Calving date as a potential predictor for the probability of approval in the first breeding soundness evaluation of Nellore bulls.

Beef production systems primarily use natural service (NS) for breeding. However, a significant number of bulls used for NS are subfertile, limiting the profitability of the cow-calf operations. Therefore, producers should select bulls based on breeding soundness evolutions (BSE) to ensure higher pregnancy rates. Several factors can affect the bull ability to pass a BSE. We hypothesize that calving date would be a factor that affects the bull probability of approval at the first BSE. For this purpose, a multivariate logistic regression in a dataset of 14,737 BSEs from young Nellore bulls was used. Correlations between calving date, biometrics, and semen traits were evaluated using Pearson's correlation coefficient. Our results demonstrated that the calving date affected the probability of approval at the first BSE (p < .05). Indeed, the variable that added more information to our model was the calving date, far more than the age group of the bulls according to Akaike's information criterion. Hence, bulls born on day 0 of the calving season have 1.26 more chances to be approved at the first BSE than bulls born 21 days later. This result highlights the importance of getting the dams of future bulls pregnant as soon as possible in the breeding season. In addition, the calving season should be no longer than 47 days to achieve 80% BSE approval in 20-22 months old Nellore bulls. The strongest correlation was with SC, which decreased as the calving date increased. Therefore, the calving date may be used as a predictor of the outcome of the first BSE in young bulls. In that way, the calving date can help seedstock producers to maximize efficiency in making crucial management decisions during the breeding and calving season including nutrition, reproductive, and culling.

Climatic seasons and time of the day influence thermoregulation and testicular hemodynamics in Santa Inês rams raised under humid tropical conditions.

This study evaluated the possible association between the diurnal variations of climatic factors during the rainy (RS) or less rainy (LS) seasons on the testicular hemodynamics and thermoregulatory responses of hair sheep rams raised in a humid tropical climate. Santa Inês rams (n = 6) underwent evaluation of general and testicular physiological parameters (heart and respiratory rates, internal and scrotal temperatures, internal-scrotal temperature gradient, scrotal distention, and color Doppler ultrasound evaluation of the spermatic cords and spectral analyses of testicular arteries) over six consecutive weeks per season at three separate times daily (morning = 8:00 a.m., noon = 12:00 p.m., and afternoon = 5:00 p.m.) during the RS and LS. Climatic air temperature and relative humidity data were recorded, and the temperature and humidity index (THI) was calculated. Higher thermal challenge was observed in LS relative to RS (air temperature = 28.0 vs. 30.9 °C; relative humidity = 84.1 vs. 69.9%; THI = 80.0 vs. 82.5; P < 0.05). In both seasons, respiratory rate and internal temperature were normal, demonstrating the animals' adaptability. In RS, however, a higher scrotal temperature was recorded in relation to LS (35.0 vs. 34.7 °C; P < 0.05), with a gradual increase from morning to afternoon. Lower resistivity (0.40 vs. 0.64; P < 0.05) and pulsatility (0.55 vs. 1.14; P < 0.05) indices, and a higher rate of high-velocity blood flow of testicular arteries (71.1 vs. 60.6%; P < 0.05) were observed in RS compared to LS. The lowest correlations between testicular hemodynamic, physiological variables, and environmental parameters (P < 0.05) were observed in the morning. In conclusion, testicular thermoregulation and testicular hemodynamics were influenced by the climatic seasons and time of the day, being more efficient in the LS season and with less interference from environmental factors in the morning.

Effect of addition of ascorbate, dithiothreitol or a caspase-3 inhibitor to cryopreservation medium on post-thaw survival of bovine embryos produced in vitro.

Experiments were conducted to investigate whether supplementation of cryopreservation medium with ascorbate, dithiothreitol (DTT) or an inhibitor of caspase-3 (z-DEVD-fmk) could improve post-thaw survival of bovine embryos produced in vitro (IVP). For all experiments, embryos were harvested on day 7 after insemination and subjected to controlled-rate freezing in medium containing 1.5 M ethylene glycol and treatments as described below. In experiments 1-3, embryos were cryopreserved in freezing medium with ascorbate (0, 0.1, 0.3 or 0.5 mM), DTT (0, 50, 100 or 200 µM) and z-DEVD-fmk (0, 50, 100 or 200 µM), respectively. Post-thaw survival was assessed at 24, 48 and 72 h. For experiments 4-5, embryos were cryopreserved in freezing medium with or without 0.1 mM ascorbate. At 24 h post-thaw, embryo total cell number, DNA fragmentation and levels of reactive oxygen species (ROS) were evaluated. Embryos subjected to freezing and thawing in medium supplemented with 0.1 mM ascorbate had greater (p < .05) re-expansion rates at 24, 48 and 72 h and hatching rate at 72 h as compared to embryos not treated with ascorbate. Post-thaw cryosurvival was not affected by the addition of either DTT or z-DEVD-fmk to medium used for cryopreservation. Embryos cryopreserved in medium supplemented with 0.1 mM ascorbate had reduced (p < .001) levels of intracellular ROS and fewer (p < .001) cells with DNA fragmentation. In conclusion, post-thaw survival of bovine IVP embryos is enhanced by supplementation of freezing medium with ascorbate.

