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1.
Feeding broilers barley-based diets requires special consideration primarily due to effects on increased digesta viscosity and decreased nutrient digestion. Pelleting and glucanase supplementation are commonly performed prior to feeding broilers barley-based diets; however, the interaction of these practices is complex. The objective of this study was to establish a comprehensive evaluation of glucanase efficacy including: degree of processing, activity postpelleting, broiler performance, and digesta viscosity. Treatments were arranged in a 5 (diet formulation) × 2 (processing) factorial in a randomized complete block design with 8 replications/treatment. The 5 diet formulations consisted of positive control (PC), negative control (NC), glucanase A (GA) 125 or 1,000 β-Glu-U/kg feed, and glucanase B (GB) 1,000 β-Glu-U/kg feed. The PC and NC diets differed in metabolizable energy by 150 kcal/kg and enzymes were added to NC formulations. Diets were either fed as unprocessed mash or ground pellets. Diet formulation × processing did not interact for feed intake (FI), FCR, or total tract viscosity (P > 0.05); however, a trend was observed for ending bird weight, demonstrating that for ground pellets, GA 1,000 β-Glu-U/kg feed was improved relative to NC and similar to PC (P = 0.0903). Benefits associated with GB were not of similar magnitude, perhaps in part due to a 50% decrease in activity postpelleting. In addition, GA benefits were not suggested for unprocessed mash. The main effect processing was significant (P < 0.0001) demonstrating that broilers fed ground pellets resulted in greater pen ending bird weight, FI, and bird live weight gain (LWG) compared to birds fed unprocessed mash diets. Evaluations of glucanase should go beyond in vitro activity and include live bird performance using feed that has undergone pelleting.  相似文献   

2.
The experimental design consisted of 5 dietary treatments including a positive control (PC), a negative control (NC; with a reduction of 88 kcal/kg of AME through the starter and grower 1 phase and a reduction of 132 kcal/kg of AME in the grower 2, finisher, and withdrawal phases compared with the PC), and the NC supplemented with either β-mannanase, nonstarch polysaccharide-degrading enzymes (NSPase; cocktail carbohydrase), or β-mannanase and NSPase intermittently fed. The intermittent treatment included β-mannanase from d 1 to 21 (starter and grower 1 phases) and NSPase from d 22 to 47. Each treatment included 9 replicate pens with 35 male broilers placed per replicate (1,575 total chicks placed). The dietary program consisted of 5 dietary phases, including the starter through d 10, grower 1 through d 21, grower 2 through d 32, finisher through d 40, and withdrawal through d 47. Broilers were weighed and feed consumption determined on days of dietary changes. On d 48, following an 8-h feed withdrawal, 6 broilers from each replicate pen were removed and processed for whole bird and fat pad measurements. The reduction in energy in the NC diet reduced BW and increased mortality rate, and the inclusion of β-mannanase and NSPase separately and intermittently in the NC diet improved growth performance and reduced mortality to levels that were comparable to the PC. The NC yielded the highest cumulative mortality-corrected FCR and all enzyme inclusion treatments reduced FCR to levels comparable to the PC for the duration of the trial. The NC diet yielded the lowest processing yields and the inclusion of β-mannanase and NSPase separately and intermittently increased multiple processing parameters to a level similar to the PC. These data confirm the ability of β-mannanase and NSPase inclusion separately and intermittently to improve performance parameters in reduced-energy broiler diets.  相似文献   

