Fish sperm cryopreservation is considered as a valuable technique for artificial reproduction and genetic improvement (Chao & Liao, 2001; Kopeika et al., 2007; Rana, 1995; Suquet et al., 2000). Semen quality must be monitored when attempts are made to increase the efficiency of artificial fertilization, to cryopreserve only sperm of high quality, and to evaluate frozenthawed sperm. Cryopreserve...

Fertilization at increased times after ovulation is associated with poor reproductive outcomes. This study examines the effects of post-ovulatory ageing on egg membrane function through analyses of mouse eggs collected at 13 and 22 h post-HCG ('young' and 'aged' eggs, respectively). Experiments in which fertilized zona pellucida-free young and aged eggs are challenged with additional sperm reve...

Ocean iron fertilization is an approach to increase CO2 sequestration. The Indo-German iron fertilization experiment "LOHAFEX" was carried out in the Southern Ocean surrounding Antarctica in 2009 to monitor changes in bacterial community structure following iron fertilization-induced phytoplankton bloom of the seawater from different depths. 16S rRNA gene libraries were constructed using metage...

The nature of subfertility due to the male or inseminate is as complex as that of the female. Fertilization failure or failure in embryogenesis are both documented to be of seminal origin. Males also differ in the numbers of sperm required to reach their maximum fertilization rate. Males requiring more sperm would be considered to have compensable seminal deficiencies. These include a number of...

Fertilization involves a series of cellular interactions culminating in the fusion of gamete membranes, creating a zygote and then an embryo. During the process of human fertilization in vivo or in conventional in vitro fertilization (IVF), sperm must be capable of undergoing the acrosome reaction, binding to the zona pellucida (ZP), and penetrating the ZP to fuse with the oolema. The key role ...

Disentangling the relative roles of males, females and their interactive effects on competitive fertilization success remains a challenge in sperm competition. In this study, we apply a novel experimental framework to an ideally suited externally fertilizing model system in order to delineate these roles. We focus on the chinook salmon, Oncorhynchus tshawytscha, a species in which ovarian fluid...

In pigs, the efficiency of embryo production after intracytoplasmic sperm injection (ICSI) is still low because of frequent failure of normal fertilization, which involves formation of two polar bodies and two pronuclei. To clarify the reasons for this, we hypothesized that ICSI does not properly trigger sperm-induced fertilization events, especially intracellular Ca2+ signaling, also known as ...