89 research outputs found
Functional Assessment of Diluent Choice for Semen Cryopreservation from Stallions with High and Low Freezability
Background: fertility rates using horse frozen-thawed semen remain lower than in other livestock species. This fact further suggests that horse semen hold intrinsic sensitivity to cryoinjury that must be investigated. Moreover, there is a substantial influence of genetic factors and diluent choice upon horse cryopreservation outcome. Collectively, these genetic and technical properties of horse semen could be explored to identify factors or conditions that may increase semen viability after freeze-thawing. The aim of this work was to evaluate the effect of diluents Botu-Crio®,Lactose-EDTA®, and INRA-82® on cryopreserved semen from stallions with high (HFA) and low freezability (LFA).Materials, Methods & Results: frozen-thawed semen was evaluated for motility, membrane integrity, and sperm DNA fragmentation using the thermoresistance test (TRT). Comparisons for each parameter were done in a pair-wise fashion between HFA and LFA semen at one-hour intervals during the TRT (0 h - 4 h). Sperm motility in HFA, regardless of the diluent, was larger (P < 0.05) than LFA, both on 0h and 1h. In the 2h evaluation, sperm motility using Botu-Crio® and Lactose-EDTA® was greater (P < 0.05) for HFA. Analysis of sperm membrane integrity was similar between HFA and LFA semen (P > 0.05) at 0 h and 3 h. Sperm DNA fragmentation was lower (P < 0.05) in HFA semen at 0 h and 1 h. Discussion: frozen-thawed semen from stallions of high freezing ability showed greater motility at all analysis, irrespectively of diluent choice, suggesting a strong influence of genetic factors on cryopreservation outcome. Membrane integrity was similar immediately after thawing but did differ later on other TRT time-points, irrespectively of diluent choice. As observed for motility, it was expected that sperm cells of stallions of HFA would show higher membrane integrity than their LFA counterparts. Sperm DNA fragmentation was quite low for both groups, as described in horses. Surprisingly, sperm DNA fragmentation incidence was constant throughout the analysis for both HFA and LFA. It was initially envisioned that increased DNA fragmentation would be found in semen from LFA stallions, since it is caused by multiple origins such as genetic factors. In conclusion, the semen diluent affects horse sperm motility after thawing, particularly from stallions with lower semen freezability
Induction of Ovulation in Mangalarga Marchador Mares by hCG or GnRH
Background: Induction of ovulation is a key procedure for horse assisted reproduction technologies, such as for artificial insemination (AI) and embryo transfer. The application of hCG remains as the primary ovulation-inducing agent for horse assisted reproduction, but alternatives are in demand to avoid its adverse effects, such as loss of ovulation-inducing efficiency over multiple applications by hCC-antibody production. Despite reports on alternative ovulation-inducing agents, pair-wise comparisons of such agents under similar conditions have been limited. Under such scenario, the work was aimed to determine the efficiency of both hCG and Buserelin at inducing ovulation in Mangalarga Marchador mares raised in the Northeast of Brazil under an AI program.Materials, Methods & Results: Mares were initially selected based on their reproductive performance, the absence of clinical-reproductive alterations and adequate body condition score. Mares in diestrus were randomly distributed in three experimental conditions, received 5 mg of Dinoprost and were monitored daily for estrus detection. After estrus detection, ovaries were monitored by ultrasonography, in 12-h intervals, until the follicle reached 35 mm. At this time-point, ovulation was induced with 0.042 mg of Buserelin endovenously, with 3,000 IU hCG by an intramuscular shot, and control mares received 2 mL of saline solution, also by an intramuscular shot. Both hCG and Buserelin displayed similar efficiencies (P > 0.05) for induction of ovulation and that both agents