Assessment of the usage of biodegradable polymeric matrix in vaginal devices to sustain progesterone release in cows.

The usage of timed artificial insemination (TAI) at a low cost leading to better reproductive rates has been the aim of several research groups in the field. Usually during TAI protocols, sustained progesterone (P ) release devices are employed. Most devices are constituted of a nylon skeleton covered with a silicon layer with P .

Fetal-maternal interactions in the synepitheliochorial placenta using the eGFP cloned cattle model.

Background: To investigate mechanisms of fetal-maternal cell interactions in the bovine placenta, we developed a model of transgenic enhanced Green Fluorescent Protein (t-eGFP) expressing bovine embryos produced by nuclear transfer (NT) to assess the distribution of fetal-derived products in the bovine placenta. In addition, we searched for male specific DNA in the blood of females carrying in vitro produced male embryos. Our hypothesis is that the bovine placenta is more permeable to fetal-derived products than described elsewhere.

Treatment of nuclear-donor cells or cloned zygotes with chromatin-modifying agents increases histone acetylation but does not improve full-term development of cloned cattle.

Although somatic cell nuclear transfer (SCNT) is a promising tool, its potential use is hampered by the high mortality rates during the development to term of cloned offspring. Abnormal epigenetic reprogramming of donor nuclei after SCNT is thought to be the main cause of this low efficiency. We hypothesized that chromatin-modifying agents (CMAs) targeting chromatin acetylation and DNA methylation could alter the chromatin configuration and turn them more amenable to reprogramming.

Serum-starved apoptotic fibroblasts reduce blastocyst production but enable development to term after SCNT in cattle.

Cell cycle synchronization by serum starvation (SS) induces apoptosis in somatic cells. This side effect of SS is hypothesized to negatively affect the outcome of somatic cell nuclear transfer (SCNT). We determined whether apoptotic fibroblasts affect SCNT yields.