Diet- and colonization-dependent intestinal dysfunction predisposes to necrotizing enterocolitis in preterm pigs.
OBJECTIVE
Preterm birth and formula feeding are key risk factors associated with necrotizing enterocolitis (NEC) in infants, but little is known about intestinal conditions that predispose to disease. Thus, structural, functional, and microbiologic indices were used to investigate the etiology of spontaneous NEC development in preterm pigs.


METHODS
Piglets were delivered by cesarean section at 92% gestation, reared in infant incubators, and fed infant formula or colostrum every 3 hours (n = 120) until tissue collection at 1-2 days of age.


RESULTS
Clinical and histopathologic signs of NEC were observed in 57% of pigs fed FORMULA (26/46) and in 5% of pigs fed COLOSTRUM (2/38) (P < .05). Relative to COLOSTRUM, both healthy and sick FORMULA pigs had reduced intestinal villous heights, enzyme activities, nutrient absorption, and antioxidant levels and higher inducible nitric oxide synthetase activity (P < .05). In healthy pigs, mucosal microbial diversity remained low and diet independent. NEC pigs showed bacterial overgrowth, and a high mucosal density of Clostridium perfringens was detected in some but not all pigs. Germ-free conditions and antiserum against Clostridium perfringens toxin prevented intestinal dysfunction and NEC in formula-fed pigs, whereas the gut trophic factors, epidermal growth factor, and glucagon-like peptide 2 had limited effects.


CONCLUSIONS
A subclinical, formula-induced mucosal atrophy and dysfunction predispose to NEC and bacterial overgrowth. The adverse feeding effects are colonization dependent and may be reduced by factors in colostrum that include antibodies against aggressive toxins such as those of Clostridium perfringens.
Sangild
Per T
PT
Divisions of Nutrition and Reproduction, Royal Veterinary and Agricultural University, Frederiksberg, Denmark. psa@kvi.dk
Siggers
Richard H
RH
Schmidt
Mette
M
Elnif
Jan
J
Bjornvad
Charlotte R
CR
Thymann
Thomas
T
Grondahl
Marie L
ML
Hansen
Axel K
AK
Jensen
Soeren K
SK
Boye
Mette
M
Moelbak
Lars
L
Buddington
Randal K
RK
Weström
Björn R
BR
Holst
Jens J
JJ
Burrin
Douglas G
DG
D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D001707:Biopsy, Needle; D015984:Causality; D015169:Colony Count, Microbial; D003126:Colostrum; D004269:DNA, Bacterial / Q000032:analysis; D020345:Enterocolitis, Necrotizing / Q000453:epidemiology* / Q000473:pathology / Q000517:prevention & control*; D005260:Female; D041981:Gastrointestinal Tract / Q000382:microbiology; D007150:Immunohistochemistry; D041943:Infant Formula / Q000008:administration & dosage*; D007408:Intestinal Absorption / Q000502:physiology; D007413:Intestinal Mucosa / Q000382:microbiology / Q000473:pathology; D007421:Intestine, Small / Q000196:embryology / Q000378:metabolism* / Q000473:pathology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D011270:Pregnancy, Animal; D047928:Premature Birth; D011336:Probability; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013552:Swine
D004269:DNA, Bacterial