Influence of Genotype on Endometrial Angiogenesis during Early Pregnancy in Piau and Commercial Line Gilts.

This study aimed to evaluate the endometrial angiogenesis of pregnant commercial line and Piau gilts during early pregnancy. We used 27 gilts, divided into three groups according to the type of mating: Commercial (n = 9), commercial line females mated with commercial line males; Cross-mated (n = 9), Piau females mated with commercial line males; and Piau (n = 9), Piau females mated with Piau males. Each group was divided into three subgroups based on gestational age at the time of slaughter (7, 15, and 30 days of pregnancy). Immediately after slaughter, endometrial samples were obtained for histological evaluation and for analysis of the relative transcript abundance (RTA) of angiogenesis-related genes (HIF1α, FGF9, ANG1, TEK, VEGFA, ANGPT1, and ANGPT2). The number of endometrial glands was similar among groups but decreased with gestational age (p < 0.05). Piau females showed a higher number of blood vessels (p < 0.05) at 7 and 15 days of pregnancy, but no differences were observed among groups at 30 days, suggesting an influence of the male genotype on the pattern of uterine vascularization. There were no differences among groups for RTA of the FGF9, HIF1α, TEK, VEGFA, ANGPT1, and ANGPT2 genes. The HIF1α-gene RTA was higher at 7 and 15 days of pregnancy; for TEK and ANGPT1, the RTA was higher at 15 days of pregnancy; and the RTA of VEGFA and ANGPT2 genes were higher at 30 days of pregnancy. The ANG1 RTA was similar for pregnancies in the commercial and Piau groups but was higher (p < 0.05) at 15 days in the Cross-mated group, suggesting an interaction between genotypes. Overall, the pattern found for the RTA of angiogenesis-related genes was similar among the groups in this study, although some phenotypic differences could be noted, such as the highest number of blood vessels being found during early pregnancy of Piau gilts. The results of the gene RTA when crossed with phenotypic data led to conclusions that are conflicting with those reported in the literature. However, noteworthy is that angiogenesis is a complex process in which the balance between stimulatory and inhibitory factors may be related to time.

Recombinant bovine somatotropin in the synchronization of ovulation in crossbred dairy cows (Bos taurus indicus × Bos taurus taurus).

AIM: The aim of this study was to evaluate the effects of the administration of recombinant bovine somatotropin (rbST) at the moment of implementation of the timed artificial insemination protocol, on follicular dynamics and pregnancy rate in crossbred cows. MATERIALS AND METHODS: A total of 346 cows were used in two experiments with a factorial 2×2 design. The cycling cows (Tcycling) and the anestrous cows (Tanestrous) were considered as factor 1 and the administration of rbST (TrbST) or not (Tcontrol) as factor 2. The experimental protocol: (1) Tcontrol - day 0 (D0), insertion of a progesterone-release intravaginal device (PRID) plus 2 mg of estradiol benzoate (EB); D8, PRID removal, plus 0.150 mg of prostaglandin F2α, and 400 IU of equine chorionic gonadotropin; D9, 1 mg of EB; and with artificial insemination at day 10; (2) TrbST - similar to Tcontrol plus 500 mg of rbST on D0. In experiment I, ultrasound examinations were performed in all treatments. In experiment II, the cows' pregnancy rate was evaluated. Data were analyzed with 5% probability. RESULTS: There was no effect of the protocols on cows cyclicity or follicular growth rate (p>0.05). There was no interaction of the effects, administration of rbST, and the cyclicity of cows on the pregnancy rate. The total pregnancy rate observed was 49.0%. The pregnancy rate in cows receiving rbST was lower for anestrous compared with cycling cows (p<0.05). CONCLUSION: The administration of rbST did not alter the patterns of follicular dynamics nor the ovulation rate. However, cows in anestrous that received rbST had lower pregnancy rates than cycling cows.

