粉碎与制粒对肉鸡养分利用率的影响

分别选择10日龄和30日龄AA肉仔鸡各144只,均随机分成8个处理,每个处理6个重复,每个重复3只鸡。采用粉料和颗粒2种料型,每个料型4个粉碎粒度梯度(378、430、516、590μm),利用传统全收粪法,研究制粒与粉碎粒度对养分利用率的影响。结果表明:肉鸡18~21日龄时,粉料的养分和能量利用率高于颗粒饲料,饲喂粉料时,养分利用率随粉碎粒度的增大而线性增大(P0.05),饲喂颗粒料时,养分利用率随粉碎粒度的增大反而线性降低(P0.05)。2种料型对粒度变化出现了相反的效应。肉鸡38~41日龄时,颗粒饲料养分和能量的利用率高于粉料,不同粉碎粒度不再影响肉大鸡日粮的养分利用率(P0.05)。结论:料型和肉鸡日龄会影响原料粉碎粒度对养分利用率的作用。     

复合酶制剂对生长猪的生产性能和养分消化性的影响

选择３５ｄ龄断奶体重约９ｋｇ的长大二元杂交仔猪２４头,随机分成２组,研究添加复合酶制剂以生长猪生产性能的影响。选择体重３５￣４０ｋｇ６头阉公猪采用全收粪法进行消化试验,研究复合酶制剂对日粮养分表现消化率的影响。结果表明,添加酶制剂能显著提高生长猪地生产性能和日粮养分的表现消化率,与对照组组相比,日增重提高８．２９（Ｐ〈０．０５）。饲料转化率提高８．８９％（Ｐ〈０．０５）,粗纤维表现消化率提高３６．     

豆粕粉碎粒度对肉鸡颗粒饲料质量及养分利用率的影响

选用直径1.5、2.0、2.5mm的3种规格的筛片对豆粕进行粉碎,得到豆粕的质量几何平均粒度分别为505.34、637.32、716.80μm,然后制成肉鸡颗粒料,比较颗粒料间的质量,分析粉碎和制粒过程中生产效率和单位产量电耗,并且进行代谢试验研究粒度对营养利用率的影响.试验结果表明:选用1.5mm直径筛片粉碎豆粕生产的颗粒料硬度和稳定度(PDI)均高于(P＜0.05)2.0mm和2.5mm直径组,但含粉率没有差异(P＞0.05).1.5mm筛片进行粉碎豆粕的单位产量电耗明显高于2,0mm和2.5mm直径组(P＜0.05),但制粒的单位产量电耗2.5mm组最低,2.0mm筛片组综合生产成本最低.1.5mm和2.0mm筛片组CP的代谢率显著高于2.5mm筛片组(P＜0.05).豆粕粉碎粒度对肉鸡的OM、DM、GE代谢率和代谢能(ME)均没有影响(P＞0.05).孔径为2.0mm的筛片为生产粒径为3.2mm的肉鸡颗粒料的最佳筛片筛孔孔径.     

日粮中添加乳化剂对肉鸡生长性能、屠宰性能和养分表观利用率的影响

研究在肉鸡米糠油日粮中添加500mg/t乳化剂对肉鸡生产性能、屠宰性能及养分表观利用率的影响。采用单因子完全随机分组试验设计,将288只1日龄AA肉鸡随机分为4组,每组6个重复,每个重复12只鸡。结果表明:添加乳化剂提高了肉鸡1~21d和1~42d的体重(P0.05),降低了料肉比(P0.05);提高了肉鸡前期干物质(P0.01)、能量(P0.01)、粗蛋白质(P0.01)的表观利用率;也提高了肉鸡后期干物质(P0.05)、能量(P0.01)、粗脂肪(P0.05)粗蛋白质(P0.01)的表观利用率。乳化剂的添加对肉鸡屠宰性能没有显著影响。     

