共查询到20条相似文献，搜索用时 22 毫秒
1.
Two pig experiments were conducted using a methionine (Met)-deficient feather meal-corn-soybean meal basal diet (13% CP; 3,400 kcal ME/kg diet, .126% Met, 456% cystine) supplemented with an amino acid mixture (lysine, tryptophan, histidine, threonine and phenylalanine) to determine the Met requirement of finishing pigs between 50 and 80 kg live weight. Using young chicks in a Met bioavailability growth assay and cecectomized adult cockerels in a Met digestibility assay, the Met-deficient basal diet was found to contain .115% bioavailable and .110% digestible Met. These results gave a bioavailability estimate (relative to DL-Met set at 100%) of 91.3 +/- 2.5% and a true digestibility estimate of 87.0 +/- 2.2% for Met in the basal pig diet. In Exp. 1, 21 crossbred pigs averaging 61 kg initially were individually fed diets containing .115, .165 or .215% bioavailable Met for 21 d. Average daily gain and gain:feed ratio increased quadratically (P less than .05) as level of Met increased. In Exp. 2, 30 crossbred pigs averaging 53 kg were individually fed diets containing .115, .135, .155, .175 or .195% bioavailable Met for 27 d. Daily gain and gain;feed ratio responded linearly (P less than .01) as Met level increased. Based on the results of Exp. 2, the bioavailable Met requirement of finishing pigs in the weight range 50 to 80 kg was estimated to be .182% of the diet. Assuming an 88% bioavailability of Met in commercial diets based on corn and soybean meal, the total Met level needed in practice would be .207%. If 55% of the finishing pig's sulfur amino acid need can be furnished by cystine, the total sulfur amino acid requirement would be .45% of the diet. 相似文献
2.
Three experiments were conducted with young pigs to measure the availability of tryptophan in soybean meal, meat and bone meal, cottonseed meal, corn and sorghum. In Exp. 1, a 17.5% crude protein corn and gelatin-based diet, deficient in tryptophan, was supplemented with graded levels of L-tryptophan to establish the growth response of 10- to 20-kg pigs to graded additions of dietary tryptophan. From these data the requirement for maximal growth was calculated to be .16% of the diet using a broken-line model. In Exp. 2, the effects of excess amino acids in a test feedstuff, i.e., soybean meal, on the growth assay method for estimating tryptophan availability was evaluated. The addition of excess crystalline amino acids to the basal diet in proportions equal to the excesses contributed by a test level of soybean meal resulted in a 17.7 percentage unit reduction in the estimate of tryptophan availability (82.3%). When the standard diet was supplemented with amino acids to provide the pattern of excess amino acids found in the corn-gelatin basal diet with added soybean meal, the availability of tryptophan in soybean meal was estimated to be 95.2%. In Exp. 3, the tryptophan availabilities for meat and bone meal, cottonseed meal, corn and sorghum were estimated to be 82.2%, 80.9%, 94.0% and 86.4%, respectively. The diets used in this experiment were supplemented to contain excesses of individual amino acids in the same proportions as found in the basal diet, with the test feed ingredient added as a source of tryptophan. In these experiments the tryptophan content of the various feedstuffs was measured by ion-exchange liquid chromatography following alkaline hydrolysis. 相似文献
3.