3.
本试验旨在研究在低粗蛋白质(CP)饲粮中添加甘氨酸(Gly)对肉仔鸡生长性能、胴体组成和血液生化指标的影响。选用180只1日龄健康爱拔益加(AA)肉仔鸡(公雏),随机分为3组,每组6个重复,每个重复10只。3组分别为:正对照(PC)组,前期和后期饲粮CP水平分别为22.0%和20.0%;负对照组,前期和后期饲粮CP水平分别为18.0%和15.5%;Gly组,在负对照组基础上添加Gly,使饲粮Gly和丝氨酸水平为2.32%。试验期42 d,分为前期(1~21 d)和后期(22~42 d)2个阶段。结果表明:1)饲粮CP水平降低4.0~4.5个百分点,试验1~21 d的料重比(F/G)显著升高(P0.05),22~42 d的平均日增重(ADG)显著降低(P0.05);添加Gly后,1~21 d F/G显著降低(P0.05),22~42 d ADG显著升高(P0.05),达到了与PC组相似的生长性能。2)CP水平降低,肉仔鸡42日龄胸肌率降低了9.5%(P0.05)、腹脂率提高了60.3%(P0.05);添加Gly后,胸肌率提高了17.6%(P0.05),腹脂率降低了34.6%(P0.05),获得了与PC组相似的胴体组成。CP水平降低、添加Gly均未显著影响屠宰率、全净膛率和腿肌率(P0.05)。3)各组间血液生化指标均无显著差异(P0.05)。可见,低CP饲粮中添加Gly可以改善生长性能和胴体组成,结果提示了Gly在肉仔鸡低CP饲粮中的可应用性。  相似文献   

4.
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   

5.
Two experiments were conducted to evaluate the impact of a thermotolerant xylanase on male broiler performance and dietary ileal digestible energy (IDE). The first experiment consisted of 3 treatment groups with 12 replications per treatment each containing 35 Cobb 500 males for a total of 1,260 broilers placed in floor pens for a 42 d grow-out. The experiment treatments included a corn/soy diet with DDGS control formulated at a low energy level, and the control supplemented with one of 2 concentrations of xylanase (20,000 XU/kg [XYL20] and 40,000 XU/kg [XYL40]). No significant differences in body weight were observed with the inclusion of xylanase when compared to the control diet throughout the experiment. At d 28, the inclusion of XYL20 improved (P < 0.05) mortality corrected feed conversion ratio (FCR) compared to the control diet. Feed conversion ratio was also improved (P < 0.01) at d 42 for birds fed XYL20 when compared to the control. At d 42, inclusion of XYL20 and XYL40 significantly (P < 0.05) increased IDE compared to the control. Experiment 2 consisted of 4 treatment groups with 10 replications per treatment each containing 44 Cobb 500 males for a total of 1,760 broilers placed in floor pens for a 41 d grow-out. The dietary treatments included a positive control (PC) based on a corn/soy diet containing DDGS and phytase, a negative control (NC) diet (PC -150 kcal/kg in AME), NC + xylanase at 10,000 XU/kg (XYL10), and NC + xylanase at 20,000 XU/kg (XYL20). A significant increase (P < 0.05) in BW was observed in broilers fed the inclusion of XYL20 in the NC diet increased (P < 0.05) on d 14. A significant increase in cumulative body weight gain was observed on d 27 and d 41 with xylanase (XYL20) inclusion compared to the NC. These data demonstrate that xylanase inclusion increased energy utilization through improvements in IDE, which improved broiler performance.  相似文献   

6.
1. Carcase composition, whole body nutrient accretion rates and total tract nutrient retention of broilers in response to supplemental phytase or carbohydrase and protease from 0 to 21 d of age were investigated. 2. A total of 480 broilers were allocated to 4 slaughter groups (SG) of 30, 150, 150 and 150 broilers. Thirty broilers, in 6 replicates of 5 birds, comprised the initial SG killed at d 0; 150 broilers were allocated to each of the d 7, 14 and 21 final SG. Broilers in the final SG were allocated to 5 treatments in a randomised complete block design; each treatment had 6 replicate cages of 5 broilers per replicate cage. 3. The diets were maize-wheat-soyabean based and the treatments were: (1) positive control which met NRC (1994) energy and nutrients requirements for broiler, (2) negative control (NC) deficient in metabolisable energy (ME) and P, (3) NC plus phytase added at 1000 FTU/kg, (4) NC plus cocktail of xylanase, amylase and protease (XAP), and (5) NC plus phytase and XAP. 4. Except for ash and Ca, the treatments had no effect on carcase composition. Phytase or XAP individually or combined had variable effects on body nutrient accretion rates at various age periods of the broilers compared with the NC diet. Phytase alone or combined with XAP consistently improved body accretion rates of DM, protein, fat, ash, Ca, and P. 5. Addition of phytase alone or combined with XAP to the NC diet improved total tract N and P retention compared with the NC diet. Cocktail of XAP alone or combined with phytase improved Ca retention. Combination of phytase and XAP improved metabolisable energy (ME) and dry matter retention. 6. Overall, the results showed that the exogenous enzymes used had greater effects on the rates of nutrient accumulation in the carcase rather than on the proportion of nutrients deposited in the carcase.  相似文献   