复合酶制剂对安格斯肉牛生产性能及养分消化率的影响

研究复合酶制剂对安格斯肉牛生产性能和养分消化率的影响,为外源复合酶制剂在肉牛饲养中的应用提供理论依据。选取24头初始体重为(236±22.51)kg的健康安格斯肉牛,随机分成4个处理组,即对照组、试验Ⅰ组、试验Ⅱ组、试验Ⅲ组,每组6只牛。对照组不添加复合酶制剂,试验组在补充精料中分别添加3种相同剂量的不同品牌复合酶制剂。结果表明,补充精料中添加复合酶制剂可以显著提高安格斯肉牛的平均日增重(P0.05),试验Ⅲ组效果最好,比对照组提高7.49%。试验Ⅰ、试验Ⅱ、试验Ⅲ组的粗蛋白质、NDF、ADF的表观消化率显著高于对照组(P0.05)。试验组中粗脂肪的表观消化率较对照组无显著差异(P0.05)。     

日粮添加木聚糖酶对肉仔鸡表观消化率及肠道组织形态的影响

通过在小麦基础日粮中添加木聚糖酶,研究了木聚糖酶对肉仔鸡回肠及总消化道养分和非淀粉多糖(NSP)表观消化率及小肠形态的影响.试验将7日龄肉仔鸡随机分为3组,即为小麦基础日粮中添加0%、0.03%和0.1%的加酶组,饲喂至21日龄.结果表明:与对照组相比,0.1%的加酶组显著提高了淀粉在回肠和总消化道中的表观消化率(P<0.05),极显著提高了可溶性非淀粉多糖(SNSP)、不溶性非淀粉多糖(INSP)在回肠的表观消化率(P<0.01),显著提高了SNSP的总消化道表观消化率(P<0.05).此外,0.1%的加酶组还极显著降低了十二指肠的肠壁厚(P<0.01),并极显著增加了肉仔鸡回肠隐窝深度和绒毛高度(P相似文献   

包被肉桂油对肉鸡生长性能、血浆生化指标、免疫器官指数和肠道形态结构的影响

研究旨在探讨日粮中添加不同水平的包被肉桂油对肉鸡生长性能、血浆生化指标、免疫器官指数和肠道形态结构的影响,试验选取1日龄(45.23±0.50)g的科宝(cobb)肉鸡540只,随机分为6个处理组:对照组、正对照组、50mg/kg肉桂油组、100mg/kg肉桂油组、200mg/kg肉桂油组、300mg/kg肉桂油组;每组6个重复,每个重复15只鸡。试验期为42d。结果表明:1)与对照组相比,日粮中添加300mg/kg肉桂油提高了42日龄肉鸡的平均日增重、平均日采食量(P0.05)。2)日粮中添加不同浓度的肉桂油均降低了肉鸡前期血液中谷丙转氨酶(ALT)活力、谷草转氨酶(AST)活力(P0.05)。3)日粮中添加50、100 mg/kg的包被肉桂油分别提高了21、42日龄脾脏指数(P0.05)。4)日粮中添加300mg/kg肉桂油提高了肉鸡前期十二指肠的绒毛高度、空肠绒毛高度/隐窝深度(P0.05)。综合来看,日粮中添加肉桂油能够提高肉鸡的生长性能,促进脾脏发育,改善血液状况、保持肠道形态结构完整性。包被肉桂油可以替代黄霉素在肉鸡饲料中的应用,适宜添加剂量为300mg/kg。     

NSP酶制剂对肉仔鸡生产性能和养分利用率的影响

选用1日龄罗斯308肉仔鸡256只,随机分为4个组:1组饲喂玉米-豆粕型日粮.2组饲喂在1组日粮基础上降低代谢能0.21 MJ/kg的日粮,3组饲喂"2组日粮+200 g/t酶制剂",4组饲喂"2组日粮+400 g/t酶制剂",研究NSP酶制剂对肉仔鸡生产性能和养分代谢的影响.结果表明:3、4组平均日增重、料重比均不同程度的优于2组;3、4组在42日龄时能量、干物质和粗蛋白质等养分代谢率也提高;4组的表观代谢能比2、1组分别提高了2.23%(P<0.05)和0.98%(P>0.05),真代谢能与2、1组相比分别提高了2.06%(P<0.05)和0.89%(P>0.05);3、4组的营养物质代谢率与2、1组相比有1.5%～8.5%(P<0.05)的改善幅度.     