Comparative effects of individual amino acid excesses when added to a corn-soybean meal diet: effects on growth and dietary choice in the chick 总被引：2，自引：0，他引：2
Six experiments were conducted with 8-d-old crossbred chicks to evaluate the effects of 4% excesses of DL-methionine (Met), L-phenylalanine (Phe), L-tryptophan (Trp), L-lysine (Lys), L-histidine (His), L-threonine (Thr), L-isoleucine (Ile), L-arginine (Arg), L-valine (Val) or L-leucine (Leu) on growth or dietary "choice" (i.e., self-selection) when added to 23% protein corn-soybean meal (C-SBM) diets. Arginine and His were supplied as the free base and Lys as Lys X acetate to avoid acid-base problems. In the growth studies, weight gain was reduced 92, 79, 53, 50, 47, 31, 29, 15, 9, 4 and 0% by additions of 4% Met, Phe, Trp, His, Lys, Tyr, Thr, Ile, Arg, Val and Leu, respectively. Improvements (P less than .05) in weight gain, feed intake and gain/feed occurred by addition of 1% Arg to the C-SBM diet supplemented with 4% excess Phe or Tyr. Addition of 1% Arg to the C-SBM diet supplemented with 4% excesses of most of the other amino acids also tended to improve performance, although diets imbalanced with Lys, Val or Leu did not respond to supplemental Arg. Self-selection studies revealed that chicks preferred the C-SBM diet containing 4% excess Lys over diets containing 4% excesses of Met, Thr, Arg or Trp. Moreover, chicks preferred diets with 4% excess Met, Thr or Arg over those containing an equal excess of Trp. When given a choice between the C-SBM diet and this diet supplemented with 4% Leu, chicks consumed similar quantities of both diets. 相似文献
4.
Limiting amino acids in an 11% crude protein corn-soybean meal diet for growing pigs 总被引：1，自引：0，他引：1
Three experiments were conducted to test the hypothesis that methionine, isoleucine, valine or nitrogen either singly or in combination are limiting in an 11% crude protein, lysine-tryptophan-threonine-supplemented, corn-soybean meal diet for growing pigs. A 16% crude protein diet was used as a positive control in each experiment and all amino acid additions were made, at a minimum, to equal requirements. Average initial weights were 21.3 kg, 23.0 kg and 19.1 kg in Exp. 1, 2 and 3, respectively. The experiments averaged 4 wk in duration. In Exp. 1 and 2, neither the addition of glutamic acid as a source of nitrogen, nor methionine to the 11% diet resulted in any improvement (P greater than .20) in rate or efficiency of growth. Addition of the combination of isoleucine and valine to the 11% diet resulted in an increase (P less than .05) in both growth rate and feed efficiency to a level not different (P greater than .20) from that of the pigs consuming the positive control diet. The addition of valine to the 11% crude protein diet with supplemental lysine, tryptophan and threonine (Exp. 3) caused an improvement in daily gain (P less than .05) but not feed efficiency (P greater than .10). Isoleucine addition tended to reduce pig performance. The results of these experiments suggest that an 11% crude protein, corn-soybean meal diet fortified with lysine, tryptophan and threonine is not limiting in sulfur amino acids or nitrogen. Valine may be the only limiting amino acid. 相似文献
5.
Growth trials with starter (n = 120, 6.8 kg initially, 28 d of age, Exp. 1) and finisher (n = 70, 59 kg initially, Exp. 2) pigs were conducted to compare quality protein maize (QPM, .40% lysine) and normal corn (.31% lysine) in simple corn-based diets containing the same levels of soybean meal. In Exp. 1, pig performance was similar (P greater than .10) on all diets, regardless of the level of soybean meal, suggesting that QPM and normal corn have similar feeding value in lysine-adequate (.99 to 1.11%) diets. In Exp. 2, less soybean meal was needed in QPM than in normal corn diets to maximize performance; increasing soybean meal from 10.8 to 13.8% improved rate (P less than .05) and efficiency (P less than .01) of gain of pigs fed normal corn diets but had no effect on performance of pigs fed QPM diets. A QPM-based diet containing 6% soybean meal and supplemental lysine and tryptophan failed to maximize feed efficiency, but growth rate was equal to that obtained on the normal corn diet with 13.8% soybean meal. The apparent fecal digestibility of GE and ileal digestibility of N were similar for QPM and normal corn, but apparent ileal digestibility of most essential amino acids was slightly higher for QPM (Exp. 3). Experiment 4 compared apparent digestibilities of QPM, conventional opaque-2 corn and two high-protein corns. Digestibilities differed (P less than .05) among the corns, but the absolute differences were small and were likely due to differences in amino acid content of the corns.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Anderson LP Paterson JA Ansotegui RP Cecava M Schmutz W 《Journal of animal science》2001,79(8):2224-2232
