Background: Semen cryopreservation is one of the most common biotechnologies in the reproduction of animals of agricultural interest, especially bulls. However, cryopreservation can be harmful to sperm cells, with susceptibility to oxidative stress being one of the causes. The addition of antioxidants such as quercetin may inhibit and/or reduce such damage, reducing fertility. Quercetin can increasing sperm motility and interaction capacity between spermatozoa-oocyte, to increase cellular metabolism and reduced DNA fragmentation and oxidation following thawing. Therefore, the objective of this study was to evaluate the protective effect of quercetin on the metabolism of bovine semen following thawing.Material, Methods & Results: Three Brahman bulls in reproduction age and previously considered fit for reproduction were used. The semen samples were collected via the electroejaculation method, and the samples were homogenized to form pooled semen from three ejaculates, which was diluted in Tris-yolk egg-glicerol diluent medium. Quercetin was added to diluent, to final concentrations of 0, 5, 10, 15 and 20 μg.mL-1 in each group. The samples were kept frozen in straws of 500 μL, with concentration of 40,000,000 spermatozoid / mL for 15 days and were thawed in water at 36°C for 30 s. All the tests was performed in five replicates. The cell metabolism status was evaluated by quantification of superoxide radical production with a nitroblue tetrazolium test (NBT) and scanning spectrophotometry. By spermatic evaluation, the following parameters were evaluated via the computerized system of sperm analysis (CASA): total motility (TM, %), progressive motility (PM, %), velocity curved line (VCL, mm/s), velocity straight line (VSL, mm/s), velocity average path (VAP, mm/s), distance curved line (DCL, mm), distance straight line (DSL, mm), distance average path (DAP, mm), amplitude of lateral head displacement (ALH, mm), beat cross frequency (BCF, Hz), wobble (WOB = VAP/VCL), linearity (LIN, VSL:VCL) and straightness (STR, VSL:VAP). And by surface analysis through scanning electron microscopy (SEM). The NBT test demonstrated an increase in cell metabolism of approximately 40% up to the limit of 15 µg.mL-1 quercetin. The parameters of CASA pertaining to velocity (VCL, VSL, VAP) and as a consequence, wobble and linearity increased as a function of the quercetin concentration until 20 µg.mL-1, which was shown to be statistically significant. No significant morphological changes between groups were observed by the SEM technique.Discussion: The reduction of NBT indicates oxidative metabolism, being an indirect measure of the oxygen dependent activity of the cells, therefore the results demonstrate that quercetin supplementation increased the number of cells with high metabolic activity. Regarding the evaluation of CASA, according to the literature, some parameters are reliable estimates of the fertilization capacity of the human spermatozoon, among them, the VCL. In this study, all speeds were increased with Quercetin, including LCV, demonstrating its importance in supplementation in bovine seminal diluent. Scanning electron microscopy evaluates the structural morphology of the cell surface. As with previous results, in this study, all cells lost the acrosome. However, this type of damage was already expected in thawed spermatozoa. In addition, no other significant changes were observed in the morphology of the membrane or other parts of the sperm. In general, the results presented here suggest that the addition of quercetin to the seminal diluent before freezing improve spermatic quality, which manifests itself as faster spermatozoa and may higher fertilization rates.

