Flow Cytometry Evaluation of Testis and Sperm Cells and growth Performance of Bulls Implanted with Zeranol

Effects of preweaning zeranol implants on reproductive function and growth performance were studied in 45 Simmental-Angus bulls. At slaughter, flow cytometry measurements were made on testicular and sperm cells to determine the effects of zeranol on spermatogenesis. There were no differences in weaning or slaughter weights due to implants. Nonimplanted bulls had larger scrota1 circumferences and heavier testicular weights than bulls given one or two implants. The testes of implanted bulls had a lower proportion of developing germ cells relative to nonimplanted bulls. The DNA in sperm from implanted bulls was structurally less stable (i.e., more susceptible to denaturation) than DNA in sperm from nonimplanted bulls. Preweaning implantation with zeranol negatively affected testicular function and spermatogenesis, but did not affect growth of yearling bulls

Evaluation of Holstein Bull Sperm Quality by Flow Cytometry

Frozen semen samples from Holstein bulls were measured by the sperm chromatin structure assay (SCSA), a new procedure utilizing flow cytometry for the valuation of sperm quality. Fertility ratings of the bulls were known based on their use in artificial insemination matings. Values obtained by the SCSA were highly correlated (r= -.58 P\u3c.01 with bull fertility ratings. Results of this research indicate the SCSA may be a valuable technique for measurement of sperm cell quality and detection of suboptimal fertility in bulls

Cytochrome P4501A biomarker indication of the timeline of chronic exposure of Barrow’s goldeneyes to residual Exxon Valdez oil

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Pollution Bulletin 62 (2011): 609-614, doi:10.1016/j.marpolbul.2010.11.015.We examined hepatic EROD activity, as an indicator of CYP1A induction, in Barrow's goldeneyes captured in areas oiled during the 1989 Exxon Valdez spill and those from nearby unoiled areas. We found that average EROD activity differed between areas during 2005, although the magnitude of the difference was reduced relative to a previous study from 1996/97, and we found that areas did not differ by 2009. Similarly, we found that the proportion of individuals captured from oiled areas with elevated EROD activity ( 2 times unoiled average) declined from 41% in winter 1996/97 to 10% in 2005 and 15% in 2009. This work adds to a body of literature describing the timelines over which vertebrates were exposed to residual Exxon Valdez oil and indicates that, for Barrow's goldeneyes in Prince William Sound, exposure persisted for many years with evidence of substantially reduced exposure by 2 decades after the spill.This research was supported primarily by the Exxon Valdez Oil Spill Trustee Council

DNA Status on Thawed Semen from Fighting Bull: A Comparison Between the SCD and the SCSA Tests

P. 424-431The assessment of sperm chromatin status is compulsory in a complete spermiogram. Here we applied the sperm chromatin structure assay (SCSA) and the sperm chromatin dispersion (SCD) test to assess the chromatin status of three fighting bulls. Cryopreserved semen (two straws/bull) were analysed by duplicate after thawing and after 6 h at 37°C with and without oxidative stress (1 mm FE2+). Results (SCD: percentage of spermatozoa with halo; SCSA: SD‐DFI, %DFI and HDS) were analysed for differences between bulls and treatments, sensitivity and specificity (receiver operating characteristic curves) and repeatability (repeatability coefficients as 2SD of duplicate differences).%DFI for the three bulls was below 2% at 0 h, indicating no risk for fertility according to previous reports. It increased slightly for two of the bulls after FE2+ treatment (%DFI < 5%) and more pronouncedly for the other bull (C, %DFI∼10%), which merits further investigation. SCD rendered higher percentage of halos for bull C, but could not discriminate between samples with and without oxidizing treatment (AUC: 0.52). SCSA (%DFI) showed a high discriminating ability between treatments (AUC: 0.96). The repeatability coefficient was also higher for SCD (5.9) than for %DFI (1.8), indicating lower repeatability for SCD. Overall, %DFI might be the most useful parameter for assessing sperm chromatin on fighting bull. SCD might yield different information than SCSA, hence further research is warranted.S

Refrigerated Storage of Red Deer Epididymal Spermatozoa in the Epididymis, Diluted and with Vitamin C Supplementation