Two 60-d experiments were conducted to evaluate the effects of supplementing degradable (DIP) and(or) undegradable (UIP) intake protein on the performance of lactating first-calf heifers. Diets were formulated to meet the requirements for either DIP, metabolizable protein (MP), or both when diets contained low-quality grass hay and an efficiency of microbial protein synthesis estimate of 10%. In Exp. 1, 32 individually fed first-calf heifers (avg 395 kg) were allotted to a 2 x 2 factorial arrangement of treatments (main effects of DIP, MP, and DIP x MP interaction) 1 d after calving. Cows consumed a basal diet of chopped crested wheat grass hay (4.3% CP, 67% DIP) ad libitum. Supplemental DIP and UIP were supplied by varying the ratios of soybean meal (75% DIP) and a heat-treated, protected soybean meal (70% UIP). Cow weight gain was better (P < 0.01) when adequate DIP was supplied than when DIP was deficient. However, calf weight gain was not increased by supplementing the cow with DIP. Supplemental UIP did not (P > 0.40) improve cow or calf weight gain. Blood urea N levels were higher (P < 0.01) for cows receiving supplemental DIP and UIP. However, milk production estimates were similar among treatments, as were digestibilities of OM and ADF. Nitrogen digestibility was greater when supplemental DIP was fed, but providing additional UIP did not (P = 0.15) change N digestibilities. Experiment 2 evaluated similar supplements using the same experimental design to determine changes in cow and calf weight gain, body condition score, and pregnancy rate. Seventy-two first-calf heifers (avg 441 kg) were allotted to supplement treatments 1 d after calving and were fed grass hay (5% CP, 53% DIP, 10% microbial efficiency) for ad libitum consumption for 60 d. Supplements were individually fed three times/week. Varying the ratios of soybean meal, heat-treated soybean meal, and corn gluten meal provided additional DIP and UIP. Unlike in Exp. 1, supplemental UIP improved (P < 0.05) cow weight gain. Calves from dams supplemented with DIP gained 5 kg more weight after 60 d than calves from dams deficient in DIP. Pregnancy rates in the fall were similar (P = 0.90) among treatments. These data suggest that DIP was more limiting in Exp. 1 than was UIP. Supplementing UIP in Exp. 2 improved cow weight gains but did not improve calf gains. Data suggest that the efficiency of microbial protein synthesis for this forage-based diet was probably less than 10%. 相似文献
7.
1. Two experiments were carried out to determine the response of broiler chicks to threonine‐supplemented diets between 10 and 28 d and 7 and 21 d of age, respectively.
2. In the first experiment female broiler chicks were fed on 11 experimental diets. Two iso‐energetic basal diets (diets 1 and 2) were prepared with 200 and 160 g CP/kg and 7·6 and 6·0 g threonine/kg respectively. Both diets contained 11·5 g lysine and 8·7 g sulphur‐containing amino acids/kg. Diet 3 was composed of diet 2, supplemented with all essential and non‐essential amino acids (EAA and NEAA, respectively) except threonine, to the concentrations of the amino acids in diet 1. The NEAA were added as a combination of glutamic acid and glycine. Diets 4 to 11 had the same compositions as diet 3, but contained increasing amounts of threonine.
3. For birds fed on diet 2, gain was significantly lower and food/gain ratio was significantly higher than for birds fed on diet 1. Supplementation with EAA, NEAA and threonine to the same concentrations in diet 1 resulted in a performance similar to that found on diet 1.
4. In experiment 2, male and female broiler chicks both received 10 experimental diets. Diet 1 contained 220 g CP/kg and 8.5 g threonine/kg, diet 2 contained 160 g CP/kg from natural raw materials and 6 g threonine/kg. Both diets contained 12·4 g lysine and 9·3 g sulphur‐containing amino acids/kg. Basal diet 2 was supplemented with all EAA and NEAA to the concentrations of basal diet 1, except for threonine. Diets 3 to 10 had the same compositions as the supplemented diet 2, but contained increasing amounts of threonine.
5. For male and female chicks on diet 2, gain was significantly lower and food/gain ratio significantly higher than those on diet 1. Diet 10 (160 g CP/kg plus all EAA, including threonine, and NEAA supplemented to the concentrations of diet 1) resulted in the same performance as diet 1.
