【作者】 刘丹丹；

【导师】 王永军；

【作者基本信息】 西北农林科技大学 ， 动物营养与饲料科学， 2009， 硕士

【摘要】 为评价蚕蛹原料在黄鳝饲料中的应用价值,设计了蚕蛹与鱼粉常规营养和氨基酸含量的比较研究、黄鳝对蚕蛹离体消化率测定、蚕蛹替代鱼粉对黄鳝各组织消化酶活性及黄鳝肉营养品质的影响等4个试验。1.从常规营养成分、氨基酸含量和氨基酸平衡3个方面比较蚕蛹和鱼粉的营养价值。结果表明:蚕蛹干物质含量为91.32%,是鱼粉的1.06倍;以干物质计的粗蛋白、粗脂肪、粗灰分含量为60.58%、27.6%、4.75%,分别是鱼粉的0.86倍、2.19倍和0.28倍;蚕蛹和鱼粉都分别检出18种氨基酸,其总氨基酸含量为49.59%和59.07%;10种必需氨基酸含量分别为24.70%和25.71%,其中蚕蛹中胱氨酸、缬氨酸、异亮氨酸、酪氨酸和色氨酸含量高于鱼粉,蚕蛹10种必需氨基酸含量是鱼粉的96.07%;必需氨基酸占总氨基酸的比例(EAA/TAA)分别为49.81%和43.53%;必需氨基酸与非必需氨基酸的比例(EAA/NEAA)分别为99.27︰100和77.09︰100;蚕蛹必需氨基酸平衡性稍优于鱼粉;研究认为,蚕蛹是一种高蛋白高能量饲料原料,可作为替代鱼粉的一种蛋白原料,同时替代鱼粉配制日粮时应注意补充赖氨酸和矿物质尤其是钙、磷,保证日粮营养的平衡性。2.采用消化道粗酶提取和体外孵育消化的方法,测定了黄鳝和泥鳅对蚕蛹的离体消化率,并以鱼粉为对照,评价2种鱼对蚕蛹的消化利用能力。结果表明:黄鳝对蚕蛹和鱼粉均具有较高的消化率,其中黄鳝对蚕蛹中干物质和粗脂肪的消化率均显著低于鱼粉(P<0.05),对粗蛋白质的消化率极显著高于鱼粉(P<0.01),这使在开发黄鳝人工饲料时用蚕蛹部分或全部替代鱼粉成为可能;泥鳅对蚕蛹和鱼粉均具有一定的的消化率,但各种营养成分的消化率均显著低于鱼粉(P<0.05),所以蚕蛹在泥鳅饲料中不是理想的蛋白源饲料;黄鳝和泥鳅肝胰脏分泌的消化液中的主要消化酶,对各种营养物质的消化发挥着十分重要的作用,其对消化率的影响作用最大。3.采样灌喂添加不同比例蚕蛹的配合饲料的方法,研究蚕蛹对黄鳝胃、前肠、后肠和肝胰脏消化酶活性的影响,包括时间梯度试验和浓度梯度试验2部分。结果表明:蚕蛹对黄鳝各组织蛋白酶活性的影响较大,随蚕蛹添加量的上升,肝胰脏、胃、前肠中蛋白酶活性有升高的趋势,后肠蛋白酶活性有降低的趋势;随时间的延长,各组织的蛋白酶活性有先下降再上升的趋势,后肠蛋白酶活性在灌喂后6h达到峰值,而前肠和胃的峰值分别在1h和6h;与鱼粉比较,蚕蛹组胃、前肠内蛋白酶活性在3h以前低于鱼粉组,6h时高于鱼粉组,表明黄鳝胃对鱼粉蛋白质的消化作用较大,前肠对蚕蛹蛋白质的消化作用较大,这可能与蚕蛹蛋白质的组成与结构有关。蚕蛹对黄鳝各组织脂肪酶和淀粉酶影响较小,无明显的变化规律。4.以蚕蛹为蛋白源等氮替代15%和30%的鱼粉,对平均体重25g的黄鳝,进行4W的饲养试验,并与商品饲料饲喂的网箱养殖黄鳝和野生黄鳝血清生化指标、肌肉品质进行比较,结果表明:随着蚕蛹在饲料中含量的增加,黄鳝生长无显著差异;血清总蛋白、血糖和谷草转氨酶活性显著下降,甘油三酯呈升高趋势;肌肉脂肪含量显著升高,蛋白含量随之下降;试验、网箱和野生黄鳝肌肉中都分别检出17种氨基酸,总氨基酸含量分别为69.70%、66.85%和67.76%,7种必需氨基酸含量分别为42.28%,41.82%和42.54%,鲜味氨基酸含量分别为27.90%,26.42%和26.00%,以FAO模式和鸡蛋蛋白模式对3组黄鳝肌肉必需氨基酸含量进行评定,认为网箱组的必需氨基酸比例最平衡;黄鳝肌肉中检出脂肪酸22种,饱和脂肪酸9种,不饱和脂肪酸13种,高不饱和脂肪酸7种,以网箱组的DHA含量3.97%最高。研究认为,黄鳝饲料中蚕蛹的添加量应控制在30%以下。更多还原