复合酶制剂对绿茶面包品质的影响分析

以绿茶面包为研究对象,分别探讨α-淀粉酶、脂肪酶、半纤维素酶对其感官评分和硬度的影响,以硬度为响应值,通过响应面分析法确定复合酶制剂的最佳组合。结果表明,与对照组相比,单一酶制剂均能改善面包的口感和硬度,延缓面包老化的程度。复配后, 3种酶制剂的最佳组合为:α-淀粉酶添加量0.105 g/kg、脂肪酶添加量0.103 g/kg、半纤维素酶添加量0.607 g/kg。与单一酶制剂相比,复合酶制剂在硬度、感官评分和抗老化方面具有一定优势,能明显改良绿茶面包品质。     

日粮中添加乳化剂对肉鸡脂肪代谢的影响

研究在猪油日粮中添加500g/t乳化对内鸡生产性能、养分表观利用率及胴体品质的影响.结果表明:添加乳化剂提高了肉鸡前期、后期及全期的平均日增重(P>0.05),降低了料重比(P>0.05),提高了肉鸡前期粗蛋白质(P<0.01)、能量(P<0.05)的表现利用率;乳化剂能降低42日龄肉鸡肌间脂肪宽度(P<0.05)和皮下脂肪厚度(P<0.01),提高胸肌和腿肌重(P<0.05);乳化剂也使21日龄肉鸡腹脂重明显降低(P<0.05).     

Functionality of enzymes that hydrolyse starch and non-starch polysaccharide in breadmaking

 Nine commercial enzyme preparations and two laboratory-designed mixes with amylase and/or pentosanase/xylanase activity were used to prepare bread samples, and the effects on bread quality and keeping properties were determined. With the doses added, enzymes significantly shortened fermentation time without affecting the pH or the machinability of the doughs. Bread with an improved volume, a greater intensity of aroma and a softer texture was obtained. Loaves had a less intense and characteristic taste and, in some cases, an uneven grain. All enzymes delayed bread firming, but rates varied with each preparation. Factor analysis classified bread samples according to their composition and source. Received:7 November 1996/Revised version: 21 January 1997     

Functionality of enzymes that hydrolyse starch and non-starch polysaccharide in breadmaking

 Nine commercial enzyme preparations and two laboratory-designed mixes with amylase and/or pentosanase/xylanase activity were used to prepare bread samples, and the effects on bread quality and keeping properties were determined. With the doses added, enzymes significantly shortened fermentation time without affecting the pH or the machinability of the doughs. Bread with an improved volume, a greater intensity of aroma and a softer texture was obtained. Loaves had a less intense and characteristic taste and, in some cases, an uneven grain. All enzymes delayed bread firming, but rates varied with each preparation. Factor analysis classified bread samples according to their composition and source. Received:7 November 1996/Revised version: 21 January 1997     

Characterisation of fermentation of high-gravity maize mashes with the application of pullulanase,proteolytic enzymes and enzymes degrading non-starch polysaccharides