6. The results indicate that, when low protein maize‐soyabean meal diets supplemented with EAA and NEAA with 13·31 MJ ME/kg were fed to male and female broiler chicks until 21 d of age, improvements in gain and food/gain ratio were obtained when the dietary threonine content was increased to 7·25 g/kg. When female chicks were fed threonine‐supplemented diets to 28 d of age, improvement in gain and food/gain ratio was obtained when the threonine concentrations were increased to 6·32 g/kg diet.
7. Curves have been fitted to the data, from which a cost‐benefit analyses can be made and an optimum threonine dose calculated, using local prices. 相似文献
8.
《The Journal of Applied Poultry Research》2009,18(2):292-296
An experiment was conducted to study the effect of different protein meals, with or without enzyme supplementation, on the performance of broilers. A diet based on a combination of protein meals (15% soybean meal, and 5% each of sunflower meal, canola meal, rapeseed meal, and cottonseed meal) was compared with 4 other diets containing 15% soybean meal and 20% of sunflower meal, canola meal, rapeseed meal, or cottonseed meal. Experimental diets were formulated to contain 2,630 kcal of ME/kg and 0.95% digestible lysine, with all other essential amino acids set to meet or exceed the ideal protein ratios. Each diet was fed with or without supplemental exogenous enzyme (Rovabio Excel at 500 g/metric ton of feed) to 6 replicate pens of 50 chicks from 1 to 35 d posthatch as coarse mash. In the cottonseed meal-based diet, supplemental enzyme resulted in high 35-d feed intake and FCR compared with the cottonseed meal-fed groups with no enzyme. There was a significant (P < 0.05) diet × enzyme interaction for 35-d feed intake and FCR. Birds fed the sunflower meal-based diet had significantly (P < 0.05) higher final BW gain and lower FCR as compared with those fed rapeseed meal- or cottonseed meal-based diets, whereas the BW gain of birds fed the rapeseed meal-based diet was significantly (P < 0.05) reduced compared with birds in all other groups. In conclusion, in low-ME broiler diets formulated on a digestible amino acid basis, up to 20% sunflower meal and canola meal can be safely incorporated into the diet. Supplementation of Rovabio failed to exert any positive effect on production parameters when used with diets containing high levels of each of the common protein meals. 相似文献
9.
豆粕和棉粕日粮中添加α-半乳糖苷酶对肉仔鸡生长性能的影响 总被引：2，自引：0，他引：2
试验研究了豆粕日粮和含5%～8%棉粕的日粮中添加α-半乳糖苷酶对肉仔鸡生长性能的影响及可能机制。试验Ⅰ为肉仔鸡饲养试验,选用1日龄AA商品代肉仔鸡公雏672只,随机分为4个处理,每个处理12个重复,每个重复14只鸡,试验期42d。结果表明:在棉粕和豆粕日粮中添加α-半乳糖苷酶对42日龄肉仔鸡体增重分别提高了4.35%和3.49%。试验Ⅱ为排空强饲代谢试验。结果显示:豆粕日粮中添加α-半乳糖苷酶增加蛋公鸡色氨酸真消化率(P<0.001),对其他氨基酸消化率无影响。添加α-半乳糖苷酶的豆粕的,真代谢能值与不添加酶的相比,提高了4.69%(0.51MJ/kg)。本研究表明,在玉米-豆粕型日粮中添加α-半乳糖苷酶,提高了色氨酸真消化率和真代谢能,有利于提高肉仔鸡生长性能。 相似文献
10.
