title: Relationships between early postnatal growth and metabolic function of 16-month-old female offspring born to ewes exposed to different environments during pregnancy.
abstract: It was hypothesized that exposure of the fetus to adverse conditions in utero due to either maternal constraint or nutrition may result in developmental adaptations altering metabolism and postnatal growth of the offspring. Heavy (H) and light (L) Romney dams (G0) were allocated to ad libitum (A) or maintenance (M) nutritional regimens, from day 21-day 140 of pregnancy. Female twin-born offspring (G1) born to the dams in the four treatment groups will be referred to as HA-ewes, LA-ewes, HM-ewes and LM-ewes. At 16 months of age, offspring were catheterized and given intravenous insulin tolerance test (ITT), glucose tolerance test (GTT) and epinephrine tolerance test challenges to assess their glucose and fat metabolism in relation to their birth weight and postnatal growth. In HA-ewes, the regression coefficients of growth rates prior to puberty on insulin and glucose curves in response to GTT (InsAUCGTT) and ITT (GluAUCITT), respectively, were different from 0 (P < 0.05) and were different from the regression coefficients of HM-ewes. This may indicate that HA-ewes may have showed puberty-related insulin resistance at 16 months of age with increasing growth rates prior to puberty compared to HM- or LM-ewes. In HM-ewes, the regression coefficients of growth rates after puberty on InsAUCGTT and GluAUCITT were different from 0 (P < 0.05) and were different from those of HA-ewes. These results may indicate that offspring born to heavy dams fed maintenance during pregnancy and with greater postnatal growth rates after puberty could develop glucose intolerance and insulin resistance in later life.
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: D S
authors.initials: DS
authors.lastname: van der Linden
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: P R
authors.initials: PR
authors.lastname: Kenyon
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: H T
authors.initials: HT
authors.lastname: Blair
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: N
authors.initials: N
authors.lastname: Lopez-Villalobos
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: C M C
authors.initials: CM
authors.lastname: Jenkinson
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: S W
authors.initials: SW
authors.lastname: Peterson
authors.affiliation: 1Sheep Research Group, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: D D S
authors.initials: DD
authors.lastname: Mackenzie