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31.
F Minervini R Guastamacchia F Pizzi ME Dell’Aquila VL Barile 《Reproduction in domestic animals》2013,48(2):317-324
Flow cytometry is a useful tool that provides an accurate, objective and rapid evaluation of semen quality. The use of this technique could significantly improve the quality of buffalo semen samples used in artificial insemination. This study was carried out to evaluate, by flow cytometry, frozen–thawed buffalo spermatozoa quality parameters such as sperm viability by SYBR‐14/propidium iodide staining; mitochondrial function by JC‐1 potentiometric probe; sperm chromatin stability (SCSA) by acridine orange; and acrosome reaction (AR) by FITC‐PNA staining. Semen samples from five Italian Mediterranean buffalo bulls were used. Sperm viability was not different between bulls and ranged from 33.4% to 43.6%. A consistent rate (55.1 ± 10.8%) of sperm cells showed high mitochondrial membrane potential (Δψhigh), with no significant differences between subjects. Sperm chromatin structure assay differed significantly between the five buffalo bulls; moreover, data showed high stability within each buffalo. DNA fragmentation indexes (DFI), such as %‐DFI, ‐DFI, SD‐DFI, were 11.2 ± 8.6, 153.3 ± 24.6 and 81.6 ± 21.2, respectively. Regarding AR, the percentage of acrosome‐reacted live (ARL) and acrosome‐reacted dead (ARD) spermatozoa was 0.3 ± 0.2 and 15.3 ± 5.5, respectively. This functional parameter differed significantly between buffalo bulls and showed high stability. Following to Ca2+ ionophore A23187 for 3 h, AR significantly differed between subjects and was characterized by an increase in both ARL (10.8%) and ARD population (22.0%). This study indicates that flow cytometry could be a useful tool for a quick multiparametric evaluation of sperm quality in buffalo. In particular, SCSA and AR resulted in sperm functional parameters sensitive enough for the diagnosis of frozen‐thawed semen fertilizing potential. 相似文献
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OBJECTIVE: To investigate the use of a specific antibody index (AI) that relates Sarcocystis neurona-specific IgG quotient (Q(SN)) to total IgG quotient (Q(IgG)) for the detection of the anti-S neurona antibody fraction of CNS origin in CSF samples obtained from horses after intragastric administration of S neurona sporocysts. ANIMALS: 18 adult horses. PROCEDURES: 14 horses underwent intragastric inoculation (day 0) with S neurona sporocysts, and 4 horses remained unchallenged; blood and CSF samples were collected on days - 1 and 84. For purposes of another study, some challenged horses received intermittent administration of ponazuril (20 mg/kg, PO). Sarcocystis neurona-specific IgG concentrations in CSF (SN(CSF)) and plasma (SN(plasma)) were measured via a direct ELISA involving merozoite lysate antigen and reported as ELISA units (EUs; arbitrary units based on a nominal titer for undiluted immune plasma of 100,000 EUs/mL). Total IgG concentrations in CSF (IgG(CSF)) and plasma (IgG(plasma)) were quantified via a sandwich ELISA and a radial immunodiffusion assay, respectively; Q(SN), Q(IgG), and AI were calculated. RESULTS: Following sporocyst challenge, mean +/- SEM SN(CSF) and SN(plasma) increased significantly (from 8.8 +/- 1.0 EUs/mL to 270.0 +/- 112.7 EUs/mL and from 1,737 +/- 245 EUs/mL to 43,169 +/- 13,770 EUs/mL, respectively). Challenge did not affect total IgG concentration, Q(SN), Q(IgG), or AI. CONCLUSIONS AND CLINICAL RELEVANCE: S neurona-specific IgG detected in CSF samples from sporocyst-challenged horses appeared to be extraneural in origin; thus, this experimental challenge may not reliably result in CNS infection. Calculation of a specific AI may have application to the diagnosis of S neurona-associated myeloencephalitis in horses. 相似文献
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Effect of short‐term exposure of cumulus–oocyte complex to 3‐morpholinosydnonimine on in vitro embryo development and gene expression in cattle
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P Loren C Cheuquemán E Sánchez J Risopatrón ME Arias R Felmer R Sánchez 《Reproduction in domestic animals》2016,51(6):1010-1019
Short‐term exposure of gametes to different types of stress might induce stress tolerance in mammalian embryos. The aim of this study was to evaluate the effect of short‐term exposure of bovine mature cumulus–oocyte complex (COC) to 3‐morpholinosydnonimine (SIN‐1) on subsequent in vitro embryo development, embryo quality and relative gene expression. Matured COCs were incubated with SIN‐1 (0, 0.1, 1, 10 and 100 μM SIN‐1) for 1 hr before in vitro fertilization and zygotes were cultured until Day 7. The cleavage rate at 72 hr did not show any differences among groups. However, the blastocyst rate on Day 7 decreased with all treatments evaluated, with the embryos generated with 10 μM SIN‐1 showing the lowest embryo production rate. Embryo quality analysis did not show any differences in total cell number (TCN) or inner cell mass (ICM) among groups. Relative gene expression analysis showed a downregulation of eNOS expression and an upregulation of nNOS expression in all treatments evaluated compared to the control group. Also, a downregulation was observed in some treatments: SOD2 at 0.1 μM; SOD1 at 0.1 and 100 μM; PRDX5 at 0.1, 10 and 100 μM; and NANOG at 10 and 100 μM; and an upregulation of CDX2 expression was observed at 100 μM. The other genes (OCT4, HIF1A, HSPA1A, BCL2A and iNOS) did not show any differences in the relative gene expression. These results suggest that the short‐term exposure of mature bovine COCs to SIN‐1 does not induce stress tolerance and has no beneficial effect on bovine in vitro embryo production. 相似文献
