title: Modification of endometrial fatty acid concentrations by the pre-implantation conceptus in pasture-fed dairy cows.
abstract: The current study determined whether the pre-implantation conceptus modified endometrial fatty acid concentrations. Oestrus was synchronized in 14 mature lactating cows and embryos were transferred on day 7. Cows were slaughtered 10 d later, with each uterine horn flushed, the pre-implantation conceptus located, and inter-caruncular endometrial tissue collected from the gravid horn (containing the pre-implantation conceptus) and non-gravid horn. Endometrial fatty acid concentrations in the gravid and non-gravid horn were compared using linear models in restricted maxiumum likelihood. Investigations of the correlations among selected fatty acids and trophoblast weight or uterine fluid interferon-tau (IFN-τ) concentrations were also undertaken. The presence of the pre-implantation conceptus had relatively minor effects on endometrial fatty acid concentrations, but the ω6:ω3 ratio was greater and concentrations of stearic and oleic acid were slightly increased in the gravid horn. In the gravid horn, a negative linear relationship between the concentration of arachidonic acid and conceptus weight and IFN-τ concentration in the uterine luminal fluid were observed. In contrast, there was a positive relationship between concentrations of dihomo-γ-linolenic acid in the non-gravid horn and conceptus weight. In conclusion, the presence of the pre-implantation conceptus appears to modulate endometrial fatty acids, as indicated by the differences in endometrial fatty acid concentrations in the gravid and non-gravid uterine horns. The physiological implication of these local effects of the pre-implantation conceptus, on reproductive success requires further investigation.
authors.affiliation: DairyNZ Limited, Hamilton 3240, New Zealand. Susanne.Meier@dairynz.co.nz
authors.forename: Susanne
authors.initials: S
authors.lastname: Meier
authors.forename: Caroline G
authors.initials: CG
authors.lastname: Walker
authors.forename: Murray D
authors.initials: MD
authors.lastname: Mitchell
authors.forename: Mathew D
authors.initials: MD
authors.lastname: Littlejohn
authors.forename: John R
authors.initials: JR
authors.lastname: Roche
mesh_terms: D000821:Animal Feed; D000822:Animal Husbandry; D000818:Animals; D001755:Blastocyst / Q000502:physiology*; D002417:Cattle / Q000502:physiology*; D003612:Dairying; D004717:Endometrium / Q000378:metabolism*; D005227:Fatty Acids / Q000737:chemistry*; D005260:Female; D011247:Pregnancy
chemical_list: D005227:Fatty Acids