In mammalian species, the prenatal development of foetal tissues is programmed to result in the organization of different functions of the organism. During development, non-genetic factors are involved and act through regulatory substances. It is frequently said that the GIT represents “the largest endocrine organ in the body”. Most of these substances depend on an intricate regulatory complex increasingly recognized as a unique system having multiple aspects, including hormonal, nervous and immune ones. The link in this unique system comprises a number of substances whose task is to translate the signals. Among them, the gut regulatory peptides are considered to be substances that play a pivotal role in digestive functions. This review will deal with recent advances in the regulation of digestive functions in which the gut regulatory peptides are involved during development in calf i.e., during foetal life, after birth, during maintenance at the preruminant stage, and at weaning. This report will be devoted in particular to gut regulatory peptides as mediators of gastrointestinal (GI) growth, motility and development of secretion and adaptations. Increasing knowledge about the biological functions and mechanisms of gut regulatory peptide actions could help in managing the growth and maturation of the gastrointestinal tract (GTI), to better optimize digestive motility and productions. It is particularly important in the young to help them to better pass through such critical stages as the neonatal and weaning periods.