7.
【目的】 本试验旨在研究小檗碱对黄羽肉鸡器官指数、抗氧化能力和肠道免疫功能的影响。【方法】 选用1日龄快大型岭南黄羽肉鸡360只,随机分为3组,每组6个重复,每重复20只。对照组（NC）饲喂基础饲粮;抗生素组（PC）饲喂基础饲粮+200 mg/kg土霉素钙+250 mg/kg那西肽;小檗碱组（BBR）饲喂基础饲粮+250 mg/kg小檗碱。在试验第21、42和63天,从每个重复中随机挑选1只接近平均体重的鸡,采集心脏、肝脏、脾脏和法氏囊分别称重,记录重量,计算其器官指数;刮取空肠黏膜,测定超氧化物歧化酶（T-SOD）、总抗氧化能力（T-AOC）、谷胱甘肽过氧化物酶（GSH-Px）活性和丙二醛（MDA）含量;提取空肠黏膜总RNA,合成cDNA,测定紧密连接蛋白与炎症因子相关基因的mRNA表达量。【结果】 小檗碱对黄羽肉鸡器官指数无显著影响（P>0.05）。与对照组相比,在饲粮中添加小檗碱显著提高了63日龄黄羽肉鸡空肠黏膜的总抗氧化能力（T-AOC）,显著降低了63日龄黄羽肉鸡空肠黏膜的丙二醛（MDA）含量（P<0.05）。抗生素组21日龄黄羽肉鸡空肠黏膜的闭合蛋白（Occludin）和闭锁小带蛋白-1（ZO-1）的mRNA表达量均显著高于对照组和小檗碱组（P<0.05）。与对照组和抗生素组相比,小檗碱显著提高了63日龄黄羽肉鸡空肠黏膜的跨膜蛋白-1（Claudin-1）的mRNA表达量（P<0.05）,显著降低了21、42与63日龄黄羽肉鸡空肠黏膜的核苷酸结合寡聚化结构域蛋白1（NOD1）的mRNA表达量（P<0.05）;小檗碱组与抗生素组42日龄黄羽肉鸡空肠黏膜的白介素-1β（IL-1β）和白介素-8（IL-8）的mRNA表达量均显著低于对照组（P<0.05）;与对照组相比,小檗碱显著降低了63日龄黄羽肉鸡空肠黏膜的肿瘤坏死因子-α（TNF-α）、IL-1β、IL-8的mRNA表达量（P<0.05）。【结论】 饲粮中添加250 mg/kg小檗碱可增强63日龄黄羽肉鸡肠道抗氧化能力,改善肠道屏障,降低肠道炎性因子的表达,从而改善肠道免疫功能。  相似文献   

8.
A performance trial was conducted with broiler chicks to study the effect of phytase (PHY) supplementation in diets formulated with reduced AME, Ca, and P. The nutrient digestibility was determined during the 14- to 21-d and 28- to 35-d periods. The treatments consisted of 3 diets (NC1, NC2, NC3) differing in nutrient content and each diet with or without supplemental PHY (NC1, 0 or 500; NC2, 0 or 750; NC3, 0 or 1,000 U of PHY/kg feed) and 1 positive control diet (PC). Compared with the PC diet, negative control diets (NC) resulted in lower AME and apparent ileal amino acid digestibility for some amino acids. Phytase supplementation of the NC diets increased AME, apparent ileal amino acid digestibility, and apparent ileal crude protein digestibility. Phytase addition also increased mineral absorption in 21- and 35-d-old broilers fed NC diets. Reduced nutrient digestibility appears to be a factor in the weight gain and feed intake results. Reducing Ca and P content reduced feed intake in a stepwise fashion in the NC diets. Phytase increased feed intake and generally improved nutrient digestibility, which resulted in an increase in digestible nutrient intake. Averaged across NC diets, PHY improved body weight. Bone-breaking strength was the most consistent predictor of Ca and P reduction. All NC diets had significantly lower bone-breaking strength than the PC. Phytase supplementation of the NC diets gave bone-breaking strengths that were comparable to the PC. Diets with PHY had the highest bioeconomic index.  相似文献   

