Palma M N N, Rocha G C, Valadares Filho S C, Detmann E
Asian-Australas J Anim Sci. 2015 Nov;28(11):1624-8. doi: 10.5713/ajas.15.0068.
Rigorously standardized laboratory protocols are essential for meaningful comparison of data from multiple sites. Considering that interactions of minerals with organic matrices may vary depending on the material nature, there could be peculiar demands for each material with respect to digestion procedure. Acid digestion procedures were evaluated using different nitric to perchloric acid ratios and one- or two-step digestion to estimate the concentration of calcium, phosphorus, magnesium, and zinc in samples of carcass, bone, excreta, concentrate, forage, and feces. Six procedures were evaluated: ratio of nitric to perchloric acid at 2:1, 3:1, and 4:1 v/v in a one- or two-step digestion. There were no direct or interaction effects (p>0.01) of nitric to perchloric acid ratio or number of digestion steps on magnesium and zinc contents. Calcium and phosphorus contents presented a significant (p<0.01) interaction between sample type and nitric to perchloric acid ratio. Digestion solution of 2:1 v/v provided greater (p<0.01) recovery of calcium and phosphorus from bone samples than 3:1 and 4:1 v/v ratio. Different acid ratios did not affect (p>0.01) calcium or phosphorus contents in carcass, excreta, concentrate, forage, and feces. Number of digestion steps did not affect mineral content (p>0.01). Estimated concentration of calcium, phosphorus, magnesium, and zinc in carcass, excreta, concentrated, forage, and feces samples can be performed using digestion solution of nitric to perchloric acid 4:1 v/v in a one-step digestion. However, samples of bones demand a stronger digestion solution to analyze the mineral contents, which is represented by an increased proportion of perchloric acid, being recommended a digestion solution of nitric to perchloric acid 2:1 v/v in a one-step digestion.
严格标准化的实验室规程对于多个地点数据的有意义比较至关重要。考虑到矿物质与有机基质的相互作用可能因材料性质而异，每种材料在消化程序方面可能有特殊要求。使用不同的硝酸与高氯酸比例以及一步或两步消化法评估酸消化程序，以估计胴体、骨骼、排泄物、浓缩饲料、草料和粪便样本中钙、磷、镁和锌的浓度。评估了六种程序：硝酸与高氯酸比例为2:1、3:1和4:1 v/v的一步或两步消化。硝酸与高氯酸比例或消化步骤数对镁和锌含量没有直接或交互作用（p>0.01）。钙和磷含量在样品类型与硝酸与高氯酸比例之间呈现显著（p<0.01）交互作用。2:1 v/v的消化溶液从骨样品中回收的钙和磷比3:1和4:1 v/v比例更高（p<0.01）。不同的酸比例对胴体、排泄物、浓缩饲料、草料和粪便中的钙或磷含量没有影响（p>0.01）。消化步骤数不影响矿物质含量（p>0.01）。胴体、排泄物、浓缩饲料、草料和粪便样本中钙、磷、镁和锌的估计浓度可以使用4:1 v/v的硝酸与高氯酸消化溶液通过一步消化来进行。然而，骨骼样本需要更强的消化溶液来分析矿物质含量，这表现为高氯酸比例增加，建议使用2:1 v/v的硝酸与高氯酸消化溶液进行一步消化。