were effective (P 0.05) from those found in the Control. All ovulations occurred within a 72-h period after treatment. It can be observed that in mares treated with hCG or Buserelin, ovulations occurred both in more mares (P 0.05) between hCG and Buserelin groups, and that pregnancy of mares treated with ovulation-inducing factors was similar to the control.Discussion: The majority of ovulations in mares occurred within initial 48-h after treatment for both hCG and GnRH, suggesting a similar potential for horse assisted reproduction. Both hCG and Buserelin are two commonly used agents for induction of ovulation in mares. As described here, the majority of ovulations occurred within initial 48-h after treatment, a fact which can be attributed to hCG and GnRH activity, since it can happen in intervals from 36 to 48-h after treatment. Pregnancy rates did not differ among groups. These results are under the working hypothesis that hCG and Buserelin would display similar efficiencies on pregnancy rates. Despite the understanding of hCG activity on induction of ovulation due to its high specificity toward LH receptors and results from a direct effect on diminishing estradiol concentration, increasing LH, and further inducing ovulation within 48-h after treatment. In contrast, Buserelin has a similar functional property but acts upon LH synthesis and its release. In conclusion, ovulation in mares can be induced with both hCG and Buserelin, and both ovulation-inducing agents do not affect pregnancy rates
Influence of Male to Female Ratio on Hormone Profiles and Reproductive Performance of Anestrus Postpartum Ewes Subjected to the Male Effect
Background: Complete isolation of genders allows intense estrous induction and synchronization once rams are introduced in ewe flocks at the onset of the breeding season (BS). This management practice, defined as the male effect, results from a neuroendocrine process mediated by pheromones. The male effect is a straightforward procedure to induce estrous in noncycling ewes, but conditions for its use have not been fully explored. Thus, this study aimed to evaluate hormone levels and ovarian activity of postpartum ewes in anestrus which are subjected to the male effect under different male to female ratios.Material, Methods & Results: Pospartum females were selected according to body condition score and cyclicity status. Females were kept apart from males during 30 days at a distance of 10 m. Anestrus and ovulation were determined by P4 measures on days 10, 20 and 30 after isolation from males. After P4 concentration diagnosis, anestrus ewe (n = 99) were subjected to male to ewe ratios (MFR) of 1:20 (MFR20), 1:30 (MFR30) and 1:40 (MFR40). Santa Inês rams (n = 3) of proven fertility were used. Three females of each group were randomly subjected to blood collection for LH concentration analysis. Ovarian activity was performed by ultrasonography after estrus manifestation in six ewe of each group. Estrus events were observed twice a day during the BS of 35 days, and estrus were considered synchronized when it occured within the initial five days of the BS. Pregnancy diagnosis was performed by ultrasonography on days 35 and 60 after the last mating. All ewe were in a non-cycling condition before BS onset, based upon P4 analysis. After initiation of the BS, P4 concentrations increased for all groups. Irrespectively of male to female ratio, male effect induced LH pre-ovulatory peaks within the initial 26 to 86 h of the BS. Synchronization of estrus reached 50% for MFR20, 40% for MFR30 and 20% for MFR40 for all ewe. Moreover, overall estrus incidence was 100% (MFR20), 90% (MFR30) and 65% (MFR40) within the initial 15 days of the BS. However, incidence of ewe that had repeated estrus events was lower for MFR20 than for MFR30. Follicular growth and number of ovulations was similar between groups. Conception rates on first service was higher than that of second service for MFR20 and MFR30, although there was no difference between services for MFR40. In contrast, overall conception rates, delivery type and prolificacy were similar between