Sequential medium with GH and IGF-1 improved in vitro development of bovine preantral follicles enclosed in ovarian tissue.

The growth hormone (GH) and growth insulin-like factor-1 (IGF-1) act directly upon the regulation and growth in the different phases of preantral follicles. Thus, it is necessary to define their sequentiality until the in vitro preovulatory development. Therefore, the study aimed to assess the effects of a sequential medium containing GH and/or IGF-1 in the long-duration in vitro culture of preantral ovarian follicles. Ovarian fragments were cultivated: first half (days 1-7), second half (days 7-14) or during 14 culture days. Treatments were identified as: αMEM+; GH â†’ IGF-1; IGF-1 â†’ GH and GH + IGF-1. The culture was designed in 24-well plates, in an incubator at 37°C and 5% CO2 . The parameters of normality, viability, follicles (primordial/in developing) and follicle diameter were evaluated. In addition, the ultrastructure was confirmed with electron transmission microscopy. The results showed that the culture treated with GH â†’ IGF-1 kept the follicular normality and the viability until the 14th day of culture and increased both in the follicular development until 7th day and in the follicular diameter until 14th day, when compared to the control. The treatments IGF-1 â†’ GH and GH + IGF-1 were not effective in the developing and follicular diameter after 7 days of culture, and also reduced the percentage of viability. It is concluded that the bovine preantral follicles cultured in the sequential medium treated with GH â†’ IGF-1 improved the follicular development until the first half of the culture and kept these parameters with normality, viability and ultrastructure until the second half of the in vitro culture.

Can scrotal circumference-based selection discard bulls with good productive and reproductive potential?

Nonlinear mixed models were used to describe longitudinal scrotal circumference (SC) measurements of Nellore bulls. Models comparisons were based on Akaike's information criterion, Bayesian information criterion, error sum of squares, adjusted R2 and percentage of convergence. Sequentially, the best model was used to compare the SC growth curve in bulls divergently classified according to SC at 18-21 months of age. For this, bulls were classified into five groups: SC < 28cm; 28cm ≤ SC < 30cm, 30cm ≤ SC < 32cm, 32cm ≤ SC < 34cm and SC ≥ 34cm. Michaelis-Menten model showed the best fit according to the mentioned criteria. In this model, ß1 is the asymptotic SC value and ß2 represents the time to half-final growth and may be related to sexual precocity. Parameters of the individual estimated growth curves were used to create a new dataset to evaluate the effect of the classification, farms, and year of birth on ß1 and ß2 parameters. Bulls of the largest SC group presented a larger predicted SC along all analyzed periods; nevertheless, smaller SC group showed predicted SC similar to intermediate SC groups (28cm ≤ SC < 32cm), around 1200 days of age. In this context, bulls classified as improper for reproduction at 18-21 months old can reach a similar condition to those considered as good condition. In terms of classification at 18-21 months, asymptotic SC was similar among groups, farms and years; however, ß2 differed among groups indicating that differences in growth curves are related to sexual precocity. In summary, it seems that selection based on SC at too early ages may lead to discard bulls with suitable reproductive potential.

Peça intermediária de espermatozoides bovinos: funções e anormalidades / Midpiece of bovine spermatozoa: functions and abnormalities

O reprodutor tem grande importância na cadeia produtiva por possuir maior potencial de difusão do seu material genético dentro do rebanho do que as fêmeas que produzem apenas uma cria por ano, em manejo de monta natural. Entretanto, este potencial somente se torna real quando os machos apresentam boa qualidade seminal, resultando em menores taxas de retorno ao estro. No entanto, apesar das características reprodutivas apresentarem baixa herdabilidade, é consensual que algumas patologias espermáticas possam apresentar características hereditárias e neste caso podem permanecer disseminadas nos rebanhos. Entre as anomalias espermáticas identificadas nos ejaculados de bovinos, as patologias de peça intermediária são classificadas como defeitos espermáticos maiores, comprometendo a fertilidade dos reprodutores, porém estas têm recebido pouca atenção. O objetivo deste trabalho de revisão é apresentar os principais estudos sobre a formação da peça intermediária, sua importância e como esta pode sofrer anormalidades, visto que ejaculados com presença destas anomalias apresentam baixa motilidade espermática e fertilidade.(AU)

