Dr. Ariane Helmbrecht

INTRODUCTIONAs a nonpolar amino acid, Valine (Val) is one of the most hydrophobic amino acids (Brosnan and Brosnan, 2006). Val, leucine, and isoleucine are called branched chain amino acids due to the branched chain structures of their R groups. In animals, Val serves as a precursor for the synthesis of protein and other amino acids (Ferrando et al., 1995). As a glucogenic amino acid, Val is a sub ...

IntroductionLysine (Lys) is the second limiting amino acid (AA) in practical corn-soybean meal diets. Growth performance and proper muscle development of broiler chickens is highly dependent of an adequate dietary supply of Lys. Although all AA coded in the nucleic acid sequence are required for muscle protein synthesis, also depending on its frequency and dietary supply, Lys is the main esse ...

IntroductionBroiler diets are commonly supplemented with dry DL-methionine (DL-Met; 99% active substance), liquid methionine hydroxy analogue-free acid (MHA-FA, 88% active substance) or dry methionine hydroxy analogue-calcium salt (MHA-Ca, 84% active substance). Several broiler trials have demonstrated that the relative bioavailability (RBA) of Met hydroxy analogue products (MHA-FA or MHA-Ca) ...

The objective of this study was to determine the effect of mild coccidial vaccine challenge on standardized ileal amino acid digestibility (SIAAD) in 21- and 42-d old broilers fed a corn-soybean meal-DDGS-poultry by-product meal based diet. The study was designed as a 2 x 2 factorial arrangement of treatments with 2 ages (d 21 and 42) and 2 levels of coccidial vaccine (Coccivac®B) challenge (- ...

The basis of least-cost formulation is to rank raw materials according to both price and nutritive value and then to find the cheapest compromise meeting all constraints. Only feed formulation on basis of digestible amino acids (AA) will provide AA in an amount sufficient for the requested performance of an animal (growth, production of eggs, fertility). Additionally, the use of all ...