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1.
Four colostomized laying hens per group were given a ration of barley and soya bean oil meal (SBM) with 12.5, 25.0 and 37.5% SBM resp. The crude protein intakes were 14.0, 17.7 and 21.4 g per animal and day. The lysine intake raised from 681 mg (group 1) to 1275 mg (group 3) per animal and day. The digestibility of dry matter and of the N-free extracts of the ration decreased with the rising SBM portion in the ration. The digestibility of crude protein remained constant. The investigated amino acids (Lys, His, Arg, Cys, Met) were higher digested in the 37.5% SBM ration than in the 12.5% SBM ration. The following digestibility values for SBM were found by means of the difference method: Dry matter 52.5%, crude protein 83.1%, crude fat 51.7%, crude fibre 5.5%, N-free extracts 50.6%. The level of the SBM did not influence the digestibility of the crude nutrients. The apparent digestibility of lysine from SBM depended on the level of intake and was found to be 82.3, 83.4 and 89.0%, resp. There were no differences in the digestibility of other amino acids.  相似文献   

2.
In two experiments with colostomized broiler hens the influence of a straw meal supplement on the apparent digestibility of the amino acids of the ration and the 15N labelled basic amino acids in wheat was studied. In experiment 1 the animals received 120 g mixed feed plus 0, 20, 30 and 40 g straw meal per animal and day. The digestibility of the amino acids decreased on average from 86% to 83%, 80% and 79% with the growing straw intake. In contrast to the control variant, 20 g straw meal intake resulted in a significant decrease of digestibility for lysine, histidine, glycine, tyrosine, phenylalanine, cystine and methionine. 30 and 40 g straw meal reduced significantly the digestibility of all amino acids with the exception of arginine. The amino acid composition of the crude protein in faeces changed only very slightly due to the straw supplement. In experiment 2 15N labelled wheat was a component of the ration. Of the 15N labelled amino acids lysine, histidine and arginine, 88, 90 and 95% were apparently digested. The adaptation of the animals to straw meal intake did not change the digestibility of the amino acids.  相似文献   

3.
The digestibility of the nutrients of Fermosin was tested on pigs and the following values were ascertained: organic matter=86%, crude protein=89% and N-free extractives=83%. The net energy ascertained on the basis of the content of nutrients and the digestibility of the nutrients of Fermosin amounts to 617 energetic feed units for pigs/kg dry matter. The true digestibility of the amino acids of Fermosin was determined on pigs and chicken. For lysin the true digestibility was ascertained as 95% (pigs) and 73% (Broilers). Due to the different digestion abilities of the two animal species, corresponding differences in the digestibility of the other amino acids were found as well.  相似文献   

4.
In this study, we examined the variations between the difference method and the enzyme-hydrolyzed casein method for determining endogenous amino acid loss and the true amino acid digestibility in ducks fed normal protein-containing diets. These methods were compared to the nitrogen-free (N-free) diet method. The difference method was based on soybean meal as the only protein source, with the experimental diets containing crude protein levels at 15% and 20%. The enzyme-hydrolyzed casein method was based on enzyme-hydrolyzed casein meal as the protein source, with the experimental diet containing a crude protein level of 17.5%. The N-free diet was prepared with starches and paper fibers. In each method, 64 Tianfu meat drakes (7-weeks-old) with an average body weight of 2.77 ± 0.16 kg were used and divided into four groups, and fed four different diets. Each group contained four replicates of four drakes and they were force fed trial diets according to the Sirbald method for detecting their apparent amino acid digestibility, endogenous amino acid loss and true amino acid digestibility. The results demonstrated that using the difference, enzyme-hydrolyzed casein and N-free diet methods, endogenous amino acid losses were 0.9946, 1.2243 and 0.9297 mg/g dry matter intake (DMI), respectively. The true amino acid digestibility measured by the difference method was 88.93% ± 4.43%. Using the enzyme-hydrolyzed casein method with two dietary crude protein levels of 15% and 20%, the digestibility was 91.15% ± 4.33% and 91.97% ± 4.16%, respectively, and by the N-free diet methods with two dietary crude protein levels of 15% and 20%, it was 88.55% ± 4.29% and 88.82% ± 4.61%, respectively. The results suggested that when the dietary protein level was 15% to 20 %, the true amino acid digestibility and endogenous amino acid loss as determined by the difference method was more accurate than the values determined by the enzyme-hydrolyzed casein method.  相似文献   