Bulls are of immense importance in the productive chain because they have a greater potential of diffusion of genetic material within the herd than females that produce only one calf per year in natural mating management. However, this potential is only achieved when males present good seminal quality, resulting in lower rates of return to estrus. Although the reproductive traits have low heritability, it is consensual that some sperm pathologies may present hereditary characteristics and in this case they can remain disseminated in the herds. Among the sperm abnormalities identified in bovine ejaculates, the midpiece pathologies are classified as a major sperm defect, compromising bull fertility, but these pathologies have received little attention. The objective of this review is to present the main studies on the midpiece formation, its importance and how it can undergo abnormalities, since ejaculates with the presence of this pathology present low sperm motility and fertility.(AU)

Peça intermediária de espermatozoides bovinos: funções e anormalidades / Midpiece of bovine spermatozoa: functions and abnormalities

O reprodutor tem grande importância na cadeia produtiva por possuir maior potencial de difusão do seu material genético dentro do rebanho do que as fêmeas que produzem apenas uma cria por ano, em manejo de monta natural. Entretanto, este potencial somente se torna real quando os machos apresentam boa qualidade seminal, resultando em menores taxas de retorno ao estro. No entanto, apesar das características reprodutivas apresentarem baixa herdabilidade, é consensual que algumas patologias espermáticas possam apresentar características hereditárias e neste caso podem permanecer disseminadas nos rebanhos. Entre as anomalias espermáticas identificadas nos ejaculados de bovinos, as patologias de peça intermediária são classificadas como defeitos espermáticos maiores, comprometendo a fertilidade dos reprodutores, porém estas têm recebido pouca atenção. O objetivo deste trabalho de revisão é apresentar os principais estudos sobre a formação da peça intermediária, sua importância e como esta pode sofrer anormalidades, visto que ejaculados com presença destas anomalias apresentam baixa motilidade espermática e fertilidade.

Bulls are of immense importance in the productive chain because they have a greater potential of diffusion of genetic material within the herd than females that produce only one calf per year in natural mating management. However, this potential is only achieved when males present good seminal quality, resulting in lower rates of return to estrus. Although the reproductive traits have low heritability, it is consensual that some sperm pathologies may present hereditary characteristics and in this case they can remain disseminated in the herds. Among the sperm abnormalities identified in bovine ejaculates, the midpiece pathologies are classified as a major sperm defect, compromising bull fertility, but these pathologies have received little attention. The objective of this review is to present the main studies on the midpiece formation, its importance and how it can undergo abnormalities, since ejaculates with the presence of this pathology present low sperm motility and fertility.

Influence of corpus luteum and ovarian volume on the number and quality of bovine oocytes.

In order to evaluate whether ovarian volume, presence and diameter of the corpus luteum (CL) have effects on the number and quality of bovine recovered oocytes, 110 ovaries were obtained from the slaughterhouse. Cumulus oocytes complex were aspirated and evaluated under stereomicroscope. Oocytes were counted and classified according to their quality (Grades I, II, III and IV). Ovarian volume was weakly correlated to the number of good quality oocytes (P < 0.05). Ovaries with CL showed greater numbers of good quality oocytes than ovaries without CL (P < 0.05). Further, presence of CL and its diameter positively influenced the probability of recovering good quality oocytes (P < 0.05). In conclusion, ovarian volume is not a good parameter itself to predict important ovarian characteristics; moreover, analysis of CL, its presence and diameter, may be a good tool to improve efficiency on in vitro embryo production programs.

Características do sêmen caprino descongelado após a adição de Ringer lactato, citrato de sódio e solução Tris / Characteristics of thawed goat semen after addition of Ringer lactate, sodium citrate and Tris solution

Cryopreservation of semen is of great importance for various reproductive biotechnologies such as artificial insemination (IA), In Vitro Embryo Production (PIV) and Intracytoplasmic Sperm Injection (ICSI). The objective of this work was to evaluate the stability and persistence of motility and strength of sperm, as well as changes in the plasma membrane after the addition of Ringer Lactate, sodium citrate 2.92% or TRIS solution in thawed goat semen. Semen was collected from two Alpine Brown goats, and standard procedures for cryopreservation and seminal analysis were performed. After thawing the semen, the extenders Ringer Lactate, sodium citrate 2.92% and TRIS solution were added and Thermoresistance (TTR), Supravital and Morphology Tests were carried out. In TTR, only the group received TRIS solution presented motility and strength for a longer period (90 minutes; P 0,05). No influence of the addition of the solutions was found in the morphological analysis, as well as in the Supravital Test, which showed values ??close to those found for motility (P> 0.05). We concluded that the addition of the solutions does not allow a large persistence of motility and strength of thawed sperm, but TRIS solution could be used for expansion of seminal doses used in vitro reproductive biotechnology.(AU)