9.
1. In order to investigate the effects of xylanase, amylase, protease and phytase in the diets of broiler chickens containing graded concentrations of metabolisable energy (ME), two 42-d experiments were conducted using a total of 2208 broiler chicks (8 treatments with 12 replicate pens in each experiment). 2. Four diets including one positive and three negative control diets were used. Three maize/soybean meal-based negative control (NC) diets were formulated to be identical in available phosphorus (P), calcium (Ca) and amino acids but NC1 contained approximately 0.17 MJ/kg less ME than NC2 and approximately 0.34 MJ/kg less ME than NC3. A positive control (PC) was fed for comparison and was formulated to be adequate in all nutrients, providing approximately 0.63 MJ/kg ME, 0.13% available P, 0.12% Ca and 1 to 2% amino acids more than NC1. 3. The reduction in nutrient density between NC1 and PC was determined using ingredient quality models Avichecktrade mark Corn and Phychecktrade mark that can predict the response to exogenous enzymes in maize/soybean meal-based broiler diets. Supplementation of each diet with or without a cocktail of xylanase, amylase, protease and phytase gave a total of 8 dietary treatments in a 4 x 2 factorial arrangement. The same treatments and diet designs were used in both experiments but conducted in different locations using different batches of maize, soybean meal and minor ingredients. 4. In both experiments, digestibility was improved by the addition of exogenous enzymes, particularly those for P, Ca and certain amino acids. In addition, the supplementation of the PC with enzymes elicited a positive response indicating that over-the-top addition of xylanase, amylase, protease and phytase may offer a nutritionally and economically viable alternative to feed cost reduction. 5. It can be concluded that the digestibility of nutrients by broilers fed on maize/soybean meal-based diets can be improved by the use of a combination of xylanase, amylase, protease and phytase.  相似文献   

10.
Phytase supplementation beyond the standard doses used for phosphorus release has been reported to result in extraphosphoric effects by enhancing nutrient digestibility resulting in improved performance of broilers. A study was conducted to examine the effects of the progressive addition of an enhancedEscherichia Coli phytase (400–1,600 phytase units; FTU) on growth performance and carcass characteristics from 1 to 42 d of age in male broilers. One thousand four hundred Hubbard × Cobb 500 1-d-old chicks were randomly distributed into 56 floor pens (0.08 m2/bird). Seven dietary treatments were provided in a 3-phase feeding program consisting of (1) a positive control (adequate Ca and nonphytate P; PC); (2) 1 negative control (Ca and nonphytate P reduced by 0.14% and 0.13%; NC); (3 to 6) the NC diet with 4 increasing supplemental phytase concentrations (NC + 400 FTU, NC + 800 FTU, NC + 1,200 FTU, and NC + 1,600 FTU, respectively); and (7) a low-energy NC diet without phytase and xylanase (reduced 66 kcal of AMEn/kg). Body weight gain, feed conversion, mortality, weight and yield of whole carcass, abdominal fat, and pectoralis major and minor muscles were evaluated. Progressive supplementation of phytase decreased cumulative FCR linearly. Broilers fed diets containing 1,600 FTU had heavier total breast meat by 49 g compared with birds receiving the PC diets. Broilers consuming the NC + 400 FTU or the low-energy NC diet had similar growth performance and meat yield compared with birds provided PC diet. These data indicated that phytase supplementation beyond the need for phosphorus enhances growth performance and carcass characteristics.  相似文献   

