Developmental biology and reproduction

My research interests are in developmental physiology with particular emphasis on the endocrine and other mechanisms controlling intrauterine development and its long-term, postnatal consequences. My long term goal is to help identify how conditions during early life programme development and increase susceptibility to adult-onset degenerative diseases, such as Type 2 diabetes and metabolic syndrome.

Postnatal consequences of intrauterine programming

In recent years, we have begun to assess the postnatal physiological consequences of altered patterns of intrauterine development. We have shown that environmentally-induced changes in prenatal growth determine postnatal growth, fat deposition, glucose metabolism and the function of several endocrine systems including the pancreas, pituitary, adrenal and adipose tissue. Our studies have used a range of approaches to manipulate the intrauterine environment including embryo transfer, dietary manipulation, hormone administration and multiple pregnancy.

Key Publications

Effects of maternal dexamethasone treatment on pancreatic β cell function in the pregnant mare and post natal foal. ValenzuelaOA., Jellyman JK., AllenVL., Holdstock  NB., Fowden AL. (2015) Equine vet J 28 Dec. 

Neonatal glucocorticoid overexposure programs pituitary-adrenal function in ponies. Jellyman JK, Valenzuela OA, Allen VL, Forhead AJ., Holdstock NB, Fowden AL. (2015) Domest Anim Endocrinol 50: 45-49. 

Sex-associated differences in pancreatic beta cell function in healthy preweaning pony foals. Jellyman JK, Valenzuela OA., Allen VL, Holdstock NB, Fowden AL. (2014)  Equine Vet J 46; 6: 722-728. 

Glucocorticoid overexposure in neonatal life alters pancreatic beta-cell function in newborn foals. Jellyman JK, Allen VL., Holdstock NB, Fowden AL. (2013) J Anim Sci 91; 1: 104-110. 

Pancreatic endocrine function in newborn pony foals after induced or spontaneous delivery at term. Holdstock NB, Allen VL, Fowden AL. (2012) Equine vet J 44 Suppl 41:30-37.