A criopreservação do sêmen é de grande importância para diversas biotecnologias da reprodução, como Inseminação Artificial (IA), Produção de Embriões In Vitro (PIV) e Injeção Intracitoplasmática de Espermatozoides (ICSI). Avaliou-se a estabilidade e persistência da motilidade e vigor dos espermatozoides, assim como alterações da membrana plasmática, após a adição de Ringer com Lactato, citrato de sódio 2,92% ou solução TRIS ao sêmen caprino descongelado. O sêmen foi coletado de dois bodes da raça Parda Alpina, realizando-se os procedimentos padrões de análise e criopreservação seminal. Após a descongelação do sêmen, foram adicionados os diluentes Ringer Lactato, citrato de sódio 2,92% ou solução TRIS, realizando-se os Testes de Termorresistência (TTR), Supravital e Morfológico. No TTR, somente o grupo a que foi adicionada a Solução TRIS obteve motilidade e vigor por maior período (90 minutos; P 0,05). Não foi encontrada influência da adição das soluções na análise morfológica, assim como no teste Supravital, o qual apresentou valores próximos aos encontrados para motilidade (P> 0,05). Concluiu-se que a adição das soluções não permite uma grande persistência da motilidade e vigor dos espermatozoides descongelados, porém a solução TRIS poderia ser utilizada para expansão de doses seminais utilizadas em biotecnologias reprodutivas in vitro.(AU)

CARACTERÍSTICAS DO SÊMEN CAPRINO DESCONGELADO APÓS A ADIÇÃO DE RINGER LACTATO, CITRATO DE SÓDIO E SOLUÇÃO TRIS

Cryopreservation of semen is of great importance for various reproductive biotechnologies such as artificial insemination (IA), In Vitro Embryo Production (PIV) and Intracytoplasmic Sperm Injection (ICSI). The objective of this work was to evaluate the stability and persistence of motility and strength of sperm, as well as changes in the plasma membrane after the addition of Ringer Lactate, sodium citrate 2.92% or TRIS solution in thawed goat semen. Semen was collected from two Alpine Brown goats, and standard procedures for cryopreservation and seminal analysis were performed. After thawing the semen, the extenders Ringer Lactate, sodium citrate 2.92% and TRIS solution were added and Thermoresistance (TTR), Supravital and Morphology Tests were carried out. In TTR, only the group received TRIS solution presented motility and strength for a longer period (90 minutes; P 0,05). No influence of the addition of the solutions was found in the morphological analysis, as well as in the Supravital Test, which showed values close to those found for motility (P> 0.05). We concluded that the addition of the solutions does not allow a large persistence of motility and strength of thawed sperm, but TRIS solution could be used for expansion of seminal doses used in vitro reproductive biotechnology.

A criopreservação do sêmen é de grande importância para diversas biotecnologias da reprodução, como Inseminação Artificial (IA), Produção de Embriões In Vitro (PIV) e Injeção Intracitoplasmática de Espermatozoides (ICSI). Avaliou-se a estabilidade e persistência da motilidade e vigor dos espermatozoides, assim como alterações da membrana plasmática, após a adição de Ringer com Lactato, citrato de sódio 2,92% ou solução TRIS ao sêmen caprino descongelado. O sêmen foi coletado de dois bodes da raça Parda Alpina, realizando-se os procedimentos padrões de análise e criopreservação seminal. Após a descongelação do sêmen, foram adicionados os diluentes Ringer Lactato, citrato de sódio 2,92% ou solução TRIS, realizando-se os Testes de Termorresistência (TTR), Supravital e Morfológico. No TTR, somente o grupo a que foi adicionada a Solução TRIS obteve motilidade e vigor por maior período (90 minutos; P 0,05). Não foi encontrada influência da adição das soluções na análise morfológica, assim como no teste Supravital, o qual apresentou valores próximos aos encontrados para motilidade (P> 0,05). Concluiu-se que a adição das soluções não permite uma grande persistência da motilidade e vigor dos espermatozoides descongelados, porém a solução TRIS poderia ser utilizada para expansão de doses seminais utilizadas em biotecnologias reprodutivas in vitro.

