Semen molecular and cellular features: these parameters can reliably predict subsequent ART outcome in a goat model

Currently, the assessment of sperm function in a raw or processed semen sample is not able to reliably predict sperm ability to withstand freezing and thawing procedures and in vivo fertility and/or assisted reproductive biotechnologies (ART) outcome. The aim of the present study was to investigate which parameters among a battery of analyses could predict subsequent spermatozoa in vitro fertilization ability and hence blastocyst output in a goat model. Ejaculates were obtained by artificial vagina from 3 adult goats (Capra hircus) aged 2 years (A, B and C). In order to assess the predictive value of viability, computer assisted sperm analyzer (CASA) motility parameters and ATP intracellular concentration before and after thawing and of DNA integrity after thawing on subsequent embryo output after an in vitro fertility test, a logistic regression analysis was used. Individual differences in semen parameters were evident for semen viability after thawing and DNA integrity. Results of IVF test showed that spermatozoa collected from A and B lead to higher cleavage rates (0 < 0.01) and blastocysts output (p < 0.05) compared with C. Logistic regression analysis model explained a deviance of 72% (p < 0.0001), directly related with the mean percentage of rapid spermatozoa in fresh semen (p < 0.01), semen viability after thawing (p < 0.01), and with two of the three comet parameters considered, i.e tail DNA percentage and comet length (p < 0.0001). DNA integrity alone had a high predictive value on IVF outcome with frozen/thawed semen (deviance explained: 57%). The model proposed here represents one of the many possible ways to explain differences found in embryo output following IVF with different semen donors and may represent a useful tool to select the most suitable donors for semen cryopreservation

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

How to Live with Dinosaurs: Ecosystems Across the Mesozoic

We continue our trip back in time through the Mesozoic, visiting several different ecosystems across the planet. Each of these was strongly influenced by the continental breakup from a single landmass into several tectonic plates and associated landmasses during this period. We will visit localities on several continents, observe how their vertebrate faunas changed over time, and what external factors might have contributed to these differences. During the Cretaceous, we visit the Iberian Peninsula, where hadrosauroids replaced titanosaurs as the most abundant dinosaur taxon. On the other side of the planet, a succession of geologic formations in Australia shows a gradual change from aquatic to terrestrial faunas resulting from sea-level changes of a now non-existent inland ocean. A visit to two polar ecosystems indicates possible mutual exclusion between amphibians (temnospondyls) and reptiles (crocodylomorphs), because they occupied similar ecological niches. Observing the record of Cretaceous landscapes in what is now Mongolia shows how changes in environment and climate correlate with changes in faunal composition. Heading back, we check if there are distinct differences in vertebrate diversity in space and time in the Late Jurassic of North America. Then we move south, to Argentina, and back to the Middle and Early Jurassic. Here, we will try to understand where these Late Jurassic faunas originated and what influence the fragmentation of the supercontinent Pangea had on their evolution and diversity. Finally, we will stop our trip in the Late Triassic of Central Europe, examining a typical vertebrate fauna from the time when dinosaurs began their domination of the planet