P. 212-220We have approached the problem of refrigerated storage of epididymal sperm samples from red deer by comparing three options: storing the genital (testicles within the scrotum), diluting the semen in extender or diluting the semen in extender supplemented with an anti‐oxidant. Twenty‐nine pairs of testes were collected. Spermatozoa from one of each of the pairs were immediately recovered, and diluted to 400 × 106 sperm/ml in Tris‐citrate‐fructose with 20% egg yolk. Control group was stored as such, and Anti‐oxidant group was supplemented with 0.8 mm vitamin C. The remaining epididymides and the diluted samples were stored at 5°C and spermatozoa were analysed at 0, 24, 96 and 192 h for: motility [computer‐assisted semen analysis (CASA)], acrosomal integrity, sperm viability (eosine/nigrosine staining), normal tails and chromatin status [sperm chromatin structure assay (SCSA)]. In general, seminal quality decreased with storage time. Vitamin C supported progressive motility better at 24 h (median 42% vs 23% Control and 15% epididymis), reduced the incidence of tail abnormalities and protected chromatin. Storing the semen in the epididymis slowed down motility loss, but slightly increased the occurrence of tail abnormalities and viability was lower at 192 h. However, regarding chromatin status, sperm stored in the epididymis was protected similarly to those diluted in the medium supplemented with vitamin C. Although the differences between the three groups were small, there were some advantages in supplementing the extender with vitamin C. Besides, refrigerating the epididymis may be a good option when immediate processing is not available.S

Influence of the Temperature and the Genotype of the HSP90AA1 Gene over Sperm Chromatin Stability in Manchega Rams

The present study addresses the effect of heat stress on males' reproduction ability. For that, we have evaluated the sperm DNA fragmentation (DFI) by SCSA of ejaculates incubated at 37°C during 0, 24 and 48 hours after its collection, as a way to mimic the temperature circumstances to which spermatozoa will be subject to in the ewe uterus. The effects of temperature and temperature-humidity index (THI) from day 60 prior collection to the date of semen collection on DFI were examined. To better understand the causes determining the sensitivity of spermatozoa to heat, this study was conducted in 60 males with alternative genotypes for the SNP G/C−660 of the HSP90AA1 promoter, which encode for the Hsp90α protein. The Hsp90α protein predominates in the brain and testis, and its role in spermatogenesis has been described in several species. Ridge regression analyses showed that days 29 to 35 and 7 to 14 before sperm collection (bsc) were the most critical regarding the effect of heat stress over DFI values. Mixed model analyses revealed that DFI increases over a threshold of 30°C for maximum temperature and 22 for THI at days 29 to 35 and 7 to 14 bsc only in animals carrying the GG−660 genotype. The period 29–35 bsc coincide with the meiosis I process for which the effect of the Hsp90α has been described in mice. The period 7–14 bsc may correspond with later stages of the meiosis II and early stages of epididymal maturation in which the replacement of histones by protamines occurs. Because of GG−660 genotype has been associated to lower levels of HSP90AA1 expression, suboptimal amounts of HSP90AA1 mRNA in GG−660 animals under heat stress conditions make spermatozoa DNA more susceptible to be fragmented. Thus, selecting against the GG−660 genotype could decrease the DNA fragmentation and spermatozoa thermal susceptibility in the heat season, and its putative subsequent fertility gainsPublishe

Voltaire's "Candide" and the Methodology of Dramatic Adaptation

This thesis details the search for dramaturgical methodologies of adaptation with the additional component of a creative project used to put those methodologies into practice. In particular, my research has been focused on the methodologies available for transforming static or descriptive moments of literature into compelling works of drama. My discussion on this process begins by tracing the scholarly developments in the field of adaptation studies, which have led away from what Linda Hutcheon calls “fidelity criticism” and have opened up a new vein of praxis-based research in recent years. Specifically, I trace the path to a four-step formula for the development of theory first suggested by Edward Said and later tailored to the process of adaptation by Linda Hutcheon. The formula itself advocates the balance of research and creativity, which has been an ideal framework for this thesis document. The second chapter of this thesis focuses on an application of this formula for a dramatic adaptation of Voltaire’s notorious novella Candide, or All for the Best, which presents the particular problematic of a densely philosophical novella. Candide also furnishes an interesting case study for the four-step formula as it presents both a rich historical context and a complicated narrative structure. The third and final chapter details the specific dramaturgical choices made in working with the formula to create a new adaptation entitled Survival of the Optimistic, and the implications these choices create for the adaptation process as a whole. The adaptation itself follows at the end of this thesis document