An experiment was conducted to test the hypothesis that addition of crystalline amino acids (AA) to diets during the adaptation or collection periods will not influence calculated values for apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of AA in corn and soybean meal (SBM). Seven ileal-cannulated barrows (initial body weight: 77.9 ± 2.6 kg) were allotted to a 7 × 7 Latin Square design with 7 dietary treatments and 7 periods. Dietary treatments included feeding diets based on corn or SBM without or with crystalline AA for the entire 7-d period or with crystalline AA during the adaptation period, but without crystalline AA during the collection period. An N-free diet was also used. Each experimental period consisted of 5 d of adaptation to the diets followed by 2 d of ileal digesta collection, with digesta being collected for 9 hr/d starting after feeding the morning meal. Thus, the entire experiment lasted 49 d. The AID and SID of crude protein (CP) and AA were calculated using values determined in corn or in SBM without or with crystalline AA to determine if crystalline AA influenced calculated values for AID or SID of CP and AA. Results indicated that addition of crystalline AA to diets fed during the entire 7-d period increased (P < 0.05) AID of some AA in corn and SBM. However, no differences in SID of CP and AA were observed between pigs fed the diets without crystalline AA and pigs fed the diets with crystalline AA if dietary crystalline AA were ignored in calculations of SID values. This indicates that crystalline AA were 100% absorbed before the distal ileum and did not affect calculated values for SID of AA if calculations were based only on the AA in corn or SBM. Therefore, it is concluded that crystalline AA may be added to experimental diets in digestibility experiments before and during collection periods without affecting results, if crystalline AA are disregarded in the calculation of AID or SID of AA in ingredients.

中文翻译：

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结晶氨基酸不影响猪日粮中饲料成分中氨基酸的标准化回肠消化率的计算值

进行了一项实验，以检验在适应或收集期间向日粮中添加结晶氨基酸 ( AA ) 不会影响玉米和大豆中 AA 的表观回肠消化率 ( AID ) 或标准回肠消化率 ( SID ) 的计算值的假设。膳食（SBM）。七头回肠插管手推车（初始体重：77.9 ± 2.6 kg）被分配到 7 × 7 拉丁方设计中，有 7 个饮食处理和 7 个时期。日粮处理包括饲喂基于玉米或 SBM 的日粮，在整个 7 天期间不加或加结晶 AA，或在适应期间加加结晶 AA，但在收集期间不加结晶 AA。还使用了无氮饮食。每个实验期包括 5 天的饮食适应，然后是 2 天的回肠食糜收集，从喂食早餐后开始，每天收集食糜 9 小时。因此，整个实验持续了49 d。粗蛋白( CP)的AID和SID) 和 AA 是使用在玉米或 SBM 中确定的值计算的，没有或有结晶 AA，以确定结晶 AA 是否影响 CP 和 AA 的 AID 或 SID 的计算值。结果表明，在整个 7 天期间饲喂的日粮中添加结晶 AA 增加（P< 0.05) 玉米和 SBM 中某些 AA 的 AID。然而，如果在 SID 值的计算中忽略日粮结晶 AA，则在饲喂不含结晶 AA 的日粮的猪和饲喂含有结晶 AA 的日粮的猪之间没有观察到 CP 和 AA 的 SID 差异。这表明结晶 AA 在远端回肠之前被 100% 吸收，并且如果计算仅基于玉米或 SBM 中的 AA，则不会影响 AA 的 SID 计算值。因此，可以得出结论，如果在计算成分中 AA 的 AID 或 SID 时不考虑结晶 AA，则可以在收集期之前和期间在消化率实验中将结晶 AA 添加到实验日粮中而不影响结果。