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1.
An experiment using 96 Hy‐Line brown laying hens at 29 weeks of age that were randomly allocated to four treatments with eight replicates was conducted to assess the effects of star anise (Illicium verum Hook.f.) oil (SAO) on nutrient and energy utilization. Dietary treatments were corn–soybean meal‐based diets supplemented with 0, 200, 400, and 600 mg/kg SAO. The birds were fed the diets for 14 days. The conventional nutrients and amino acids of feed and excreta samples were measured for calculating apparent metabolic efficiency, and gross energy (GE) was analyzed for computation of apparent metabolic energy (AME) and true metabolic energy (TME). Endogenous losses were obtained from another 16 birds for calculating true metabolic efficiency. Birds supplemented with SAO had higher (p < 0.05) metabolic efficiency of crude protein (CP), organic matter (OM), Lys, Met, Arg, and Thr than those of control group. Quadratic effects on utilization of Lys, Met, and Thr were observed (p < 0.05). Inclusion of SAO to diet improved nutrient utilization, and the efficacy is best at 400 mg/kg.  相似文献   

2.
本试验旨在研究在2种能量水平饲粮中添加大豆卵磷脂乳化剂对肉鸡生长性能、养分利用率和血清生化指标的影响。试验采用2×2因子完全随机区组试验设计,将960只1日龄科宝500白羽肉公鸡随机分为4组,每组6个重复,每个重复40只鸡。各组试验鸡分别饲喂2个能量水平和2个乳化剂添加水平组成的试验饲粮,其中代谢能分别为12.13和11.92 MJ/kg(1～21日龄)、12.96和12.65 MJ/kg(22～49日龄),乳化剂添加水平分别为0和265 mg/kg(1～21日龄)、0和400 mg/kg(22～49日龄)。试验测定肉鸡生长性能,能量、干物质、粗蛋白质和粗脂肪表观利用率,以及血糖、血脂和胆汁酸含量。结果表明:肉鸡采食正常能量饲粮前期(1～21日龄)平均日增重极显著高于低能量饲粮(P<0.01),肉鸡全期(1～49日龄)采食添加乳化剂的低能量饲粮料重比能达到正常能量饲粮水平;饲粮添加乳化剂有提高平均日增重和饲粮粗脂肪和能量表观利用率的趋势,可促进胆汁分泌,能显著降低前期及全期料重比(P<0.05)。结果显示,降低饲粮能量显著降低1～21日龄肉鸡平均日增重,提高1～21日龄和1～49日龄料重比;饲粮添加乳化剂能够改善饲料利用率,特别是在1～21日龄肉鸡低能量饲粮中效果更明显。  相似文献   

3.
Growth, apparent nutrient digestibility, ileal digesta viscosity, and energy metabolizability of growing turkeys fed diets containing malted sorghum sprouts (MSP) supplemented with enzyme or yeast were investigated using 120, 28‐day‐old male turkeys. Six treatments were laid out in a 3 × 2 factorial arrangement of treatments with three dietary inclusion levels of MSP (0, 50, and 100 g/kg) and supplemented with 200 mg/kg yeast (Saccharomyces cerevisiae) or 200 mg/kg of a commercial enzyme. The experiment lasted for the starter (day 28–56) and grower phases (day 57–84) of the birds. Each treatment group consisted of 20 turkeys replicated four times with five birds each. Data were analysed using analysis of variance while polynomial contrast was used to determine the trends (linear and quadratic) of MSP inclusion levels. Irrespective of dietary supplementation with enzyme or yeast, final body weight (BW), total BW gain, and feed intake for turkey poults from day 29–56 was reduced (p < 0.05) with increasing inclusion level of MSP. Dietary supplementation with yeast resulted in increased (p < 0.05) feed intake while enzyme supplementation improved (p < 0.05) feed conversion ratio of the poults. Turkeys fed enzyme‐supplemented MSP diets had higher (p < 0.05) BW gain than their counterparts fed yeast‐supplemented MSP diets. Apparent ash digestibility reduced linearly (p < 0.05) with increasing inclusion levels of MSP. Apparent metabolizable energy (AME) did not vary significantly (p > 0.05) with MSP inclusion levels . Enzyme supplementation reduced (p < 0.05) ileal viscosity but had no effect (p > 0.05) on AME. Inclusion of MSP resulted in poor growth performance. This confirms earlier studies that utilization of MSP by poultry is rather poor. Supplementation with enzyme or yeast did not lead to any appreciable improvement in performance of turkeys in this study.  相似文献   

