Hall L E, Shirley R B, Bakalli R I, Aggrey S E, Pesti G M, Edwards H M
Department of Poultry Science, The University of Georgia, Athens, Georgia 30602-2772, USA.
Poult Sci. 2003 Mar;82(3):414-8. doi: 10.1093/ps/82.3.414.
An experiment was conducted to compare two common methods of estimating bone ash from growing broiler chicks (A = autoclaving; B = boiling/extracting). Ross x Ross 1-d-old broiler chicks were fed a corn-soy, phosphorus-deficient diet (22.7% CP, 1% calcium, 0.22% non-phytate phosphorus), with 0, 750, 1,500, 3,000, or 6,000 units of phytase (FTU) to produce bones with a range of ash. The methods were compared with bones from chicks at 7, 14, and 21 d of age. Left legs were used for method B, and right legs were used for method A. Data was analyzed by the general linear models procedure of SAS software, and differences between means were detected using the Duncan's new multiple range test at the 0.05 level. Variance estimates were the mean square errors (from SAS outputs). Sample sizes needed to detect a 2% difference in bone ash were calculated using the method of Zar. The addition of 6,000 FTU/kg increased tibia ash from 26 to 37%, 29 to 41%, and 33 to 43% on Days 7, 14 and 21, respectively (method B). With bones from 7-d-old chicks, the same number of samples was necessary to detect a 2% difference using methods A and B. With bones from 14- and 21-d-old chicks, approximately 50 and 150% more samples were necessary, respectively, using method A. The autoclaving method is less labor-intensive and requires no toxic solvents, but for older birds, many more samples or replications are needed to detect the same treatment differences.
进行了一项实验，以比较两种估算生长中的肉鸡雏鸡骨灰的常用方法（A = 高压灭菌；B = 煮沸/萃取）。罗斯×罗斯1日龄肉鸡雏鸡被饲喂一种玉米-大豆缺磷日粮（22.7%粗蛋白，1%钙，0.22%非植酸磷），添加0、750、1500、3000或6000单位的植酸酶（FTU），以生成具有不同骨灰含量的骨骼。在7、14和21日龄时，将这些方法与雏鸡的骨骼进行比较。左腿用于方法B，右腿用于方法A。数据通过SAS软件的一般线性模型程序进行分析，使用邓肯新复极差检验在0.05水平检测均值之间的差异。方差估计值为均方误差（来自SAS输出）。使用扎尔方法计算检测骨灰2%差异所需的样本量。添加6000 FTU/kg分别使第7、14和21天的胫骨骨灰含量从26%提高到37%、29%提高到41%、33%提高到43%（方法B）。对于7日龄雏鸡的骨骼，使用方法A和B检测2%差异所需的样本数量相同。对于14日龄和21日龄雏鸡的骨骼，使用方法A分别需要大约多50%和150%的样本。高压灭菌法劳动强度较小，且不需要有毒溶剂，但对于年龄较大的鸡，需要更多的样本或重复实验才能检测到相同的处理差异。
