativeiro / Semen cryopreservation in captive jaguars

A onça-pintada é um dos principais animais da fauna brasileira e dentre todos os felinos, a onça-pintada (Panthera onca) somente é menor que o leão (Panthera leo) e o tigre (Panthera tigris), logo sendo classificada como o maior felino de todo o continente americano. Apesar de todo o reconhecimento e importância, a espécie vem sofrendo significativa redução no número de indivíduos. Já há bastante tempo essa espécie vem mantendo seu status de conservação como espécie vulnerável, segundo o Ministério do Meio Ambiente, e próximo de ameaçada, segundo classificação da Lista Vermelha da IUCN. As principais causas que levam à diminuição da população desta espécie estão ligadas à redução no número de suas presas naturais como cervos, queixadas e catetos, e principalmente devido à expansão de áreas urbanas, destruição dos habitats naturais, atropelamentos em rodovias e caça ilegal. Tais fatores capazes de reduzir a população desses animais vem se agravando constantemente devido principalmente as políticas públicas ineficazes para a proteção de espécies ameaçadas. Na contramão desta situação, pesquisadores trabalham visando o desenvolvimento de estratégias com o intuito de proteger a espécie. A estratégia de conservação de maior destaque e de resultado mais rápido a curto prazo são as biotécnicas reprodutivas, uma vez que tais técnicas são capazes de aumentar o número de indivíduos em um curto espaço de tempo. Nas biotécnicas reprodutivas, destaca-se a criopreservação (congelamento) de sêmen, técnica na qual se permite armazenar amostras sob temperaturas extremamente negativas, por um longo período de tempo e também deslocar o material para quaisquer localidades.(AU)

The jaguar is one of the main important animals of the Brazilian fauna and among all felines, the jaguar (Panthera onca) is only smaller than the lion (Panthera leo) and the tiger (Panthera tigris), soon being classified as the largest cat from all over the American continent. Despite all the recognition and importance, the species has undergone a significant reduction in the number of individuals. This species has been maintaining its conservation status as a vulnerable species for a long time, according to the Brazilian Ministry of the Environment, and close to threatened, according to the classification of the IUCN Red List. The main causes that lead to a decrease in the population of this species are related to the reduction in the number of natural prey such as deer, peccary and collared peccary, and mainly due to the expansion of urban areas, destruction of natural habitats, being hit by roads and illegal hunting. Such factors capable of reducing the population of these animals have been constantly worsening due mainly to ineffective public policies for the protection of endangered species. Against this background, researchers are working to develop strategies to protect the species. The conservation strategy of greater prominence and of quicker result in the short term is the reproductive biotechniques, since such techniques are able to increase the number of individuals in a short period of time. In reproductive biotechniques, semen cryopreservation (freezing) stands out, a technique in which samples can be stored under extremely negative temperatures for a long period of time and the material can also be moved to any location.(AU)

Criopreservação de sêmen em onças pintadas de cativeiro / Semen cryopreservation in captive jaguars

A onça-pintada é um dos principais animais da fauna brasileira e dentre todos os felinos, a onça-pintada (Panthera onca) somente é menor que o leão (Panthera leo) e o tigre (Panthera tigris), logo sendo classificada como o maior felino de todo o continente americano. Apesar de todo o reconhecimento e importância, a espécie vem sofrendo significativa redução no número de indivíduos. Já há bastante tempo essa espécie vem mantendo seu status de conservação como espécie vulnerável, segundo o Ministério do Meio Ambiente, e próximo de ameaçada, segundo classificação da Lista Vermelha da IUCN. As principais causas que levam à diminuição da população desta espécie estão ligadas à redução no número de suas presas naturais como cervos, queixadas e catetos, e principalmente devido à expansão de áreas urbanas, destruição dos habitats naturais, atropelamentos em rodovias e caça ilegal. Tais fatores capazes de reduzir a população desses animais vem se agravando constantemente devido principalmente as políticas públicas ineficazes para a proteção de espécies ameaçadas. Na contramão desta situação, pesquisadores trabalham visando o desenvolvimento de estratégias com o intuito de proteger a espécie. A estratégia de conservação de maior destaque e de resultado mais rápido a curto prazo são as biotécnicas reprodutivas, uma vez que tais técnicas são capazes de aumentar o número de indivíduos em um curto espaço de tempo. Nas biotécnicas reprodutivas, destaca-se a criopreservação (congelamento) de sêmen, técnica na qual se permite armazenar amostras sob temperaturas extremamente negativas, por um longo período de tempo e também deslocar o material para quaisquer localidades.

