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As transformações na área de ensino estão em destaque nos últimos anos devido a aplicação de metodologias ativas, práticas pedagógicas e principalmente o uso tecnologias para o aprendizado. No cenário pandêmico, ocasionado pelo coronavírus SARS-CoV-2, a utilização das tecnologias digitais de comunicação e informação para o ensino remoto emergencial se tornaram uma solução para atividades virtuais de aprendizagem. Em vista disso, o presente trabalho propende apresentar a utilização das metodologias ativas no ensino remoto para os estudantes de Medicina Veterinária. O uso dessas estratégias pressupõe a formação de estudantes ativos, que sejam sujeitos protagonistas do processo de aprendizagem. Essas propostas, possibilitam que os indivíduos desenvolvam conhecimentos e habilidades que o capacite a trabalhar em situações e/ou ambientes onde exija-se o trabalho em equipe, a resolução de problemas e interdisciplinaridade. Afinal, essas ferramentas se demonstram capazes de potencializar o ensino-aprendizagem do estudante como protagonista do seu conhecimento.

SummaryThe aim of this study was to evaluate the follicular development, morphological integrity, and oxidative stress of preantral ovarian follicles from Bos taurus indicus females grown in vitro with ascorbic acid. Ovaries (n = 20) from Bos taurus indicus females were collected, fragmented, and were cultured in vitro for 6 or 12 days in minimum essential medium (MEM), or MEM supplemented with 50 or 100 ng/ml ascorbic acid, with an extracellular matrix of agarose gel, in an incubator at 38.5°C; every 2 days, 100% of the culture medium was replaced. The data were analyzed using the chi-squared test and/or Fisher’s exact test. In the event of a significant effect, the proportions were compared using a 2 × 2 proportion test. The oxidative stress analysis data were submitted to analysis of variance followed by the Bonferroni test. Values were considered significant when P ≤ 0.05. The addition of 100 ng/ml of ascorbic acid to the in vitro culture medium of preantral ovarian follicles from bovine females promoted follicular development, was efficient in maintaining morphological integrity, as well as the stability of reactive oxygen species, after 6 days of in vitro culture.

A espécie suína é considerada poliéstrica não estacional e de ciclo regular. A puberdade é marcada pela maturação do trato reprodutivo com o eixo hipotálamo-hipófise gonadal, a partir da secreção do hormônio liberador de gonadotrofinas (GnRH). O ciclo estral é dividido em quatro fases, sendo elas proestro, estro, metaestro e diestro, sendo o estro a fase receptiva ao macho. Anatomicamente, o sistema reprodutor da fêmea é composto de ovários, tubas uterinas, útero, vulva e vagina, cérvix e glândulas mamárias, estas responsáveis pela produção e secreção de leite em casos de gestação. Fisiologicamente, outras etapas estão envolvidas ao que concerne aos aspectos reprodutivos da fêmea, como oogênese, foliculogênese, ovulação, fecundação, gestação, lactação e parto.

Considerando o número de casos de Zika no país e sua influência na saúde da população, este estudo busca analisar histologicamente modelos experimentais de ratas gestantes desafiadas com soro positivo para Zika Vírus, visando entender a influência dessa arbovirose nos principais tecidos maternos e fetais, incluindo tecido renal, do SNC e hepático. Na metodologia, foi utilizado uma amostragem de 10 ratas da linhagem Wistars, que foram desafiadas com o soro positivo no período gestacional, recebendo 3 desafios intraperitoneais de Ac-Zika em intervalos regulares de 1 semana. Após o nascimento, foi avaliado se todos os animais sobreviveram ao teste e se não houve nenhum caso de aborto ou natimorto. Em seguida, foram analisados através de biopsias os tecidos nervosos, renais e hepáticos. A análise histológica foi realizada seguindo os processos de fixação, desidratação, diafanização ou clarificação, inclusão, hidratação e a coloração. Os resultados encontrados evidenciaram que o soro humano positivo para ZIKA não apenas prejudica o desenvolvimento da gestação das ratas, fazendo com que essas tenham um menor número de prole viável, como gera alterações histológicas tanto nas mães como nos fetos viáveis. No SNC foi possível a identificação de diminuição da maturação e crescimento cerebral, somado a um aumento do número de capilares endoteliais, presença de glicose nas células e proliferação microglial. Nos Rins foi possível a visualização de proliferação tubular e infiltrado inflamatório predominantemente linfo-plasmocitario. O fígado não aparenta haver alterações significantes. Permitindo uma verificação mais precisa da influência do vírus em órgãos principais, visto que as alterações clínicas em humanos são muito diversificadas, abrangendo desde casos de fácil resolução a manifestações com sequelas permanentes este estudo foi importante ser realizado. Sendo assim, é possível concluir que o soro humano positivo para ZIKA gera alterações significantes nos tecidos maternos e fetais, evidenciando o agravamento que o quadro pode gerar tanto na mãe como no neonato e o foco da infecção pelos órgãos nobres do corpo, principalmente do SNC.

