首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 812 毫秒
1.
本文采用去盲肠和有盲肠公鸡的对比试验方法研究了盲肠对饲料磷的消化作用。结果表明：（１）去盲肠鸡内源磷排泄量为４９ｍｇ／日．只,有盲肠鸡的内源磷排泄量为４２ｍｇ／日．只,两者差异极显著（Ｐ〈０．０１）,可见,盲肠能够消化吸收内源磷;（２）当公鸡采食含豆粕、棉仁粕、菜籽粕、花生粕或胡麻粕的半纯合日粮时,植酸磷采食量较高,有盲肠鸡磷的排泄量显著低于去盲肠鸡,真消化率显著高于去盲肠鸡（Ｐ〈０．０５）,表明  相似文献   

2.
分别用２４只去盲肠和未去盲肠健康公鸡，测定了豆粕、棉仁粕和菜籽粕的氨基酸消化率。试验结果表明：去盲肠鸡内源氨基酸排泄量显著高于未去盲肠鸡（Ｐ＜０．０５）；在大豆粕中，胱氨酸、苏氨酸等５种氨基酸的消化率未去盲肠鸡显著高于去盲肠鸡（Ｐ＜０．０５）；在棉仁粕和菜籽粕中，除个别氨基酸外，大多数氨基酸及氨基酸总和的消化率未去盲肠鸡显著高于去盲肠鸡（Ｐ＜０．０５），可见，饲料种类、试鸡有无盲肠均影响饲料ＡＡＡＤ和ＴＡＡＤ。盲肠微生物对内源及饲料中未消化蛋白质、多肽及氨基酸具有分解作用，干扰饲料ＡＡＡＤ和ＴＡＡＤ测定。对于不易消化，氨基酸含量相对不平衡的低品质蛋白质饲料干扰尤其严重。因此用去盲肠公鸡测定的饲料ＡＡＤ值更接近氨基酸在消化道内消化吸收的真实情况。  相似文献   

3.
1. Maize, wheat and barley meals, and a protein-free diet were each force-fed to 24 intact and 24 caecectomised adult cockerels. For each test, birds were starved of solid food for 48 h, fed, and then excreta collected for 48 h. 2. Quantities of nitrogen (N) and amino acids excreted after feeding the protein-free diet did not differ between intact and caecectomised birds. 3. True digestibility coefficients of N and amino acids did not differ between intact and caecectomised birds. 4. Differences between cereals in apparent digestibility of amino acids were inconsistent and more readily attributed to differences between amino acid intake than bioavailability. 5. Differences between cereals in true digestibility of amino acids were confined to higher values for N, aspartic acid, alanine and leucine in maize than in barley or wheat meals.  相似文献   

4.
分别用２４只去盲肠和未去盲肠健康公鸡，测定了花生粕、胡麻粕和芝麻粕的氨基酸消化率。结果表明：去盲肠鸡内源氨基酸排泄量显著高于未去盲肠鸡（Ｐ＜０．０５）；在花生粕中，胱氨酸、赖氨酸、天冬氨酸和谷氨酸的ＡＡＤ未去盲肠鸡显著高于去盲肠鸡（Ｐ＜０．０５）；在胡麻粕和芝麻粕中，除酪氨酸和脯氨酸外，其它各种氨基酸及１６种氨基酸总和的ＡＡＡＤ和ＴＡＡＤ未去盲肠鸡显著高于去盲肠鸡（Ｐ＜０．０５）。鸡盲肠微生物对内源及饲料中未消化蛋白质、多肽及氨基酸具有分解作用，干扰饲料ＡＡＡＤ和ＴＡＡＤ测定。对于不易消化、氨基酸含量相对不平衡的低品质蛋白质饲料干扰尤其严重。在测定的３种饼粕中，花生粕氨基酸消化率最高，胡麻粕次之。过度热处理的芝麻粕氨基酸平均消化率为４７．３％，赖氨酸消化率为２１．７％。  相似文献   

5.
1. Three isonitrogenous diets were formulated in which soyabean (dehulled), sunflower (hulled) and groundnut (dehulled) meals were the sole protein sources. 2. 50 g of each diet was tube-fed to each of 24 intact and 24 caecectomised cockerels, which had been previously starved for 48 h. Excreta were collected, individually, for 48 h. The concentrations of amino acids in the diets and excreta were determined, and digestibility coefficients calculated. 3. Differences between intact and caecectomised birds for true digestibility evaluations reached significance for threonine, glycine and lysine only. Deamination of threonine and glycine, and synthesis of lysine, in the caeca was implied. 4. Neither the true digestibility of nitrogen, nor that of the sum of the amino acids differed between protein sources. 5. True digestibilities of most essential amino acids, considered individually, in sunflower and groundnut meals were similar to or greater than, those of soyabean meal. Exceptionally, lysine was more digestible in soyabean (0.879) than in sunflower (0.722) or groundnut (0.788) meals.  相似文献   