4.
ABSTRACT

1. The influence of barley inclusion level and supplementation of a multi-component non-starch polysaccharide degrading enzyme on performance and nutrient utilisation in broilers was investigated. Normal-starch hulled barley was evaluated with five levels of inclusion (0, 141, 283, 424 and 565 g/kg) in a wheat-based diet and two levels of enzyme supplementation (0 and 150 g/tonne of feed; a 5 × 2 factorial arrangement of 10 dietary treatments). All diets were equivalent in metabolisable energy and digestible amino acid contents. A total of 400, one-d old male broilers (five cages/treatment; eight birds/cage) were used in the experiment.

2. Regardless of enzyme supplementation, weight gain (WG) increased up to 283 g/kg of barley and was reduced afterwards (P < 0.01). Increasing levels of barley resulted in greater (P < 0.001) gain per feed (G/F). Enzyme addition increased WG (P < 0.05) and G/F (P < 0.001) at each barley inclusion level.

3. Birds fed diets with 0 and 565 g/kg barley showed the lowest and highest (P < 0.001to 0.05) digestibility for all nutrients measured, respectively. Digestibility of all nutrients was improved by enzyme supplementation at each barley inclusion level (P < 0.05). The nitrogen-corrected apparent metabolisable energy improved with increasing inclusion of barley (P < 0.001) and supplemental enzyme (P < 0.01). Increasing inclusion of barley increased the relative weight of gizzard (P < 0.001) and reduced jejunal digesta viscosity (P < 0.001). Supplemental enzyme (P < 0.001) reduced digesta viscosity.

4. The optimum inclusion level of barley, with respect to growth performance, was 283 g/kg of diet. Increasing barley inclusion improved nutrient and energy utilisation, possibly through lowered digesta viscosity and better function of the gizzard. Feed efficiency and nutrient and energy utilisation can benefit from carbohydrase supplementation in barley-based diets, regardless of barley inclusion level.  相似文献   

5.
Eighteen Chinese Holstein heifers average age 230 ± 14 days were allocated to 1 of 3 dietary crude protein (CP) to metabolizable energy (ME) ratios to examine the effects on growth performance, blood metabolites and rumen fermentation parameters with 90‐days experiment. Three different dietary CP:ME ratios were targeted based on the formulation of dietary CP contents of 10.85%, 12.78% and 14.63% on dry matter (DM) basis with similar ME contents (10.42 MJ/kg DM), which were categorized as low, medium and high dietary CP:ME ratios. The actual CP:ME ratios obtained in this study significantly increased from low to high CP:ME ratio groups with a value of 10.59, 11.83 and 13.38 g/MJ respectively. Elevated CP:ME ratios significantly increased CP intake (kg/day) and feed efficiency (FE) which was defined as dry matter intake as a proportion of average daily gain (ADG), whereas little difference was observed in body weight (kg), ADG (kg/day), DM intake (kg/day) and ME intake (MJ/day) among the three different CP:ME ratio groups. Increasing dietary CP to ME ratios significantly increased CP digestibility, whereas digestibility of DM and gross energy remained constant in the current experiment. Blood urea nitrogen and insulin‐like growth factor‐1 linearly increased with increasing dietary CP:ME ratios. There was significantly dietary treatment effect on rumen fermentation parameters including acetate, propionate, butyrate and total volatile fatty acids. Therefore, this study indicated that increasing dietary CP levels with similar energy content contributed to increased protein intake and its digestibility, as well as FE. Holstein heifers between 200 and 341 kg subjected to 13.38 dietary CP:ME ratio showed improved feed efficiency, nutrient digestibility, some blood metabolites and rumen fermentation characteristics for 0.90 kg/day rate of gain.  相似文献   