Características do sêmen caprino descongelado após a adição de Ringer lactato, citrato de sódio e solução Tris / Characteristics of thawed goat semen after addition of Ringer lactate, sodium citrate and Tris solution

Cryopreservation of semen is of great importance for various reproductive biotechnologies such as artificial insemination (IA), In Vitro Embryo Production (PIV) and Intracytoplasmic Sperm Injection (ICSI). The objective of this work was to evaluate the stability and persistence of motility and strength of sperm, as well as changes in the plasma membrane after the addition of Ringer Lactate, sodium citrate 2.92% or TRIS solution in thawed goat semen. Semen was collected from two Alpine Brown goats, and standard procedures for cryopreservation and seminal analysis were performed. After thawing the semen, the extenders Ringer Lactate, sodium citrate 2.92% and TRIS solution were added and Thermoresistance (TTR), Supravital and Morphology Tests were carried out. In TTR, only the group received TRIS solution presented motility and strength for a longer period (90 minutes; P 0,05). No influence of the addition of the solutions was found in the morphological analysis, as well as in the Supravital Test, which showed values ??close to those found for motility (P> 0.05). We concluded that the addition of the solutions does not allow a large persistence of motility and strength of thawed sperm, but TRIS solution could be used for expansion of seminal doses used in vitro reproductive biotechnology.

A criopreservação do sêmen é de grande importância para diversas biotecnologias da reprodução, como Inseminação Artificial (IA), Produção de Embriões In Vitro (PIV) e Injeção Intracitoplasmática de Espermatozoides (ICSI). Avaliou-se a estabilidade e persistência da motilidade e vigor dos espermatozoides, assim como alterações da membrana plasmática, após a adição de Ringer com Lactato, citrato de sódio 2,92% ou solução TRIS ao sêmen caprino descongelado. O sêmen foi coletado de dois bodes da raça Parda Alpina, realizando-se os procedimentos padrões de análise e criopreservação seminal. Após a descongelação do sêmen, foram adicionados os diluentes Ringer Lactato, citrato de sódio 2,92% ou solução TRIS, realizando-se os Testes de Termorresistência (TTR), Supravital e Morfológico. No TTR, somente o grupo a que foi adicionada a Solução TRIS obteve motilidade e vigor por maior período (90 minutos; P 0,05). Não foi encontrada influência da adição das soluções na análise morfológica, assim como no teste Supravital, o qual apresentou valores próximos aos encontrados para motilidade (P> 0,05). Concluiu-se que a adição das soluções não permite uma grande persistência da motilidade e vigor dos espermatozoides descongelados, porém a solução TRIS poderia ser utilizada para expansão de doses seminais utilizadas em biotecnologias reprodutivas in vitro.

Association of vitamin E with rapid thawing on goat semen.

The aim of this study was to evaluate the effects of vitamin E associated with rapid thawing on cryopreserved goat semen. Two bucks were used and eight ejaculates per animal were collected using artificial vagina. Semen was diluted with the following treatments: BIOXCELL (control), BIOXCELL + Equex (sodium lauryl sulphate) and BIOXCELL + vitamin E 100 µM. Semen was packaged into 0.25 mL straws and cooled at 5°C for 1 hour. Freezing was performed in liquid nitrogen vapor (-155°C) during 15 minutes. Then, the straws were immersed in liquid nitrogen (-196°C). Straws were thawed at 38°C/60 seconds or at 60°C/7 seconds with immediate sperm analysis. Hypoosmotic swelling test was performed adding a 20 µL aliquot of thawed semen to 1 mL of hypoosmotic solution (100 mOsm · Kg(-1)) followed by incubation during 60 minutes in water bath (38°C). Vitamin E did not affect any studied parameters (P > 0.05). Nevertheless, defrosting rate of 60°C/7 seconds improved sperm membrane functional integrity (P < 0.05). Current knowledge about goat semen cryopreservation is not sufficient to ensure high post-thawing recovery rates; thus, this study brings important data about using antioxidants and different thawing rates on cryopreservation process.

Avaliação morfométrica do processo espermatogênico de ratos Wistar adultos expostos ao ácido2, 4diclorofenoxiacético associado ao picloram (TORDON 2,4-D ® 64/240 BR) / Morphometric evaluation of the spermatogenic process of adults wistar rats exposed to the 2, 4diclorophenoxiacetic acid associated to picloram (TORDON 2,4-D® 64/240 BR)