《The Journal of Applied Poultry Research》2004,13(4):628-638
Two experiments were conducted with Ross × Ross broiler chicks in battery brooders from 7 to 21 d of age to determine the Arg and Met requirements of young broiler chicks at control (25°C) and warm (35°C) temperatures. In both experiments, 1-d-old broiler chicks were fed a corn and soybean meal based starter diet for 7 d. Six replications (2 replicates in each of 3 rooms per temperature) with 8 chicks each were used for each treatment. In experiment 1, the basal diet was based on corn (34.52%), whey (26.96%), corn gluten meal (16.53%), soybean meal (11.74%), and poultry fat (23% of CP and 3.20 kcal/g of MEn). Six levels of Arg (0, 0.1, 0.2, 0.3, 0.4, and 0.5%), supplementing the basal diet containing 0.95% Arg, were the dietary treatments. A broken-line linear model was used to estimate chick Arg requirements. Based on body gain and feed conversion ratio (FCR) data, respectively, the Arg requirements of young Ross × Ross broiler chicks raised at 35°C were 1.15 ± 0.03% and 1.13 ± 0.02%, whereas those of chicks at 25°C were 1.26 ± 0.03% and 1.27 ± 0.02%. In experiment 2, the influences of temperature and dietary Arg on the Met requirements of young broiler chicks were investigated. The basal diet was based on corn (53.45%), soybean meal (37.72%), and poultry fat (23% of CP and 3.20 kcal/g of ME). Experiment 2 had a 6 × 2 factorial arrangement, with the basal diet (0.35% Met and 1.52% Arg) supplemented with 6 levels of dietary Met (0, 0.05, 0.1, 0.15, 0.2, or 0.3%) and 2 levels of dietary Arg (0 and 1.0%). When chicks were fed a corn-soybean meal basal diet containing 1.52% Arg, the Met requirements of young Ross × Ross broiler chicks raised at 35°C were 0.43 ± 0.02% and 0.43 ± 0.03%, whereas those of chicks at 25°C was 0.43 ± 0.01% and 0.48 ± 0.03%, based on body gain and FCR data, respectively. When Arg levels were increased to 2.52%, the Met requirement of young Ross × Ross broiler chicks was greater at both temperatures (P < 0.05). The requirements of chicks raised at 35°C were 0.50 ± 0.02% and 0.49 ± 0.02% and at 25°C were 0.59 ± 0.03% and 0.57 ± 0.02%, based on body gain and FCR data, respectively. Temperature and amino acid balance may both affect the amino acid requirements of broilers. 相似文献
11.
Zinc bioavailability in soybean meal 总被引：2，自引：0，他引：2
A phytate-containing soy protein concentrate (SPC) diet (13.5 mg Zn/kg) and a phytate-free egg white diet (.3 mg Zn/kg) were used to determine the relative bioavailability (RBV) of Zn in dehulled soybean meal (SBM) based on Zn depletion-repletion growth bioassays in young chicks. After a 4-d Zn depletion period, chick weight gain responded linearly (P < .01) to graded increments of supplemental Zn (0 to 10 mg/kg) from ZnSO4 x 7H2O, whether added to the Zn-deficient SPC or egg white diet. Slope, however, was over twice as great for the standard curve relating weight gain to supplemental Zn intake for the egg white diet as for the SPC diet. Addition of 7 to 10 mg Zn/kg from SBM to either Zn-deficient diet increased (P < .01) weight gain, but a similar SBM addition to either diet made adequate in Zn did not increase weight gain. Using standard-curve methodology, RBV of Zn in SBM was 78% when the the SPC diet was used, but it was only 40% when the egg white diet was used. The phytate contained in the SPC basal diet therefore markedly reduced the efficiency of utilizing the supplemental inorganic Zn from ZnSO4 x 7H2O. This lowered the slope of the standard curve so that, on a relative basis, the Zn in SBM had a higher RBV value than was the case for Zn utilization in SBM with the phytate-free egg white diet. The 78% Zn RBV value in SBM would seem to have the greatest relevance for practical-type corn-SBM diets. 相似文献
12.
