title: Reproductive performance and gestational effort in relation to dietary fatty acids in guinea pigs.
abstract: BACKGROUND
  Dietary saturated (SFAs) and polyunsaturated (PUFAs) fatty acids can highly affect reproductive functions by providing additional energy, modulating the biochemical properties of tissues, and hormone secretions. In precocial mammals such as domestic guinea pigs the offspring is born highly developed. Gestation might be the most critical reproductive period in this species and dietary fatty acids may profoundly influence the gestational effort. We therefore determined the hormonal status at conception, the reproductive success, and body mass changes during gestation in guinea pigs maintained on diets high in PUFAs or SFAs, or a control diet.
  
  
  RESULTS
  The diets significantly affected the females' plasma fatty acid status at conception, while cortisol and estrogen levels did not differ among groups. SFA females exhibited a significantly lower body mass and litter size, while the individual birth mass of pups did not differ among groups and a general higher pup mortality rate in larger litters was diminished by PUFAs and SFAs. The gestational effort, determined by a mother's body mass gain during gestation, increased with total litter mass, whereas this increase was lowest in SFA and highest in PUFA individuals. The mother's body mass after parturition did not differ among groups and was positively affected by the total litter mass in PUFA females.
  
  
  CONCLUSIONS
  While SFAs reduce the litter size, but also the gestational effort as a consequence, PUFA supplementation may contribute to an adjustment of energy accumulations to the total litter mass, which may both favor a mother's body condition at parturition and perhaps increase the offspring survival at birth.
authors.affiliation: Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Matthias
authors.identifier: 0000-0001-9608-6280
authors.initials: M
authors.lastname: Nemeth
authors.affiliation: Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Millesi
authors.affiliation: Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Carina
authors.initials: C
authors.lastname: Siutz
authors.affiliation: Department of Nutritional Sciences, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Wagner
authors.affiliation: Department of Nutritional Sciences, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Ruth
authors.initials: R
authors.lastname: Quint
authors.affiliation: Department of Behavioural Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.|Department of Anthropology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors.forename: Bernard
authors.initials: B
authors.lastname: Wallner
keywords: Body mass; Female reproduction; Gestation; Litter size; Polyunsaturated fatty acid; Saturated fatty acid; Total litter mass