Levels of supplementation of inorganic selenium and vitamin E for meat quail aged 0 to 14 and 14 to 35 days
Commercial poultry feed costs correspond to approximately 70% of the total production costs (Freitas et al., 2006). However, there is a shortage of research aimed at improving the profitability of quail producers, especially in relation to vitamin and mineral supplementation of these birds.
Hussain et al. (2004) emphasize that minerals and vitamins are essential components of a balanced diet and are necessary for the metabolism and utilization of nutrients. Inorganic selenium (Se), as selenite or selenate, is the most commonly used feed supplementations for poultry (Payne & Southerm, 2005; Surai, 2002). These forms have been used in animal feed for more than 60 years (Tayeb & Qader, 2012).
Se plays a number of roles in animals, being a component of the enzyme glutathione peroxidase, which is a selenoenzyme responsible for fighting free radicals in muscle tissue, for avoiding oxidative damage (Arai et al., 1994), for acting as a modulator of the immune system (Ribeiro, Vogt, Canal, Laganá, & Streck, 2008) and the reproductive system (Gallo et al., 2003).
Vitamin E (VE) is considered an essential nutrient for growth, and maintenance of animal health, as it is involved in the processes of embryonic death and reabsorption, retinal degeneration, prostaglandin synthesis, erythrocyte haemolysis, and is especially important as a biological antioxidant (Bendich, Gabriel, & Machlin, 1986; Liu, Lanari, & Schaefer, 1995; McDowell, 1989).
Both elements have antioxidant functions, protecting plasma membranes against the toxic action of lipid peroxides where their actions act in a complementary way (Paschoal, Zanetti, & Cunha, 2003). Se is an essential component of the antioxidant enzyme glutathione peroxidase (Arai et al., 1994), while the VE participates actively in the structure of organic compounds because it is situated at the membrane level, minimizing the peroxidation of fatty acids and phospholipid components (Bou, Codony, Tres, Decker, & Guardiola, 2009). That is, they complement each other resulting in greater oxidative stability of the cells and consecutively improve the quality of the meat in the birds.
In addition to broiler chickens, some other works with Se and VE were carried out with geese (Jerysz & Lukaszewicz, 2013), partridges (Ding et al., 2016), laying hens (Zduńczyk et al., 2013) and quails (Chitra, Viswanathan, & Edwin, 2012; Łukaszewicz, Kowalczyk, Korzeniowska, & Jerysz, 2007; Mobaraki & Shahryar, 2015; Sahin & Kucuk, 2001; Sahin, Sahin, & Onderci, 2003) but in these cases with the japanese species where the main purpose was to evaluate the quality of eggs, being scarce in the literature works carried out with meat quails. According to Rostagno et al. (2011), the recommendations of Se and VE for broilers are 0.33 mg/kg and 31 IU/kg, respectively, but meat quails, being a different species from these others, have different metabolism and thus have different nutritional requirements.
In view of the above, the objective of this work was to estimate the best levels of inorganic Se and VE supplementation in meat quail rations to obtain maximum performance. In addition, the body chemical composition, carcass yield and poultry meat quality were evaluated.