6.
This study investigated the influence of pre‐pelleting inclusion of whole wheat (WW) and exogenous enzyme supplementation on growth performance, coefficient of apparent ileal nutrient digestibility (CAID) and apparent metabolizable energy (AME) in broilers fed wheat‐based pelleted diets. A 2 × 3 factorial arrangement of treatments was used with two methods of wheat inclusion [622 g/kg ground wheat (GW) and 250 g/kg WW replaced GW (wt/wt) pre‐pelleting (PWW)] and three enzymes (xylanase, phytase and xylanase plus phytase). A total of 288, one‐day‐old male broilers (Ross 308) were individually weighed and allocated to 36 cages (8 broilers/cage), and the cages were randomly assigned to the six dietary treatments. Birds fed PWW diets gained more (p < 0.05) weight than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on feed intake (FI). Phytase alone increased (p < 0.05) FI compared to xylanase or the combination. Whole wheat inclusion increased (p < 0.05) the gain‐to‐feed ratio (G:F). Feeding xylanase plus phytase and phytase‐added diets resulted in the greatest and lowest G:F, respectively, with xylanase supplemented diets being intermediate. Birds fed PWW diets had greater (p < 0.05) relative gizzard weights than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on the CAID of nitrogen (N), starch and fat. Combination of xylanase and phytase resulted in greater (p < 0.05) digestibility of N, starch and fat than that of individual additions. Feeding PWW diets resulted in greater (p < 0.05) AME values than GW diets. Combination of xylanase and phytase increased (p < 0.05) the AME compared to the diets with individual additions of xylanase or phytase. The current results suggest that the influence of pre‐pelleting WW inclusion and exogenous enzymes on nutrient digestibility and broiler performance is not additive.  相似文献   

7.
The effects of dietary supplementation of zinc (Zn) sources and concentrations were investigated on growth performance, absorption into tissues, fecal excretion, nutrient retention, and intestinal morphology in broilers fed a corn-soybean meal basal diet. A total of 525 one-day-old chicks (Ross 308) were assigned based on body weight to seven dietary treatments. There were five replicate pens for each treatment and 15 broilers per replicate pen. The dietary treatments included a basal diet (control, without supplementing Zn), and basal diet supplemented with Zn, as inorganic zinc sulfate (ZnS; 110 mg/kg); organic Zn-methionine (ZnM; 110 mg/kg); hot-melt extruded (HME) 25 zinc sulfate (27.5 mg/kg); HME50 zinc sulfate (55 mg/kg); HME75 zinc sulfate (82.5 mg/kg); or HME100 zinc sulfate (110 mg/kg) for 35 days in two phases (d 1–21, phase I and d 22–35, phase II). Bodyweight and feed efficiency of broiler chicks fed diets supplemented with increasing dietary concentrations of HME-Zn improved linearly during the study period (P<0.05). Compared to the control treatment, the ZnS, ZnM, and HME diets increased Zn concentrations in the serum and liver. Inorganic ZnS supply resulted in the highest Zn concentration in excreta. Increasing supplemented Zn content in diets as HME linearly increased Zn concentration in the excreta, serum, liver, and tibia. Broiler chicks fed diets supplemented with increasing concentrations of HME increased villus height (VH; linear and quadratic) of the jejunum and VH of the ileum (linear). Increasing concentrations of dietary Zn supplied as HME resulted in linearly enhanced dry matter, gross energy, and nitrogen retention of broilers on day 21. These results suggest that dietary HME-Zn at a lower level (55 ppm) shows the same growth performance as common ZnSO4 at 110 ppm.  相似文献   

8.
1. Two experiments were conducted to investigate the effects of dietary chitosan on growth performance, energy availability and protein retention in broilers. 2. Experiment 1 was a 42-d growth assay, in which 294 1-d-old male broilers were given one of 7 dietary treatments. A control feed was supplemented with 5 levels of chitosan (0.2, 0.5, 1.0, 3.0 and 5.0 g/kg) or 50 mg/kg chlortetracycline (CTC). 3. Increasing chitosan inclusion gave a nonlinear increase (P< 0.001) in feed conversion efficiency (FCE). Optimal growth and feed conversion were obtained with 0.5-1.0 g/kg chitosan. 4. In experiment 2, 42 1-d-old male broilers (6/treatment) were individually housed but fed on the same diets as in experiment 1. Excreta were collected from d 19-21 and d 40-42. 5. The addition of 0.5-1.0 g/kg chitosan increased nitrogen retention compared with the control group (P< 0.01), while apparent metabolisable energy in the diets was not altered.  相似文献   