The jaguar is one of the main important animals of the Brazilian fauna and among all felines, the jaguar (Panthera onca) is only smaller than the lion (Panthera leo) and the tiger (Panthera tigris), soon being classified as the largest cat from all over the American continent. Despite all the recognition and importance, the species has undergone a significant reduction in the number of individuals. This species has been maintaining its conservation status as a vulnerable species for a long time, according to the Brazilian Ministry of the Environment, and close to threatened, according to the classification of the IUCN Red List. The main causes that lead to a decrease in the population of this species are related to the reduction in the number of natural prey such as deer, peccary and collared peccary, and mainly due to the expansion of urban areas, destruction of natural habitats, being hit by roads and illegal hunting. Such factors capable of reducing the population of these animals have been constantly worsening due mainly to ineffective public policies for the protection of endangered species. Against this background, researchers are working to develop strategies to protect the species. The conservation strategy of greater prominence and of quicker result in the short term is the reproductive biotechniques, since such techniques are able to increase the number of individuals in a short period of time. In reproductive biotechniques, semen cryopreservation (freezing) stands out, a technique in which samples can be stored under extremely negative temperatures for a long period of time and the material can also be moved to any location.

Programas de inseminação artificial com sêmen congelado de caprinos e ovinos por laparoscopia no Nordeste do Brasil / Programs of artificial insemination with frozen semen of goats and sheep by laparoscopy in Northeast of Brazil

Dentre as biotécnicas aplicadas a reprodução animal, a inseminação artificial (IA) consiste na aplicação do sêmen no aparelho reprodutor da fêmea por meio instrumental. A IA oferece vários benefícios aos criadores, como aceleração do melhoramento genético de animais de interesse econômico, maior controle de doenças sexualmente transmissíveis, facilita a realização do teste de progênie, viabiliza a utilização de sêmen congelado de reprodutores alojados em outras localidades e possibilita que machos com subfertilidade adquirida produzam descendentes. Suas limitações estão relacionadas com carência de mão de obra qualificada, principalmente quando se utiliza a inseminação artificial por laparoscopia, infraestrutura mínima na propriedade para a realização dos procedimentos e aumento dos custos com a aquisição de hormônios. Nesse contexto, a presente revisão de literatura relata os principais pontos que devem ser considerados a fim de superar algumas limitações, bem como, as vantagens da utilização e escolha da melhor técnica.(AU)

Artificial insemination (AI) through laparoscopic techniques has been an important alternative to minimize the difficulties observed in cervical AI in small ruminants. Artificial insemination by laparoscopy facilitates the deposition of the semen directly into the uterine horns of the female, and does not present the cervix as a barrier, especially in sheep that have high sinuosity of the cervical rings. Thus, the use of frozen semen with laparoscopic intrauterine deposition has been important to obtain better fertility indexes in goats and sheep. AI offers several benefits to breeders, such as accelerating the genetic improvement of animals of economic interest, greater control of sexually transmitted diseases, facilitating progeny testing, enabling the use of frozen semen from breeding animals housed in other locations and enabling males with acquired subfertility produce descendants.(AU)

Programas de inseminação artificial com sêmen congelado de caprinos e ovinos por laparoscopia no Nordeste do Brasil / Programs of artificial insemination with frozen semen of goats and sheep by laparoscopy in Northeast of Brazil

