Ajith Sreeja, Shet Divya, Ghosh Jyotirmoy, Awachat Vaibhav B, Bhat Karthik, Pal Dintaran, Elangovan Arumbackam V
ICAR-National Institute of Animal Nutrition and Physiology, Bengaluru, Karnataka, India.
Department of Microbiology, Jain University Bengaluru, Karnataka, India.
Vet World. 2018 Jun;11(6):758-764. doi: 10.14202/vetworld.2018.758-764. Epub 2018 Jun 7.
The aim of this study was to investigate the effects of phytase which was laboratory produced by on the growth performance, mineral retention, and bone traits of broilers fed with low dietary calcium and phosphorus.
The extracellular phytase enzyme secreted into the crude filtrate was concentrated by ammonium sulfate precipitation to obtain an activity of 500 phytase units (FTU). A total of 90 1-day-old chicks (Cobb 500) were randomly divided into three treatment groups with five replicates having six birds each. Dietary treatment, T1, was with 0.45% non-phytate P (NPP) during starter and 0.40% during finisher phase with 1% Ca. Dietary treatment, T2, had 0.37% NPP during starter and 0.32% in finisher phase with 1% Ca and supplemental lab phytase at 500 FTU/kg. Dietary treatment, T3, was similar to T2 with a lower Ca of 0.8%.
There was no significant difference among the dietary treatments with regard to body weight gain, feed intake, feed conversion ratio, and Ca retention (p>0.05). However, a significant improvement in retention of P by birds was observed in phytase supplemental groups T2 and T3 (p<0.05). Dry weight of tibia (2.58-2.78 g/kg live weight) and ash content (39.7-41.8%) was comparable among treatments. A similar trend was observed for bone Ca, P, and Mn content.
The study indicated that 500 FTU/kg phytase can be effectively supplemented in a broiler diet with low phosphorus (0.37% in starter and 0.32% NPP in finisher diet) and low calcium (0.8% in diet) for better growth performance and with successful replacement of dietary P by 0.08 % and reduced P excretion into the environment in broiler chicken.
本研究旨在调查实验室生产的植酸酶对饲喂低钙磷日粮的肉鸡生长性能、矿物质保留率和骨骼特性的影响。
通过硫酸铵沉淀法浓缩粗滤液中分泌的胞外植酸酶，使其活性达到500植酸酶单位（FTU）。总共90只1日龄雏鸡（科宝500）随机分为三个处理组，每组五个重复，每个重复六只鸡。日粮处理T1，在育雏期非植酸磷（NPP）含量为0.45%，育肥期为0.40%，钙含量为1%。日粮处理T2，育雏期NPP含量为0.37%，育肥期为0.32%，钙含量为1%，并添加500 FTU/kg的实验室生产的植酸酶。日粮处理T3与T2相似，但钙含量较低，为0.8%。
在体重增加、采食量、饲料转化率和钙保留率方面，各日粮处理之间无显著差异（p>0.05）。然而，在添加植酸酶的T2和T3组中，观察到鸡对磷的保留率有显著提高（p<0.05）。各处理组胫骨干重（2.58 - 2.78 g/kg活体重）和灰分含量（39.7 - 41.8%）相当。骨骼钙、磷和锰含量也呈现类似趋势。
该研究表明，在低磷（育雏期0.37%，育肥期日粮0.32% NPP）和低钙（日粮0.8%）的肉鸡日粮中有效添加500 FTU/kg植酸酶，可提高生长性能，成功替代日粮中0.08%的磷，并减少肉鸡向环境中的磷排泄。
