Justina Caldas

INTRODUCTIONDietary amino acids (AA) and crude protein (CP) have been demonstrated to affect BW, body composition, organ development, and feathering in broiler breeder pullets (Hudson et al., 2000; Ekmay, 2011; van Emous et al., 2013). Breeder pullets are fed to achieve target BW, and meeting growth objectives during the rearing phase has been related to improvements in reproductive parameters suc ...

INTRODUCTIONAmino acids (AA) and crude protein (CP) intake during the rearing phase in broiler breeders have demonstrated to affect body composition and reproductive performance in the laying period (Joseph et al., 2000; Ciacciariello and Tyler, 2013; van Emous et al., 2013, 2015a, 2015b). Modifications of these nutrients added up to the adjustment of feed allocation may alter BW (van Emous et al. ...

OverviewRenewed interest, especially in the United States, has sparked in assessing branched-chain amino acid interactions in practical diets for broilers. Indeed, as L-valine enters formulation bird nitrogen excesses are reduced as diet protein falls to the new first limiting amino acid (e.g., isoleucine, arginine, or tryptophan). For a United States based example, the result is less oilseeds and ...

Accurate estimation of the broiler’s lysine (Lys) requirement is vital because it is the second limiting amino acid (AA) in poultry diets and, when the ideal protein ratio concept is applied, the essential amino acids (EAA) are expressed as ratios to Lys. It is necessary to regularly update AA requirements for modern broiler chickens in order to accommodate their genetic progress. However, d ...

Amino acid pullet nutrition affects growth and development and it is important to evaluate potential effects on egg traits. One experiment was conducted to determine the effects of four amino acid (AA) dietary levels fed to broiler breeder pullets during the rearing phase from 5 to 24wk of age on egg characteristics. A total of 1,360 Cobb-500 slow-feathering pullets were placed in 16 floor pens (8 ...