6.
1. Three subsamples of a batch of meat and bone meal (MBM0) were heated at 150 degrees C for 1.5 h (MBM1.5), 3 h (MBM3) or 5 h (MBM5). 2. The MBM's were included in 4 wheat-gluten based diets, each limiting in lysine. 3. The lysine digestibility for each of the diets was determined using precision-fed intact adult cockerels and caecectomised adult cockerels, ileal cannulated adult cockerels, the ileal digesta and excreta of young growing chickens. 4. The results of the digestibility assays were compared with the relative amount of lysine available as determined by growth assay. 5. Comparison of the regression lines of digestible lysine (determined with the digestibility assays) on available lysine (determined by growth assay) indicated that while the magnitude of the digestibility values varied significantly (P less than 0.05) depending on the type of assay used, the differences in lysine digestibility as a result of heat treatment across the 4 diets was the same when comparing assays (the regression lines were parallel). 6. The results of each digestibility assay also correlated with relative digestibility values determined by growth.  相似文献   

7.
Meat-and-bone meal (MBM), which had been heated (150 degrees C) for 0, 1.5, 3 or 5 h, was used along with an indigestible marker in four diets which were fed to young growing chickens and adult cockerels fitted with ileal cannulae. The ileal digesta from each group of birds were sampled and the apparent amino acid digestibilities of the four diets containing MBM were determined. The apparent digestibility values from growing chickens were higher (P less than 0.05) than those from cannulated cockerels. Differences in apparent digestibility of amino acids between diets as a result of heat treatment were consistent for all amino acids when comparing both techniques, with the exception of glutamic acid and arginine.  相似文献   

8.
This study evaluated the effect of two rendering processes applied to meat and bone meal (MBM) production, associated or not with extrusion, by measuring diet apparent total tract digestibility of dogs and cats, and true digestibility of amino acids (AA) by cecectomized roosters. Four diets were evaluated, with the main protein source as follows: conventional and extruded MBM; high temperature and pressure (HPT; 135 °C, 3 bar, 20 min) and extruded MBM; conventional non‐extruded MBM; HPT non‐extruded MBM. Nutrient digestibility and food metabolizable energy content were evaluated with dogs and cats by the method of total collection of faeces. True AA digestibility was evaluated by a precision‐fed assay with cecectomized roosters. The evaluated MBM had high‐ash content. The HPT process of MBM increased the digestibility of crude protein of the diets by cats, and the true digestibility of several AA by cecectomized roosters. The extrusion process did not modify the apparent total tract nutrient digestibility of MBM by dogs and their amino acid digestibility by roosters, but increased the digestibility of the dietary protein by cats. Dogs fed HPT MBM presented a higher urea post‐prandial response, suggesting reductions in bioavailability and protein synthesis from absorbed AA.  相似文献   

9.
试验旨在测定大米粉氨基酸消化率的同时,探讨去盲肠与正常黄羽肉鸡对大米粉氨基酸消化率的影响。结果表明:大米粉中氨基酸表观消化率去盲肠鸡普遍高于正常鸡,丙氨酸、亮氨酸和赖氨酸差异显著(P<0.05);大米粉中氨基酸的真消化率亦普遍表现为去盲肠鸡高于正常鸡,丙氨酸差异显著(P<0.05),酪氨酸差异极显著(P<0.01)。大米粉的总氨基酸表观消化率和真消化率在两种试鸡间差异不显著(P>0.05)。去盲肠鸡的内源氨基酸排泄量大多数测值高于正常鸡,但差异不显著(P>0.05)。本试验建议用正常鸡的测定值表示黄羽肉鸡对大米粉的氨基酸消化率。  相似文献   