5.
Two groups of four pigs each were fed ad libitum with rations containing 70.7% barley, 7.7% fish meal, 0.7% Sussopan, 0.9% mixed minerals and 20% straw meal. Group 1 received partly hydrolysed straw meal, group 2 untreated straw meal. When those rations were given, weight increase performances of 767 g per animal and day in group 1 and 537 g per animal and day in group 2 were achieved in a preliminary 30-day feeding period. On the basis ofthe weight of the feed remnants, a consumption of 19.7% dry matter of the straw meal (group 1) resp. 18,5% (group 2) of the total intake of dry matter could be ascertained. At an average live weight of 93 kg (group 1) resp. 87.5 kg (group 2) the digestibility of both rations was examined. A significant difference was only found for the crude protein fraction with an apparent digestibility of 74.6% in group 1 and of 79.1% in group 2. Those pigs which received partly hydrolysed straw meal consumed 71.4 g N per animal and day, of which 25,4% were excreted in feces and 32.4% in urine. Those animals which were fed with untreated straw meal consumed 62.9 g N per animals and day of which 20.8% were excreted in feces and 49.7% in urine. The higher N-excretion in feces could also be proved for most amino acids the feeding with partly hydrolysed straw meal. For arginine, serine, glutamic acid, proline, isoleucine and Leucine these differences were significant. Differences concerning N-retention could not be found between the groups. 25% of the organic matter of the partly hydrolysed straw meal, 9.4% of the crude fibre and 44.2% of the N-free extractives were digestible. Of the untreated straw, 12.9% of the organic matter, 5.5% ofthe crude fibres and 21.7% of the N-free extractives were digestible. 193 EFpig were calculated for partly hydrolysed and 105 EFpig for untreated straw meal per kg dry matter. The result of substracting the CaCl2 of the partly hydrolysed straw meal is 205 EFpig per kg dry matter of the straw.  相似文献   

6.
The crude protein digestibility and the amino acid absorption of six female pigs (average live weight 61 kg) with duodenal and ileocecal re-entrant cannulae, which were fed with a wheat + wheat gluten + lysine ration and an N-free ration, were determined in various segments of the intestines. Comparative experiments concerning the N-metabolism with pigs without and with cannulae showed that the animals renormalised their metabolism 14 days after narcosis and fistulation of the intestines. The extents of secretion and absorption of the various amino acids vary as it is shown from the values of the apparent and true digestibility resp. rate of passage through various segments of the intestines. While for methionine and glutamic acid absorption exceeds endogenous secretion already in the duodenum, the amino acids with a high endogenous quota (glycine, alanine, threonine, tryptophan) are, even at the terminal ileum, not as well absorbed as the others. Methionine is obviously synthesised on a large scale by the colon flora and excreted in feces. The fractionation of the duodenal and ileum chyme after feeding wheat + wheat gluten + lysine as well as N-free mixture, into the fractions "solid particles", "peptides-free amino acids" and "proteines precipitable by trichlor-acetic acid" supplies information on the degree of protein degradation in various segments of the intestines.  相似文献   

