Development of the gastrointestinal tract of newborn goats under maternal feed restriction at different stages of gestation

ABSTRACT

This study evaluated how nutritional insults applied at different stages of intrauterine development affect the growth and development of total tract organs and the mRNA expression of genes that encode growth factors, tight junction proteins, digestive enzymes, and glucose transporters in the small intestine of newborn goats. Fourteen nulliparous dairy goats were assigned to one of two nutritional plans over gestation: maintenance-restriction (M-R, n = 8) – 100% of maintenance requirement from d 8-84 of gestation followed by feeding at 50% maintenance requirement from d 85 of gestation to parturition; or restriction-maintenance (R-M, n = 6) – 50% of maintenance requirement from d 8-84 of gestation followed by feeding at 100% maintenance requirement from d 85 of gestation to parturition. Fisher's least significant difference test was performed using SAS 9.4, considering a full fixed-effect model. When expressed per kg of body weight, the weights of the small intestine and total intestine were 18.7 and 18.1% lower, respectively, for R-M offspring. The lengths of the small intestine and the total intestine of the R-M newborns were 19.1 and 9.5% shorter, respectively. This group also had a lower villus height:intestinal crypt depth ratio. The R-M offspring tended to have lower Solute carrier family 5 member 1 (SLC5A1), Solute carrier family 2 member 2 (SLC2A2), and Occludin (OCLN) mRNA expressions. Therefore, feed restriction in the first half of gestation is detrimental to the second half of gestation, reducing the offspring's intestinal absorptive area but enhancing their intestinal permeability.

Keywords:
fetal programming; intestine; nutrients absorption; organogenesis; small ruminants