10.
试验选用64羽平均体重为(3.73±0.10)kg健康爱拔益加成年肉公鸡,测定了赖氨酸硫酸盐和赖氨酸盐酸盐的赖氨酸消化率。将试验鸡随机分为4个处理,每个处理4个重复,每个重复4羽。处理1为绝食组;处理2为酪蛋白组;处理3为酪蛋白日粮添加赖氨酸硫酸盐组;处理4为酪蛋白日粮添加赖氨酸盐酸盐组。分别采用酪蛋白法和绝食法测定氨基酸的内源损失。结果表明:①利用酪蛋白法和绝食法测定的内源损失差异不显著(P>0.05);②赖氨酸硫酸盐的赖氨酸表观消化率为87.75%,利用酪蛋白法和绝食法测得的真消化率分别为99.34%和98.64%;③赖氨酸盐酸盐的赖氨酸表观消化率为87.81%,利用酪蛋白法和绝食法测得的真消化率分别为99.37%和98.67%。综上可得,采用酪蛋白法和绝食法测定的氨基酸内源损失无显著性差异;赖氨酸硫酸盐与赖氨酸盐酸盐的赖氨酸消化率差异不显著。  相似文献   

11.
1. Experiments were conducted to assess the influence of caecectomy on amino acid availability (AAA) of three feedstuffs for goose. 2. Nine caecectomised and 9 intact Yangzhou ganders, 24 weeks old, were used in these experiments. Fish meal, soybean meal and cottonseed meal were used as the sole source of protein. The endogenous amino acid (AA) losses were evaluated by a nitrogen (N)-free diet method. The influence of caecectomy on apparent amino acid availability (AAAA) in fish meal, soybean meal and cottonseed meal was assessed in experiment 1 and true amino acid availability (TAAA) of three protein diets was determined in experiment 2. 3. Results showed that, in the soybean meal and cottonseed meal, the AAAA and TAAA of most AA determined by the intact ganders were higher than in the caecectomised ganders; in the fish meal, the AAAA and TAAA of most AA determined by the intact ganders were lower than in the caecectomised ganders. 4. Results of the present study suggest that the effect of caecectomy on AAA in geese was dependent on the feedstuff assayed, and it was better to use caecectomised poultry for AAA assessment.  相似文献   

12.
1. The apparent ileal and excreta digestibilities of amino acids in 15 samples representing 12 food ingredients were determined using 5-week-old male broiler chickens. The ingredients included 3 samples of cereals (wheat, maize and sorghum), 6 samples of plant protein meals (soyabean meal, cottonseed meal, canola meal and sunflower meal) and 6 samples of animal protein meals (meat meal, meat-and-bone meal, feather meal and fish meal). 2. The test ingredients were incorporated as the sole source of dietary protein in assay diets. Each diet was offered ad libitum to 3 pens (4 birds/pen) from d 35 to d 42 post-hatching. Total collection of excreta was carried out during the last 4 d. All birds were killed on d 42 and the contents of the lower half of the ileum were collected. Apparent ileal and excreta amino acid digestibilities were calculated using acid-insoluble ash as the indigestible marker. 3. The influence of site of measurement was found to vary among food ingredients, among samples within an ingredient and among different amino acids within an ingredient. Ileal amino acid digestibility values were similar in some ingredients, but significantly lower or higher in others than the corresponding excreta values. 4. Average ileal and excreta amino acid digestibilities in sorghum and maize were similar, but significant differences were observed for individual amino acids. In contrast, ileal amino acid digestibility values were higher than the corresponding excreta digestibility values in wheat. 5. The average ileal and excreta digestibilites of amino acids in the 3 soyabean meal samples were similar although small, but significant differences were noted for individual amino acids. Site of measurement had no effect on the digestibility of amino acids in canola meal. Digestibilities of valine, isoleucine, phenylalanine, histidine, glutamic acid, alanine and tyrosine in sunflower meal and those of valine, methionine, isoleucine, leucine, lysine, glutamic acid and alanine in cottonseed meal were lower by excreta analysis. 6. Digestibilities in animal protein meals, with the exception of blood meal and fish meal, were consistently higher by excreta analysis. Ileal-excreta differences in individual amino acid digestibilities were more evident in feather meal, meat meal and meat-and-bone meal. 7. Threonine and valine were the indispensable amino acids that were more frequently influenced by the site of measurement. Of the dispensable amino acids, aspartic acid, serine, glutamic acid and alanine were the most affected. 8. Differences determined between ileal and excreta digestibilities in the present study clearly demonstrate that amino acid metabolism by hindgut microflora in chickens may be substantial and that digestibilities measured in the terminal ileum are more accurate measures of amino acid availability than those measured in the excreta.  相似文献   

