Abstract: A method of preventing or treating or controlling a respiratory disease in a bovine by delivering to a lung or trachea of the bovine a composition including a polyplex having one or more mRNA encoded with a molecule selected from lycosylphosphatidylinositol (GPI) complex, antibody immunoglobulin G (IgG), antibody immunoglobulin A (IgA), antibody immunoglobulin M (IgM), antimicrobial peptide Bactenecin 5 (Bac5), antimicrobial peptide Bactenecin 7 (Bac7), bovine myeloid antimicrobial peptide (BMAP-28), lipoxin inducing enzymes, resolvin inducing enzymes, cytokines, CRISPR associated protein 13 (Cas13) enzymes, nanoluciferase (NLuc) proteins, and gene activator, catalytically dead CRISPR-associated protein 9 fused to an activator selected from the group consisting of VP64-p65-Rta transactivation domain (dCas9-VPR), VP64, and VP64-p65-HSF1 on the N terminus and SS18 on the C-terminus, and a polymer prepared by polymerizing a diacrylate monomer; one or more linker monomers; and one or more branching monomers; and

Abstract: Synthetic H2 RLN mRNA constructs that induce expression of relaxin, methods of preparing such synthetic H2 RLN mRNA constructs, and methods of administering such constructs to mammals to facilitate delivery of offspring or methods of administering such constructs to non-pregnant mammals to facilitate procedures involving the reproductive tract.