Skip to main content

Table 7 Texas A&M University’s optimal ratios of true digestible amino acids in diets for chickens 1 (% of lysine in diet)

From: Dietary requirements of synthesizable amino acids by animals: a paradigm shift in protein nutrition

Amino acid

Age of chickens

 

0 to 21 d2

21 to 42 d3

42 to 56 d4

Alanine

102

102

102

Arginine

105

108

108

Asparagine

56

56

56

Aspartate

66

66

66

Cysteine

32

33

33

Glutamate

178

178

178

Glutamine

128

128

128

Glycine

176

176

176

Histidine

35

35

35

Isoleucine

67

69

69

Leucine

109

109

109

Lysine

100

100

100

Methionine

40

42

42

Phenylalanine

60

60

60

Proline

184

184

184

Serine

69

69

69

Threonine

67

70

70

Tryptophan

16

17

17

Tyrosine

45

45

45

Valine

77

80

80

  1. 1Except for glycine, all amino acids are L-isomers. Values are based on true ileal digestible amino acids.
  2. 2Patterns of amino acid composition in the ideal protein are the same for male and female chickens. The amounts of digestible lysine in diet (as-fed basis; 90% dry matter) are 1.12% and 1.02% for male and female chickens, respectively.
  3. 3Patterns of amino acid composition in the ideal protein are the same for male and female chickens. The amounts of digestible lysine in diets (as-fed basis; 90% dry matter) are 0.89% and 0.84% for male and female chickens, respectively.
  4. 4Patterns of amino acid composition in the ideal protein are the same for male and female chickens. The amounts of digestible lysine in diets (as-fed basis; 90% dry matter) are 0.76% and 0.73% for male and female chickens, respectively.