Standardized ileal digestibility of amino acids in extruded full fat soybean fed to non-gestating, gestating, and lactating sows.

Abstract

This study was conducted to determine and compare the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in extruded full fat soybean (EFSB) fed to non-gestating, mid-gestating, late-gestating, and lactating sows. Six EFSB samples were collected from different sources. Fourteen non-gestating sows (Landrace × Yorkshire; parity 3 to 5) were fitted with a T-cannula at the distal ileum. After recovery, sows were assigned to a replicated 7 × 3 incomplete Latin square design. The diets included a nitrogen-free diet and six experimental diets (EFSB 1-6). Eight mid-gestating sows (Landrace × Yorkshire; parity 3; day 48 of gestation), eight late-gestating sows (Landrace × Yorkshire; parity 3; day 90 of gestation), and eight lactating sows (Landrace × Yorkshire; parity 3; day 6 of lactation) were all assigned to four dietary treatments in a repeated 4×3 incomplete Latin square design. The diets included a nitrogen-free diet and three experimental diets (EFSB 4-6). Results showed that there were significant differences in the AID and SID of CP and other AA in non-gestating sows (P < 0.05), the AID and SID values of EFSB 1-3 were higher than those of EFSB 4-6, and the value of EFSB 5 was the lowest. For mid-gestating sows, there were differences in the AID of methionine (EFSB 5 had a lower value than EFSB 4 and 6) (P < 0.01). For late-gestating sows, only the AID of methionine (EFSB 5 had a lower value than EFSB 4 and 6), tryptophan (EFSB 5 had a higher value than EFSB 4 and 6), and proline (EFSB 5 had a higher value than EFSB 4) was different (P < 0.05), and the SID of methionine (EFSB 4 had a higher value than EFSB 5) and tryptophan (EFSB 5 had a higher value than EFSB 4 and 6) was different (P < 0.05). The SID of histidine and valine was greater in lactation than in non-gestation (P = 0.045 and P = 0.02, respectively). The SID of isoleucine was greater in lactation than in non-gestation and gestation (P < 0.01). The SID of methionine in non-gestation was lower than in gestation and lactation (P < 0.01). The SID of cysteine was the lowest in mid-gestation (P = 0.045), and the SID of proline was greater in mid-gestation than in lactation and non-gestation (P < 0.01). In conclusion, the AA ileal digestibility of six EFSB samples from different sources was different, and the ileal digestibility of CP and most AA was not affected by the physiological stage of sows.