Dentre as biotécnicas aplicadas a reprodução animal, a inseminação artificial (IA) consiste na aplicação do sêmen no aparelho reprodutor da fêmea por meio instrumental. A IA oferece vários benefícios aos criadores, como aceleração do melhoramento genético de animais de interesse econômico, maior controle de doenças sexualmente transmissíveis, facilita a realização do teste de progênie, viabiliza a utilização de sêmen congelado de reprodutores alojados em outras localidades e possibilita que machos com subfertilidade adquirida produzam descendentes. Suas limitações estão relacionadas com carência de mão de obra qualificada, principalmente quando se utiliza a inseminação artificial por laparoscopia, infraestrutura mínima na propriedade para a realização dos procedimentos e aumento dos custos com a aquisição de hormônios. Nesse contexto, a presente revisão de literatura relata os principais pontos que devem ser considerados a fim de superar algumas limitações, bem como, as vantagens da utilização e escolha da melhor técnica.

Artificial insemination (AI) through laparoscopic techniques has been an important alternative to minimize the difficulties observed in cervical AI in small ruminants. Artificial insemination by laparoscopy facilitates the deposition of the semen directly into the uterine horns of the female, and does not present the cervix as a barrier, especially in sheep that have high sinuosity of the cervical rings. Thus, the use of frozen semen with laparoscopic intrauterine deposition has been important to obtain better fertility indexes in goats and sheep. AI offers several benefits to breeders, such as accelerating the genetic improvement of animals of economic interest, greater control of sexually transmitted diseases, facilitating progeny testing, enabling the use of frozen semen from breeding animals housed in other locations and enabling males with acquired subfertility produce descendants.

Maturação Oocitária Em Bovinos: Efeito Dos Ácidos Graxos Poli-Insaturados / Oocyte Maturation In Cattle: The Effect Of Polyunsaturated Fatty Acids / Maturación Oocitaria En Bovinos: Efecto De Los Ácidos Graxos Poliinsaturados

Objetivou-se com a presente revisão descrever os eventos que compõe a maturação de oócitos bovinos, pois esta é uma fase crucial da produção in vitro de embriões (PIVE) e o efeito da adição de ácidos graxos poli-insaturados (AGPI) nos meios de cultivo ou na alimentação de bovinos. Dentre os diversos, o ácido linolênico (C18:3; ômega-3) e linoléico (C18:2; ômega-6) são os mais importantes no contexto reprodutivo. A PIVE é uma biotécnica reprodutiva em que todo o processo ocorre mediante etapas sincrônicas, sendo maturação in vitro (MIV), fertilização in vitro (FIV) e cultivo de embriões in vitro (CIV) e para que todo o processo obtenha sucesso é necessária que haja interação e sincronismo entre as etapas cuja maturação oocitária é uma fase essencial e limitante para a PIVE, visto que é através da maturação nuclear e citoplasmática que ocorre o controle sistêmico de todo potencial de desenvolvimento oocitário e, consequentemente garantia do desenvolvimento embrionário.(AU)

The objective of this review was to describe the events that compose the maturation of bovine oocytes, as this is a crucial phase of in vitro embryo production (IVP) and the effect of the addition of polyunsaturated fatty acids (PUFAs) on culture media or in feed for cattle. Among them, linolenic acid (C18: 3; omega-3) and linoleic acid (C18: 2; omega-6) are the most important in the reproductive context. IVP is a reproductive biotechnology in which the whole process takes place through synchronic stages, being in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro embryo culture (IVC) and for the whole process to be successful it is necessary that there is interaction and synchronism between the stages whose oocyte maturation is the essential and limiting phase for IVP since it is through nuclear and cytoplasmic maturation that the systemic control of any oocyte development potential occurs and consequently warranty of embryonic development.(AU)

En el presente trabajo se describen los eventos que componen la maduración de ovocitos bovinos, pues esta es una fase crucial de la producción in vitro de embriones (PIVE) y el efecto de la adición de ácidos grasos poliinsaturados (AGPI) en los medios de cultivo o En la alimentación de bovinos. Entre los diversos, el ácido linolénico (C18: 3, omega-3) y linoleico (C18: 2, omega-6) son los más importantes en el contexto reproductivo. La PIVE es una biotécnica reproductiva en que todo el proceso ocurre mediante etapas sincrónicas, siendo maduración in vitro (MIV), fertilización in vitro (FIV) y cultivo de embriones in vitro (CIV) y para que todo el proceso obtenga éxito es necesario que haya interacción y sincronismo entre las etapas cuya maduración oocitaria es la fase esencial y limitante para la PIVE, ya que es a través de la maduración nuclear y citoplasmática que ocurre el control sistémico de todo potencial de desarrollo oocitario y por consiguiente, garantía del desarrollo embrionario.(AU)

