Effect of egg weight on composition, embryonic growth, and expression of amino acid transporter genes in yolk sac membranes and small intestines of the domestic pigeon (Columba livia)

Abstract

The objective of this study was to investigate the effect of egg weight on the composition of the egg, the growth of the embryo, and the expression of amino acid transporter genes in the yolk sac membranes and small intestines of the domestic pigeon (Columba livia). A total of 240 fertilized eggs were collected and divided into two groups based on the weight of the eggs, light (LE) and heavy (HE). The composition of 20 eggs from each group was measured, and the remaining eggs were weighed and placed in an incubator. On embryonic days (E) 9, 11, 13, and 15 and day of hatch (DOH), 15 embryos/hatchlings from each group were measured for embryonic growth, and samples were collected. The HE had heavier yolk and albumen weights than the LE (P < 0.01). Compared with the LE, the HE had heavier yolk-free embryonic body and yolk sac weights from E13 to DOH (P < 0.05). Additionally, the HE had larger yolk sac membrane weights from E13 to E15 (P < 0.05) and had more residual yolk sac content on DOH than those of the LE (P < 0.01). The yolk absorption was greater for the HE than for the LE from E11 to E13 (P < 0.05). Furthermore, the abundance of CAT2 and PepT1 mRNA in the yolk sac membranes was greater in the HE than in the LE on E13 (P < 0.05). Compared with the LE, the gene expression of EAAT2 in the intestine on E13 was greater in the HE, whereas the expression of EAAT3 was lower in the HE (P < 0.05). Taken together, our results suggest that egg weight influenced the composition of the eggs, embryonic development, and expression of amino acid transporter genes in the yolk sac membranes and small intestines of pigeon embryos.

EAAT3 promotes amino acid transport and proliferation of porcine intestinal epithelial cells

“…Glu absorption is mainly mediated by EAAT3 in the nervous system [16], gastrointestinal tract [5, 17] and skeletal muscle [18]. Our previous studies revealed that EAAT3 is a marker of intestinal growth during embryonic development in chicks [7, 19] and pigeons [20–22]. In addition, Glu deficiency or absorptive inhibition of EAAT3 decreased IPEC-1 cell proliferation [6].…”

Comparison of Some Relative Gene Expressions in the Yolk Sac Membrane and Small Intestine of the Embryos in the Layer Hybrid and Pure Breeds

“…However, EAAT3 gene expression in the small intestine of LW and Denizli embryos increased from E19 to E21. B 0 AT, EAAT3 and CAT1 genes are important in amino acid absorption (Chen et al, 2016). B 0 AT and EAAT3 are brush-border membrane proteins.…”

“…PepT1 is localized at the brush border membrane. Amino acids are introduced into the enterocyte as di or tri peptides via PepT1 (Chen et al, 2016;Leibach & Ganapathy, 1996). PepT1 expression was regulated in the developmental stage during the embryonic growth and its mRNA level rose from E16 to hatch (Chen et al, 2005, Gilbert et al, 2007, Speier et al, 2012.…”

“…The embryonic development is important for posthatch growth. This is influenced by breeder age, egg storage and incubation (Chen et al, 2016). Yolk sac provides the developing embryo with the nutrients required for growth and energy (Noble & Cocchi, 1990).…”

CDX2 increases SLC7A7 expression and proliferation of pig intestinal epithelial cells

“…Nutrient absorption, mediated by nutrient transporters, supports the growth of intestinal epithelial cells. Our previous studies have shown that the gene expression of SLC1A1 , SLC7A9 , and SLC15A1 in chicks [ 19 , 20 ] and SLC7A9 , SLC1A1, SLC43A2 , SLC15A1 , SLC9A2 , SLC9A3 , and SLC7A6 in pigeons positively correlates with the growth of embryonic intestines [ 21 , 22 ]. In addition, the inhibition of SLC1A1 decreased the proliferative activity of the IPEC-1 cells, as expected [ 23 ].…”