title: Formula induces intestinal apoptosis in preterm pigs within a few hours of feeding.
abstract: BACKGROUND
  Nutrition regimens influence postnatal small intestinal development, which shows prominent changes after 6 hours of suckling. Such influences are particularly important in preterm neonates as inappropriate feeding responses may predispose to gastrointestinal disorders such as necrotizing enterocolitis (NEC). The authors investigated the early morphological responses to enteral feeding, prior to the time period when a large proportion of preterm pigs normally develop clinical NEC symptoms.
  
  
  METHODS
  Preterm piglets (106-107 days of gestation) were fed parenteral nutrition (PN) for 2 days with or without a subsequent 8-hour or 17-hour period of enteral nutrition (EN) with sow's colostrum or formula. Another group of piglets was delivered at 108-109 days of gestation and used for comparison to PN pigs before enteral feeding. Stereological measurements of the mucosal surface density and the volume densities of the tunica mucosa, tunica muscularis, proliferative, and apoptotic cells were made and related to microscopical NEC-lesion score. In addition, villus length and crypt depth were measured.
  
  
  RESULTS
  PN-fed piglets showed minimal PN-induced mucosal atrophy, although their crypts were deeper, together with lower cell proliferation and higher apoptotic indices, than newborn (NB) unfed piglets. After PN, enteral feeding with colostrum, for just 8 hours, induced a rapid increase in the mucosal volume density while formula feeding was associated with an elevated number of both proliferating and apoptotic cells and a higher NEC lesion score than PN- or colostrum-fed pigs.
  
  
  CONCLUSIONS
  Enteral feeding of formula, for only a few hours, induces rapid enterocyte turnover and mucosal structural changes that may predispose to later development of NEC.
authors.affiliation: Laboratory of Veterinary Anatomy and Embryology, Department of Veterinary Medicine, University of Antwerp, Belgium.
authors.forename: Marijke
authors.initials: M
authors.lastname: Oste
authors.forename: Els
authors.initials: E
authors.lastname: Van Haver
authors.forename: Thomas
authors.initials: T
authors.lastname: Thymann
authors.forename: Per
authors.initials: P
authors.lastname: Sangild
authors.forename: André
authors.initials: A
authors.lastname: Weyns
authors.forename: Christa J
authors.initials: CJ
authors.lastname: Van Ginneken
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis; D049109:Cell Proliferation; D003126:Colostrum; D004750:Enteral Nutrition / Q000009:adverse effects*; D020345:Enterocolitis, Necrotizing / Q000209:etiology* / Q000473:pathology; D005260:Female; D005526:Food, Formulated / Q000009:adverse effects*; D007413:Intestinal Mucosa / Q000166:cytology / Q000473:pathology*; D007421:Intestine, Small / Q000166:cytology / Q000473:pathology*; D010288:Parenteral Nutrition; D011247:Pregnancy; D013552:Swine