9.
A total of 3,240 female Taisheng pigeons at 40 wk age were fed 9 diets containing 3 ME levels (2,630, 2,770, and 2,940 kcal/kg) and 3 CP levels (14.0, 15.0, and 16.0%) in a factorial arrangement. These diets were fed to investigate the effects of ME and CP on performance, egg quality, and nutrient digestibility. Female pigeons were housed under the same managerial conditions and randomly assigned into 9 treatments (6 replicates of 60 birds each). Two female–female paired pigeons housed in one cage were under a 16L:8D lighting cycle. Feed in pellet form and water were provided for ad libitum consumption. The study lasted 12 wk. As dietary ME level increased from 2,630 to 2,940 kcal/kg, BW, egg production, and apparent DM, crude fat (CF), and phosphorus (i.e., P) digestibilities increased (P < 0.05), feed intake decreased (P < 0.05), and feed conversion efficiency increased (P < 0.05). Increasing the level of dietary protein from 14 to 16% resulted in an increased (P < 0.05) BW, shell percentage, length of the major axis, and DM digestibility. Therefore, dietary ME had a greater influence on the performance of Taisheng laying pigeons than did dietary protein.  相似文献   

10.
A 3 × 3 + 1 factorial, involving three levels of protease (0, 15,000 or 30,000 PROT/kg) and three levels of phytase (1,000, 2,000 or 3,000 FYT/kg), was used to evaluate the effect of replacing commercial soybean meal (SBM) with raw, full‐fat soybean (RFSB) at 75 g/kg of diet for broilers. A control diet was used for comparison. Each treatment was replicated six times, with nine birds per replicate. The concentration of trypsin inhibitors (TIs) in the test diets was approximately 10,193.4 TIU/kg. Regardless of enzyme supplementation, feed intake (FI) and body weight gain (BWG) of birds in the control group were superior to those on the test diets. Birds that received the protease‐free test diets had reduced FI and BWG, but when supplemented with protease, were similar to the control diet in BWG, FI (except 0–35 days) and feed conversion ratio (FCR). When the test diet was supplemented with elevated levels (extradose) of protease and phytase, the BWG was improved during 0–10 days (p = .05) and 0–24 days (p < .01). Regardless of protease supplementation, the weight of thighs was lower for birds fed the test diets. Birds that received the control diet had smaller weight of pancreas. Increasing the level of phytase supplementation reduced (p < .05) the weight of the pancreas. The apparent ileal digestibility (AID) of CP and AA was higher in birds on the control diets, but this was also improved in test diets by protease supplementation. The activities of trypsin (7%), general proteolytic (11%) and lipase (12%) were slightly increased because of protease supplementation. Mucosal depth and apparent villus surface areas were increased by about 2.9% and 20%, respectively, due to supplementation of elevated level of phytase. It can be concluded that RFSB could partially replace SBM in broiler diets, provided the diets are supplemented with elevated levels of protease and phytase.  相似文献   

11.

Fifteen Bhadawari buffalo heifers of 207?±?9.78 kg mean body weight were randomly distributed into three dietary groups to evaluate the effect of protein level on nutrient utilization, nitrogen (N) balance, growth rate, blood metabolites, and puberty. All animals were offered wheat straw-berseem diets supplemented with concentrate mixtures of similar energy (2.7 Mcal/kg) and different protein levels (14.3–22 %). Animals of standard-protein group (SPG) were offered protein and energy as per requirement, while animals of low-protein group (LPG) and high-protein group (HPG) were fed 20 % less and 20 % more protein, respectively, than SPG. Feed dry matter (DM) and metabolizable energy (ME) intake (% body wt. and g/kg w0.75) were similar for all three diets; however, the crude protein (CP) and digestible crude protein (DCP) intake on percent body weight and per kilogram metabolic weight was higher (P?<?0.05) in HPG than in SPG or LPG. Digestibility of CP, cellulose, and hemicellulose was higher (P?<?0.05) in HPG versus LPG. Fecal N excretion was similar, while urinary N excretion was highest (P?<?0.05) in HPG (74.83 g/day) compared with SPG (50.03 g/day) and LPG (47.88 g/day), which resulted in lower N retention in HPG than in the other dietary groups. Level of dietary N had no effect on blood metabolites viz. glucose, urea, and N. Digestible energy (DE) and ME contents of diets were identical, while DCP contents were higher (P?<?0.05) in HPG than in LPG. Feed and nutrient (CP and ME) conversion efficiency to produce a unit kilogram weight gain was identical among the dietary groups. Dietary protein level had no effect on the heifer’s weight and age at puberty. The mean growth rate of heifers at 240 days was higher (P?>?0.05) in SPG (330.8 g/day) than in LPG (296.7 g/day), while the animals gained more weight in January to March months and the lowest weight in May to July months. Protein level had no effect on conception rate of heifers. Results revealed that 20 % higher or less protein than the ICAR requirement had no significant (P?>?0.05) on feed intake, nutrient conversion efficiency for weight gain, heifer growth, and puberty; however, 20 % more protein increased urinary N loss.