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In Accelerated Recurrent Selection (ARS) schemes, selection is based on the predicted performance of progeny families, estimated as the average of the parental families. These schemes can halve cycle time compared to simple recurrent selection methods. They also have a lower requirement for evaluation of families in yield trials, although they do require more seed production. ARS therefore provides options in cycle time, effective population size, response to selection and cost which have not been available before. Example schemes are compared by computer simulation with truncation selection and with optimal family selection, where contributions of families to the next generation are optimised to give the maximum response to selection at a specified effective population size. In many circumstances, ARS schemes compare favourably. Difficulties in combining estimates of selection intensity and of effective population size when comparing the merits of different breeding schemes are discussed. It is suggested that unless one is interested in response to selection over periods greater than 50 years, the weight given to effective population size in ranking different schemes should be small. 相似文献
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MARTIN GUILLOT MARC-ANDRÉ D'ANJOU KATE ALEXANDER CHRISTIAN BÉDARD MICHEL DESNOYERS GUY BEAUREGARD JÉRÔME R. E. DEL CASTILLO 《Veterinary radiology & ultrasound》2009,50(5):513-518
While abdominal ultrasound and ultrasound-guided fine-needle aspiration cytology are often combined to help determine the type of liver disease in dogs, little is known about the relationship that may exist between the results of these tests. We hypothesized that specific sonographic findings, or combinations of findings, may predict results of liver ultrasound-guided fine-needle aspiration cytology. Hepatic and extrahepatic sonographic findings were recorded prospectively using a standardized form in 70 dogs with clinically suspected liver disease and in which liver ultrasound-guided fine-needle aspiration cytology was performed. The predictive value of sonographic findings in regard to the category of cytology results was assessed with stepwise logistic regression analysis. Sonographic detection of a hepatic mass (≥3 cm; risk ratio [RR] 3.83, 95% Wald confidence intervals [95% CI] 2.42–3.93, P =0.0036), ascites (RR 3.82, 95% CI 1.94–4.28, P =0.0044), abnormal hepatic lymph node(s) (RR 3.01, 95% CI 1.22–4.88, P =0.0262), and abnormal spleen (RR 3.26, 95% CI 1.20–3.85, P =0.0274) were the most predictive of liver neoplasia on cytology. Conversely, sonographic detection of hepatic nodules (<3 cm; RR 1.97, 95% CI 0.95–2.96, P =0.0666) was most predictive of vacuolar hepatopathy on cytology. In dogs with suspected liver disease, several sonographic findings, alone or combined, are thus predictive of liver ultrasound-guided fine-needle aspiration cytology results. In the light of the fact that ultrasound-guided fine-needle aspiration cytology of the liver has limitations, these predictabilities could influence the selection of diagnostic tests to reach a reliable diagnosis. 相似文献
37.
成都平原不同耕作模式的农田效应研究—— II.土壤综合质量评价 总被引:1,自引:0,他引:1
【目的】研究成都平原不同耕作模式对土壤质量性状的影响,探索建立适合当地生产条件的土壤质量评价体系,筛选出适宜该地的耕作模式,为提高当地土壤生产力水平、改善土壤质量提供借鉴。【方法】通过长期定位试验获取不同耕作模式对土壤性状及作物生产指标的影响效应,采用主成分分析的方法筛选评价指标,运用因子分析法对土壤质量进行综合评价。【结果】筛选出的评价土壤综合质量的指标在不同土壤层次存在明显差别:0—10 cm土层的主要影响因子为毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度、土壤有机质;10—20 cm土层的主要影响因子为总孔隙度、非毛管孔隙度、饱和渗水速率、土壤吸湿水、土壤紧实度;0—20 cm土层的主要影响因子为非毛管孔隙度、土壤比重、土壤饱和渗水速率、土壤紧实度。其中,不同土层的共同影响因子——土壤饱和渗水速率和土壤紧实度是目前当地土壤质量的限制因子。土壤质量综合评价结果表明0—10 cm土层以麦稻双免耕作模式最好,10—20 cm土层麦免+稻旋最好,0—20 cm土层麦免+稻旋最好。【结论】在本研究的试验条件和当地实际情况下,对成都平原土壤质量具有良好效益的耕作模式为麦免+稻旋模式。 相似文献
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Summary The susceptibility to tuber blight (Phytophthora infestans) of seedling progenies from ten crosses involving resistant and susceptible parents was assessed by inoculating tubers grown
in the glasshouse and in the field. The mean level of tuber blight in each progeny corresponded with the resistance category
of the cross, and the rank order of increasing susceptibility was almost identical in both tests. It is suggested that two
samples of ten glasshouse-grown seedlings, each seedling providing two tubers harvested as the plants begin flowering, is
an adequate sample size on which to predict the tuber blight susceptibility of a progeny.