11.
To evaluate a novel feed additive, hops β-acids, a pen trial using 1,440 one-day-old broiler chickens, in a randomized design with 6 treatments and 6 replicates of 40 birds/pen, was conducted. The experimental treatments were a negative control (NC) basal diet, a positive control (PC) basal diet supplemented with zinc 30 mg/kg of bacitracin, and 4 additional treatments consisting of the basal diet supplemented with 30, 60, 120, and 240 mg/kg of hops β-acids in a microencapsulated form. All birds were vaccinated against coccidiosis by eye drops. Productive performance, jejunum morphology, andClostridium spp. count in jejunum and cecum contents were evaluated. At 21 d of age, the birds fed the PC, 30, or 60 mg/kg of β-acids had the same weight gain of those fed the NC, whereas the highest level of β-acids decreased the gain. In addition, feed intake was decreased and FCR was improved in all treatments when compared with the NC. At 42 d, compared with the NC, the treatments containing 30 or 240 mg/kg of β-acids and the PC resulted in improved FCR. No differences were found for other performance variables. No difference was observed among the treatments on villus length, crypt depth, and villus-to-crypt ratio. Except for one sample, all others had negative results forClostridium spp. based on the methodology of sulphite reduction. In this study, we demonstrated positive effects of supplementation of hops β-acids on productive performance of broilers, and the best results were obtained with addition of 30 mg/kg.  相似文献   

12.
1. A study was conducted to investigate the effects of an esterified glucomannan (EGM), a hydrated sodium calcium aluminosilicate (HSCAS) and a compound mycotoxin adsorbent (CMA) on performance, nutrient retention and meat quality in broilers fed on mould-contaminated feed. Mould-contaminated diets were prepared by replacing half of the non-contaminated maize in the basal diets with mould-contaminated maize, which contained 450·6 μg/kg of aflatoxin B1, 68·4 μg/kg of ochratoxin A and 320·5 μg/kg of T-2 toxin. 2. The mould-contaminated diet significantly decreased body weight gain (BWG) between 10 and 21 d, feed intake (FI) between 35 and 42 d, the apparent retention of crude lipid and phosphorus, and the lightness (L*) value of breast and thigh muscle. It also significantly increased the redness (a*) and yellowness (b*) value in breast muscle and the b* value in thigh muscle. 3. The addition of 0·2% HSCAS significantly increased FI between 35 and 42 d and the apparent retention of phosphorus. Supplementation with 0·1% CMA in the contaminated diet significantly improved BWG from 10 to 21 d, and increased FI from 35 to 42 d and from 10 to 42 d. CMA also significantly increased the apparent retention of crude lipid, crude protein, ash and phosphorus. All three mycotoxin-adsorbent treatments significantly improved the L* values of breast and thigh muscle when compared with the mould-contaminated group. Supplementation with 0·1% CMA in the contaminated diet significantly decreased b* value and improved tenderness in thigh muscle. 0·05% EGM significantly decreased b* value of thigh muscle compared to mould-contaminated group. 4. The results indicated that mycotoxins in contaminated feed retard growth, nutrient retention and meat quality, whereas the addition of 0·05% EGM, 0·2% HSCAS or 0·1% CMA prevents the adverse effects of mycotoxins to varying extents, with 0·1% CMA being the most effective adsorbent treatment.  相似文献   

13.
This study evaluated the effect of a direct-fed microbial (DFM) and its combination with xylanase, amylase, and protease (XAP) enzymes cocktail on performance of broilers, in comparison with two commonly used antimicrobial growth promoters (AGPs). Five treatments were tested using day-old Ross 708 broilers (mixed sex at 50:50 ratio) in a completely randomized design with 8 replications per treatment (40 birds/pen) using built up litter. Treatments were 1) a negative control (NC) based on corn/soy/wheat (10%) containing 500FTU/kg phytase, 2) NC + DFM (150,000 CFU/g of 3 Bacillus strains) (DFM150); 3) NC+ DFM (75,000 CFU/g of 3 Bacillus strains) in combination with XAP, XAP + DFM75); 4) NC+ BMD (50 g/ton), and 5) NC+ virginiamycin (20 g/ton). Diets were fed in mash form ad libitum in 3 phases: d 1 to 10 (starter); d 11 to 21 (grower) and d 22 to 42 (finisher). Body weight and feed intake (FI) were measured per phase and feed conversion ratio (FCR) was corrected for mortality weight. Treatment means were compared using a one-way analysis of variance (ANOVA) and separated via Duncan's Multiple Range Test. Supplementation of DFM increased (P < 0.05) average BW at d 10 when compared to the NC. Overall 42-d data indicated that the combination of XAP+DFM75 reduced (P < 0.05) mortality weight corrected FCR compared to NC, both DFM150 and the combination of XAP+DFM75 did not differ from both AGP treatments. Feed intake and body weight gain (BWG) were not affected by treatments during the 42-d study. The combination of XAP+DFM75 also reduced (P < 0.05) foot-pad lesion score as well as improved energy efficiency compared to the NC. These data indicate that both DFM150 and the combination of XAP + DFM75 may be used as an alternative to AGPs to achieve similar growth performance when producing broilers chickens under similar conditions.  相似文献   