7.
In this study,we examined the variations between the difference method and the enzyme-hydrolyzed casein method for determining endogenous amino acid loss and the true amino acid digestibility in ducks fed normal protein-containing diets.These methods were compared to the nitrogen-free(N-free)diet method.The difference method was based on soybean meal as the only protein source,with the experimental diets containing crude protein levels at 15% and 20%.The enzyme-hydrolyzed casein method was based on enzyme-hydrolyzed casein meal as the protein source,with the experimental diet containing a crude protein level of 17.5%.The N-free diet was prepared with starches and paper fibers.In each method,64 Tianfu meat drakes(7-weeks-old)with an average body weight of 2.77±0.16 kg were used and divided into four groups,and fed four different diets.Each group contained four replicates of four drakes and they were force fed trial diets according to the Sirbald method for detecting their apparent amino acid digestibility,endogenous amino acid loss and true amino acid digestibility.The results demonstrated that using the difference,enzyme-hydrolyzed casein and N-free diet methods,endogenous amino acid losses were 0.9946,1.2243 and 0.9297 mg/g dry matter intake(DMI),respectively.The true amino acid digestibility measured by the difference method was 88.93%±4.43%.Using the enzyme-hydrolyzed casein method with two dietary crude protein levels of 15% and 20%,the digestibility was 91.15%±4.33% and 91.97%±4.16%,respectively,and by the N-free diet methods with two dietary crude protein levels of 15% and 20%,it was 88.55%±4.29% and 88.82%±4.61%,respectively.The results suggested that when the dietary protein level was 15% to 20 %,the true amino acid digestibility and endogenous amino acid loss as determined by the difference method was more accurate than the values determined by the enzyme-hydrolyzed casein method.  相似文献   

8.
Digestibility trials were carried out with calves, aged 3, 5, 7, 9, and 11 weeks, which were fed with feedstuffs of various energy and protein levels (various amounts of dried skim milk supplement with 146, 219, 323 g per day of the milk replacer Laktin) plus concentrate and hay. The purpose of the experiment was to find out what effect the amount of milk replacer varying daily had on the digestibility of the nutrients. The experiments confirm that the amount of milk replacer has a great influence on the digestibility of the crude fat. The amount of digestible crude fat consumed with the feed considerably influcenced the digestibility of the energy, it had little influence on the digestibility of the other nutrients, however. With increasing age the calves received more plant protein sources with a lower biologic value. Thus the digestibility of the protein in the complete ration was diminished as well. This shows that the digestibility was influenced by the protein quality, not, however, by the amount of crude protein. The digestibility of the dry matter andthe organic matter as well as of the N-free extractives in the feed ration diminished according to the changed composition with the increasing age of the animals; in constrast to this the digestibility of the crude fibres increased gradually.  相似文献   

9.
Two trials were conducted to evaluate the effects of protein source (48% CP soybean meal or casein) and carbohydrate source (25% dextrose or 25% lactose) on digestibility and digesta flow rate in early-weaned pigs. Diets contained 10% crude soybean oil and were formulated to contain 3.5 g lysine, 2.3 g Ca and 2.0 g P per 1,000 kcal DE of diet. In Trial 1, nutrient digestibility was greater for older than for younger pigs. Apparent digestibilities for energy, DM, CP and fat were lower (P less than .08) for younger and older pigs fed soybean meal rather than casein. Digestibility of soluble carbohydrates was less (P less than .02) for younger pigs fed soybean meal rather than casein as a protein source. Fat digestibility was lower (P less than .05) in younger pigs fed dextrose than in pigs fed lactose. A protein X carbohydrate source interaction (P less than .01) existed for fat digestibility by older pigs. In Trial 2, pigs were euthanatized, and digestibilities anterior to the ileum and the colon (pre-ileal and pre-cecal) were determined. At the ileum, fat digestibility was lower (P less than .05) for pigs fed soybean meal, whereas CP digestibility was lower (P less than .05) for pigs fed either soybean meal or dextrose. A protein X carbohydrate interaction was observed for ileal digestibilities of DM (P less than .06) and total carbohydrates (P less than .03) with lowest values obtained for the soybean meal plus dextrose diet. For casein diets, digestibility values were similar between the two carbohydrate sources.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
By means of the difference method an apparent digestibility of 88.3% of the organic matter, 50.4% of the crude protein, 25.1% of the crude fat, 12.7% of the crude fibre and 94.2% of the N-free extractives of Thai tapioca meal was ascertained in colostomized laying hens. It is possible to use 20% tapioca meal in the feed for chickens and pullets without a decrease in performance. Two experiments with laying hens were carried out with 5-30% tapioca. Egg production decreases slightly with a tapioca quota of 10% and more. This is why a feeding limit of 5% is recommended. With 20% tapioca the decrease of performance was 1.5%. Tapioca meal diminishes the intensity of the yellow of the yolks. Cereals may be partially substituted by tapioca in the feed for chickens, pullets and laying hens.  相似文献   

