1,721,014 research outputs found
Tecnologie di inseminazione artificiale: inseminazione artificiale intrauterina ed embryo transfer nei piccoli ruminati: sviluppi tecnici e possibilità applicative nella pecora di razza sarda. Alghero, 17-19 Maggio 2007, pp. 174-80
No full textSafety in Assisted Reproductive Technologies: Insights from Gene Expression Studies During Preimplantation Development
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
In vitro viability and fertilization rates of cryopreserved semen collected from european mouflons of different ages
No full textThe effect of co-culture on the development of in vitro matured equine oocytes after intracytoplastic sperm injection
No full textIt is clear that, in the horse, there are many weak links in the process of in vitro embryo production; an optimal culture system for equine oocytes does not exist, and related data are conflicting. Therefore, the ability of 3 different culture systems to support embryonic development of ICSI horse oocytes was examined. Oocytes (n = 261) suitable for culture were collected from 55 ovaries and divided, according to cumulus morphology, into 2 categories: expanded cumulus and compacted cumulus. Oocytes with expanded and compacted cumulus were cultured for in vitro maturation in TCM 199 + 10% FCS + 0.1 iu/ml FSH/LH at 38.5degreesC under 5% CO2 in air for 24 and 40 h, respectively. Oocytes (n = 149) reached metaphase II and were subjected to ICSI with frozen semen and then incubated in 3 different culture systems: A) TCM 199 + 10% FCS alone or B) on granulosa cell monolayer, C) SOF + MEM aminoacids + 0.8% BSA. Cultural conditions were 39degreesC and 5% CO2 in air for A and B, while a gas mixture (5% CO2, 5% O-2, 90% N-2) was used for C. The fertilisation rate was 32%. The cleavage rate in Group A was 74.4% (32/43); 18 embryos reached 2-6 cell stage, eight 8-16 cell, four 16-32 cell and two >32 cell. In Group B, the cleavage rate was 73.5% (36/49) with better. results in embryonic development; 14 reached 2-6 cell stage, eighteen 8-16 cell, twelve 16-32 cell and five >32 cell. In Group C, the cleavage rate was significantly lower then in A and B; only 15 of 47 ICSI oocytes (39.1%) cleaved with maximum development to 2-6 cell stage. The remaining oocytes (68.1%) degenerated during culture. In conclusion, IVM horse oocytes can be fertilised in vitro with high efficiency with ICSI and co-culture systems showed to be superior in supporting in vitro embryo culture compared to simple ones. The identification of the factors beneficial to in vitro embryo development provided by the somatic cells could be important to optimise the embryo culture systems for equine embryos
Effect of cadmium on the development and DNA synthesis of mouse embryos cultured in vitro
No full textComparison between ejaculated and epididymal stallion sperm cryopreserved with the pellet method
No full textIn order to understand the freezability of epididymal sperm and its
fertilising potential we compared the membrane integrity and the
capacity to bind to the zona pellucida of frozen/thawed epididymal
and ejaculated sperm. Epididymal semen (EpS) was harvested by
flushing the epididymal tails of the testis obtained by standing
castrations of 3-year old colts while ejaculated semen (EjS) was
collected by artificial vagina. Semen was cryopreserved with the pellet
method. Sperm viability and acrosome integrity were evaluated after
thawing by incubating spermatozoa with propidium iodide and FITCPSA.
Fertilising potential was assessed by glycerol-Hoechst staining of
IVM horse and ovine oocytes coincubated with spermatozoa for 24 h.
After thawing both EpS and EjS presented 50% viability, but a
significant difference (Chi-Square test) was evidenced in the percentage
of live acrosome reacted spermatozoa (EpS: 6%; EjS: 36.1%;
p < 0:001). Zona binding test both with horse (EpS: 0.50.5; EjS:
0.30.5; p1⁄40.285) and ovine (EpS: 57.5; EjS: 3.65.6; p1⁄40.246)
oocytes did not revealed any significant difference (ANOVA) between
EpS and EjS. The results suggest that epididymal stallion spermatozoa
can be cryopreserved successfully with a better membrane integrity and
an equal capacity to bind to the zona pellucida in vitro compared to
ejaculated spermatozoa
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