Maturação Oocitária Em Bovinos: Efeito Dos Ácidos Graxos Poli-Insaturados / Oocyte Maturation In Cattle: The Effect Of Polyunsaturated Fatty Acids / Maturación Oocitaria En Bovinos: Efecto De Los Ácidos Graxos Poliinsaturados

Objetivou-se com a presente revisão descrever os eventos que compõe a maturação de oócitos bovinos, pois esta é uma fase crucial da produção in vitro de embriões (PIVE) e o efeito da adição de ácidos graxos poli-insaturados (AGPI) nos meios de cultivo ou na alimentação de bovinos. Dentre os diversos, o ácido linolênico (C18:3; ômega-3) e linoléico (C18:2; ômega-6) são os mais importantes no contexto reprodutivo. A PIVE é uma biotécnica reprodutiva em que todo o processo ocorre mediante etapas sincrônicas, sendo maturação in vitro (MIV), fertilização in vitro (FIV) e cultivo de embriões in vitro (CIV) e para que todo o processo obtenha sucesso é necessária que haja interação e sincronismo entre as etapas cuja maturação oocitária é uma fase essencial e limitante para a PIVE, visto que é através da maturação nuclear e citoplasmática que ocorre o controle sistêmico de todo potencial de desenvolvimento oocitário e, consequentemente garantia do desenvolvimento embrionário.

The objective of this review was to describe the events that compose the maturation of bovine oocytes, as this is a crucial phase of in vitro embryo production (IVP) and the effect of the addition of polyunsaturated fatty acids (PUFAs) on culture media or in feed for cattle. Among them, linolenic acid (C18: 3; omega-3) and linoleic acid (C18: 2; omega-6) are the most important in the reproductive context. IVP is a reproductive biotechnology in which the whole process takes place through synchronic stages, being in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro embryo culture (IVC) and for the whole process to be successful it is necessary that there is interaction and synchronism between the stages whose oocyte maturation is the essential and limiting phase for IVP since it is through nuclear and cytoplasmic maturation that the systemic control of any oocyte development potential occurs and consequently warranty of embryonic development.

En el presente trabajo se describen los eventos que componen la maduración de ovocitos bovinos, pues esta es una fase crucial de la producción in vitro de embriones (PIVE) y el efecto de la adición de ácidos grasos poliinsaturados (AGPI) en los medios de cultivo o En la alimentación de bovinos. Entre los diversos, el ácido linolénico (C18: 3, omega-3) y linoleico (C18: 2, omega-6) son los más importantes en el contexto reproductivo. La PIVE es una biotécnica reproductiva en que todo el proceso ocurre mediante etapas sincrónicas, siendo maduración in vitro (MIV), fertilización in vitro (FIV) y cultivo de embriones in vitro (CIV) y para que todo el proceso obtenga éxito es necesario que haya interacción y sincronismo entre las etapas cuya maduración oocitaria es la fase esencial y limitante para la PIVE, ya que es a través de la maduración nuclear y citoplasmática que ocurre el control sistémico de todo potencial de desarrollo oocitario y por consiguiente, garantía del desarrollo embrionario.

Characterization of the Development of Foals in Natural Mating and Embryo Transfer

Background: Several reproductive biotechnologies are used in horses and embryo transfer (ET) is one of the most frequent in countries like Brazil and the USA. It has been shown that animals originated by new reproductive technology can have compromised growth in extreme conditions, however there are still only a few researches on the influence of embryo transfer over lactating foals under different raising methods. Due to the lack of studies on ET products development and the need to understand the process and its relate with lactating foals growth, the aim of this study was to evaluate the influence of the embryo transfer and natural mate over the newborn foals.Materials, Methods & Results: From a group of 20 mares, 20 Quarter Horse lactating foals were used (10 natural matting + 10 embryo transfer). The mares werent given any concentrate feed during whole gestation and lactation. Foals were kept with the mare, however was used creep feeding to give commercial feed ad libitum. The foals biometric evaluation were made at the day of birth (day 0) and at 30th, 60th, 90th, 120th and 150th day (weaning) for the following parameters: body mass (BM), height at the withers (H), heart girth (HG), cannon bone girth (CBG) and fat mass percentage (FMP). The fat thickness percentage at rump it was determined by ultrasound device. All statistics were considered significant when a P &

