Liem A, Pesti G M, Edwards H M
Department of Poultry Science, University of Georgia, Athens 30602-2772, USA.
Poult Sci. 2008 Apr;87(4):689-93. doi: 10.3382/ps.2007-00256.
Supplementation of some organic acids to a P-deficient diet has been shown to improve phytate P utilization. Two experiments were conducted from 0 to 16 d in battery brooders to determine the effect of various organic acids supplementation on phytate P utilization. In both experiments, birds were fed P-deficient corn and soybean meal-based diets. In experiment 1, citric acid, malic acid, fumaric acid, and EDTA were supplemented. Experiment 2 had a 2 x 2 factorial design with 2 sources of Met, 2-hydroxy-4-(methylthio) butanoic acid (HMB) and dl-Met, with or without 500 U/kg of phytase. In experiment 1, the addition of citric, malic, and fumaric acids increased percentage of bone ash, but only the effect of citric acid was significant. The addition of citric and malic acids also significantly increased the retention of P and phytate P (P<0.05). In experiment 2, the addition of phytase to the diet significantly increased 16-d BW gain, feed intake, percentage of bone ash, milligrams of bone ash, phytate P disappearance, and decreased the incidence of P-deficiency rickets. Methionine source did not affect 16-d BW gain, feed intake, feed efficiency, milligrams of bone ash, or P rickets incidence. However, the birds fed HMB had a higher percentage of bone ash and phytate P disappearance compared with the groups fed dl-Met only when phytase was added to the diets. The additions of citric acid and HMB improved phytate P utilization. However, the reason why some organic acids are effective whereas others are not is not apparent.
研究表明，在缺磷日粮中添加某些有机酸可提高植酸磷的利用率。在笼养育雏器中进行了两项从0至16日龄的试验，以确定添加各种有机酸对植酸磷利用率的影响。在两项试验中，均给雏鸡饲喂以缺磷玉米和豆粕为基础的日粮。试验1添加了柠檬酸、苹果酸、富马酸和乙二胺四乙酸。试验2采用2×2析因设计，有2种蛋氨酸来源，即2-羟基-4-(甲硫基)丁酸(HMB)和dl-蛋氨酸，添加或不添加500 U/kg的植酸酶。在试验1中，添加柠檬酸、苹果酸和富马酸可提高骨灰百分比，但只有柠檬酸的效果显著。添加柠檬酸和苹果酸也显著提高了磷和植酸磷的保留率(P<0.05)。在试验2中，日粮中添加植酸酶显著提高了16日龄体重增加、采食量、骨灰百分比、骨灰毫克数、植酸磷消失率，并降低了缺磷佝偻病的发病率。蛋氨酸来源对16日龄体重增加、采食量、饲料效率、骨灰毫克数或磷佝偻病发病率没有影响。然而，只有在日粮中添加植酸酶时，饲喂HMB的雏鸡与仅饲喂dl-蛋氨酸的组相比，骨灰百分比和植酸磷消失率更高。添加柠檬酸和HMB提高了植酸磷的利用率。然而，一些有机酸有效而另一些无效的原因尚不清楚。