Figueroa JL Lewis AJ Miller PS Fischer RL Diedrichsen RM 《Journal of animal science》2003,81(6):1529-1537
Three experiments were conducted to determine the fifth-limiting amino acid for growing pigs in an 11% CP, corn-soybean meal diet. In each experiment, 36 gilts (initial weight 19.5, 21.9, and 21.0 kg, respectively) were penned individually and fed one of six diets in a randomized block design for 35 d. Diets containing 16, 12, and 11% CP were fed in each experiment. All 12 and 11% CP diets were supplemented with lysine, tryptophan, threonine, and methionine to provide the same total concentrations as those in the 16% CP diet. In Exp. 1, the 11% CP diet was supplemented with isoleucine, valine, or isoleucine + valine to concentrations equal to those in the 16% CP diet. In Exp. 2, the 11% CP diet was supplemented with histidine, histidine + valine, or histidine + isoleucine + valine. In Exp. 3, the 11% CP diet was supplemented with valine, histidine + valine, or isoleucine + valine. Gilts were allowed free access to feed and water. In all experiments, ADG and feed efficiency (G/F) were reduced (P < or = 0.07) as dietary protein was reduced. Supplementation of isoleucine alone further reduced (P < 0.05) ADG, ADFI, G/F, and fat-free lean gain. In contrast, supplementation of valine alone resulted in numerical increases in ADG and ADFI in two experiments, although the differences were not significant (P > 0.05). Supplementation with histidine and valine together resulted in growth performance equal to or greater than that of pigs fed the 12% CP diet, but less than that of pigs fed the 16% CP diet. Supplementation of isoleucine and valine together resulted in better growth performance (P < 0.05) than supplementation of either amino acid alone. In two experiments (Exp. 1 and 3), supplementation of the 11% CP diet with isoleucine and valine together resulted in ADG that were not significantly different (P > 0.05) from those of pigs fed the 16% CP diet. Supplementation of all three amino acids (Exp. 2) did not improve performance over supplementations with histidine and valine. Plasma urea concentrations were reduced (P < 0.05) as dietary protein was lowered from 16 to 12%. Additions of crystalline amino acids did not affect plasma urea levels. Plasma amino acid concentrations reflected the dietary additions of crystalline amino acids, but did not assist in the identification of the sequence of limiting amino acids. These data suggest that valine is the fifth-limiting amino acid and that either histidine or isoleucine is the sixth-limiting amino acid in an 11% CP diet. 相似文献
13.
Threonine requirement for reproduction in swine 总被引：1，自引：0，他引：1
An experiment was conducted to estimate the threonine requirement of pregnant swine. L-threonine was added to a fortified corn-gelatin diet and fed at a rate to provide five threonine levels of 3.59, 4.95, 6.31, 7.67 and 9.03 g/d. Twenty-five crossbred gilts were randomly assigned to these five dietary treatments. Increasing threonine resulted in a difference (P less than .01) in nitrogen (N) retention, with maximum retention at 4.95 g/d threonine intake. Blood samples were drawn before and after feeding. Although plasma urea N did not change significantly, the lowest level occurred at an intake of 4.95 g/d threonine. As threonine intake increased, plasma threonine increased quadratically (P less than .05). This increase was accompanied by a quadratic (P less than .005) decrease in plasma lysine. Sow weight gains increased quadratically (P less than .01) with increasing threonine levels. Litter weight, number of pigs born, baby pig gains, daily milk yield and milk protein were not influenced by threonine levels. The lysine-alpha-ketoglutarate reductase activity of the sow liver samples increased linearly (P less than .05) as dietary threonine levels increased. Based upon metabolic criteria 4.95 g/d L-threonine met the requirement for animals in this experiment. If 75% of threonine in a corn-soybean meal diet is available, the threonine requirement for reproduction would be no higher than 5.4 g/d or .30% dietary threonine when daily feed intake is 1.82 kg. 相似文献
14.
A fattening trial was carried out with 8 groups of broilers each comprising 1225 birds. Within this trial tests were made to replace the protein feeds of newly hatched chicks over a period of up to 56 days of age, by wheat rich in crude protein. If wheat with a high crude protein content is fed supplementation with lysine and methionine will be necessary depending on the kind of protein feed used. No supplementation with amino acids is required if rations of fish meal + extracted soya bean meal are used despite their reduced content of these amino acids. The broilers consumed larger quantities of the wheat + extracted soya bean meal+fish meal ration than of the mixtures containing no fish meal. Food requirements per unit of weight gain were the same for the mixtures containing high-protein wheat and for the standard maize ration. The lowest food consumption per unit of weight gain was computed for the wheat + extracted soya bean meal diet supplemented with amino acids. The same quantities of lysine, thioamino acids and threonine were necessary for broilers receiving the wheat rations as for birds of the standard group. Protein feed may be saved by using high-protein wheat in the fattening of broilers. The rates of weight gain obtained with these rations are the same or even better than those achieved with rations of maize + fish meal+soya bean meal. 相似文献
15.
