Reproductive Aging Influences Ovarian Function in Beef Cows

Anti-Müllerian Hormone (AMH) has been associated with follicle number and age of the ovary. Therefore, our hypothesiswas that AMH was a biomarker for both follicle number and ovarian function in the beef cow. Ovaries were collected by flank laparotomy. The number of follicles increased as cows aged from 1.5 to 6 years and began to decrease thereafter; however, the size of the ovary continued to increase with advanced age. Expression of the AMH gene increased with increasing follicle number in 2-year-old beef cows. These results suggest that heifers with larger ovaries will have greater numbers of follicles and greater productivity, allowing them to stay in the production herd longer. AMH could be used to identify heifers of high reproductive potential at a very young age

Selective signalling of alcohols by a molecular lattice and mechanism of single-crystal-to-single-crystal transformations

Single-crystal-to-single-crystal (SCSC) transformations of molecular materials involving exchange of lattice molecules are becoming commonplace and very relevant in areas like chemical sensing or the pharmaceutical sector. Spin crossover (SCO) complexes could be great candidates to act as molecular chemical sensors using spin switching to signal detection. We describe here the capacity of the Fe(ii) molecular material [Fe(bpp)(H2L)](ClO4)2·C3H6O (bpp and H2L are 2,6-bis-(pyrazol-3-yl)-pyridine type ligands) to have its lattice acetone molecules replaced by certain selected alcohols from the gas phase (MeOH, EtOH or nPrOH but not iPrOH), signalling the process by a spin transition that also changes the colour of the crystals. The magnetic response of the signalling complex depends on the chain length of the alcohol, allowing selective detection. As these molecular exchanges are SCSC processes, the structures of the alcoholates obtained have been determined by single crystal X-ray diffraction (SCXRD). The removal of n-propanol from its host lattice has been quenched in operando at various intermediate stages and studied by SCXRD to unveil crucial details of the mechanism of this SCSC transformation

High-temperature surface enhanced Raman spectroscopy for in situ study of solid oxide fuel cell materials

In situ probing of surface species and incipient phases is vital to unraveling the mechanisms of chemical and energy transformation processes. Here we report Ag nanoparticles coated with a thin-film SiO2 shell that demonstrate excellent thermal robustness and chemical stability for surface enhanced Raman spectroscopy (SERS) study of solid oxide fuel cell materials under in situ conditions (at ???400 ??C).close3

Oocyte mRNA and Follicle Androgen Levels Associated with Fertility

The environment that the oocyte develops in (follicle) and the mRNA that is produced (mRNA abundance) during development were examined. Androgen levels within the follicle were higher in heifers (≤ 2 years) that never established a pregnancy compared to cows that stayed in the herd at least 3 years and had at least one successful pregnancy. These high androgen levels were associated with increased abundance of several candidate mRNAs in the cumulus-oocyte complex (COC), which includes the oocyte and somatic cells immediately surrounding the oocyte, isolated from the dominant follicle. The data suggest that androgen levels represent a marker for oocyte quality which could be used to select for females to retain in the herd

Granulosa Cell Gene Expression is Altered in Follicles from Cows with Differing Reproductive Longevity

Heifers and cows that were culled from the herd due to failure to become pregnant were categorized into groups with low (\u3c 2 year), moderate (\u3e2 and \u3c 6 year) or high (≥ 6 year) fertility. Antral follicle counts were numerically lower in the low group and increased in the moderate- and high-fertility group. Granulosa cells from dominant follicles in moderate- and high-fertility cows had a greater ratio of Vascular Endothelial Growth Factor 164 (VEGF164) to VEGF164B compared to the low-fertility cows. Furthermore, there was more CARTPT in granulosa cells from subordinate follicles in moderate- and high-fertility cows than low. Gene expression is altered in granulosa cells from cows differing in fertility, suggesting these are candidate genes that may be used as markers to assist in determining reproductive longevity in beef cows