Arginine for gestating sows and foetal development: A systematic review
For many years, the concept of functional amino acids has been used in swine nutrition (Mateo et al., 2007). The use of these nutrients during pregnancy has been widely studied due to their participation in metabolic pathways related to animal reproductive functions. Among the functional amino acids, arginine plays a significant role (Wu, 2010; Wu, Bazer, Johnson, et al., 2010). According to these authors, in addition to participation in muscle tissue protein synthesis, arginine is also a precursor of biologically active molecules, such as polyamines and nitric oxide, which favour embryonic and foetal growth and development.
However, studies evaluating the effects of arginine supplementation for gestating sows on the intrauterine development of the litter have conflicting results (Li et al., 2015; Novak et al., 2012; Quesnel et al., 2014). It is known that, in addition to dietary levels of arginine, lysine, and protein (Li et al., 2014), gestational age for supplementation (Li et al., 2010), the parity of the sow (Li et al., 2015), the litter size (Strathe, Strathe, Theil, Hansen, & Kebreab, 2015), and environmental conditions (Laspiur & Trottier, 2001) may also influence the results. To date, there is no consensus about the best way to use this amino acid in diets of gestating sows. Thus, the objective of this study was to verify the effects of dietary arginine supplementation for gestating sows on foetal development, using a systematic review of scientific papers.