title: Relationships among body composition, circulating concentrations of leptin and follistatin, and the onset of puberty and fertility in young female sheep.
abstract: The onset of puberty depends on the attainment of critical body mass, so should also be affected by increases in the rate of accumulation of muscle and adipose tissue. Adipose tissue and reproduction are linked by leptin. For muscle, a link has not yet been identified, although one possibility is follistatin. We assessed the relationships among circulating concentrations of follistatin and leptin and the rates of growth and accumulation of muscle and fat during pubertal development in female sheep. We used 326 animals with known phenotypic values for live weight (LW), depths of eye muscle (EMD) and fat (FAT), and known breeding values at post-weaning age for body mass (PWT) and depths of eye muscle (PEMD) and fat (PFAT). Leptin concentration was positively correlated with values for EMD, PEMD, FAT, PFAT, LW and PWT (P<0.001), whereas follistatin concentration was negatively correlated with values for EMD and PWT (P<0.001), and PEMD (P<0.01) and FAT (P<0.05). Leptin concentration was negatively related to age and positively related to live weight at first oestrus and the proportion of females that attained puberty (P≤0.05), and to fertility and reproductive rate (P<0.01). Follistatin concentration was negatively related to live weight at first oestrus and to fertility (P<0.01) and reproductive rate (P<0.05). There were positive correlations (P<0.001) between muscle accumulation and leptin concentration, and between muscle accumulation and reproductive performance. We conclude that leptin and follistatin are probably both involved in effects of accelerated accumulation of muscle and adipose tissues on the onset of puberty.
authors.affiliation: CRC for Sheep Industry Innovation and the University of New England, Armidale, NSW 2351, Australia; Department of Agriculture and Food of Western Australia, South Perth, WA 6151, Australia; The UWA Institute of Agriculture and School of Animal Biology, University of Western Australia, Crawley, WA 6009, Australia.
authors.forename: C A
authors.initials: CA
authors.lastname: Rosales Nieto
authors.affiliation: CRC for Sheep Industry Innovation and the University of New England, Armidale, NSW 2351, Australia; Department of Agriculture and Food of Western Australia, South Perth, WA 6151, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: A N
authors.initials: AN
authors.lastname: Thompson
authors.affiliation: Department of Agriculture and Food of Western Australia, South Perth, WA 6151, Australia.
authors.forename: C A
authors.initials: CA
authors.lastname: Macleay
authors.affiliation: Department of Agriculture and Food of Western Australia, South Perth, WA 6151, Australia.
authors.forename: J R
authors.initials: JR
authors.lastname: Briegel
authors.affiliation: Monash Institute of Medical Research, Monash University, Victoria 3168, Australia.
authors.forename: M P
authors.initials: MP
authors.lastname: Hedger
authors.affiliation: CRC for Sheep Industry Innovation and the University of New England, Armidale, NSW 2351, Australia; Department of Agriculture and Food of Western Australia, South Perth, WA 6151, Australia; School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia.
authors.forename: M B
authors.initials: MB
authors.lastname: Ferguson
authors.affiliation: The UWA Institute of Agriculture and School of Animal Biology, University of Western Australia, Crawley, WA 6009, Australia; Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Oxford OX3 9DU, UK. Electronic address: graeme.martin@uwa.edu.au.
authors.forename: G B
authors.initials: GB
authors.lastname: Martin
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development; D000818:Animals; D001823:Body Composition; D001835:Body Weight; D005260:Female; D005298:Fertility; D038681:Follistatin / Q000097:blood*; D020738:Leptin / Q000097:blood*; D018482:Muscle, Skeletal / Q000254:growth & development; D012741:Sexual Maturation; D034561:Sheep, Domestic / Q000254:growth & development / Q000378:metabolism
chemical_list: D038681:Follistatin; D020738:Leptin
keywords: Ewe lambs; Fertility; Follistatin; Leptin; Puberty