  相似文献   

12.
本文旨在研究饲粮中添加不同水平的丝兰提取物(YSE)对肉仔鸡小肠黏膜形态、食糜消化酶活力和营养物质表观代谢率的影响,为确定YSE的适宜添加量提供理论依据。试验选取128只1日龄爱拔益加(AA)肉仔鸡,基础饲粮预饲14 d后随机分为4个组,每组4个重复,每个重复8只鸡,YSE添加水平分别为0(对照组)、100、200和300 mg/kg,试验期28 d。28和42日龄时每个重复随机选取2只肉仔鸡屠宰,取十二指肠、空肠和回肠的前段观察小肠黏膜形态,取食糜测定消化酶活力,35日龄时每个重复选取1只鸡进行代谢试验。结果表明:与对照组相比,1)饲粮中添加100 mg/kg YSE显著提高了肉仔鸡28日龄时空肠绒毛高度(VH)及42日龄时十二指肠VH和绒毛高度/隐窝深度(V/C)(P0.05)。2)饲粮中添加200 mg/kg YSE显著提高了肉仔鸡42日龄时回肠食糜胰蛋白酶(TRY)、脂肪酶(LPS)活力和十二指肠食糜LPS活力(P0.05)。3)饲粮中添加200 mg/kg YSE显著提高了肉仔鸡干物质(DM)和粗蛋白质(CP)表观代谢率(P0.05),而添加300 mg/kg YSE显著降低了CP表观代谢率(P0.05);100和200mg/kg YSE组钙(Ca)、磷(P)表观代谢率呈升高趋势而300 mg/kg YSE组呈降低趋势(0.05≤P0.10)。由此可见,从消化代谢功能看,YSE在肉仔鸡饲粮中的添加剂量以100~200 mg/kg为宜。  相似文献   

13.
Two hundred eighty-eight 1-d-old male Arbor Acres broilers were randomly allocated to 4 treatments to examine the effect of usingBacillus amyloliquefaciens-based direct-fed microbials (DFM) to replace antibiotics in the late growth stage on performance, nutrient digestibility, cecal microflora, and intestinal morphology in broilers. The experimental diets were (1) a negative control (NC) group fed a basal diet without any antibiotics; (2) a positive control (PC) group fed the basal diet with 200 mg/kg of zinc bacitracin; (3) a test group fed the basal diet with 200 mg/kg of zinc bacitracin from d 1 to 21 and 30 mg/kg of DFM from d 22 to 42 (DFM30); and (4) a test group fed the basal diet with 200 mg/kg of zinc bacitracin from d 1 to 21 and 60 mg/kg of DFM from d 22 to 42 (DFM60). The results showed that DFM30 and DFM60 increased BW gain and improved FCR as compared with NC group (P < 0.05). Generally, the PC, DFM30, and DFM60 groups showed increased apparent total tract nutrient digestibility for DM, CP, and AME as compared with the NC group. Both the DFM30 and DFM60 groups decreased cecalEscherichia coli population as compared with the NC group, and increased the population ofLactobacillus as compared with the PC group. The PC, DFM30, and DFM60 groups increased villus height and the ratio of villus height to crypt depth compared with NC. In conclusion, dietary supplementation withB. amyloliquefaciens-based DFM during d 22 to 42 may enhance performance by increasing nutrient digestibility and improving intestinal health in birds fed diets supplemented with zinc bacitracin from d 1 to 21.  相似文献   