11.
以常规成分为变量估测饲料中必需氨基酸含量的初步探讨   总被引:1,自引:1,他引:0  
本文探讨了玉米、小麦、高粱、豆饼(粕)、菜籽饼(粕)、花生饼(粕)、国产鱼粉、小麦麸、米糠、米糠饼、米糠粕、苜蓿草粉、大豆、黑大豆、蚕豆、豌豆的粗蛋白、粗纤维、粗脂肪和粗灰分与必需氨基酸的多元回归方程和粗蛋白与必需氨基酸之间的一元回归方程。一元回归方程估测误差(RSD)略高于多元回归方裎估测误差,但相关程度两者基本一致。方差分析表明,玉米、小麦、花生饼(粕)、国产鱼粉、小麦麸、米糠、苜蓿草粉、黑大豆、大豆、蚕豆、豌豆的常规成分与必需氨基酸含量存在显著的相关关系(P<0.05);大麦、高粱、米糠饼(粕)和菜籽饼(粕)常规成分与苯丙氨酸、组氧酸、精氨酸等必需氨基酸存在显著扣关关系(P<0.05),与赖氨酸、亮氨酸、蛋氨酸等必需氨基酸不存在相关关系(P>0.05);豆饼(粕)常规成分与必需氨基酸不存在相关关系。利用朱参加计算的玉米和小麦麸样品数据资料比较了粗蛋白与必需氨基酸之间的一元回归方程估测值、按粗蛋白递增比例计算值和实测值之间的差异。表明用回归方程估测较按粗蛋白质递增比例推算,更接近于实际测定值,具有显著相关关系的回归方程应用于生产以估测某些必需氨基酸含量是可行的。  相似文献   

12.
Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent- extracted soybean meal (n = 5) were obtained from People’s Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   

13.
In experiments with colostomized broiler hens apparent digestibility of the crude nutrients of the ration after straw meal supplements of 20, 30 and 40 g per animal was determined. In addition, the 15N digestibility of straw meal and wheat was ascertained on the basis of straw meal supplements. The digestibility of the crude nutrients of the rations decreased significantly (P less than 0.05) after the straw meal supplement. The adaptation of the test animals to the straw meal intake resulted, at a daily consumption of 20 g straw meal, in an increase of the apparent crude fat digestibility (P less than 0.05) in dependence on the time of straw meal feeding, in which the original values without straw meal supplement were not reached. The digestibility of the 15N excess (15N') of the wheat was, at 86 +/- 1%, largely independent of the straw meal intake. The apparent digestibility of the straw-15N excess in broiler hens of 42 +/- 8 to 55 +/- 2% is surprisingly high.  相似文献   

14.
The crude protein content and amino acid profile of seven feedstuffs (linseed meal, maize gluten meal, rapeseed meal, rapeseed meal protected, soybean meal, fullfat soybean extruded and sunflower meal) were determined before and after ruminal incubation for 16 h in three bulls with large rumen cannulas. The intestinal disappearance of amino acids was measured using mobile bag technique. Ruminal incubation affected amino acid profile of all experimental feedstuffs. Crude protein degradation varied from 29.3% for maize gluten meal to 86.4% for rapeseed meal. A tendency towards increased disappearance was observed for glutamic acid, histidine, lysine and proline and decreased disappearance for branched-chain amino acids. The intestinal crude protein digestibility was higher than > 80%, except rapeseed meal (66.4%) and sunflower meal (77.8%). The least digestible individual amino acids were methionine and isoleucine in rapeseed meal, histidine and methionine in rapeseed meal protected and arginine in sunflower meal. In general, the lowest amino acid digestibilities were found in feedstuffs with the highest fibre content. The feedstuffs show that they have different potential for supplying of limiting amino acids. Of particular value are the feedstuffs with low crude protein degradability in the rumen and high intestinal digestibility of amino acids.  相似文献   

