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31.
AB Caselles A Miro‐Moran A Morillo Rodriguez JM Gallardo Bolaños C Ortega‐Ferrusola GM Salido FJ Peña JA Tapia IM Aparicio 《Reproduction in domestic animals》2014,49(2):254-262
Apoptosis in the testis is required to ensure an efficient spermatogenesis. However, sometimes, defective germ cells that are marked for elimination during this process escape elimination in the testes, giving rise to ejaculates with increased percentages of abnormal and apoptotic spermatozoa and a high percentage of apoptotic bodies. Apoptosis markers in the ejaculate have been associated with low fertility, either in animals or humans. Therefore, the goal of this study was to investigate whether fresh equine semen contains apoptotic bodies [initially named Merocyanine 540 (M540) bodies] and to study the relationship between the quantity of these bodies and cell concentration, the volume of ejaculate, viability and motility. Moreover, we also studied whether the presence apoptotic bodies in fresh semen was related to the resistance of the stallion spermatozoa to being incubated at 37°C or being frozen and thawed. Fresh equine semen was stained with fluorescent dyes such as M540 and Annexin‐V. Active Caspase 3 was studied in fresh semen through Western blotting and immunofluorescence with a specific antibody. Sperm kinematics was assessed in fresh, incubated and thawed samples using computer‐assisted semen analysis, and viability was evaluated with the LIVE/DEAD Sperm Viability Kit. Overall, our results demonstrate for the first time the presence of apoptotic bodies in equine semen. The quantity of apoptotic bodies was highly variable among stallions and was positively correlated with Caspase 3 activity in fresh samples and negatively correlated with the viability and motility of stallion spermatozoa after the cryopreservation process. 相似文献
32.
CM Balao da Silva C Ortega Ferrusola JM Gallardo Bolaños M Plaza Dávila P Martín‐Muñoz JM Morrell H Rodriguez Martínez FJ Peña 《Reproduction in domestic animals》2014,49(6):1021-1027
Flow cytometry is considered the only reliable method for the separation of X and Y chromosome bearing spermatozoa in equines. The MoFlo SX DP sorter is highly efficient, allowing the production of foals of the desired sex. However, to achieve acceptable pregnancy rates the currently used protocol requires working with fresh semen obtained close to, or at, the sorting facility. An alternative protocol was tested during two consecutive breeding seasons. Fresh stallion semen was cooled for 20 h, during which staining with Hoechst 33342 took place. On the following day, this sample was flow sorted and compared with spermatozoa from the same ejaculate that had been sexed on the previous day. All sperm parameters evaluated remained unchanged when fresh sorted and refrigerated sorted semen were compared. Pre‐sorting storage at 5°C did not alter sperm velocities nor kinetics, viability or membrane permeability, production of reactive oxygen species, mitochondrial membrane potential or DNA fragmentation index of the sorted sample. The findings open for the possibility of using semen from stallions housed far from the sorting facilities. Processed and stained sperm could be shipped refrigerated on the previous day, sorted and inseminated on the next day. 相似文献
33.
LA Gracia‐Calvo LJ Ezquerra M Martín‐Cuervo ME Durán H Tapio JM Gallardo FJ Peña C Ortega‐Ferrusola 《Reproduction in domestic animals》2014,49(6):1043-1048
Laparoscopic hernioplasty techniques have been developed in the recent years to avoid the recurrence of inguinal hernias and to spare the testicles for breeding purposes in stallions. However, there have been no previous comprehensive and systematic studies of the reproductive outcomes and prognoses for stallions after inguinal hernioplasty. Therefore, the objective of this study was to assess the possible effects of one of these techniques (standing laparoscopic peritoneal flap hernioplasty) on the sperm production and motility characteristics of six healthy stallions that received this procedure based on 1‐year follow‐ups. There were no significant differences in the measured sperm variables (assessments based on the DSO, MOT, PMOT, VSL, VCL and VAP) during 1‐year follow‐ups. 相似文献
34.