14.
The objective of this study was to assess the effects of guanidinoacetic acid (GAA) on growth performance, creatine deposition and blood amino acid (AA) profile on broiler chickens. In Exp. 1, a total of 540 one‐day‐old Arbor Acres male broilers (average initial body weight, 45.23 ± 0.35 g) were divided randomly into five treatments with six replicates of 18 chicks each. Broilers were fed corn–soybean meal‐basal diets supplemented with 0, 600, 800, 1,000 or 1,200 mg/kg GAA for 42 days respectively. Results showed that dietary GAA inclusion increased average daily gain (ADG) and improved gain‐to‐feed ratio (G:F) from 1 to 42 days (p < 0.01). However, average daily feed intake was unaffected by dietary supplementation of GAA. As GAA inclusion increased, the contents of creatine in plasma and kidney were increased (linear, p < 0.01), while the contents of GAA and creatine in liver were decreased (linear, p < 0.01). Similarly, GAA supplementation was inversely related to concentrations of most essential AA in plasma. In Exp. 2, a total of 432 one‐day‐old Arbor Acres male broilers (average initial body weight, 39.78 ± 0.58 g) were divided randomly into four treatments with six replicates of 18 chicks each. Birds were fed a corn–soybean meal‐basal diet supplemented with 0, 200, 400 or 600 mg/kg GAA for 42 days respectively. Dietary inclusion of 600 mg/kg GAA significantly increased ADG and G:F of broilers (p < 0.05). In conclusion, dietary supplementation of 600–1,200 mg/kg GAA can effectively improve the growth performance in broiler chickens by affecting creatine metabolism and utilization efficiency of essential AA, and 600 mg/kg GAA is the minimum dose for improving performance.  相似文献   

15.
本试验旨在研究1~21日龄爱拔益加(AA)×罗曼肉杂鸡饲粮代谢能、粗蛋白质、蛋氨酸和赖氨酸的适宜水平。采用L_9(3~4)正交试验设计,饲粮代谢能水平分别为11.70、12.12、12.54 M J/kg;粗蛋白质水平分别为19.00%、20.00%、21.00%;蛋氨酸水平分别为0.45%、0.50%、0.55%;赖氨酸水平分别为1.00%、1.10%、1.20%。选取1日龄AA×罗曼肉杂鸡864只,随机分为9组,每组6个重复,每个重复16只,试验期21 d。通过饲养试验、屠宰试验等方法检测不同营养水平饲粮的饲喂效果。结果表明:1)饲粮粗蛋白质、蛋氨酸和赖氨酸水平对试验鸡平均日增重有显著影响(P0.05),21.00%粗蛋白质水平组显著高于20.00%粗蛋白质水平组(P0.05),0.50%蛋氨酸水平组显著高于0.55%蛋氨酸水平组(P0.05),1.20%赖氨酸水平组显著高于1.10%赖氨酸水平组(P0.05)。2)饲粮代谢能水平对21日龄试验鸡活体总能含量有显著影响(P0.05),12.12 MJ/kg代谢能水平组显著高于12.54 MJ/kg代谢能水平组(P0.05);饲粮蛋氨酸水平对试验鸡活体粗脂肪含量有显著影响(P0.05),0.50%和0.55%蛋氨酸水平组显著高于0.45%蛋氨酸水平组(P0.05)。3)饲粮代谢能和粗蛋白质水平对21日龄试验鸡活体能量沉积率有显著影响(P0.05),11.70和12.12 MJ/kg代谢能水平组显著高于12.54 MJ/kg代谢能水平组(P0.05),21.00%粗蛋白质水平组显著高于20.00%和19.00%粗蛋白质水平组(P0.05);1.10%赖氨酸水平组的试验鸡活体赖氨酸沉积率显著高于1.20%赖氨酸水平组(P0.05)。4)饲粮赖氨酸水平对试验鸡血清葡萄糖、尿酸、尿素氮水平有显著影响(P0.05),1.00%赖氨酸水平组血清葡萄糖水平最高,显著高于1.20%赖氨酸水平组(P0.05),1.10%赖氨酸水平组血清尿酸水平最高,显著高于1.20%赖氨酸水平组(P0.05),1.20%赖氨酸水平组血清尿素氮水平最高,显著高于1.10%赖氨酸水平组(P0.05)。5)由回归分析得出1~21日龄AA×罗曼肉杂鸡饲粮代谢能、粗蛋白质、蛋氨酸和赖氨酸适宜水平的计算公式分别为ME=45.33W~(0.75)+183.84△W,CP=19.77 W~(0.75)+626.47△W,Met=1.44 W~(0.75)+10.31△W,Lys=3.01 W~(0.75)+21.28△W(M E为代谢能,W~(0.75)为代谢体重,△W为平均日增重,CP为粗蛋白质,Met为蛋氨酸,Lys为赖氨酸),根据公式计算得出饲粮代谢能、粗蛋白质、蛋氨酸和赖氨酸的适宜水平分别为11.90 MJ/kg、21.08%、0.51%和1.05%。  相似文献   