O Brasil se destaca como o quarto maior produtor de carne suina do mundo e, grande parte do que produzido, e utilizado para abastecimento do mercado interno. Tal fato e reflexo da apreciacao in natura e a versatilidade da carne na producao de diversos subprodutos. Para tanto, o odor sexual de machos inteiros compreende um fator limitante para o crescimento da cadeia suinicola, o qual pode ser resolvido com a utilizacao da imunocastracao. Este trabalho teve como objetivo avaliar a eficiencia da imunocastracao segundo a legislacao vigente, correlacionar os indices de morfometria testicular com as glândulas anexas, e avaliar a qualidade das carcacas de suinos imunocastrados. Foram avaliados 165 suinos machos imunocastrados abatidos em um abatedouro-frigorifico no oeste do Parana. Coletou-se o aparelho reprodutivo dos animais abatidos e em seguida, foram segregados e avaliados quanto ao tamanho da circunferencia escrotal, segundo a legislacao vigente no Parana. Apos a coleta, realizou a dissecacao dos testiculos e das glândulas acessorias para mensuracao da circunferencia, do peso e tamanho. Avaliou-se tambem a colorimetria das carcacas logo apos o abate e 24 horas depois. Dos animais avaliados 89,10% apresentaram circunferencia de testiculos maior do que preconizado na legislacao (> 11 cm). A media geral de circunferencia de testiculos 15,50 ± 2,79 cm, , com peso medio (gramas) de 197,2 ± 87,13 g, para a glândula bulbouretral apresentava media de 9,59 ± 2,14 cm e peso de 35,84 ± 23,91 g, e para a glândula seminal o peso de 48,96 ± 39,5g. Observou-se diferencas significativa (P>0,05) para os parâmetros avaliados, como: peso de testiculos, peso de glândulas seminais, peso e comprimento de glândulas bulbouretrais, sendo estes superiores em suinos com circunferencia de testiculos > 11 cm. Alem disso, houve correlacao crescente para estes dados analisados, ou seja, conforme houve o aumento da circunferencia de testiculos foi possivel observar tambem aumento do tamanho e peso das glândulas acessorias. Na analise de colorimetria da carcaca observou-se que 50% dos animais apresentaram escala 4 nas carcacas quentes e 66,6% apresentaram escala 4 para carcacas frias. Houve diferenca significativa para a colorimetria de carcaca quente, onde os suinos com circunferencia de testiculos > 11 cm apresentaram nota media inferior aos suinos com circunferencia < 11 cm, enquanto para a carcaca fria nao houve diferenca. Pode-se concluir que a maioria dos animais abatidos nao estavam em conformidade com a legislacao vigente, apresentando circunferencia dos testiculos maior do que o preconizado e influenciando no comprimento das glândulas acessorias. Alem disso, os suinos machos imunocastrados nao diferiram estatisticamente na avaliacao da colorimetria da carcaca quente e fria.

