Nutrient deprivation during intrauterine stage could alter fetal metabolism, leading to permanent changes in body structure, function and metabolism.
Gut health has been a term extensively used lately. However, its definition is still unclear. In humans, gut health is initially related to inflammatory diseases. On the other hand, the focus on pigs is based on disease prevention and performance maximization, through nutrient utilization and growth efficiency.
Gut health is influenced by several factors. Among them, injury during prenatal stage, compromising fetal development, can be considered the primary damage source.
There is evidence that inadequate nutrition and limited uterine capacity would be the main injury capable of compromising fetal development in swine species.
In this context, nutrient deprivation during intrauterine stage could alter fetal metabolism, leading to permanent changes in body structure, function and metabolism.
Advances in genetic improvement in pig farming have provided the generation of females with high reproductive performance, capable of conceiving numerous litters.
This fact provided an increase in the number of conceptuses (fetuses and their membranes), but the uterus size did not follow this increase, making the uterine space and placental efficiency limited.
Thus, the piglet weight at birth became increasingly heterogeneous, suggesting a negative correlation between the number of piglets and the average birth weight.
Piglets with low birth weight can represent up to 30% of a litter and are considered the main cause of reduced neonatal survival, including postnatal growth delay.
In pigs, the main cause of low birth weight is intrauterine growth restriction (IUGR), a condition in which the fetus does not reach its growth potential due to placental insufficiency. Therefore, in this species IUGR occurs naturally and severely.
In an adverse uterine environment, one of the fetal survival strategies is the redirection of blood flow to the brain to the detriment of organs such as small intestine, which compromises its normal development. This condition contributes to permanent low weight and the development of enteric diseases, increasing medication intensity and associated costs.
In this regard, in order to maximize the growth of these animals, the nutritional demand has been high at all growth stages. However, it is still necessary to expand the knowledge about the digestive and immunological capacity of the smal...