The aim of the research was to assess the possibility of the fermentation productivity rising through the increase in corn mashes extract from 16–17 to 20–21°Balling, yet keeping a 3-day fermentation period. The second goal was to obtain the highest possible utilization of starch in the raw material through deep enzymatic degradation and utilization of available sugars and simultaneous maintenance of high quality spirit. It was found that fulfilling the above during the 3-day fermentation period was possible with the application of pullulanase as an additional amylolytic enzyme. Adding pullulanase resulted in the acceleration of the starch hydrolysis degree, which led to lower amounts of unhydrolyzed dextrins and higher ethanol yield. When the supportive enzymes complex (pullulanase, protease and cellulase) was used, the final ethanol concentration reached 10.86 ± 0.04% v/v, with ethanol yield at 68.41 ± 0.23 dm³ of absolute ethanol (A₁₀₀) per 100 kg of starch, which was 95.25 ± 0.32% at the theoretical value. The acceleration of starch enzymatic degradation and the application of a proteolytic preparation visibly shortened both initial and main fermentation phases. This in turn increased the time of the final fermentation phase and resulted in more extensive utilization of substrates by yeasts with simultaneous reduction of the final concentration of acetaldehyde (26.0 ± 0.5 mg/dm³A₁₀₀) and diethyl acetal of acetaldehyde (2.5 ± 0.5 mg/dm³A₁₀₀). The quality of spirit obtained was positively verified also in terms of relatively low concentration of higher alcohol (3912.2 ± 9.8 mg/dm³A₁₀₀). Preliminary analysis of costs (without raw-material) of 1 l distillate production indicated the possibility to reduce the costs by 18–20%.     

Effects of source of protein and carbohydrate on ruminal fermentation and passage of nutrients to the small intestine of lactating cows

Four early lactation multiparous Holstein cows were used in a 4 x 4 Latin square to investigate the effects of source of protein (fish meal or soybean meal) and carbohydrate (corn or barley) on ruminal fermentation, flow of nutrients to the small intestine, and animal performance. The treatments, arranged in a 2 x 2 (protein x carbohydrate) factorial were: 1) corn plus soybean meal; 2) corn plus fish meal; 3) barley plus soybean meal; and 4) barley plus fish meal. Dry matter and starch intakes were greater when corn was fed than when barley was fed. Barley-based diets were more extensively degraded in the rumen than corn-based diets and therefore provided more energy for microbial growth. However, passage of amino acids and starch to the duodenum was greater for corn-based diets than barley-based diets, because of the greater intake and lower ruminal degradability of the corn-based diets. Microbial protein constituted a larger portion of the total N and had a greater influence on the pattern and quantity of amino acids that passed to the duodenum than did protein from fish meal or soybean meal, which escaped ruminal degradation. Feeding corn-based diets increased production of milk and milk protein compared with feeding barley-based diets.     

Effects of source and amount of protein on ruminal fermentation and passage of nutrients to the small intestine of lactating cows

Four Holstein cows fitted with ruminal and duodenal cannulas were used in a 4 x 4 Latin square to investigate the effects of source (corn gluten meal or soybean meal) and amount (14.5 or 11.0%) of CP on ruminal fermentation, passage of nutrients to the small intestine, and animal performance. Cows wee fed for ad libitum intake a diet of 60% corn silage and 40% concentrate on a DM basis. The treatments, arranged in a 2 x 2 (source x amount of CP) factorial, were 1) 14.5% CP, soybean meal; 2) 11.0% CP, soybean meal; 3) 14.5% CP, corn gluten meal; and 4) 11.0% CP, corn gluten meal. Digestion in the rumen of OM, starch, ADF, and NDF was not affected by source or amount of CP in the diet. Total VFA and NH3 concentrations in ruminal fluid were increased by feeding diets that contained 14.5% CP or soybean meal. FLows of non-NH3 N and amino acids to the duodenum were greater in cows fed the 14.5% CP diets because of a greater flow of non-NH3 nonmicrobial N to the duodenum. Larger amounts of lysine passed to the duodenum when cows were fed soybean meal compared with corn gluten meal. Microbial N flow to the duodenum and efficiency of microbial growth were not affected by treatments, suggesting that ruminal NH3 concentration was not limiting for maximal microbial protein synthesis. Feeding 14.5% CP diets increased the production of milk (29.5 vs. 26.8 kg/d) and milk protein compared with 11.0% CP diets, possibly because of greater passage of amino acids to the small intestine. Feeding soybean meal to cows increased production of milk protein compared with feeding corn gluten meal, possibly because more lysine passed to the small intestine.     

