Colostrum increases DNA fractional synthetic rate, villi growth, and cellular proliferation of the jejunum in neonatal gilt piglets.

Abstract

Adequate versus low colostrum (COL) intake promotes feed efficiency and greater growth trajectory in swine, indicating that varying COL levels likely impact nutrient absorption. This study's objective was to determine how diet type (COL vs milk replacer [MR]), and level of intake [20% vs 10% of birth body weight (BBW)] influence jejunum deoxyribonucleic acid (DNA) fractional synthetic rate (FSR), and villi growth and cellular proliferation in neonatal gilt piglets. Gilt piglets were allocated to one of the following treatments: pooled COL fed at 20% (COL20; n = 10) or 10% (COL10; n = 10) BBW, MR fed at 20% (MR20; n = 10) or 10% (MR10; n = 10) BBW, stay-on-sow (SOS) to suckle COL ad libitum (n = 9), or zero hour (ZH), euthanized immediately after birth (n = 8). Following administration of 20 mL/kg of deuterium oxide (D₂O) to metabolically label DNA, dietary treatments were either bottle fed every 2 h or SOS for 24 h, then blood and jejunum were collected. Enrichment of D₂O in serum and deoxyadenosine mass isotopomers in jejunum were analyzed using mass spectrometry to determine DNA FSR of jejunum. Additionally, a separate piece of jejunum was fixed in formalin, paraffin embedded, sectioned, mounted on slides, and stained with hematoxylin and eosin to measure intestinal morphology or immunostained with Ki67 antibody to identify proliferating cells. The responses of SOS and COL20 were similar for all variables, except DNA FSR, which was greatest in SOS compared to all treatments. Villi length, width, crypt depth, total area of villi, lamina propria area of villi, and crypt cell proliferation of MR20 did not differ from SOS or COL20. Cellular proliferation of lamina propria of villi was highest in COL20 compared to MR20, COL10, MR10, and ZH, whereas cellular proliferation of the deep lamina propria was greatest in SOS, which differed from MR20, MR10, COL10, and ZH. Although MR20 increased villi growth and cellular proliferation compared to the 10% treatments, it did not stimulate similar morphological growth and development of the jejunum when compared to response of adequate COL intake (SOS and COL20) groups.