Background: Bovine milk contains extracellular vesicles (EVs) that play a role in cellular communication, acting in either an autocrine, paracrine, or an exocrine manner. The unique properties of the EVs protect the cargo against degradation. We proled the ncRNAs (non-coding RNA) present in the EVs from ve uid dairy products - raw whole milk, heat-treated skim milk, homogenized heat-treated skim milk, pasteurized homogenized skim milk, and pasteurized heavy whipping cream (four replicates each) obtained at different processing steps from a commercial dairy plant. EVs and their cargo were extracted by using a validated commercial kit that has been shown to be ecient and specic for EVs. Because many ncRNAs and the ncRNAs of bovine are less well characterized that human but are generally highly conserved, both human and Bos taurus databases were probed for putative targets.

Results: Thirty microRNAs (miRNAs), isolated from milk, with their corresponding 1546 putative gene targets have functions associated with immune response and growth and development, indicating the potential for these ncRNAs to benecially support mammary health and growth for the cow as well as neonatal gut maturation. The most abundant miRNAs were miR-125, which is involved in host bacterial and viral immune response, and human homolog miR-718 in the regulation of p53, VEGF, and IGF signaling pathways, respectively. Sixty-two miRNAs were enriched and 121 miRNAs were diluted throughout all the milk samples when compared to raw whole milk. In addition, our study explored the putative roles of other ncRNAs which included 88 piRNAs (piwi-interacting RNA), 64 antisense RNAs, and 105 longintergenic ncRNAs contained in the bovine exosomes.

Conclusion: Together, the results indicate that bovine milk contains signicant numbers of ncRNAs with putative regulatory targets associated with immune- and developmental-functions important for neonatal bovine health, and that processing signicantly increases the abundance of these ncRNA species. It is worth noting, however, that these gene regulatory targets are putative, and, though not necessary, further evidence could be generated through experimental validation.