14.
The present study investigated the effect of inclusion of multi-microbe probiotic product on growth performance, apparent digestibility of nutrients, cecal microbiota and small intestinal morphology in broilers. Four hundred days-old Ross chicks were randomly allotted to five treatments on the basis of body weight (BW). Each treatment had four replicates of 20 chicks in each. Experimental diets were fed in two phases, starter (day 0-21) and finisher (day 22-35). Dietary treatments were; basal diet without any antimicrobial (NC), basal diet added with 20 mg Avilamycin/kg of diet (PC), 10(7) cfu multi-microbe probiotic/kg of diet (P1), 10(8) cfu multi-microbe probiotic/kg of diet (P2), and 10(9) cfu multi-microbe probiotic/kg of diet (P3). Overall BW gain and feed conversion ratio were better (p < 0.05) for treatments PC, P2 and P3 compared with NC and P1, with P1 being better (p < 0.05) than NC. Overall feed intake in treatments PC, P1, P2 and P3 were greater (p < 0.05) than NC. Apparent digestibility of dry matter and crude protein were greater (p < 0.05) in treatments PC, P2 and P3 compared with NC, with P1 being intermediate and not different form NC, PC, P2 and P3. At d 21 and 35, treatments PC, P1, P2 and P3 showed lower (p < 0.05) cecal Clostridium and Coliforms count in relation to NC. Moreover, cecal Clostridium (d 21) and Coliforms (d 21 and 35) count were lower (p < 0.05) in treatment PC in relation to P1; with P2 and P3 being intermediate and not different from PC. However, there was no effect of dietary treatments on cecal total anaerobic bacteria and Bifidobacterium spp. count. The villus height of duodenum in treatment PC was greater (p < 0.05) than NC, with P1, P2 and P3 being intermediate. Villus height of ileum in treatment PC was greater (p < 0.05) than in treatments P1 and NC, whereas it remained comparable among treatments PC, P2 and P3. Villus height to crypt depth ratio of ileum was greater (p < 0.05) for treatment PC, P2 and P3 compared with that in P1 and NC. It is concluded that multi-microbe probiotic inclusion at 10(8) and 10(9) cfu/kg diet had beneficial effects on broilers growth performance, apparent digestibility of nutrients and intestinal morphology and can be used as replacement to antibiotics growth promoter in broiler nutrition.  相似文献   

15.
A total of 540 2‐day‐old male Ross 308 broilers were used in a 35‐day experiment and were randomly divided into five treatments: (i) NC (low energy); (ii) PC (high energy diet); (iii) P1 (NC + 0.1% carbohydrases); (iv) P2 (NC + 0.05% emulsifier); and (v) P3 (NC + 0.1% carbohydrases + 0.05% emulsifier). From days 0 to 21, body weight gain in PC and P3 treatments increased (P < 0.05) compared with NC treatment. The chicks fed PC, P1, P2 and P3 improved (P < 0.05) feed conversion ratio compared with the NC treatment throughout the whole experiment. Abdominal fat weight was heavier (P < 0.05) in PC, P2 and P3 treatments than in NC and P1 treatments. On day 35, serum total cholesterol and low density lipoprotein cholesterol concentration were higher (P < 0.05) and high‐density lipoprotein cholesterol was lower (P < 0.05) in NC and P2 treatments than in PC, P1 and P3 treatments. The concentration of oleic acid, linoleic acid and total unsaturated fatty acids were highest (P < 0.05) in PC than in the other treatments. In conclusion, the results indicate that low energy density diet had lower growth performance, while the inclusion of emulsifier and carbohydrases in low energy diets can partially improve growth performance.  相似文献   