13.
The growing pig is an established model animal for humans to determine protein digestibility to the end of the small intestine. An ileal amino acid digestibility assay based on the laboratory rat offers an alternative. True ileal amino acid digestibility in high quality refined protein sources was determined and compared between the laboratory rat and the growing pig. Both species of animals were fed their daily ration in nine separate meals. Ileal digesta were collected at slaughter and chromic oxide was used as an indigestible marker. For several of the amino acids examined, there were no significant (p < 0.05) differences between the two species for true ileal amino acid digestibility, but for aspartic acid, serine, cysteine, methionine, tyrosine, phenylalanine and histidine, significant (p < 0.05) interspecies differences were found. The overall average amino acid digestibility, for all amino acids and all diets, was 95.8% for the pig and 96.1% for the rat. Cysteine digestibility was highly variable between individual animals fed the same diet. The extent of amino acid digestion and absorption appears to be broadly similar across the two species, but some important differences in digestibility were recorded.  相似文献   

14.
The composition of a commercially available sample of dried poultry manure (DPM) was determined and its nutritive value for the laying hen was examined using colostomised birds. The true digestibility coefficients of the true protein, crude fat, uric acid, total organic matter and carbohydrate were found to be 64.2, 69.5, 91.2, 25.5 and 23.1% respectively by regression analysis of absorbed vs. ingested nutrients. The true digestibilities of some of the constituent amino acids were found to range from 24.7% (for valine) to 76.4% (for serine). The absorption of calcium and phosphorus was characteristic of the individual bird and ranged from 1.2 to 45.3 % for calcium and from 7.5 to 46.2 % for phosphorus. The classical and nitrogen‐corrected metabolisable energy values were found to be 3.50 ± 0.16 and 3.35 ± 0.13 MJ/kg of dry matter respectively. It is concluded that DPM contains nutrients of value to the laying hen and that it could be incorporated into poultry diets in which energy content is of secondary importance and where use could be made of the calcium and phosphorus contents.  相似文献   

15.
应用正常及去盲肠成年白来航公鸡各20只，比较了鱼粉、豆饼、菜籽饼、棉仁饼的氨基酸利用率。结果表明：鱼粉和棉仁饼的17种氨基酸的表观及真利用率在两组问差异不显著；豆饼必需氨基酸表观氨基酸利用率中有6种氨基酸两组间差异显著成极显著，真利用率中只有2种氨基酸两组间差异显著；菜籽饼必需氨基酸表观氨基酸利用率有2种氨基酸两组间差异显著，真利用率两组问差异不显著。从鸡的正常生理角度考虑，作者认为：用正常试验鸡并以氨基酸真利用率为指标，更能客观地反映常用蛋白质饲料的氨基酸利用率。  相似文献   

16.
1. Eight diets based on maize starch and sucrose were prepared, containing ground maize husks or semi-purified wood cellulose, with 30, 60, 90 or 120 g fibre source/kg diet dry matter (DM). 2. The diets were precision-fed to 12 caecectomised and 12 intact adult male domestic fowls. The quantities of amino acids and faecal N excreted over the 48 h following each feeding were measured. 3. Diet had no influence on the quantities of endogenous amino acids or endogenous faecal N excreted. 4. A proportion of the amino acids and N of the maize husks and of endogenous origin appeared to be degraded or retained in the caeca of intact birds.  相似文献   

17.
Poultry diets are formulated based on requirements of birds reared without access to pasture. Consumer demand for organic and free-range poultry has resulted in an increase in the use of certified organic feed. Organic poultry may have the opportunity to utilize nutrients found in forage. The addition of exogenous enzymes and manipulation of cecal microbial populations may affect the utilization of forage nutrients. The objectives of this study were as follows: 1) to determine AMEn and TMEn of organic grower diets with or without nonstarch polysaccharide enzyme supplementation and compare these values to a conventional grower diet, 2) to determine AMEn, TMEn, and true amino acid digestibility (TAAD) of forage samples with or without nonstarch polysaccharide enzyme supplementation, and 3) to determine if cecum modification affects forage AMEn, TMEn, and TAAD. The experiment was conducted using cecectomized, intact, and intact grass-fed roosters as models. Enzyme supplementation increased AMEn and TMEn values for organic feeds but not forage. Bird type had no effect on AMEn and TMEn for any treatment. The TAAD of forage was not significantly affected by enzyme supplementation. However, trends in bird type effect were observed for several amino acids.  相似文献   