SummaryThe aim of this study was to evaluate follicular development, morphological integrity, and antioxidant potential of preantral ovarian follicles from Bos taurus indicus females grown in vitro with alpha-lipoic acid. Ovaries (n = 24) of Bos taurus indicus (n = 12) females were collected during slaughter and fragmented. A randomly obtained fragment from each pair of ovaries was fixed in Bouin (non-cultivated control; D0). These fragments were intended for classical histology (morphology and evaluation of follicular growth), and a fragment from each pair of ovaries was frozen at −80°C (non-cultivated control; D0), and assigned for analysis of oxidative stress [thiobarbituric acid reactive substances (TBARS), nitroblue tetrazolium (NBT), and ferric reducing antioxidant power (FRAP)]. The remaining fragments were cultured in vitro for 6 (D6) or 12 (D12) days, containing only minimum essential medium (MEM) or MEM supplemented with alpha-lipoic acid (50, 100, or 250 ng/ml), on an extracellular matrix of agarose gel, in an oven at 38.5ºC. Every 2 days, 100% of the culture medium was replaced. Supplementation with 100 ng/ml was effective for maintaining follicular integrity after 6 days of culture (primordial: 51.28%; development: 36.88%; P < 0.0001). There was no difference (P > 0.05) between treatments compared with the non-cultivated control treatment (D0), using the NBT and TBARS assays. Therefore, supplementation of the in vitro culture medium of bovine preantral ovarian follicles with a concentration of 100 ng/ml of alpha-lipoic acid at 6 days of culture was effective for maintaining follicular integrity and, after 6 days, maintaining stable levels of reactive oxygen species.

The aim of this study was to evaluate the follicular development, morphological integrity, and oxidative stress of preantral ovarian follicles from Bos taurus indicus females grown in vitro with ascorbic acid. Ovaries (n = 20) from Bos taurus indicus females were collected, fragmented, and were cultured in vitro for 6 or 12 days in minimum essential medium (MEM), or MEM supplemented with 50 or 100 ng/ml ascorbic acid, with an extracellular matrix of agarose gel, in an incubator at 38.5°C; every 2 days, 100% of the culture medium was replaced. The data were analyzed using the chi-squared test and/or Fisher's exact test. In the event of a significant effect, the proportions were compared using a 2 × 2 proportion test. The oxidative stress analysis data were submitted to analysis of variance followed by the Bonferroni test. Values were considered significant when P ≤ 0.05. The addition of 100 ng/ml of ascorbic acid to the in vitro culture medium of preantral ovarian follicles from bovine females promoted follicular development, was efficient in maintaining morphological integrity, as well as the stability of reactive oxygen species, after 6 days of in vitro culture.

The aim of this study was to evaluate follicular development, morphological integrity, and antioxidant potential of preantral ovarian follicles from Bos taurus indicus females grown in vitro with alpha-lipoic acid. Ovaries (n = 24) of Bos taurus indicus (n = 12) females were collected during slaughter and fragmented. A randomly obtained fragment from each pair of ovaries was fixed in Bouin (non-cultivated control; D0). These fragments were intended for classical histology (morphology and evaluation of follicular growth), and a fragment from each pair of ovaries was frozen at -80°C (non-cultivated control; D0), and assigned for analysis of oxidative stress [thiobarbituric acid reactive substances (TBARS), nitroblue tetrazolium (NBT), and ferric reducing antioxidant power (FRAP)]. The remaining fragments were cultured in vitro for 6 (D6) or 12 (D12) days, containing only minimum essential medium (MEM) or MEM supplemented with alpha-lipoic acid (50, 100, or 250 ng/ml), on an extracellular matrix of agarose gel, in an oven at 38.5ºC. Every 2 days, 100% of the culture medium was replaced. Supplementation with 100 ng/ml was effective for maintaining follicular integrity after 6 days of culture (primordial: 51.28%; development: 36.88%; P0.0001). There was no difference (P0.05) between treatments compared with the non-cultivated control treatment (D0), using the NBT and TBARS assays. Therefore, supplementation of the in vitro culture medium of bovine preantral ovarian follicles with a concentration of 100 ng/ml of alpha-lipoic acid at 6 days of culture was effective for maintaining follicular integrity and, after 6 days, maintaining stable levels of reactive oxygen species.