Thirty adult male wistar rats were used in five groups. Two groups received oral treatment withaqueous solution of TORDON 2,4-D®64/240 BR in different concentrations; group O1: 2 ml.L-1(n = 6); groupO2: 4 ml.L-1(n = 6). Two groups received topical treatment in the dorsal cervical area, the followingconcentrations were used, group T1: 16.7 ml.L-1(n = 6), and group T2: 400 ml.L-1(n = 6). A control group wasused without the addition of the herbicide (n = 6). At the end of the experiment, the animals were euthanized; thetestes were collected and fixed for subsequent histological analysis in light microscope. The T1 group showedincrease in albuginea weight (P < 0.05). The animals of the O2 group showed significant reduction (P < 0.05) ofthe height of seminiferous epithelium. The animals of the O1 and T2 groups did not present harmful effects onthe spermatogenic morphometry.(AU)

Trinta ratos Wistar adultos foram usados em cinco grupos. Dois grupos receberam tratamento porvia oral com solução aquosa de 2,4-D Tordon®64/240 BR, em diferentes concentrações, grupo O1: 2 ml.L-1(n =6), grupo de O2: 4 ml.L-1(n = 6). Dois grupos receberam tratamento tópico na região cervical dorsal, foramusadas as seguintes concentrações, grupo T1: 16,7 ml.L-1(n = 6), e um grupo T2: 400 ml.L-1(n = 6). Um grupocontrole foi utilizado sem a adição do herbicida (n = 6). No fim do experimento, os animais foram eutanaziados,os testículos foram removidos e fixados para posterior análise histológica em microscópio de luz. Os animais dogrupo T1 apresentaram aumento no peso da albugínea (P < 0,05). Os animais do grupo de O2 mostraram reduçãosignificativa (P < 0,05) da altura do epitélio seminífero. Os animais dos grupos O1 e T2 não apresentaram efeitosnocivos sobre a morfometria espermatogênica.(AU)

Avaliação morfométrica do processo espermatogênico de ratos Wistar adultos expostos ao ácido2, 4diclorofenoxiacético associado ao picloram (TORDON 2,4-D ® 64/240 BR) / Morphometric evaluation of the spermatogenic process of adults wistar rats exposed to the 2, 4diclorophenoxiacetic acid associated to picloram (TORDON 2,4-D® 64/240 BR)

Thirty adult male wistar rats were used in five groups. Two groups received oral treatment withaqueous solution of TORDON 2,4-D®64/240 BR in different concentrations; group O1: 2 ml.L-1(n = 6); groupO2: 4 ml.L-1(n = 6). Two groups received topical treatment in the dorsal cervical area, the followingconcentrations were used, group T1: 16.7 ml.L-1(n = 6), and group T2: 400 ml.L-1(n = 6). A control group wasused without the addition of the herbicide (n = 6). At the end of the experiment, the animals were euthanized; thetestes were collected and fixed for subsequent histological analysis in light microscope. The T1 group showedincrease in albuginea weight (P < 0.05). The animals of the O2 group showed significant reduction (P < 0.05) ofthe height of seminiferous epithelium. The animals of the O1 and T2 groups did not present harmful effects onthe spermatogenic morphometry.

Trinta ratos Wistar adultos foram usados em cinco grupos. Dois grupos receberam tratamento porvia oral com solução aquosa de 2,4-D Tordon®64/240 BR, em diferentes concentrações, grupo O1: 2 ml.L-1(n =6), grupo de O2: 4 ml.L-1(n = 6). Dois grupos receberam tratamento tópico na região cervical dorsal, foramusadas as seguintes concentrações, grupo T1: 16,7 ml.L-1(n = 6), e um grupo T2: 400 ml.L-1(n = 6). Um grupocontrole foi utilizado sem a adição do herbicida (n = 6). No fim do experimento, os animais foram eutanaziados,os testículos foram removidos e fixados para posterior análise histológica em microscópio de luz. Os animais dogrupo T1 apresentaram aumento no peso da albugínea (P < 0,05). Os animais do grupo de O2 mostraram reduçãosignificativa (P < 0,05) da altura do epitélio seminífero. Os animais dos grupos O1 e T2 não apresentaram efeitosnocivos sobre a morfometria espermatogênica.