Characterization of the Development of Foals in Natural Mating and Embryo Transfer

Background: Several reproductive biotechnologies are used in horses and embryo transfer (ET) is one of the most frequent in countries like Brazil and the USA. It has been shown that animals originated by new reproductive technology can have compromised growth in extreme conditions, however there are still only a few researches on the influence of embryo transfer over lactating foals under different raising methods. Due to the lack of studies on ET products development and the need to understand the process and its relate with lactating foals growth, the aim of this study was to evaluate the influence of the embryo transfer and natural mate over the newborn foals.Materials, Methods & Results: From a group of 20 mares, 20 Quarter Horse lactating foals were used (10 natural matting + 10 embryo transfer). The mares werent given any concentrate feed during whole gestation and lactation. Foals were kept with the mare, however was used creep feeding to give commercial feed ad libitum. The foals biometric evaluation were made at the day of birth (day 0) and at 30th, 60th, 90th, 120th and 150th day (weaning) for the following parameters: body mass (BM), height at the withers (H), heart girth (HG), cannon bone girth (CBG) and fat mass percentage (FMP). The fat thickness percentage at rump it was determined by ultrasound device. All statistics were considered significant when a P &

Characterization of the Development of Foals in Natural Mating and Embryo Transfer

Background: Several reproductive biotechnologies are used in horses and embryo transfer (ET) is one of the most frequent in countries like Brazil and the USA. It has been shown that animals originated by new reproductive technology can have compromised growth in extreme conditions, however there are still only a few researches on the influence of embryo transfer over lactating foals under different raising methods. Due to the lack of studies on ET products development and the need to understand the process and its relate with lactating foals growth, the aim of this study was to evaluate the influence of the embryo transfer and natural mate over the newborn foals.Materials, Methods & Results: From a group of 20 mares, 20 Quarter Horse lactating foals were used (10 natural matting + 10 embryo transfer). The mares werent given any concentrate feed during whole gestation and lactation. Foals were kept with the mare, however was used creep feeding to give commercial feed ad libitum. The foals biometric evaluation were made at the day of birth (day 0) and at 30th, 60th, 90th, 120th and 150th day (weaning) for the following parameters: body mass (BM), height at the withers (H), heart girth (HG), cannon bone girth (CBG) and fat mass percentage (FMP). The fat thickness percentage at rump it was determined by ultrasound device. All statistics were considered significant when a P &

Characterization of the Development of Foals in Natural Mating and Embryo Transfer

Background: Several reproductive biotechnologies are used in horses and embryo transfer (ET) is one of the most frequent in countries like Brazil and the USA. It has been shown that animals originated by new reproductive technology can have compromised growth in extreme conditions, however there are still only a few researches on the influence of embryo transfer over lactating foals under different raising methods. Due to the lack of studies on ET products development and the need to understand the process and its relate with lactating foals growth, the aim of this study was to evaluate the influence of the embryo transfer and natural mate over the newborn foals.Materials, Methods & Results: From a group of 20 mares, 20 Quarter Horse lactating foals were used (10 natural matting + 10 embryo transfer). The mares werent given any concentrate feed during whole gestation and lactation. Foals were kept with the mare, however was used creep feeding to give commercial feed ad libitum. The foals biometric evaluation were made at the day of birth (day 0) and at 30th, 60th, 90th, 120th and 150th day (weaning) for the following parameters: body mass (BM), height at the withers (H), heart girth (HG), cannon bone girth (CBG) and fat mass percentage (FMP). The fat thickness percentage at rump it was determined by ultrasound device. All statistics were considered significant when a P &