Zusammenfassung Die Anf?lligkeit gegen Knollenbraunf?ule von 10 Nachkommen, einmal von Knollen im Gew?chshaus angezogener S?mlinge (1984), zum anderen von im Feld gewachsener Pflanzen (1985), wurde verglichen. Vier Nachkommen von resistenten Eltern, drei von anf?lligen Eltern und drei aus ‘resistent x anf?llig’-Kreuzungen (Tabelle 1) wurden in zwei Blocks von 40 Pflanzen 9 Wochen lang in 10 cm-T?pfen angezogen. Acht Proben von 10 Pflanzen wurden von jedem Nachkommen entnommen (und zwei Knollen von jedem Topff zu Beginn der Blüte Anfang September), durch Tauchen in eine Zoosporen-Suspension vonPhytophthora infestans inokuliert, und 8 Tage danach die Anzahl der infizierten Knollen festgestellt. Der mittlere Grad von Braunf?ule bei jedem Nachkommen entsprach der Resistenzgruppe der Kreuzung (Tabellen 2 und 3). Im Gew?chshaus angezogene Knollen der gleichen Nachkommen wurden im Feld in zwei Wiederholungen (Blocks) mit 16 bzw. 23 S?mlingen je Nachkommen ausgepflanzt. Die beiden Blocks wurden mit Schwester-Knollen bepflanzt, so dass jeder S?mling in beiden Blocks vorhanden war. Die Knollen wurden nach 16 Wochen geerntet, danach inokuliert und wie zuvor geschildert ausgewertet. Die Rangfolge mit ansteigender Anf?lligkeit war in beiden Tests fast identisch (Tabelle 2). Daraus wird geschlossen, dass zwei Partien von 10 S?mlingen mit je 2 Knollen eine angemessene Probengr?sse zur Vorhersage der Knollenf?ule-Anf?lligkeit eines Nachkommens darstellen (Tabelle 4). Der Test ist schnell und einfach in der Handhabung und erm?glicht in Verbindung mit einer Prüfung der Krautf?uleanf?lligkeit die M?glichkeit einer Auslese sowohl auf Krautf?ule als auch auf Knollen-Braunf?ule im gleichen Jahr.
Résumé La sensibilité de 10 lignées au mildiou du tubercule est évaluée à partir de tubercules issues de plantules cultivées en serre (1984) et en plein champ (1985). Quatre lignées de parents résistants, 3 de parents sensibles et 3 de croisements résistant x sensible (tableau 1) sont cultivés dans deux blocs de 40 plantes mises en pots de 10 cm pendant 9 semaines. Huit échantillons de dix plantes sont prélevés dans chaque lignée et deux tubercules sont retirés de chaque pot au premier stade de la floraison début septembre, puis inoculés par trempage dans une suspension de zoospores deP. infestans; le nombre de tubercules contaminés est enregistré après 8 jours. Le niveau moyen de contamination dans chaque lignée correspond à la catégorie de résistance du croisement (tableaux 2 et 3). Les tubercules issus de la serre et appartenant aux mêmes lignées sont plantés en plein champ dans deux blocs, chacun comprenant deux échantillons de 16 à 23 plantules par lignée. Les deux blocs sont plantés avec des tubercules d'un même pied, de sorte qu'il y a deux répétitions pour chaque plantule. Les tubercules sont récoltés après 16 semaines puis inoculés et notés comme précédemment. Le classement par ordre croissant de sensibilité est pratiquement identique dans les deux tests (tableau 2). En conclusion, deux lots de 10 plantules, chacune produisant deux tubercules, constituent un échantillon approprié pour analyser la sensibilité d'une lignée au mildiou des tubercules (tableau 4). Le test est simple et rapide, et combiné au test sur feuille, il offre la possibilité de détecter la résistance au mildiou des feuilles et des tubercules dans la même année.相似文献