Amino acid digestibility in soybean meal produced in the United States, Brazil, Argentina, India, or China

Soybean meal is the premier source of high quality plant protein for pig diets. However, the nutritional value of soybean meal can vary among sources due to genetic differences in soybean varieties or differences in climate, soil type, fertilizer application, or processing conditions. It is important that these variations be documented so that producers can accurately formulate diets. Therefore, an experiment was conducted to determine if standardized ileal digestibility (SID) of crude protein and amino acids varied among sources of soybean meal from the U.S., Brazil, Argentina, India, or China.

Materials and methods

A total of 24 different samples of soybean meal were used in this study. Five samples were collected from the United States, Brazil, Argentina, and China, and four were collected from India.

Twenty-five growing barrows with an average initial body weight of 30.53 kg were equipped with a T-cannula in the distal ileum. In each of 8 periods, each barrow was fed one of 25 diets, so that there were 8 replications for each diet. One diet was an N-free cornstarch-based diet that was used to estimate basal endogenous losses of protein and amino acids. The other 24 diets were based on a mixture of cornstarch and each of the 24 sources of soybean meal.

Protein and amino acid composition

The concentration of crude protein was greatest (P < 0.05) in soybean meal sourced from Brazil and India, and least (P < 0.05) in soybean meal from China (Table 1). The mean of all indispensable amino acids was greatest (P < 0.05) in soybean meal from Brazil, the U.S., and India, and least (P < 0.05) in soybean meal from China.

Digestibility of crude protein and amino acids

The standardized ileal digestibility (SID) of crude protein and most amino acids was greater (P < 0.05) in soybean meal from the U.S. compared with soybean meal from Brazil, Argentina, and India (Table 2). There were no differences in SID of amino acids among soybean meals sourced from the U.S. and from China; however, the SID of crude protein was greater (P < 0.05) in U.S. soybean meal than in soybean meal from China. The SID of most amino acids was not different among soybean meal samples from Argentina, Brazil, and India.

Key points

  • Growing conditions and genetic differences affected nutrient composition and digestibility among samples of soybean meal from different countries.
  • Soybean meal from China contained less protein and indispensable amino acids than soybean meal from the U.S., Brazil, or India.
  • The standardized ileal digestibility of crude protein and amino acids is similar in soybean meal from U.S. and China, and generally greater in soybean meal from those countries than in soybean meal from Argentina, Brazil, and India.

 

Table 1. Concentration of crude protein and amino acids in soybean meal collected from China, Argentina, Brazil, the U.S., and India (normalized to 88% DM basis)

 

Country

 

Item

China

Argentina

Brazil

U.S.

India

SEM

P-value

 CP, %

45.1c

46.7b

49.3a

47.3b

49.5a

0.54

<0.001

 Indispensable AA, %

      Arg

3.27b

3.27b

3.41ab

3.42a

3.53a

0.05

0.088

      His

1.25c

1.33b

1.36b

1.37ab

1.41a

0.02

<0.001

      Ile

2.07d

2.16cd

2.34a

2.24bc

2.31ab

0.03

<0.001

      Leu

3.33c

3.57b

3.76a

3.66ab

3.75a

0.05

<0.001

      Lys

2.85c

2.96bc

3.05ab

3.07ab

3.12a

0.04

0.001

      Met

0.61b

0.63ab

0.64a

0.65a

0.66a

0.01

0.049

      Phe

2.20c

2.38b

2.52a

2.42ab

2.49ab

0.04

<0.001

      Thr

1.62b

1.77a

1.80a

1.78a

1.82a

0.03

<0.001

      Trp

0.65b

0.69a

0.69a

0.70a

0.67ab

0.01

0.016

      Val

2.14c

2.25b

2.40a

2.33ab

2.39a

0.03

<0.001

      Total

20.0c

21.0b

22.0a

21.6ab

22.21a

0.29

<0.001

Dispensable AA, %

      Ala

1.84c

2.00b

2. 09a

2.03ab

2.06ab

0.03

<0.001

      Asp

4.82c

5.03b

5.33a

5.22ab

5.42a

0.07

<0.001

      Cys

0.63

0.60

0.62

0.63

0.63

0.01

0.138

      Glu

7.79c

8.08bc

8.58a

8.43ab

8.70a

0.13

<0.001

      Gly

1.81d

1.93c

2.04ab

1.98bc

2.06a

0.02

<0.001

      Pro

2.07c

2.20b

2.32a

2.28ab

2.39a

0.04

<0.001

      Ser

1.93b

2.09a

2.17a

2.08a

2.18a

0.04

0.003

      Tyr

1.49b

1.68a

1.73a

1.68a

1.71a

0.04

0.002

      Total

22.4c

23.6b

24.9a

24.3ab

25.1a

0.34

<0.001

All AA

42.8c

45.1b

47.5a

46.5ab

47.8a

0.62

<0.001

Lys:CP ratio

6.22b

6.25b

6.15b

6.45a

6.29ab

0.04

0.014

a-c Means within a row lacking a common superscript letter are different (P < 0.05).

Table 2. Standardized ileal digestibility of crude protein and amino acids in soybean meal from China, Argentina, Brazil, the U.S., and India

 

Country

 

Item

China

Argentina

Brazil

U.S.

India

SEM

P-value

  CP, %

91.9b

91.1bc

90.9bc

93.8a

89.9c

0.84

<0.001

Indispensable AA, %

  Arg

96.8ab

95.6c

95.6c

96.9a

95.9bc

0.49

0.003

  His

93.5a

92.1b

92.1b

93.8a

92.3b

0.61

0.002

  Ile

92.6ab

91.6b

91.7b

93.4a

91.5b

0.59

0.004

  Leu

92.3ab

91.0c

91.2bc

92.9a

90.9c

0.61

0.001

  Lys

92.1ab

90.0c

90.6bc

92.9a

90.8bc

0.79

0.002

  Met

94.4ab

93.5bc

93.6abc

94.7a

92.7c

0.54

0.007

  Phe

92.5ab

90.9c

91.6bc

93.0a

91.4bc

0.59

0.001

  Thr

90.2a

88.5b

88.4b

90.8a

88.2b

0.82

0.004

  Trp

93.7ab

93.0b

92.6bc

94.3a

91.7c

0.56

<0.001

  Val

90.6ab

89.3bc

89.0c

91.4a

88.9c

0.74

0.002

Mean

92.9a

91.4b

91.6b

93.4a

91.5b

0.62

0.001

Dispensable AA, %

  Ala

91.7a

89.9b

89.9b

92.5a

89.5b

0.91

0.002

  Asp

90.2a

88.6b

88.7b

91.1a

89.8ab

0.81

0.003

  Cys

86.3a

81.5b

81.6b

86.2a

83.6ab

1.47

<0.001

  Glu

90.9ab

88.7c

89.4bc

91.7a

90.9ab

0.91

0.002

  Gly

93.8ab

92.3bc

90.5c

96.1a

91.9bc

1.66

0.012

  Ser

93.8ab

92.5b

91.0c

94.2a

92.3bc

0.64

<0.001

  Tyr

92.0ab

91.0bc

90.5c

92.8a

91.1bc

0.57

0.003

Mean

97.0ab

95.3c

94.8c

97.7a

95.6bc

0.34

0.002

All AA

94.9ab

93.4c

93.3c

95.6a

93.6bc

22.7

0.002

a-c Means within a row lacking a common superscript letter are different (P < 0.05).

This report is based on unpublished research by Vanessa Lagos and Hans H. Stein.

Authors: 
Publication Type: