Reproduction Abstracts

Introduction: In dairy cows, post-partum endometritis caused by Gram negative bacteria (e.g. E. coli) adversely affects follicular function and is associated with subfertility. However, there is limited information of the effects of endometritis on the corpus luteum (CL). Recently, we showed that LPS dose-dependently decreased luteal endothelial cell (EC) network formation in vitro. The hypothesis tested was that CL from cows with endometritis would have reduced vascu...

Introduction: The formation of a functional corpus luteum (CL) is integral to the establishment and maintenance of pregnancy. The development of the CL requires tightly regulated angiogenesis, which is controlled by a plethora of pro and anti-angiogenic factors. Transforming growth factor B (TGFB) has been identified as a potential mediator of this process. This study tested the hypothesis that TGFB would adversely impact on endothelial cell (EC) development and reduce the ste...

In dairy cows, post-partum uterine inflammation caused by Gram negative bacteria (e.g. E. coli) suppresses follicular function and reduces fertility. LPS is an endotoxin that is present on outer membrane of Gram-negative bacteria. Furthermore, LPS is detected in follicular fluid (0.04–0.88 μg/ml) of cows with endometritis. This study tested the hypothesis that LPS would decrease the formation of luteal endothelial cell (EC) network and progesterone ...

Introduction: Luteal phase deficiency following assisted reproductive technology (ART) programmes has led to progestogen supplementation. However, there is debate over which route of progestogen administration (intramuscular or vaginal) is most beneficial and whether additional treatment with oestrogen further improves pregnancy rates. Thus, a large-scale meta-analysis was performed to investigate the benefit of these luteal phase support treatments on pregnancy outcome in wom...

Introduction: The continued decline in fertility is a multifactorial problem and has severe adverse impact on a farm’s profitability. Under-nutrition during pregnancy can subsequently affect the cardiovascular system, renal function and fertility in the offspring. This study tested the hypothesis that maternal protein restriction would adversely affect fetal ovarian development and number of germ cells.Methods: Fourteen Scottish Blackface ewes were ...

Introduction: Toll-like receptors (TLRs) are critical mediators of the host defence against pathogens, but may also directly influence reproduction. TLR signalling pathways have been identified in bovine granulosa cells. However, despite key diseases, such as mastitis, being associated with reduced luteal function, TLRs have not been extensively examined in the corpus luteum (CL). TLRs have also been implicated in tissue repair and remodelling processes critical to the rapid t...

Introduction: Periconception dietary protein can affect fertility in cattle. This study investigated the effect of dietary crude protein intervention on gene expression in granulosa cells, metabolite concentrations in follicular fluid and serum anti-Müllerian hormone (AMH) concentrations.Methods: Non-pregnant Angus cross heifers (n=320) were group fed an isocalorific low (LP 10%) or high (HP 14%) crude protein diet for >60 days prior to...

Dairy cow fertility has declined over the past 50 years coinciding with increased milk production. Uterine health is an important factor with endometritis prevalent in high-yielding dairy cows. This study assessed the association between uterine disease on reproductive performance in 78 commercial UK dairy herds. Data from 59 118 lactations (n=29 157 cows) was collected from 2000to 2009 and included presence of uterine disease, calving date, and insemination informati...

Dairy herd fertility is in decline and poses a significant economic problem, with associated animal welfare concerns. One factor that may contribute to this decline is exposure to environmental chemicals (ECs) some of which have endocrine disrupting activity and have been linked to declining fertility in other species. We hypothesised that ECs are present in bovine ovarian tissue at levels able to perturb luteal development and function. The tissue content of DEHP and a panel ...

Introduction: This study investigates the effect of dietary crude protein on the cellular composition of the 98 days bovine placenta.Materials and methods: Primiparous 14-month-old Bos. indicus cross heifers in Australia (n=350) were individually fed isocalorific high (H; 14%) or low (L; 7%) CP from day −60 prior to conception to 23 days post conception (dpc). At 23 days post-conception the two groups were further split into high ...