144头75日龄小猪随机分成3个处理组,每组设4个重复。1组为对照日粮组;2组别为对照日粮+300g/tα-半乳糖苷酶;3组别为对照日粮+500g/tα-半乳糖苷酶,此外,2组和3组的日粮在配方设计时,将豆粕的代谢能和氨基酸参数分别提高7%和5%,营养水平的计算值与1组相同。2组和3组的日粮配方成本比1组分别低41和25元/t(已扣除酶制剂使用成本)。通过连续40d(75～115日龄)的饲喂,结果表明,在3个组别之间,"增重"和"平均日增重"都没有显著的差异,而对照日粮组的"耗料量"略高于2组和3组。添加500g/tα-半乳糖苷酶的3组,其"料肉比"显著低于对照组;添加α-半乳糖苷酶的2组和3组每千克增重成本分别降低0.15和0.55元。因此,α-半乳糖苷酶在配方中的添加使用可以在不影响动物生长性能的前提下显著降低饲料的配方成本和养殖成本。 相似文献
16.
Tryptophan and threonine requirements of young pigs and their effects on serum calcium, phosphorus and zinc concentrations 总被引：8，自引：0，他引：8
Four 28-d trials were conducted using a total of 432 pigs, with average initial weight across trials ranging from 6.3 to 9.7 kg, to estimate the tryptophan (trials 1 and 2) and threonine (trials 3 and 4) requirements of pigs fed low protein, corn-sunflower meal diets. The effect of tryptophan, threonine and protein level on serum calcium, phosphorus and zinc also was studied. The diets contained either 12 or 13% protein and were calculated to be adequate in all nutrients except crude protein and the amino acid being investigated. A lysine supplemented, 18% protein, corn-sunflower meal diet was included in all trials as a positive control. In trial 1, weight gains of pigs increased linearly (P less than .005) while feed conversion improved cubically (P less than .05) as dietary tryptophan increased from .14 to .22%. Pigs fed the 18% protein diet gained faster (P less than .05) and required less feed/gain than pigs fed low protein diets. In trial 2, weight gains improved quadratically (P less than .005) and feed conversion improved linearly (P less than .05) as dietary tryptophan increased from .104 to .204%. Serum phosphorus and zinc concentrations were lower (P less than .05) in pigs fed the 18% protein diet. In both trials, serum urea N responded quadratically (P less than .05) to increasing dietary tryptophan, and was lower (P less than .05) in pigs that were fed diets supplemented with L-tryptophan than in those fed the low protein basal or 18% protein diets.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
A trial was conducted to examine the potential of using plasma amino acid responses to graded levels of escape protein to determine limiting amino acids in cattle. Growing calves (n = 120; mean BW = 220 +/- 21 kg) were fed a basal diet of corncob:sorghum silage (61:39) and were individually supplemented with distillers' dried grains (DDG), heat-damaged DDG (H-DDG), feather meal (FTH), or urea. The urea supplement was mixed with DDG and H-DDG to allow 0, 20, 35, 50, 65, or 80% of the supplemental CP to come from distillers' protein and maintain an 11.5% CP diet. Urea supplement was mixed with FTH to allow 0, 22, 39, 56, 73, or 90% of the supplemental CP to come from FTH. Dietary CP ranged from 11.5% at the 0% level to 17.3% at the 90% level. Plasma concentration of most essential plasma amino acids responded (P less than .10) linearly and(or) quadratically to increased escape protein. The broken-line response of plasma methionine at low DDG intake suggested that methionine was limiting at low levels of escape protein. An initial decrease followed by a plateau fit by a broken line indicated that histidine became limiting in FTH diets, and lysine eventually became limiting for DDG, H-DDG, and FTH diets before maximum BW gain was reached. Results indicate that plasma amino acid responses may identify amino acids that become limiting with increasing escape protein. 相似文献
18.