R Lieu JPD Mittaz S Bowyer JO Breen FJ Lockman EM Murphy C Hwang 《Science (New York, N.Y.)》1996,274(5291):1335-1338
The central region of the Coma cluster of galaxies was observed in the energy band from 0.065 to 0.245 kiloelectron volts by the Deep Survey telescope aboard the Extreme Ultraviolet Explorer. A diffuse emission halo of angular diameter approximately 30 arc minutes was detected. The extreme-ultraviolet (EUV) emission level exceeds that expected from the x-ray temperature gas in Coma. This halo suggests the presence of two more phases in the emitting gas, one at a temperature of approximately 2 x 10(6) kelvin and the other at approximately 8 x 10(5) kelvin. The latter phase cools rapidly and, in steady state, would have produced cold matter with a mass of approximately 10(14) solar masses within the EUV halo. Although a similar EUV enhancement was discovered in the Virgo cluster, this detection in Coma applies to a noncooling flow system. 相似文献
35.
J Christensen-Dalsgaard W Dappen SV Ajukov ER Anderson HM Antia S Basu VA Baturin G Berthomieu B Chaboyer SM Chitre AN Cox P Demarque J Donatowicz WA Dziembowski M Gabriel DO Gough DB Guenther JA Guzik JW Harvey F Hill G Houdek CA Iglesias AG Kosovichev JW Leibacher P Morel CR Proffitt J Provost J Reiter EJ Rhodes FJ Rogers IW Roxburgh MJ Thompson RK Ulrich 《Science (New York, N.Y.)》1996,272(5266):1286-1292
Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations. 相似文献
36.
Ligia Ayala Monique Henry Maarten van Ginkel Ravi Singh Beat Keller Mireille Khairallah 《Euphytica》2002,128(2):249-259
We searched for QTLs involved in tolerance to barley yellow dwarf (BYD), a serious viral disease of small grain cereals in
two wheat populations, Opata × Synthetic (ITMI)and Frontana × INIA66 (F × I), for which marker data had previously been generated.
The populations were evaluated in replicated field trials under artificial inoculation with a BYDV-PAV-Mex isolate and under
disease-free conditions. Disease symptoms (yellowing, dwarfism and biomass reduction) were visually recorded and agronomic
traits (number of tillers,height, biomass, yield and thousand-kernel weight) were measured on five plants per plot. Phenotypic
data on all evaluated traits showed normal distribution with high correlation between visual estimates and measured values.
Heritabilities were mostly moderate to high in the 114 lines of the ITMI population, and from low to moderate in the 117 lines
of the F × I population. QTL analyses were based on genetic maps containing 443 loci for the ITMI population and 317 loci
for the F × I population. Using composite interval mapping, 22 QTLs in the ITMI population and seven in the F × I population
were detected, explaining9.8–43.3% of total phenotypic variation (σ2
P)per agronomic trait in the first population, and 4.1–13.7% in the second. Individual QTLs explained less than 15.8%of σ2
P. In the F × I population a minor QTL explaining 7% of σ2
P for yellowing was detected on the short arm of 7D, linked to leaf tip necrosis, a morphological marker for linked genes Bdv1, Yr18 andLr34. A QTL consistently detected for several traits on 2D in the ITMI population and on the short arm of group 6 chromosome(6S)
in F × I explained 10–15% of σ2
P. The large number of QTLs having mostly small effects and the continuous distribution of all evaluated traits confirmed the
polygenic nature and complexity of BYD tolerance in wheat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
37.
At the IPK Gatersleben a series of 85 bread wheat (T. aestivum)/goatgrass (Aegilops tauschii) introgression lines was developed recently. Based on the knowledge that chromosome 7D of this particular Ae. tauschii is a donor of resistance to septoria tritici blotch (Mycosphaerella graminicola), a sub-set of thirteen chromosome 7D introgression lines was investigated along with the susceptible recipient variety ‘Chinese
Spring’ (CS) and the resistant donor line ‘CS (Syn 7D)’. The material was inoculated with two Argentinian isolates of the
pathogen (IPO 92067 and IPO 93014) at both the seedlings (two leaf) and adult (tillering) stages at two locations over 2 years
(2003, 2004). The resistance was effective against both isolates and at both developmental stages, and the resistance locus
maps to the centromeric region of chromosome arm 7DS. On the basis of its relationship with the microsatellite marker Xgwm44, it is likely that the gene involved is Stb5. Stb5 is therefore apparently effective against M. graminicola isolates originating from both Europe and South America. 相似文献
38.