The livestock sector has achieved many technological advances, which have resulted in continued improvements in animal production systems and in the reproductive efficiency of herds. The associated use of reproductive biotechnology and genetic improvements combined with adequate sanitary and nutritional management are essential conditions for sustainable intensified animal production and financial autonomy within farms. Timed artificial insemination (TAI) represents one of the strategies with the greatest impact of expansion in providing genetic improvements and increased reproductive efficiency at a decreased cost. Despite the high proportion of cows receiving TAI, this market still exhibits considerable potential for expansion. After a TAI procedure, approximately 40 to 60% of females become pregnant. This result can vary depending on such factors as the hormonal protocol employed, female category, body condition score, ovarian status, farm management and aspects related to bulls and semen. The fertility and genetic quality of the bull plays an important role in the herd because a single bull can influence the entire production system. Another important strategy is the use of sex-sorted semen associated with TAI, primarily when associated with management practices to improve the pregnancy rate. This paper presents a review of the intensification of TAI, supplying practical information regarding the implementation of TAI commercial programs.

SummaryThis study investigated the in vitro culture of bovine follicles included in ovarian tissue for 2 or 6 days (D2 or D6), with the addition of different concentrations of follicle-stimulating hormone (FSH) (0, 10, 50, 100 or 200 ng/ml). Data were compared for follicular development, morphological integrity and diameter of follicles and oocytes. Ovaries (n = 10) from Nelore cows (n = 5) were divided into fragments (n = 11 per ovary) and were immediately fixed in Bouin’s solution (D0) or were individually cultured for 2 or 6 days in one of the described concentrations of FSH and then processed for histology. Compared with the rates of follicular development at D2 for minimal essential medium (MEM) (75.0%) and 50 ng/ml of FSH (71.1%), the best rates of follicular development at D2 were obtained with 10 (84.7%), 100 (87.5%) and 200 ng/ml of FSH (85.0%; PPPin vitro culture provided appropriate conditions for the development and morphological integrity of preantral follicles in cattle.

Age and antral follicle count (AFC) are related to fertility in cattle, but this information remains limited in mares.To verify the influence of age and AFC on the reproductive characteristics of mares, 15 Quarter Horse donors, with 5-15 antral follicles, ranging from three to 17 years old, healthy and in good nutritional status, were divided into groups with low AFC (≤9 follicles) or high AFC (≥10 follicles) and mares considered young (≤9 years) or old (≥10 years). Mares were submitted to ultrasonography to determine the dominant follicle diameter, follicular growth rate, degree of uterine oedema and embryonic recovery for a minimum of three oestrous cycles.AFC was higher (P=0.001) in young mares compared with old mares. An interaction (P=0.001) between AFC and age was observed with regard to follicular growth rate, being that mares with low AFC and are old showed the lowest follicular growth compared with those of low AFC and young, high AFC and old, and high AFC and young. Younger mares and those with high AFC exhibited higher degree of uterine oedema (P0.05) on the third day of oestrus compared with older mares and with low AFC (3 and 2, respectively). However, in both groups, the degree of oedema reduced by the time of ovulation.Follicular growth rate, degree of uterine oedema and the number of antral follicles are higher in young mares with high AFC. However, the rate of embryonic recovery is not influenced by donors' age or AFC.