Background: Brazil is one of the greatest bovine meat exporter in the world. However, the technologies applied at buffalo's reproduction is not specific for this specie, adapted technics were established from the cattle breed. When the animal shows weight gain, gonadal and behavioral physiology fallow this tendency and the reproductive status become good and satisfactory. Thus, the aim of this study was to compare the reproduction characteristics of male buffaloes and its testicular parameters with sexual behavior. Materials, Methods & Results:Seven males Murrah breed with 67.29 ± 11.4 months of age were maintained at confinement for artificial shading. The testicular parameter was performed in restraint trunk and the sexual behavior evaluation was done with an estrus female. The sexual behavior was performed with an estrous female as a dummy. The testicular biometry was measured at the beginning and at the end of the experimental design, with the follow parameters: length, width, depth/thickness, scrotal circumference and the total volume. The data were submitted to the analysis of variance, and the means was compared with the Student-Newman-Keuls test, with significance difference P < 0.05 between the medians. The differences in the parameters were scrotal circumference (23.36 cm vs 24.86 cm), testicular length (8.71 cm vs 9.77 cm), right testicular width (8.57 cm vs 9.53 cm) and testicular volume (1.627.40 cm 3 vs 2.149,68 cm 3 ), respectively. The sexual behavior showed an increase in the Flehmen reflex, mounts (service capacity) and libido (2.00 vs 11.71; 0.57 vs 5.43; regular behavior vs very good behavior, respectively). Discussion: An increase in the testicular circumference was observed at the end of the experimental period with the values between 23.36 cm vs 24.86 cm. However, even with this increase of the testicular parameters it is lower than other male buffaloes with 36 months age. In Brazilian conditions, the testicular circumference variation is between 24.5 cm and 34 cm in animals with 60 months of age. These data shows that there are variations of the testicular parameters due to different systems of buffaloes breeding. When compared to cattle, buffaloes shows lower input of reproductive biotechnology. At the same way, the testicular growth and development depends of the nutrition and management used at the farm. In an inefficient system, buffaloes and bovine breeding could lose weight, testicular mass, and reduce testicular parameters. Besides that, the buffaloes can perform an improvement of a general condition when improvement of nutrition care occurs. The testicular parameters presents high correlation with the corporal and testicular development, which can be correlate to age and weight. Those parameters could help with the reproductive ability of the buffalo. The sexual behavior was increased and observed in the Flehmen reflex, service capacity and libido after the animal's adaptation to the reproductive management. The buffaloes are animals extremely adaptable to different conditions, but...

RESUMO.As éguas são animais reprodutivos estacionais, sendo influenciadas pelas mudanças na relação diária de luminosidade durante o ano, apresentando uma maior dificuldade no controle do ciclo estral, quando comparado aos bovinos. A utilização de indutores de ovulação pode melhorar a eficiência reprodutiva, sincronizando o momento das ovulações e reduzindo o período do estro. Os objetivos deste estudo foi avaliar o uso de indução do estro estimulado por implante de progesterona e o tempo de ovulação em fêmeas equinas utilizando o acetato de deslorelina como indutor de ovulação. Foram utilizadas cinco éguas em idade reprodutiva, que tiveram seu estro induzido por duas vezes cada uma. Em uma das vezes nas mesmas foi administrada com 750mg de acetato de deslorelina. Para indução do estro foi aplicado uma dose de 5mg via IM de prostaglandina F2 no D0 e inserido um dispositivo intra-vaginal que foi removido no D8, sendo concomitante a remoção aplicado uma dose de prostaglandina. Após a remoção dos dispositivos vaginais avaliou-se o crescimento folicular em intervalos de 12/12h até a ovulação. Todos os animais demonstraram comportamento de estro. Éguas tratadas com acetato de deslorelina tiveram o tempo de ovulação em média de 43,2h ±6,57 enquanto o grupo não tratado foi de 84h ±14,70, apresentando diferença significativa. Podendo-se concluir que o uso dispositivo intra-vaginal para bovinos induz a manifestação do estro em éguas; a administração de acetato de deslorelina antecipa o tempo de ovulação contribuindo para um melhor manejo reprodutivo em éguas. Palavras chave: cio, equina, ovário, reprodução Deslorelin acetate to induce ovulation in maresABSTRACT. The mares are seasonal reproductive animals, being influenced by the changes in the daily relation of luminosity during the year, presenting a greater difficulty in the control of the estrous cycle when compared to the cattle. The use of ovulation inducers can improve reproductive efficiency by synchronizing the time of ovulation and reducing the period of estrus. The objectives of this paper were to evaluate the use of progesterone-device for cow estrous induction and ovulation time in mares using deslorelin acetate as an ovulation inducer. Five mares of reproductive age were used, which had their estrus induced twice each. In one of them it was administered with 750 mg of deslorelin acetate. For estrous induction, a 5mg dose was administered via IM of prostaglandin F2alpha at the D0 and an intravaginal device was inserted, which was removed at D8, and a dose of prostaglandin was administered concomitantly. After removal of the vaginal devices follicular growth was evaluated at 12 / 12h intervals until ovulation. All animals showed estrus behavior. Mares treated with deslorelin acetate had a mean ovulation time of 43.2 ± 6.57 while the untreated group was 84.0 ± 14.70, with a significant difference. It

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