Teste de ligação do espermatozoide à membrana perivitelina da gema de ovo após a a adição de Ringer Lactato, Citrato de Sódio 2,92% e solução TRIS no sêmen caprino congelado / Sperm-perivitelline membrane egg binding assay after addition of Ringer Lactate, Sodium Citrate 2.92% and TRIS Solution in thawed goat semen

Com o presente estudo se verificou através do Teste de Ligação dos Espermatozoides à Membrana Perivitelina da Gema de Ovo a capacidade fecundante dessas células após o descongelamento e adição das soluções Ringer com Lactato, Citrato de Sódio 2,92% e TRIS. O sêmen dos animais foi coletado e realizado os procedimentos padrões de análise e criopreservação seminal. Após o descongelamento foi adicionado os diluentes Ringer com Lactato, Citrato de Sódio 2,92 % e Solução TRIS, os quais continham substâncias protetoras aos espermatozoides. Logo após, foram realizados os Testes de Ligação do Espermatozoide à Membrana Perivitelina da Gema de Ovo e Morfológico. Os parâmetros seminais do sêmen fresco ficaram de acordo com preconizado pela legislação vigente (CBRA,1998). A capacidade de ligação dos espermatozoides à membrana perivitelina da gema do ovo foi semelhante entre os tratamentos (P>0,05), mas foi observada correlação positiva entre a motilidade espermática e a capacidade de ligação (P<0,05). A diluição do sêmen criopreservado com soluções isoosmóticas após o descongelamento pode ser útil na manutenção da qualidade espermática e no aumento do volume existente a fim de otimizar a realização de testes e biotecnologias reprodutivas in vitro.(AU)

The present study was verified by testing for binding of sperm to the perivitelline membrane of the egg yolk fertilizing capacity of these cells after thawing and addition of Ringer Lactate, Sodium Citrate 2.92% and TRIS Solution. The semen of animals was collected and performed the standard procedures of analysis and cryopreservation seminal. After thawing was added the solutions Ringer Lactate, Sodium Citrate 2.92% and TRIS, which contained protective substances to sperm and performed the tests in vitro Sperm-Perivitelline Membrane egg Binding and Morphology. The seminal parameters of fresh semen were recommended according to current legislation. The binding capacity of the sperm membrane perivitelline egg yolk was similar between treatments(P>0,05), but there was a positive correlation between sperm motility and binding capacity (P<0,05). Thus, the dilution of semen cryopreserved with solutions isoosmóticas after thawing can be useful in maintaining the quality of sperm and increase existing volume to optimize the testing and reproductive biotechnologies in vitro.(AU)

Teste de ligação do espermatozoide à membrana perivitelina da gema de ovo após a a adição de Ringer Lactato, Citrato de Sódio 2,92% e solução TRIS no sêmen caprino congelado / Sperm-perivitelline membrane egg binding assay after addition of Ringer Lactate, Sodium Citrate 2.92% and TRIS Solution in thawed goat semen

Com o presente estudo se verificou através do Teste de Ligação dos Espermatozoides à Membrana Perivitelina da Gema de Ovo a capacidade fecundante dessas células após o descongelamento e adição das soluções Ringer com Lactato, Citrato de Sódio 2,92% e TRIS. O sêmen dos animais foi coletado e realizado os procedimentos padrões de análise e criopreservação seminal. Após o descongelamento foi adicionado os diluentes Ringer com Lactato, Citrato de Sódio 2,92 % e Solução TRIS, os quais continham substâncias protetoras aos espermatozoides. Logo após, foram realizados os Testes de Ligação do Espermatozoide à Membrana Perivitelina da Gema de Ovo e Morfológico. Os parâmetros seminais do sêmen fresco ficaram de acordo com preconizado pela legislação vigente (CBRA,1998). A capacidade de ligação dos espermatozoides à membrana perivitelina da gema do ovo foi semelhante entre os tratamentos (P>0,05), mas foi observada correlação positiva entre a motilidade espermática e a capacidade de ligação (P<0,05). A diluição do sêmen criopreservado com soluções isoosmóticas após o descongelamento pode ser útil na manutenção da qualidade espermática e no aumento do volume existente a fim de otimizar a realização de testes e biotecnologias reprodutivas in vitro.

The present study was verified by testing for binding of sperm to the perivitelline membrane of the egg yolk fertilizing capacity of these cells after thawing and addition of Ringer Lactate, Sodium Citrate 2.92% and TRIS Solution. The semen of animals was collected and performed the standard procedures of analysis and cryopreservation seminal. After thawing was added the solutions Ringer Lactate, Sodium Citrate 2.92% and TRIS, which contained protective substances to sperm and performed the tests in vitro Sperm-Perivitelline Membrane egg Binding and Morphology. The seminal parameters of fresh semen were recommended according to current legislation. The binding capacity of the sperm membrane perivitelline egg yolk was similar between treatments(P>0,05), but there was a positive correlation between sperm motility and binding capacity (P<0,05). Thus, the dilution of semen cryopreserved with solutions isoosmóticas after thawing can be useful in maintaining the quality of sperm and increase existing volume to optimize the testing and reproductive biotechnologies in vitro.