16.
本试验旨在研究非淀粉多糖复合酶制剂对肉鸡生产性能、养分表观利用率的影响。试验采用单因子随机分组试验设计,选取科宝肉鸡商品代1日龄公雏320只,随机分成2个处理组,各处理组8个重复,每个重复20只。处理1饲喂基础饲粮,处理2饲喂基础饲粮+150 g/t NSP复合酶制剂F。1-21 d基础饲粮采用玉米-豆粕型饲粮,22-42 d基础饲粮采用玉米-豆粕-杂粕型饲粮,低温制粒。结果表明,在1-21 d肉鸡的玉米-豆粕型饲粮中添加NSP酶制剂F对肉鸡生产性能和养分表观利用率无改善作用,而在高杂粕(3%菜粕、3%棉粕和8%DDGS)的玉米-豆粕-杂粕型肉鸡饲粮中添加NSP复合酶制剂F对22-42 d和1-42 d肉鸡生产性能均有改善作用,在一定程度上改善了22-42 d肉鸡饲粮的养分表观利用率。  相似文献   

17.

Background

Previous studies with broiler have shown dietary supplementation with multi-enzyme complex containing non-starch polysaccharides (NSP) degrading enzymes and phytase is efficient in releasing phosphorus (P), calcium (Ca), energy and amino acids from corn-soybean meal diets or corn-sorghum diets, hence compensating considerable levels of nutrients in formulation. Notwithstanding, such potentials have not been well defined in duck nutrition. Giving China being the largest duck producing country, we conducted this study to establish adequate specifications of major nutrients along with multi-enzyme complex to meat duck from day-old to slaughter, focusing on performance, utilization of nutrients and bone mineralization. Five dietary treatments were: Positive control (PC,T1 ): the nutrients concentration of diet for 1 to 14 d of age were apparent metabolizable energy(AME) 2,800 kcal/kg, crude protein (CP)19.39%, Ca 0.85%, available phosphorus (avP) 0.42%; for 15 to 35 d of age these parameters were AME 2,900 kcal/kg, CP 16.47%,Ca 0.76%,avP 0.38%; Negative control 1(NC1,T2), the AME and digestible amino acids (DAA) were reduced by 70 kcal/kg and 2.0%, avP and Ca by 1.0 g/kg from PC diet; Negative control 2( NC2,T4), the down-spec from PC diet was AME 100 kcal/kg, DAA 2.5%, avP 1.5 g/kg and Ca 1.2 g/kg; The enzyme complex was added at the same dosage (200 mL/ 1,000 kg) on NC1 (T3) and NC2 (T5) diets.

Results

Comparing with the ducks fed on T1, T3 and T5 diets, the birds fed on NC2 diet showed the lowest (P < 0.05) body weight ( d 14 and 35), feed intake (d 35), tibia ash, Ca and P contents (d 14 and 35), and the utilization of nutrients (P < 0.05). The supplementation with the enzyme complex to the NC diets restored growth rate, utilization of nutrients and bone mineralization to the level of the PC diet, and increased AME by 60 kcal/kg and 117 kcal/kg, respectively for the NC1 and NC2 diets.