groups.Discussion: P4 increased to cyclicity levels after contact between genders, demonstrating the potential of the male effect to induce estrus in non-cycling ewes. Most ewe ovulated within three days after the male effect, possibly due to elevated basal LH levels. Moreover, the LH preovulatory peak varied within groups, possibly due to greater interactions between genders, which ultimately may have led to earlier ovulation anticipation under lower MFR. Estrus parameters were similar between groups, suggesting low or negligible effects of MFR. Ovulatory follicle size and growth and the number of ovulations were similar between all groups; previous reports have suggested that this may be due to a strong effect of their genetic background. Conception rates were higher at first than second services, demonstrating the potential of male effect. In conclusion, male to female ratio affects the efficiency of the male effect to induce and synchronize estrus in ewes under postpartum anestrus, but it does not affect conception rates and prolificacy
Evaluation of clinical and reproductive parameters in Mangalarga Marchador mares treated with different doses of Cloprostenol or Dinoprost
Avaliou-se a ação de doses reduzidas e convencionais de substâncias luteolíticas sobre parâmetros clínicos e reprodutivos de éguas. As femeas receberam intramuscularmente, 125 ?g (n = 20) e 250 ?g (n = 20) de Cloprostenol e 2.5 mg (n = 20) e 5.0 mg (n = 20) de Dinoprost. A temperatura retal e as frequências cardíaca e respiratória foram aferidas antes e após a administração desses luteolíticos, considerando-se ainda a ocorrência de sudorese, diarreia, cólica e prostração. Monitorou-se o estro e o desenvolvimento folicular até a ovulação, quando realizou-se a inseminção artificial. A gestação foi diagnosticada com 300 e confirmada no 60o dia. Apenas as éguas tratadas com 2,5 e 5,0 mg de Dinoprost apresentaram alteração (P < 0.05) da frequência respiratória e os demais parâmetros não foram alterados (P > 0.05). A sudorese ocorreu em 5% e 10% das éguas tratadas, respectivamente, com 2.5 mg e 5.0 mg de Dinoprost e a diarréia em apenas 5% daquelas que receberam 5.0 mg desse luteolítico. As porcentagens de estro e prenhez das éguas tratadas com 125 ?g de Cloprostenol (45%/35%) e 2.5 mg de Dinoprost (50%/30%) foram menores (P < 0.05) do que os daquelas que receberam 250 ?g de Cloprostenol (85%/70%) e 5 mg de Dinoprost (90%/75%). O estro e a prenhez das éguas Controle foram menores (P < 0.05) do que nas tratadas. Conclui-se que apesar de não promoverem alterações significativas dos parâmetros clínicos, as doses reduzidas não apresentam as mesmas eficiências dos tratamentos com doses convencionais para induzir o estro
DETERMINAÇÃO DO PERÍODO DE MIGRAÇÃO DO TUBÉRCULO GENITAL NA SEXAGEM PRECOCE DE FETOS OVINOS DAS RAÇAS DAMARA, SANTA INÊS E 3/4 DAMARA-SANTA INÊS
Com este estudo, procurou-se determinar, pela ultrasonografia, o período de migração do tubérculo genital (TG) para estabelecimento do momento ideal de sexagem de fetos das raças Damara, Santa Inês e 3/4 Damara-Santa Inês (¾ D-SI). Os exames foram realizados do 30º. ao 60º. dia de prenhez, em intervalos de 24 horas, por via transretal, utilizando-se transdutor linear de dupla freqüência (6,0 e 8,0 MHz). A migração do TG variou de 38 a 51 dias nos fetos da raça Damara, 37 a 46 dias naqueles da raça Santa Inês e de 36 a 45 dias nos fetos ¾ D-SI, perfazendo uma média de 45,0 ± 3,0 dias na raça Damara, de 42,0 ± 2,0 dias na Santa Inês e de 39,2 ± 2,3 dias nos fetos ¾ D-SI. O valor médio da migração do TG é mais precoce (P < 0,05) nos fetos ¾ D-SI do que nos das raças Damara e Santa Inês e mais tardia (P < 0,05) nos da raça Damara do que nos da raça Santa Inês. A acurácia da sexagem fetal nas gestações simples (100%) foi maior (P < 0,05) do que nas gestações duplas (88,5%). Os resultados permitem concluir que a migração do TG é diferente entre os fetos das raças Damara, Santa Inês e ¾ D-SI, que o período ideal de sexagem dessas raças é a partir do 50º dia de gestação e que gestações duplas comprometem a acurácia do exame ultra-sonográfico.