Made available in DSpace on 2019-10-06T16:59:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 The objective of this study was to evaluate the effects of forskolin supplementation of the culture medium on the development, lipid content, and transcript levels genes of in vitro-produced bovine embryos. Ovaries (n = 420) from Nelore cows were obtained from the slaughterhouse. On day 5 (D5) of in vitro culture, the embryos in the experimental group were treated with 10 µM of forskolin, and the control group embryos were not treated. The evaluation was performed based on blastocyst and hatching rates on D7 and D10. For the evaluation of lipid deposition, blastocysts (D7; n = 10/group) were stained with the Sudan black B. Additionally, 47 genes were analyzed with RTq-PCR. The embryo lipid content (gray intensity) was similar (P > 0.05) between the forskolin (772 ± 4.8) and control (883 ± 5.2) groups. The mRNA transcript levels of GPX1, HAND1, POU5F1 and HP1 were increased in the control group (P = 0.06). The mRNA transcript level of SREBF1 was equal (P = 0.06) in both treatments, and those of AKR1, IFNT2 (P = 0.06) and SCD (P = 0.08) were increased in forskolin-derived embryos when compared with control embryos. There was no difference (P > 0.05) in the blastocyst production rate between the forskolin (37.9%) and control (39.5%) groups. Interestingly, the blastocyst hatching rate at D10 was higher (P = 0.09) in the forskolin group (62.9%) than in the control group (48.4%). University of Londrina (UEL) Laboratory of Animal Reproduction São Paulo State University (UNESP) Institute of Biosciences Department of Pharmacology São Paulo State University (UNESP) School of Sciences Humanities and Languages Department of Biological Science São Paulo State University (UNESP) Institute of Biosciences Department of Pharmacology São Paulo State University (UNESP) School of Sciences Humanities and Languages Department of Biological Science

The aim of this study was to investigate the efficacy of the tissue fixatives Bouin, Carnoy and 10% Formaldehyde in equine ovarian fragments. Ovaries (n=4) from mares of mixed breeds were obtained at a local slaughterhouse and transported at 20 ºC in a thermo container. Immediately after collection, the ovaries were washed with a modified PBS solution (Cultilab®, Campinas-SP, Brazil) and divided into nine fragments with approximately 5x5x1 mm, removed from the parenchyma of each ovary. The ovarian fragments were then immersed in three different fixatives, Bouin (B) Carnoy (C) or 10% Formaldehyde (F) for 6, 12 or 24 hours. Each fragment was individually immersed in a 20 mL tube containing 20 times the volume of fixative solution. After this period, the fragments were held in 70% ethanol for 24 hours. Each procedure was performed in four replicates. For histological analysis, the specimens were dehydrated in increasing concentrations of alcohol, submitted to diaphanization in xylol and embedded in paraffin. Serial sections of 5 ?m were made with the use of a rotating microtome (Leica® type, Wetzlar, Germany), followed by slide mounting and staining with periodic acid-Schiff (PAS) and hematoxylin. A total of 540 slides with 1,620 sections were evaluated, which contained 465 preantral follicles that were classified as normal or degenerated. Follicles were considered as degenerated when presented at least one of the following aspects: cytoplasm retraction, pyknotic nucleus, cytoplasmic vacuoles, displacement of granulosa cells and/or disruption of the basal membrane. A logistic regression test was used for statistical analysis, and differences were considered significant when P

Folliculogenesis is a process of development and maturation of the ovarian follicles, being essential for the maintenance of fertility. In in vivo conditions, 99.9% of the follicles of an ovary do not ovulate and undergo atresia. In order to minimize this loss and to clarify the existing mechanisms, a technique was developed that allows for the in vitro follicular development. The objective of this study was to evaluate the effects of different epidermal growth factor (EGF) concentrations on the in vitro culturing of equine preantral follicles. Ovaries (n = 10) were collected from a local slaughterhouse of mares in seasonal anestrus, washed with 70% alcohol and PBS, and transported. The inner portion of the ovary was divided into 11 fragments of approximately 3 × 3 × 1 mm. A fragment of each ovary was immediately fixed in Bouin (control group). The remaining 10 fragments were individually cultured for 2 and 6 d. The medium was supplemented with different concentrations of EGF (0, 10, 50, 100, and 200 ng/mL). After cultivation, the fragments were processed and classified according to the developmental stage and morphology. In total, 1065 slides containing 6105 tissue sections were evaluated. Within 2 d of culture, there was a higher proportion of intact follicles at the EGF concentrations of 0 and 100 ng/mL (p > 0.05). After 6 d of culture, only the EGF concentration of 100 ng/mL demonstrated a difference when compared to the other treatments (0, 10, 50 and 200 ng/mL of EGF, p > 0.05). There was follicular development after 2 d at all EGF concentrations. Thus, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in in vitro cultures of ovarian fragments for 2 d. In addition, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in situ cultivation.