15.
ABSTRACT: Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent-extracted soybean meal (n = 5) were obtained from People's Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   

16.
The apparent ileal digestibility of amino acids in 8 feed ingredients was determined using 14-, 28- and 42-d-old male broiler chickens. The ingredients included three cereals (wheat, sorghum and maize), one cereal by-product (mill run), three oilseed meals (canola, cottonseed and soybean meals) and one animal protein meal (meat and bone meal). Dietary crude protein in the assay diets was supplied solely by the test ingredient. All diets contained 20 g/kg acid-insoluble ash as an indigestible marker, and each diet was offered ad libitum in mash form to 5 replicate pens from 11 to 14 d, 25 to 28 d and 39 to 42 d post-hatching. There were 12, 6 and 6 birds per pen for the 14, 28 and 42 d samplings, respectively. The results suggest that the age of broilers significantly influenced the apparent ileal digestibility of amino acids. The effects, however, varied among amino acids and ingredients. In wheat, the digestibility of most amino acids was higher in 14- than in 28- and 42-d-old broilers. In maize, the digestibility coefficients of amino acids were higher at 28 and 42 d than at 14 d. The digestibility coefficients in maize and wheat at 28 and 42 d were similar. The digestibility of amino acids in sorghum at 42 d was higher than those at 28 d, but similar to those at 14 d except for histidine, lysine, serine and glycine, which were significantly higher at 42 d. Digestibility of amino acids in sorghum was similar between 14 and 28 d except for isoleucine, leucine, phenylalanine, glutamic acid and alanine. The digestibility of amino acids in mill run at 42 d was significantly higher than those at 14 and 28 d. There were no differences in digestibility between 14 and 28 d. In general, the digestibility of amino acids in canola meal, soybean meal and, meat and bone meal was higher at 28 and 42 d compared to those at 14 d, and similar between 28 and 42 d of age. In cottonseed meal, age had no effect on the digestibility coefficient of amino acids, except for lysine and arginine, which increased with age. Analysis of the combined results for the 8 feed ingredients showed that, in general, the digestibility coefficients of amino acids increased with advancing age of broiler chickens.  相似文献   

17.
固态发酵对复合蛋白质饲料营养价值改善效果的研究   总被引:7,自引:1,他引:6  
本文旨在研究同态发酵对复合蛋白质饲料(CPF)营养成分和养分利用效率的改善效果.将产朊假丝酵母、枯草芽孢杆菌和乳酸杆菌接种到CPF后发酵3 d,干燥制得发酵复合蛋白质饲料(FCPF).在测定豆粕(SBM)、CPF、FCPF常规养分和氨基酸含量基础上进行消化代谢试验.选择体重为(24.36±1.78)kg的杜×长×大生长猪24头,随机分为4组,每组6个重复,每个重复1头猪,分别饲喂无氮日粮和以SBM、CPF及FCPF作为唯一蛋白质源配制的半纯合日粮,采用无氮日粮法测定SBM、CPF和FCPF对生长猪的蛋白质、能量消化利用率以及氨基酸回肠消化率.预试期4 d,正试期4 d.结果表明:固态发酵极显著提高了FCPF的粗蛋白质、真蛋白质、钙和总磷含量(P<0.01);除精氨酸外,氨基酸含量均有所提高.与CPF相比,FCPF蛋白质消化利用率和能量消化率均极显著升高(P<0.01);氨基酸表观消化率显著或极显著的升高(P<0.05或P<0.01);除Gly以外,FCPF各氨基酸真消化率均显著或极显著的升高(P<0.05或P<0.01).FCPF大部分营养特性接近或优于SBM.由此可知,固态发酵可改善CPF的营养特性,提高其在20~50 kg生长猪上的养分消化利用率.  相似文献   