【Abstract】 Four experiments were conducted to evaluate the possibility of silkworm chrysalis (SC) as one kind of feedstuff for Monopterus ablbus commercial feed. In experiment one, level of nutritional ingredients was compared between SC and fish meal (FM). In experiment two, digestibility of SC for Monopterus ablbus was determined in vitro. Influence of dietary SC on digestive enzyme activities, growth performance and flesh quality were studied in experiment three and four respectively.1. Level of nutritional ingredients and amino acids pattern were compared between SC and FM. The results showed that the content of dry matter in SC was 91.32%, 1.06 times as that in FM; Contents of crude protein, crude fat, crude ash were 60.58%, 27.6% and 4.75% in SC (0.86 times, 2.19 times and 0.28 times as those in FM) respectively; A total of 18 kinds of amino acids were determined in both SC and FM. Contents of the total amino acid (TAA) were 49.59% and 59.07% and contents of 10 kinds of essential amino acids (EAA) were 25.71% and 24.70% in SC and FM, respectively. The contents of some amino acids, such as Cys, Val, Ile, Tyr and Trp, were higher in SC than those in FM. EAA/TAA was 49.81% and 43.53%, EAA/NEAA were 99.27% and 77.09 in SC and FM. The balance of amino acid in SC was better than that in FM.2. In vitro digestive ratio of SC by Monopterus ablbus and Misgurnus anguillicaudatus were determined, with FM as the control. The results showed that digestibility of dry matter and crude fat of SC were lower than those of FM. Protein digestibility of SC by Misgurnus anguillicaudatus was significantly lower than that of FM (P<0.05), crud protein digestibility of SC by Misgurnus anguillicaudatus was similar with that of dry matter and crude fat, while Monopterus ablbus had higher digestibility of SC than that of FM (P<0.01). On the other hand, the utilization rate of SC was higher in Monopterus ablbus than that in Misgurnus anguillicaudatus. These results indicated that SC could be used to replace FM partly or totally in Monopterus ablbus feed and with certain limitation in Misgurnus anguillicaudatus feed.3. Digestive enzyme activities in stomach, foregut, hindgut and hepatopancreas of Monopterus ablbus fed different contents of SC were tested. The results showed that protease activities of stomach, foregut and hepatopancreas increased with the increase of SC content in feed. Protease activities of hindgut achieved a peak in 6h after feeding (at 1h and 6h of foregut and stomach, respectively); protease activities of foregut and stomach in SC treatment was lower than that in FM treatment at 3h after feeding, but higher at 6h. Protease activities were higher in stomach and lower in foregut of FM treatment compared with the SC treatment. The difference might be due to the protein profile of SC. The SC had little influence on the activities of lipase and amylase.4. Rice Field Eel with the average weight of 25g were fed for 4 weeks, by using SC as a kind of protein source at the level of 15% and 30%. The biological parameters of serum and flesh quality index were compared among different groups. The results showed that the growth performance in SC groups were not significant different; contents of serum TP, Glu and GOT decreased with the increase of SC content, but TG was in a opposite manner; lipid content of muscle significantly increased but protein content decreased. A total of 17 kinds of amino acids were determined in SC group, cage group and wild group; TAA contents were 69.70%、66.85% and 67.76%; contents of 7 kinds of EAA were 42.28%,41.82% and 42.54%; fresh amino acid were 27.90%,26.42% and 26.00%, respectively. The balance of amino acid of cage group was the best. A total of 22 kinds of fatty acids were determined in muscle, in which 9 kinds of saturated fatty acids, 13 kinds of unsaturated fatty acid, 7 kinds of highly unsaturated fatty acid were found; DHA content was the highest (3.97%) in cage group. It is suggested that the content of SC in Monopterus ablbus feed should be kept lower than 30%.更多还原