M. P. García Hernndez A. García Ayala B. Agulleiro A. García W. van Dijk R. W. Schulz 《Aquaculture (Amsterdam, Netherlands)》2002,210(1-4):203-218
Purified Mediterranean (M.) yellowtail luteinizing hormone-like gonadotropin (MyLH) and its β-subunit (MyLHβ) served to develop a radioimmunoassay (RIA) for MyLH. The rabbit antisera against MyLH and MyLHβ used for this purpose were tested on pituitary sections by immunocytochemistry. Anti-MyLHβ specifically detected a single type of cells, which were located at the periphery of the proximal pars distalis (PPD) and surrounding the pars intermedia (PI). Anti-MyLH, however, also recognized two other cell types, thyrotropin β-immunoreactive (ir) cells and putative follicle-stimulating hormone-like (MyFSH)-producing cells. Labeling of the two latter cell types was prevented by preabsorption of anti-MyLH with M. yellowtail pituitary glycoprotein -subunit. The standard curve for the RIA was generated using purified MyLH, 125I-labeled MyLHβ and anti-MyLHβ at a dilution of 1:70,000, which resulted in the binding of 30% of the tracer added. The standard curve ranged from 0.25 to 50 ng/ml. The midrange of the assay (ED50) was obtained with 5.48–7.87 ng LH/ml. The variation between assays was less than 15%. An average cross-reactivity of FSH in the LH RIA of 8.4% was found. Serial dilutions of M. yellowtail pituitary extracts displaced radiolabelled MyLHβ parallel to the MyLH standard. Application of the LH RIA to blood samples and pituitary cell culture medium provided physiological validation of the assay. Significant increases in LH levels were recorded after salmon GnRH treatments in vivo and in vitro. Serum LH levels from wild fish sampled at the spawning season were significantly higher than those from captive fish sampled in the same period. 相似文献
39.
Aly R Ravid U Abu-Nassar J Botnick I Lebedev G Gal S Ziadna H Achdari G Smirov E Meir A Ghanim M 《Pest management science》2011,67(12):1493-1498
BACKGROUND: Ecdysteroids are steroid hormones that control moulting and govern several changes during metamorphoses in arthropods. The discovery of the same molecules (phytoecdysteroids) in several plant species displayed a wide array of rather beneficial agricultural impact. Many representatives of the genus Ajuga plants contain phytoecdysteroids with a 5β‐7‐ene‐6‐one system exhibiting physiological activities in insects. RESULTS: By means of chromatographic (silica gel column, TLC) and LC‐MS, two major ecdysteroids (20‐hydroxyecdysone and cyasterone) have been isolated and identified from Israeli carpet bugle Ajuga iva (L.) Schreber (Lamiales: Lamiaceae) plants. Ajuga iva extract fractionated on the silica gel column yielded two fractions that showed high activity against the sweetpotato whitefly Bemisis tabaci and the persea mite Oligonychus perseae. A dose of 5 mg AI L?1 of the purely identified A. iva ecdysterone significantly reduced fecundity, fertility and survival of these pests, while commercial 20‐hydroxyecdysone at the same dose had lesser effects. CONCLUSION: The results demonstrate considerable efficacy of natural phytoecdysteroids against major agricultural pests, and suggests that these materials should be considered for potential development of friendly control agents. Copyright © 2011 Society of Chemical Industry 相似文献
40.
Ayala I Latorre R Soria F Carballo F Lopez-Albors O Buendia AJ Perez-Cuadrado E 《Journal of the American Animal Hospital Association》2011,47(4):262-267
A 3 yr old male English setter dog was presented for evaluation of a 6-wk history of intermittent diarrhea. After standard gastroduodenoscopy and colonoscopy showed normal mucosa, double-balloon endoscopy (DBE) was used via both oral and anal approaches. Gross changes consistent with inflammation in the jejunum were seen, and biopsy specimens were obtained. Histologic analysis confirmed a diagnosis of lymphocytic-plasmacytic jejunitis. Clinical remission of the disease occurred after 3 mo of therapy with prednisone, metronidazole, and a novel protein diet. Use of DBE has not been previously reported in dogs with inflammatory bowel disease, and isolated lymphocytic-plasmacytic jejunitis has not been described. The described cases of intestinal inflammatory disease diagnosed by conventional endoscopy were related to pathologic changes in the duodenum, ileum or colon, but not the jejunum. The main advantage of the DBE technique allowed examination of portions of the small intestine (jejunum) that were not commonly accessible by standard endoscopic techniques, and permitted a minimally invasive collection of biopsy samples compared with surgical biopsy. This case highlights the need to consider using DBE in animals with gastrointestinal disorders, whose symptoms are not readily explained by routine tests, conventional endoscopy, and dietary or therapeutic trials. 相似文献