16.
The effect of feeding varying dietary lysine to energy levels on growth and haematological values of indigenous Venda chickens aged 8 – 13 weeks was evaluated. Four hundred and twenty Venda chickens (BW 362 ± 10 g) were allocated to four dietary treatments in a completely randomized design. Each treatment was replicated seven times, and each replicate had fifteen chickens. Four maize–soya beans‐based diets were formulated. Each diet had similar CP (150 g/kg DM) and lysine (8 g lysine/kg DM) but varying energy levels (11, 12, 13 and 14 MJ ME/kg DM). The birds were reared in a deep litter house; feed and water were provided ad libitum. Data on growth and haematological values were collected and analysed using one‐way analysis of variance. Duncan's test for multiple comparisons was used to test the significant difference between treatment means (p < 0.05). A quadratic equation was used to determine dietary lysine to energy ratios for optimum parameters which were significant difference. Results showed that dietary energy level influenced (p < 0.05) feed intake, feed conversion ratio, live weight, haemoglobin and pack cell volume values of chickens. Dry matter digestibility, metabolizable energy and nitrogen retention not influenced by dietary lysine to energy ratio. Also, white blood cell, red blood cell, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration in female Venda chickens aged 91 days were not influenced by dietary lysine to energy ratio. It is concluded that dietary lysine to energy ratios of 0.672, 0.646, 0.639 and 0.649 optimized feed intake, growth rate, FCR and live weight in indigenous female Venda chickens fed diets containing 8 g of lysine/kg DM, 150 g of CP/kg DM and 11 MJ of ME/kg DM. This has implications in diet formulation for indigenous female Venda chickens.  相似文献   

17.
This experiment was designed to investigate the effects of a dietary organic acid (OA) mixture and 2 fiber sources on performance, intestinal morphology, immune responses and gut microflora in broilers. A total of 390 one-day-old broiler chicks (Ross 308) were allocated to 6 dietary treatments with 5 replicate pens and 13 chicks each based on a factorial arrangement (2 × 3) in a completely randomized design. The experiment lasted 42 d. The following experimental diets and as well as their interaction were considered: a basal diet supplemented with or without OA (0 or 1 g/kg) and 2 fiber sources (sugar beet pulp [soluble fiber] or rice hull [insoluble fiber]; 0 or 30 g/kg). Dietary supplementation of OA increased daily weight gains of broilers across the entire rearing period (P < 0.05). The dietary fibrous materials did not affect the performance of broilers. Antibody titer against influenza disease virus was higher in birds fed diets containing rice hull compared with other experimental groups (P < 0.05). The population of Lactobacillus bacteria was greater in birds fed OA-added diets without or with 30 g/kg rice hull supplementation compared with other experimental groups (P < 0.05). In conclusion, dietary supplemental OA improved performance of broilers, and dietary supplemental OA with rice hull enhanced humoral immune responses.  相似文献   

18.
本试验旨在通过研究饲粮代谢能(metabolizable energy,ME)和粗蛋白质(crude protein,CP)水平对内仔鸡生长性能和屠宰指标的影响,建立生长性能与ME、CP的回归关系模型,并运用所建模型选择具有最佳效益的ME、CP水平.采用ME和CP 3×3随机交叉试验设计,将饲粮分为9个处理,3个ME水平分别为13.18、12.55、11.92MJ/kg,3个CP水平分别为21.50％、20.50％、19.50％.选取1日龄爱拔益加(AA)肉仔鸡1 080只,随机分为9组,每组3个重复,每个重复40只鸡,1 ～21日龄分别饲喂对应试验饲粮,22～42日龄饲喂相同的饲粮.结果表明:1)试验饲粮ME、CP水平对1～21日龄体重和耗料量有显著影响(P＜0.05),对42日龄体重也有显著影响(P＜0.05).2)随着饲粮ME水平的提高,21和42日龄肌胃指数显著降低(P＜0.05),42日龄腹脂率显著增加(P＜0.05).3)应用二元曲线逐步回归方法建立了体重、耗料量与饲粮ME、CP水平的回归关系模型.应用举例表明,建立的回归关系模型对确定肉仔鸡饲粮最佳效益的ME、CP水平有很强的实用性.  相似文献   