PALAVRAS-CHAVE: Bolsa escrotal, prepúcio, tetas, ultra-sonografia, vulv
Extreme precipitation-streamflow event in the river Araguari basin, Amapá / Brazil
O objetivo da investigação foi analisar vazões extremas ocorridas entre 9 e 14 de abril de 2011 na bacia do Rio Araguari-AP. A metodologia consistiu de três etapas principais: 1) re-análise da precipitação estimada pelo Modelo BRAMS (Brazilian in Development Regional Atmospheric Model System),utilizando como suporte a sinótica do mesmo período; 2) análise de vazão nas seções de monitoramento hidrológico em Porto Platon, Capivara e Serra do Navio (ADCP-Accustic Doppler Profiller Current); 3) análise estatística da série histórica de vazões máximas em Porto Platon utilizando distribuição de Gumbel. Observou-se que o modelo BRAMS capturou parcialmente o padrão do sistema de precipitação quando comparado com a análise sinótica e com os dados da literatura, mas demandando ainda otimização na representação de respostas hidrológicas extremas. Em Porto Platon foi registrada uma vazão recorde de 4036 m3/s, cujo comportamento foi analisado sob a ótica dos mecanismos disponíveis de monitoramento no Estado. Concluiu-se que tais eventos extremos são pouco detectáveis e oferecem riscos consideráveis aos usuários da bacia. A previsão de vazão, baseada na série hidrológica disponível, era de 100 anos de retorno, mas as análises revelaram que este período seria de 360 anos, indicando significativa fragilidade do sistema de previsão de eventos extremos no Estado.The objective of this investigation was to analyse the extreme river flows which have occurred between 9 and 14 April 2011 in the Rio Araguari-AP. The methodology consisted of three main steps: 1) re-analysis of precipitation estimated by the BRAMS (Brazilian Development in Regional Atmospheric Model System) model using the synoptic of the same period as support, 2) analysis of streamflow in sections of hydrological monitoring in Porto Platon, Capivari and Serra do Navio (ADCP-Accustic Profiller Doppler Current); 3) statistic analysis of the time series of maximum river flows in Porto Platon using Gumbel distribution. It was observed that the BRAMS system partially captured the standard precipitation when compared with the synoptic analysis and literature data, but the extreme hydrological responses representation still needs an optimization. In Porto Platon a flow record of 4036 m3 /s was recorded, whose behavior was analyzed from the perspective of the available monitoring mechanisms in the State. It was concluded that such extreme events are poorly detectable and offer considerable risks to users of the basin. The stream flow prediction based on available hydrological series was 100 years recurrence, but the analysis have revealed that this period would be 360 years, indicating significant deficiency of the prediction system of extreme events in the State
Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF
M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe
O micróbio protagonista: notas sobre a divulgação da bacteriologia na Gazeta Médica da Bahia, século XIX
Evaluation of clinical and reproductive parameters in Mangalarga Marchador mares treated with different doses of Cloprostenol or Dinoprost
Avaliou-se a ação de doses reduzidas e convencionais de substâncias luteolíticas sobre parâmetros clínicos e reprodutivos de éguas. As femeas receberam intramuscularmente, 125 ?g (n = 20) e 250 ?g (n = 20) de Cloprostenol e 2.5 mg (n = 20) e 5.0 mg (n = 20) de Dinoprost. A temperatura retal e as frequências cardíaca e respiratória foram aferidas antes e após a administração desses luteolíticos, considerando-se ainda a ocorrência de sudorese, diarreia, cólica e prostração. Monitorou-se o estro e o desenvolvimento folicular até a ovulação, quando realizou-se a inseminção artificial. A gestação foi diagnosticada com 300 e confirmada no 60o dia. Apenas as éguas tratadas com 2,5 e 5,0 mg de Dinoprost apresentaram alteração (P < 0.05) da frequência respiratória e os demais parâmetros não foram alterados (P > 0.05). A sudorese ocorreu em 5% e 10% das éguas tratadas, respectivamente, com 2.5 mg e 5.0 mg de Dinoprost e a diarréia em apenas 5% daquelas que receberam 5.0 mg desse luteolítico. As porcentagens de estro e prenhez das éguas tratadas com 125 ?g de Cloprostenol (45%/35%) e 2.5 mg de Dinoprost (50%/30%) foram menores (P < 0.05) do que os daquelas que receberam 250 ?g de Cloprostenol (85%/70%) e 5 mg de Dinoprost (90%/75%). O estro e a prenhez das éguas Controle foram menores (P < 0.05) do que nas tratadas. Conclui-se que apesar de não promoverem alterações significativas dos parâmetros clínicos, as doses reduzidas não apresentam as mesmas eficiências dos tratamentos com doses convencionais para induzir o estro
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