Laura Greiner Pairat Srichana James L.Usry Casey Neill Gary L.Allee Joseph Connor Kevin J.Touchette Christopher D.Knight 《畜牧与生物技术杂志(英文版)》2018,(2)
Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments(Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.Results: Exp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance.Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075,0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68,2.73, 2.67, 2.70, and 2.64 kg/d(P 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine,respectively. No other differences among dietary treatments were observed.Conclusions: Collectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born. 相似文献
19.
Two experiments were conducted on growing male SPF-rats to compare weight gain, feed conversion efficiency and plasma free lysine concentration as response criteria in evaluating adequacy of lysine plus threonine and lysine plus tryptophan supplements to the deficient diets. Two basal semisynthetic diets were prepared limiting in lysine and threonine (Expt. 1) and lysine and tryptophan (Expt. 2). The addition of graded supplements to the basal diets of L-lysine X HCl alone (0.2; 0.4; 0.6; 0.8 and 1.0% of diet) induced imbalance of amino acids resulting in low level of daily weight gain and feed conversion efficiency. Plasma free lysine concentration started to grow linearly from the first supplement of L-lysine X HCl. If rats were fed the diets containing identical supplements of L-lysine X HCl in combination with two supplements of L-threonine (0.2 and 0.4% of diet, Expt. 1) or L-tryptophan (0.05 and 0.1% of diet, Expt. 2), plasma free lysine started to increase before supplements of amino acids were adequate to support maximum weight gain and feed conversion efficiency. this difference in response seems to be caused by different feeding regiment during the growth period of the experiments (ad libitum) and training period prior to blood sampling (feeding twice daily). 相似文献
20.
Ileal amino acid digestibility and performance of growing pigs fed wheat-based diets supplemented with xylanase 总被引：7，自引：0，他引：7
Barrera M Cervantes M Sauer WC Araiza AB Torrentera N Cervantes M 《Journal of animal science》2004,82(7):1997-2003
Two experiments were conducted to determine the effect of supplementation of xylanase to a wheat-based diet on the apparent ileal digestibility (AID) of AA and the performance of growing pigs fed diets limiting in AA. In Exp. 1, eight pigs (average initial BW = 20.5+/-1.2 kg) fitted with a simple T-cannula at the distal ileum, were fed four diets according to a repeated 4 x 4 Latin square design. Diet 1 was a basal diet that contained 97.6% wheat. Diets 2, 3, and 4 were the basal diet supplemented with xylanase at rates of 5,500, 11,000, and 16,500 units of xylanase activity (XU), respectively (as-fed basis). There were linear and quadratic effects (0.062 < P < 0.001) of xylanase supplementation on the AID of CP and most of the AA. The largest increases in AID of CP and AA were obtained when xylanase was supplemented at a rate of 11,000 XU; no further increases were observed with xylanase supplementation at a rate of 16,500 XU. In Exp. 2, 30 pigs (average initial BW 21.4+/-1.8 kg) were randomly allotted to six dietary treatments. Diets 1 to 4 were similar to those used in Exp. 1. Diet 5 was the same as Diet 1, but supplemented with 0.53% lysine, 0.12% threonine, and 0.05% methionine. Diet 6 (positive control diet) was a wheat-soybean meal diet that contained 18.2% CP (as-fed basis). The total contents of lysine, threonine, and methionine were similar for Diets 5 and 6. There was a linear effect of xylanase supplementation on ADG (P = 0.093) and feed:gain ratio (P = 0.089), and a quadratic effect on ADG (P = 0.067) and feed:gain ratio (P = 0.074). But, the greatest response was obtained with the supplementation of 11,000 XU. The supplementation of lysine, threonine, and methionine to Diet 1 increased (P = 0.001) ADG and ADFI and improved (P = 0.01) feed:gain ratio. There was no difference (P = 0.508) in the performance of pigs fed the AA-supplemented or control diet. In conclusion, the supplementation of xylanase to a diet in which wheat provided the sole source of protein and energy improved the AID of AA, ADG, and feed:gain ratio; however, this improvement was very small compared with that obtained with the supplementation of synthetic amino acids. 相似文献