18.
This study was designed to quantify the effect of soyhulls on N and AA digestibilities of soybean meal for growing pigs. Soyhulls were incorporated into 17% CP diets containing 33.25% soybean meal (SBM) at 0, 3, 6, or 9% (as-fed basis) and fed to 35-kg barrows to determine their effect on apparent and true digestibility of DM, GE, N, and AA measured at the terminal ileum. Positive and negative control diets containing 1.05% lysine were formulated with 35% SBM and 27% soy protein concentrate (SPC), respectively. A low-protein, casein-based diet was used to estimate endogenous AA losses. Soyhulls were incorporated into experimental diets at the expense of cornstarch, and SBM levels were adjusted to accommodate the contribution of CP from soyhulls. Fourteen pigs were surgically fitted with simple T-cannula at the distal ileum and fed the seven semipurified cornstarch diets based on a replicated 7 x 7 Latin square design. Each period lasted 7 d, with diet acclimation from d 1 to 5 and ileal sample collection for 12 h on d 6 and 7. Feed was offered at a level of 90 g/kg BW(0.75) in two equal portions at 0800 and 2000. Apparent ileal digestibilities of DM and GE decreased approximately six percentage units with the addition of soyhulls (linear, P < 0.05), whereas N was not affected. Both apparent and true ileal digestibilities of arginine, histidine, lysine, phenylalanine, aspartic acid, serine, and tyrosine also exhibited a decrease (linear, P < 0.05) of up to five percentage units with the addition of soyhulls. True ileal lysine digestibility of SBM decreased from 90.3 to 87.7% with the addition of 9% soyhulls. The endogenous nutrient fraction measured at the distal ileum was rich in proline, glutamic acid, and glycine, with losses greater than 1,000 mg/kg of DMI for each AA, and contained minimal amounts of tryptophan, methionine, and cystine. The current data suggest that a 0.2% decrease in some true ileal indispensable AA digestibilities may result with each 1% increase in soyhull inclusion in semipurified diets containing SBM as the sole source of AA as fed to growing pigs.  相似文献   

19.
In situ and digestion studies were conducted to evaluate feather meal (FTH), blood meal (BM), and meat and bone meal (MBM) for escape protein content, amino acid composition of the escape protein, true protein digestibility, and digestibility of the individual amino acids. Following 12 h of ruminal incubation, escape protein values were 73.5, 92.4, and 60.8% of CP for FTH, BM, and MBM, respectively. Blood meal and MBM were poor sources of sulfur amino acids (SAA), whereas FTH was a good source. Most of the SAA of FTH, however, was Cys, with very little Met. True protein digestibilities were not different for the protein sources (P > .15), ranging from 86.7 to 94.0% of the CP. However, digestibilities of the individual amino acids were quite different. Two growth studies were conducted to evaluate FTH as a source of SAA for growing cattle. The first study used 120 steers (228 +/- 15 kg) supplemented with urea, MBM, MBM plus 1% FTH, or MBM plus 2% FTH. Additionally, incremental amounts of rumen-protected Met were added to treatments containing MBM. Supplementation of MBM increased (P < .05) ADG compared with the urea control. Addition of FTH to MBM resulted in a linear (P < .01) increase in ADG. However, addition of rumen-protected Met to MBM plus FTH treatments further improved gains. Although FTH is an effective source of SAA, Met probably was first-limiting. The second study used 90 steers (243 +/- 18 kg) supplemented with BM plus incremental amounts of SAA from either FTH or rumen-protected Met. Addition of SAA improved ADG compared with BM alone (P < .05). Rumen-protected Met as a source of SAA improved ADG compared with FTH (P < .05). The SAA from FTH promoted a gain response equal to 50% of the response obtained with rumen-protected Met. Formulation of ruminant diets for metabolizable amino acids must account for escape value and digestibility of each individual amino acid. Feather meal is an effective source of SAA; however, Cys supplies over five times the amount supplied by Met.  相似文献   

20.
选用24只2 kg左右的蛋公鸡,随机分组进行4个处理,每个处理6只鸡。前3个处理分别给每只鸡强饲占体重4%的待测原料(豆粕、玉米蛋白粉和味精菌体蛋白),第4个处理作为内源对照组,测定内源排泄量,以评定味精菌体蛋白对鸡蛋白质和氨基酸利用率的影响。结果表明,味精菌体蛋白粗蛋白含量达到71.45%,分别比豆粕和玉米蛋白粉高64.03%和22.32%;味精菌体蛋白粗蛋白表观消化率和真消化率、总氨基酸表观消化率和真消化率均极显著低于豆粕和玉米蛋白粉(P<0.01);而干物质表观消化率和真消化率三者间无显著差异(P>0.05);在已测定的17种氨基酸中,除甘氨酸外,味精菌体蛋白粉其他氨基酸表观消化率和真消化率均极显著低于豆粕和玉米蛋白粉(P<0.01)。这表明味精菌体蛋白的蛋白质和氨基酸利用率低于豆粕和玉米蛋白粉。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号