title: Lower Concentration of n-3 in the Red Blood Cells and Plasma of Lambs when their Dams were Fed a Diet High Compared with Low in n-6 Fatty Acids at Joining.
abstract: Feeding ewes a diet high in n-6 in late gestation can affect fatty acid concentrations in the newborn lamb. The effect of feeding ewes a high n-6 diet prior to conception and in early gestation on lamb n-6 and n-3 status has not previously been examined. The aim of the current study was to determine whether the concentration of n-6 was higher and n-3 was lower in lamb red blood cells (RBC) and plasma when Merino dams were fed a diet high in n-6 either pre-conception only or both pre-conception and in early gestation. Dams were fed a diet low (silage) or high (oats/CSM) in n-6 for either 6 weeks pre-mating only or 6 weeks pre-mating and 17 days post-mating. The fatty acid status of lamb RBC and plasma was determined following birth and compared with dam fatty acids around parturition. The concentration of lamb RBC and plasma n-3 was lower (p < 0.05) when dams received the high n-6 compared with low-n-6 diet around mating, independent of the length of time of feeding. The concentration of n-3 in lamb plasma was also higher when lambs were assessed as being likely rather than unlikely to have suckled prior to blood collection. Lamb RBC and plasma n-3 fatty acids were lower when dams were fed the high compared with the low n-6 diet for only a short time around mating. Transfer of fatty acids via the placenta and milk may account for the differences.
authors.affiliation: NSW Department of Primary Industries, Wagga Wagga Agricultural Institute, Pine Gully Rd, Wagga Wagga, NSW, 2650, Australia, edward.clayton@dpi.nsw.gov.au.
authors.forename: E H
authors.initials: EH
authors.lastname: Clayton
authors.forename: J F
authors.initials: JF
authors.lastname: Wilkins
authors.forename: G
authors.initials: G
authors.lastname: Refshauge
authors.forename: M A
authors.initials: MA
authors.lastname: Friend
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004032:Diet; D004912:Erythrocytes / Q000378:metabolism*; D015525:Fatty Acids, Omega-3 / Q000097:blood*; D043371:Fatty Acids, Omega-6 / Q000097:blood*; D005260:Female; D011247:Pregnancy; D012098:Reproduction; D012756:Sheep
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6