19.
Today, several strategies are being used to decrease the serious effects of antibiotics abuse on broilers industry and public health, among which synbiotics are one of the most promising antibiotic alternative. This study was undertaken to assess the effects of synbiotics, which composed of probiotics (Bacillus subtilis) and prebiotics (xylooligosaccharide and mannanoligosaccharide), on growth performance, intestinal morphology, sIgA content and antioxidant parameters of broilers. Four hundred and fifty one‐day‐old commercial Cobb48 broilers were assigned to five treatments consisting of six replicates of 15 birds each pen. Five dietary treatments include basal diets (control), basal diets plus antibiotics (4 mg/kg Xanthomycin), basal diets plus 1 g of probiotics B. subtilis product/kg of diets (4 × 108 cfu/kg), basal diets plus 150 mg/kg xylooligosaccharide (35%) and 1 g/kg mannanoligosaccharide (75%), and basal diets plus synbiotics (1 g of probiotics B. subtilis product/kg of diets (4 × 108 cfu/kg), 150 mg/kg xylooligosaccharide (35%) and 1 g/kg mannanoligosaccharide (75%). The results demonstrated that on 21 and 42 days, dietary supplementation of the synbiotics significantly increased daily weight gain (p < 0.05), feed efficiency (p < 0.05), the villus height and villus:crypt ratio in the duodenum, jejunum and ileum (p < 0.05), as well as intestinal mucosa sIgA content (p < 0.05), serum T‐SOD activity (p < 0.05) and lysozyme content (p < 0.05), comparing with control group. In conclusion, synbiotics (B. subtilis and xylooligosaccharide and mannanoligosaccharide) is one of the safe and ideal dietary supplementations to increase broilers' growth performance by improving small intestinal morphology, sIgA content and antioxidant capabilities.  相似文献   

20.
Pea starch consists predominantly of C-type of amylopectin chain which is more resistant to digestive enzymes than A-type of starch thus slowly digested in poultry. It was hypothesized that the presence of slowly digested pea starch in broiler diets will increase net energy and the efficiency of energy utilization in broilers. Two experiments were performed to investigate starch digestibility of pea at different incubation times (in vitro study) and the effect of dietary pea on heat increment and net energy in broilers using an open-circuit respiratory calorimetry system (in vivo study). One-day-old Ross 308 male broilers were fed a common starter crumble from d 1 to 10 and standard grower diets thereafter. At d 21, birds were transferred to the chambers each housing 2 birds. Each treatment was replicated 6 times with 2 identical runs of 3 replicates per treatment. A wheat-soybean meal-based diet was used as a control and the treatment diet contained 500 g of pea/kg pea. In vitro study showed that pellet processing increased (P < 0.001) starch digestibility, particularly at shorter times for wheat and a much larger response for pea. Birds offered the pea-based diet had lower (P = 0.002) feed intake, lower (P = 0.020) body weight gain, but a similar (P > 0.05) FCR compared to those offered the wheat-based diet. Net energy (NE) and apparent metabolizable energy (AME) values were higher in the pea-based diet than in the wheat-based diet (P = 0.037 for NE and P = 0.018 for AME). Heat production, respiratory quotient, heat increment of feed, efficiency of utilization of gross energy for AME, and efficiency of utilization of AME for NE did not differ (P > 0.05) between the 2 treatments. There was no effect (P > 0.05) of pea on the total tract digestibilities of dry matter, crude protein and ash, but the total tract digestibility of starch was higher (P = 0.022) in the pea-based diet compared to the wheat-based diet. This study provides insight into the energy metabolism of broilers offered a pea-based diet and indicates that dietary pea supplementation increases dietary AME and NE but has no effect on heat increment of feed and the efficiency of energy utilization in broilers.  相似文献   

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