18.
枯草芽孢杆菌固体发酵豆粕条件的优化   总被引:1,自引:0,他引:1  
本试验采用枯草芽孢杆菌对豆粕进行固体发酵,通过正交试验探讨不同碳源组合、发酵时间、培养温度、水分比例、接种菌量等因素对发酵豆粕粗蛋白质增加率和蛋白质水解度的影响。结果表明,影响枯草芽孢杆菌固体发酵豆粕粗蛋白质增加率的条件因素的主次顺序为玉米粉比例>培养时间>温度>麸皮比例>水分比例>次粉比例>接种菌量,表观分析固体发酵条件最佳组合为A3B1C3D3E2F2G1,粗蛋白质增加率达到28.05%;影响发酵豆粕蛋白质水解率的条件因素的主次顺序为温度>培养时间>玉米粉比例>接种菌量>麸皮比例>次粉比例>水分比例,表观分析固体发酵条件最佳组合为A2B3C1D3E3F3G1,蛋白质水解度达到46.46%。枯草芽孢杆菌固体发酵豆粕的粗蛋白质增加率与蛋白质水解率存在明显的正相关(R2=0.556)。  相似文献   

19.
High fiber co-products from the copra and palm kernel industries are by-products of the production of coconut oil and palm kernel oil. The co-products include copra meal, copra expellers, palm kernel meal, and palm kernel expellers. All 4 ingredients are very high in fiber and the energy value is relatively low when fed to pigs. The protein concentration is between 14 and 22 % and the protein has a low biological value and a very high Arg:Lys ratio. Digestibility of most amino acids is less than in soybean meal but close to that in corn. However, the digestibility of Lys is sometimes low due to Maillard reactions that are initiated due to overheating during drying.Copra and palm kernel ingredients contain 0.5 to 0.6 % P. Most of the P in palm kernel meal and palm kernel expellers is bound to phytate, but in copra products less than one third of the P is bound to phytate. The digestibility of P is, therefore, greater in copra meal and copra expellers than in palm kernel ingredients. Inclusion of copra meal should be less than 15 % in diets fed to weanling pigs and less than 25 % in diets for growing-finishing pigs. Palm kernel meal may be included by 15 % in diets for weanling pigs and 25 % in diets for growing and finishing pigs.Rice bran contains the pericarp and aleurone layers of brown rice that is removed before polished rice is produced.Rice bran contains approximately 25 % neutral detergent fiber and 25 to 30 % starch. Rice bran has a greater concentration of P than most other plant ingredients, but 75 to 90 % of the P is bound in phytate. Inclusion of microbial phytase in the diets is, therefore, necessary if rice bran is used. Rice bran may contain 15 to 24 % fat, but it may also have been defatted in which case the fat concentration is less than 5 %. Concentrations of digestible energy(DE) and metabolizable energy(ME) are slightly less in full fat rice bran than in corn, but defatted rice bran contains less than 75 % of the DE and ME in corn. The concentration of crude protein is 15 to 18 % in rice bran and the protein has a high biological value and most amino acids are well digested by pigs. Inclusion of rice bran in diets fed to pigs has yielded variable results and based on current research it is recommended that inclusion levels are less than 25 to 30 % in diets for growing-finishing pigs, and less than 20 % in diets for weanling pigs.However, there is a need for additional research to determine the inclusion rates that may be used for both full fat and defatted rice bran.  相似文献   

20.
Based on the fact that the insufficient supply of agricultural domestic animals with drinking water in tropical and subtropical regions is often the factor limiting their performance, the effect of different drinking water supply of sheep (ad libitum, 54% of ad libitum and 27% of ad libitum) on various parameters was studied. A water supply reduced to 54 and 27% resp. diminished dry matter intake to 84% and 45% resp. A water supply reduced to 54% improved the digestibility of organic matter, crude fibre, crude cellulose and N-free extractives, it was, however, not significant. A reduction to 27% of the ad libitum water supply improved the digestibility of all crude nutrients, significantly, however, only that of organic matter, crude fibre, crude cellulose and N-free extractives. In comparison with a supply of water reduced to 54%, a water supply reduced to 27% also resulted in an improvement of the digestibility of all crude nutrients. Both the reduction of the ad libitum water supply and the increasing time interval for the sampling of rumen fluid resulted in an increased concentration of volatile fatty acids in the rumen fluid, which was sampled 15 min, 1 hour and 2 hours after feeding.  相似文献   

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