Department of Aquaculture, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, Kafrelsheikh, Egypt.
Genetic and Genetic Engineering, Animal Wealth Development Department, Faculty of Veterinary Medicine, Benha University, Toukh, Egypt.
J Anim Physiol Anim Nutr (Berl). 2024 Jul;108(4):891-908. doi: 10.1111/jpn.13939. Epub 2024 Feb 14.
Phytase is crucial in enhancing the bioavailability and release of phosphorus and other nutrients bound to phytic acid, making them more bioavailable for animal absorption. This study was carried out to inspect the effect of supplementing low phosphorus (P) diet with di-calcium phosphate (DCP) and liquid phytase enzyme (LP), which contains 1500 FTU/kg, on growth performance, intestinal morphometry, proximate body chemical composition, blood profile, immunity status, liver mitochondrial enzyme activities, the expression response and economic returns of Nile tilapia (Oreochromis niloticus). Three triplicate groups of fish (initial weight 5.405 ± 0.045 g, N = 90) were fed on three different diets for 90 days. The first was a control diet with zero DCP; the second was a control diet supplemented with 0.71% DCP; the third was a control diet supplemented with 0.03% LP. The groups were designated as CG, DCP and LP, respectively. Results showed that LP induced considerable improvements (p < 0.05) in FBW, body weight gain, weight gain rate, specific growth rate, HIS, viscero-somatic index, spleen-somatic index, feed conversion ratio, blood parameters and the histomorphometry assessment of intestinal villi absorptive capacity, compared with the other groups. Also, whole-body protein and lipid contents pointedly (p < 0.05) increased by LP, compared with the DCP group. A positive response (p < 0.05) to the phytase enzyme was noted in complexes I, III and IV of the mitochondrial liver complex enzyme activity. Likewise, the relative gene expression levels of (GHr-1, IGF-1, FAS and LPL) were notably (p < 0.05) upregulated by phytase enzyme, associated with DCP and control groups. Further, phytase recorded the highest total return and profit percentage. It can be concluded that Nile tilapia benefits from using phytase enzyme 1500 FTU/kg at 0.03% without adding DCP in terms of good performance and profits.
植酸酶在提高与植酸结合的磷和其他营养素的生物利用度和释放方面至关重要，使其更有利于动物吸收。本研究旨在研究在低磷（P）日粮中添加磷酸二钙（DCP）和液体植酸酶（LP）对生长性能、肠道形态、体成分、血液参数、免疫状态、肝线粒体酶活性、尼罗罗非鱼（Oreochromis niloticus）的表达反应和经济效益的影响。三组三重复的鱼（初始体重 5.405±0.045g，N=90）分别用三种不同的日粮喂养 90 天。第一组是无 DCP 的对照日粮；第二组是添加 0.71% DCP 的对照日粮；第三组是添加 0.03% LP 的对照日粮。分别命名为 CG、DCP 和 LP。结果表明，与其他组相比，LP 诱导了相当大的改善（p<0.05），表现在 FBW、体重增加、增重率、特定生长率、HIS、内脏体比、脾体比、饲料转化率、血液参数和肠道绒毛吸收能力的组织形态学评估方面。此外，与 DCP 组相比，LP 组的全鱼体蛋白质和脂质含量明显（p<0.05）增加。肝脏线粒体复合酶活性复合体 I、III 和 IV 中观察到对植酸酶的正响应（p<0.05）。同样，植酸酶显著（p<0.05）上调了 GHr-1、IGF-1、FAS 和 LPL 基因的相对表达水平，与 DCP 和对照组相比。此外，植酸酶记录了最高的总回报和利润率。可以得出结论，尼罗罗非鱼在不添加 DCP 的情况下，使用 1500FTU/kg 的植酸酶 0.03%可以获得良好的性能和利润。