Hull-less barley for swine: ileal and faecal digestibility of proximate nutrients,amino acids and non-starch polysaccharides

The nutritive value of three hull-less barley cultivars (Condor, Falcon and CDC Buck) were evaluated. The samples were analysed for proximate composition, amino acids and non-starch polysaccharides (NSP). Wheat and normal barley were used for comparison. Apparent digestibilities were determined with eight cannulated pigs. The diets were formulated to have all energy and protein supplied by the cereals. Compared to normal barley, hull-less barley has higher contents of protein and amino-acids, and lower levels of fibre components. The levels of several essential amino acids in hull-less barley are higher than in wheat. No obvious differences in NSP composition were observed, but the hull-less barley contained considerably higher levels of β-glucan compared to hulled barley and wheat. In digestion trials the piglets did not accept the diet in which conventional barley was formulated as the only energy and protein source, whereas hull-less barleys were well consumed. The results showed that, in the order of Condor, Falcon, CDC Buck and wheat, the overall tract digestibilities of intake energy were 83·1, 80·3, 83·2 and 82·9%, and of protein were 72·6, 69·5, 76·5 and 77·6%, respectively. The averages of apparent ileal amino acid digestibility were 56·5, 58·4, 65·3 and 65·4%, respectively. Hull-less barleys showed 20–37% ileal digestibility of total NSP. This study provides digestibility coefficients of hull-less barleys, and it is concluded that the digestibility of hull-less barley is comparable to wheat and superior to hulled barley in terms of nutrient composition and acceptability. © 1998 SCI.     

Vesicular transport of nutrients in the small intestine during natural feeding

Ultrastructural aspects of the absorption of nutrients by the rat small bowel under natural feeding and administration of a food mixture homogenate to a small bowel strip were studied. It is shown that as early as 25 min after the onset of feeding, nutrients get into the proximal part of the small bowel, run across the epithelial barrier and enter the stroma of the intestinal villi and the vascular bed. Active absorption of nutrients is also observed in situ under limited intracavitary hydrolysis. The identified nutrients penetrate the apical membrane of enterocytes by pinocytosis, are detectable but inside vesicular structures of the cell, and get into the intercellular space by exocytosis. The concept of the existence of the control systems preventing foreign substances from penetration in the body and eliminating the sequels of such a penetration has been worded.     

麦麸非淀粉多糖对烘焙品质的影响

综述麦麸中非淀粉多糖类成分对烘焙产品的影响。主要介绍麦麸中两种重要的非淀粉多糖(阿拉伯木聚糖和β-葡聚糖)的分子结构、理化性质和生理功能,并在比较其加工性能的基础上,分析其对面团流变特性、烘焙产品营养/感官品质以及储藏特性等方面的影响,最后对相关作用机理进行分析。     

Laboratory performance on analysis of mandatory nutrients and preparation of nutrition labelling

This study assessed the performance of 17 laboratories in Thailand in analysing mandatory nutrients in salted, fried broad bean and in using data to prepare nutrition labels. Nutrient levels in the test material, as robust mean (x^∗) and robust standard deviation (s^∗), were assigned in line with ISO 13528. Data obtained from the laboratories were statistically evaluated against these values. Laboratories with satisfactory, questionable and unsatisfactory results for each nutrient were identified based on robust z-score. Laboratories achieving satisfactory analytical results (z-score ? 2) were for lipid, 82%; protein, 85%; Na, 82%; Ca, 62%; Fe, 81%; ash, 70%; and moisture, 62%. Reference values for some nutrients in broad bean powder were developed using data from satisfactorily performing laboratories. Less than 20% of the laboratories demonstrated good performance in preparing nutrition labels. Common mistakes were the nutrition information format, estimation of serving size and serving(s) per package.