Although embryo transfer technology has been used commercially in cattle for many years, the inefficiency of oestrus detection, especially in recipients, has limited the widespread application of this technology. The most useful alternative to increase the number of recipients utilised in an embryo transfer program is the use of protocols that allow for embryo transfer without the need for oest...

although the mechanisms under which sex ratio is controlled in nature remain unknown, researchers have attempted to treat sperm in an effort to predetermine the sex of the offspring. the methods of sperm separation that have been repeatedly reported to isolate fractions rich in x- or y-chromosome bearing sperm are serum albumin gradient swim-up and flow cytometry. however, the ability of the se...

The technique of embryo transfer is very crucial and great attention and time should be given to this step. In order to optimize the embryo transfer technique, several precautions should be taken. The first and most important is to avoid the initiation of uterine contractility. This can be achieved by the use of soft catheters, gentle manipulation and by avoiding touching the fundus. Secondly, ...

In the past decade, assisted reproductive technologies (ART) such as oocyte transfer, intracytoplasmic sperm injection (ICSI), and nuclear transfer (cloning) have become effective enough for clinical use. ART such as oocyte transfer and ICSI allow production of foals from mares that cannot provide an embryo by standard embryo-transfer procedures. For the equine practitioner, application of ART ...

The main variables that affect nidation are related to uterine receptivity, embryo quality and the efficiency of embryo transfer. Embryo transfer is the critical step in assisted reproductive technology; with rigid catheters, contamination with blood, mucus or bacteria, increased contraction waves of the myometrium, and the level of difficulty in introducing the catheter inside the uterine cavi...

Sir, With interest we read the article of Henningsen et al., who compared pregnancy outcomes in singleton pregnancies after ART to singleton pregnancies that were conceived naturally. The authors report a significantly increased risk of stillbirth after ART before a gestational age of 28 weeks. They conclude that in view of the fact that the increased stillbirth risk was observed before 28 week...

Data were obtained from 1,908 pregnancies resulting from bovine embryo transfer procedures. Responses examined included sex ratio, fetal, neonatal and preweaning death losses, birth weight and calving assistance. The sex ratio for 1,751 embryo transfer calves examined was 51.11% males. Cows older than 10 yr that had become repeat breeders produced more (P less than .05) male calves than other d...

Variability in the cultivated germplasm for economic traits such as resistance to rice tungro virus, sheathblight, yellow stem borer, drought and salt tolerance is limited. This necessitated search for the genes in secondary and tertiary gene pool of genus Oryza. Fortunately, wild species are an important reservoir ofuseful genes for resistance to major disease, pest and tolerance t...

Intraspecific and interspecific embryo transfer in domestic South American camelids is developing into a well-established technique. Reports reveal many benefits of using reproductive biotechnologies to allow rapid propagation of alpacas and llamas of high genetic merit (e.g., high fiber quality, preserve color variation). The objective of this review is to provide up-to-date information about ...

BACKGROUND Embryo culture media used for IVF treatment might affect fetal growth and thus birthweight of the newborns. METHODS A retrospective study was conducted in South China using data from 2370 singleton neonates born after IVF/ICSI between 2009 and 2012. Two culture media, i.e., either Vitrolife or SAGE were used as embryo culture media during the study period. Neonates' birthweights we...