Reproduction Abstracts

Endometrial function is orchestrated by endogenous ovarian steroid hormones, oestradiol (E) and progesterone (P). P plays a crucial role in the functional modification of the endometrium in preparation for pregnancy (differentiation of stromal fibroblasts, maturation of spiral arterioles and influx of immune cells). In the peri-menstrual phase cyclical tissue ‘injury and repair’ in the local endometrial environment is a consequence of P-withdrawal which initiates a c...

Background: Uterine natural killer (uNK) cells are a phenotypically distinct population of tissue-resident immune cells that are reported to regulate vascular remodelling within the endometrium. The mechanisms that control accumulation of uNK cells in the endometrium remain unresolved although there is evidence to suggest that homing and differentiation of peripheral blood NK (pbNK) cells may contribute to the rapid increase in cell numbers during the secretory phase of the me...

Many studies demonstrating that the environment a pregnant female experiences can have profound and sometimes persistent effects on offspring development use extreme experimental perturbations which do not reflect the range of environments a pregnant female is actually likely to experience. We have assessed offspring reproductive development following treatments designed to reflect husbandry and management conditions that pregnant sheep or pigs encounter. Female offspring of s...

Introduction: This study determined whether the way in which pregnant ewes were handled affected gonad development in their offspring.Methods: Twin-bearing Scottish Blackface × Border Leicester ewes were either handled minimally (control, C, n=20), positively (predictable timings, soft vocal tones etc. P, n=20) or negatively (random timings, shouting and whistling etc. N, n=20) between day 65 and 100 of pregnancy. Followin...

Introduction: Following IVF, blastocysts produced from oocytes recovered from gilts fed a high fibre diet for the preceding 19 days contained more cells than blastocysts from oocytes of control-fed gilts. Oocytes were collected on day 19 of the gilts’ third oestrous cycle and matured in 10% of their own follicular fluid (FF), suggesting that FF may confer the reproductive benefits. The current study compared the protein composition of pooled FF from six high fibre-fed pig...

Background: The human endometrium is a dynamic, multi-cellular sex steroid-dependent tissue subject to cyclical episodes of breakdown (menses), repair and regeneration. The mechanisms responsible for initiation of menses are well characterised; the molecular and cellular changes responsible for rapid repair are poorly understood. Re-epithelialisation of the tissue is thought to involve contributions from both the stromal and epithelial compartments. A role for androgens in end...

Introduction: Menstruation is an inflammatory process characterised by tissue breakdown, bleeding and recruitment of leukocytes. Resolution of this inflammation at menses is critical both to limiting tissue damage and to efficient repair. Apoptosis and clearance of apoptotic cells are necessary for this process, and are thought to involve neutrophils.Our aims were to (i) delineate neutrophil numbers and identify apoptosis in peri-menstrual endometrium an...

Introduction: This study compared uterine and placental expression of genes implicated in placental attachment and angiogenesis in two prolific (hLW and MS) and one control (LW-LD) pig breeds.Methods: Placental and endometrial tissues supplying the smallest and a normal-sized foetus within the same litter were collected from five LW-LD, five hLW and four MS gilts on days 40–45 of pregnancy. RNA was isolated and qPCR for SPP1, VEGFA...

In photoperiodic species, remodelling of pituitary microvasculature appears to play a key role in the regulation of the annual reproductive cycle. Recent studies have revealed seasonal changes in the vascular loops of the ovine pituitary stalk. Microvasculature remodelling is under the control of pro-angiogenic (VEGF165a) and anti-angiogenic (VEGF165b) isoforms of vascular endothelial growth factor (VEGF). Here, we examined the differential expression of ...

This study determined whether variation (representative of normal UK farm conditions) in pregnant ewe management is sufficient to alter the programing of the male reproductive axis. Between days 85 and 138 of pregnancy, twin-bearing ewes were managed to either mimic ‘poor husbandry’ (PH) with a high stocking density, reduced feeding space and repeated social mixing or according to ‘best practice’ (BP) with a lower stocking density, longer feed troughs, and ...