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The effect of in ovo threonine (Thr) supplementation on the ileal expression of glucose, peptide and amino acid transporters was assessed in Salmonella Enteritidis‐challenged broiler chicks. At 17.5 days of incubation, fertile eggs were supplemented in the amniotic fluid with sterile saline or 3.5% threonine. Hatchlings were individually weighed, and Salmonella Enteritidis negative status was confirmed. At 2 days of age, half of the birds of each group were inoculated with sterile nutrient broth or Salmonella Enteritidis inoculum. Relative expression of sodium‐dependent glucose transporter 1 (SGLT1), glucose transporter 2 (GLUT2), di‐ and tri‐peptide transporter 1 (PepT1) and alanine, serine, cysteine, threonine transporter (ASCT1) was assessed at hatch, 2 and 9 days of age, i.e., before inoculation and 7 days post‐inoculation (dpi). At 9 days of age (7dpi), threonine increased SGLT1 and GLUT2 expression, whereas GLUT2 expression decreased in Salmonella‐challenged birds. There was a significant interaction between threonine and Salmonella for PepT1 and ASCT1. Threonine increased PepT1 expression only in non‐challenged birds. In addition, in ovo supplementation increased expression of ASCT1 regardless of post‐hatch inoculation; Salmonella inoculation resulted in decreased expression of ASCT1 only in supplemented birds. The results suggest that while intra‐amniotic threonine administration in broiler embryos increases the expression of genes related to the absorption of monosaccharides and amino acids, Salmonella challenge may negatively affect the expression of protein related transporters in the ileum of broilers. [ABSTRACT FROM AUTHOR]

This paper investigates the geometrical, electronic, and optical properties of a Ga24N24H46 nanoparticle using Density Functional Theory (DFT). The results show that this nanoparticle maintains geometrical parameters very similar to those of the GaN crystal, although it was noticed that the bond length along the direction [0001] of the Ga24N24H46 nanoparticle is smaller than those of the base of the tetrahedron, which is the opposite of what occurs in the crystal. The bandgap of the passivated nanoparticle calculated with DFT is greater than that of the crystal, while an estimate for the hydrogen-free Ga24N24 structure shows a much lower bandgap, in accordance with the literature. The simulation of the optical absorption spectra via Time-Dependent DFT allowed the association of the spatial shape of electronic orbitals with particular transition energies. The highest occupied (HOMO) and lowest unoccupied (LUMO) electronic levels are located on the (0001) and (000-1) surfaces of the particle, respectively, showing that the passivation of GaN nanoparticles should maintain its known photocatalytic activity, and that transition probability between those surface states is relatively low as compared to the HOMO-4 and LUMO transitions at 4.16 eV. Results are compared with the available experimental data. [ABSTRACT FROM AUTHOR]