【作者】 王丽娟；

【导师】 单安山；

【作者基本信息】 东北农业大学 ， 动物营养与饲料科学， 2000， 硕士

【摘要】 植物细胞壁中的植酸和纤维素等抗营养的非淀粉多糖能与蛋白质和矿物元素等形成不溶复合物或络和物而降低这些营养物质的利用率。另外，植酸和纤维素还能与动物胃肠道中的消化酶作用降低这些酶的活性，进一步影响饲料养分的消化。 植酸酶，即肌醇六磷酸水解酶，能水解植酸释放出无机磷。纤维素酶能降解细胞壁，从而促进细胞内容物中养分的释放。单胃动物不能分泌植酸酶和纤维素酶等非淀粉多糖酶。一般通过使用外源酶，可以消除植酸和纤维素等的抗营养作用，提高饲料营养物质消化率。国内外已有大量研究分别报道了植酸酶和纤维素酶在动物生产中的应用效果，认为显著提高了植酸磷的和其它养分的生物利用率。但两种酶同时添加的效果未见报道。 本试验旨在通过饲养试验、代谢试验、屠宰试验和分析实验，研究玉米—豆粕型蛋鸡日粮中添加植酸酶和纤维素酶的影响，并探讨影响植酸酶和纤维素酶作用效果的因素以及产蛋鸡对磷的需要量。 在一个长达31周的饲养试验中，选用18周龄海赛克蛋鸡192只，随机分为8组，每组4个重复，每重复6只鸡。试验采用2×2×2正交试验设计（L₈2⁷），两水平非植酸磷（0.38％，0.16％）、两水平植酸酶（300U/kg，0）、两水平纤维素酶（0.1％，0）。基础日粮配方参考鸡的营养需要NRC（1994）。 试验的基本结论如下： 1.对蛋鸡生产性能的影响：添加0.1％纤维素酶可显著降低只日耗料量（P＜0.05）。植酸酶对所观测的生产性能指标影响皆不显著。 2.对蛋鸡营养物质利用的影响：300U/kg植酸酶可显著提高日粮粗灰分、粗蛋白、钙、总磷和铜的表观利用率（P＜0.05）。0.1％纤维素酶显著提高日粮粗纤维（P＜0.05）和钙的表观利用率（P＜0.01）。同时添加植酸酶和纤维素酶对提高植酸酶和铜表观利用率有显著加性效应（P＜0.05）。 3.对蛋鸡血清生化指标的影响：添加300U/kg的植酸酶显著降低了血清磷浓度（P＜0.01），植酸酶（P＜0.01）和纤维素酶（P＜0.01）分别显著提高了碱性磷酸酶的活性。 4.对蛋鸡胫骨质量的影响：添加300U/kg植酸酶显著提高了胫骨折断力（P＜0.05）。添加0.1％纤维素酶显著降低了胫骨灰分绝对重量（P＜0.05）。 5.产蛋鸡对磷的需要量：本试验中，与高磷组（0.38％非植酸磷/nP）相比，低磷组（0.16％nP）蛋鸡并未表现降低的生产性能，而且，显著提高了20周龄蛋壳质量（P＜0.01）和总磷、植酸磷和铜等表观利用率（P＜0.01），但降低了粗蛋白的表观利用率（P＜0.01）。减少对骨骼钙磷的动员，降低血清磷浓度（P＜0.05），显著提高胫骨折断力及胫骨钙和锰含量（P＜0.01），但不利于胫骨磷（P＜0.05）和铜（P＜0.01）的沉积。更多还原

【Abstract】 Phytate and fiber in plant cells have the potential of binding with protein arid minerals such as P and Ca, Cu, Fe, Mt, Zn4 and so on to form insoluble complexes which may reduce the utilization of these nutrients. Furthermore, phytate and fiber may also form complexes with some digestive enzymes in the gastrointestinal tract and decrease the activity of these enzymes with a subsequent decrease in the digestibility of dietary nutrients. Phytase, myo-inositol hexaphosphate phosphohydrolase, is the enzyme that release P from phytate P. Cellulase tend to destroy cell wall to release nutrients. Respective supplementation of phytase or cellulase in the diets of laying hens has been reported to improve the dietary phytate P bioavailability and other nutrients utilization. But the supplemental interactions of the two enzymes have not been reported. The objective of this experiment was to investigate the effects of supplementation of microbial phytase and cellulase and their interactions on layers based on maize and soybean meal diets by a feeding trial, a digesting trial, a slaughtering trial and laboratory experiments. 192 18-week-old Hisex layers were used in a 31-week feeding trial and were randomly arranged to 8 groups with 4 replicates and 6 for each replicate. A 2 X 2 )< 2 factorial arrangement of treatments was used with two levels of nonphytate P(0.38% and 0.16%),two levels phytase (300U/kg and 0) ,two levels cellulase (0.1% and 0) .The diet was formulated as recommended by National Research Council (1994) What can be concluded from the results is as follows: 1. Performance: Addition of 0.1% cdllulase significantly decreased feed intake(P<0.05) No supplemental effect of phytase on performance was found. 2. Utilization of nutrients: 300UIlcg phytase significantly improved the utilization of dietary cmde ash, cnide protein, calcium, total phosphorus and copper (P<0.05) . Addition of 0.1% celhilase increased the utilization of crude fibber (P<0.05) and calcium (P<O.01) 300U/kg phytase and 0.1% cellulase exhibited obvious positive interactions to enhance the utilization of dietary phytic phosphorus and copper (P<0.05) 3. Plasma biochemical parameters: 300U/kg Phytase supplementation decreased plasma P content (P<0.05) . Phytase and cellulase increased plasma ALP activity (P<0.0 I), resective1y. 4. Tibia quality: 300U/kg Supplemental microbial phytase significantly improved tibia breaking strength (P<0. 05) .0.1% cellulase decreased absolute tibia ash weight (P<0.05) 5. Phosphorus requirement of layers compared with higher level P (0.38% nonphos- phorus P/nP) , Lower P (0.16% nP) did not reduce the performance of the layers, but improved 20-week egg shell quality, increased the utilization of dietary total phosphorus, phytic phos- phorus and copper (P<0.0 1), but decreasd the utilization of dietary crude protein, decreased plasma ALP activity (P<0.05), increased tibia breaking strength and calcium, Mn contents (P<0.01) excepting that lowered tibia phosphorus (P<zO.05) and copper (P<0.01) contents. Name:: Wang Lijuan Major: Animal Nutrition Supervisor:: Prof Shari Anshan更多还原