Conclusion

These results suggest that down-spec AME by 100 kcal/kg, DAA by 2.5%, avP by 1.5 g/kg and Ca by 1.2 g/kg caused detrimental effects on duck performance compared with those fed on the PC diet, and these performance losses can be compensated by the addition of the multiple-enzyme complex.  相似文献   

18.
在体外试验以及预试验的基础上,通过对日粮中添加HMTBA、杆菌肽锌和益生菌,考察其对正常以及沙门氏菌CVCC518攻毒情况下肉鸡生产性能的影响。将300只雄性健康AA肉鸡随机分为5个日粮组,每组6个重复,每个重复10只鸡。试验期为42 d,分为前期(1～21 d)、后期(22～42 d),饲喂玉米-豆粕型基础日粮。结果表明:正常组中,各处理日粮都不同程度地改善了肉鸡的生产性能;HMTBA、益生菌和抗生素能够显著提高22～42 d肉鸡的日增重(P<0.05),抗生素组显著降低了22～42 d、1～42 d肉鸡的料重比(P<0.05);攻毒组中,各处理日粮都不同程度地改善了肉鸡各阶段的生产性能,但差异不显著(P>0.05)。  相似文献   

19.
This study investigated the effects of chemical treatments of salseed (Shorea robusta) meal (SSM), on intake, growth performance, feed efficiency, and activities of digestive enzymes in broilers. Five experimental iso-nitrogenous and iso-caloric diets, one without SSM (control) and four SSM based, were formulated. The four SSM diets differed in the treatment given to the SSM. The USSM diet contained untreated SSM and the three other diets were contained SSM incubated with (820 ml/ kg of SSM DM) distilled water (pH 5.3), 0.67 M acetic acid (pH 2.4), or 0.67 M sodium hydrogen carbonate (pH 8.2) for 12 h at 37 °C. Inclusion of untreated SSM in the diets markedly depressed the feed intake, growth rate and, feed efficiency in broilers. Treatment of SSM with chemicals partly alleviated these negative effects on the performance of broilers. Growth rate of broilers was significantly higher on alkali and water treated SSM diets than on USSM diet. The broilers on alkali treated SSM diet consumed more feed than those on water or acid-treated SSM diets. Alkali and water treatments of SSM significantly improved the feed efficiency in broilers fed SSM diets however; the effect due to acid treatment was negligible. Inclusion of untreated SSM in diets caused the pancreatic hypertrophy and subsequent depression in the activity of chymotrypsin and α-amylase in pancreatic tissue. Treatment of SSM with alkali and water substantially increased the activity of chymotrypsin in the pancreas. The activities of trypsin, chymotrypsin and α-amylase in the jejunum were depressed with USSM diet. This depression in broilers was partly alleviated with alkali and water treatments to SSM. The activities of dipeptidase, sucrase, and maltase in the jejunal and duodenal mucosa were also depressed with USSM diet. Activity of dipeptidase in the duodenal and jejunal mucosa of the broilers fed treated SSM was improved with alkali treatment. It can be concluded that inclusion of SSM in the diets of broilers markedly depressed the activities of pancreatic and intestinal enzymes, feed consumption, and growth rate. Treatment of SSM with water or alkali improved the digestive enzymatic activity, intake, growth, and subsequently feed efficiency in broilers.  相似文献   

20.
This study investigated the influence of Bacillus‐based probiotics on performance and intestinal health in broiler challenged with Clostridium perfringens‐induced necrotic enteritis. One‐day‐old Arbor Acre (n = 480) were randomly assigned to four treatments with 10 cages of 12 birds: (a) basal diet negative control (NC), with no probiotics nor antibiotics formulated to contain 2,930 and 3,060 kcal/kg with 24.07 and 15.98% CP, for starter and finisher diet, respectively, (b) basal diet + enramycin (5 mg/kg), an antibiotic growth promoter (AGP); (c) basal diet + Bacillus subtilis B21 at 2 × 109 CFU per g (BS); (d) basal diet + Bacillus licheniformis B26 at 2 × 109 CFU per g (BL); growth performance, intestinal morphology, intestinal lesion scores, short‐chain fatty acids (SCFAs) and mucosal barrier tight junction's (TJ) mRNA expression were assessed. NC‐ and BL‐fed groups showed higher (p = 0.005) average daily feed intake from d1 to d21 than AGP and BS, whereas BS‐ and AGP‐fed groups showed higher average daily weight gain from d22 to d42 and d1 to d42 of age. Higher mortality rate of (12.5%) and lower of (5.5%) were recorded in AGP and NC fed‐groups respectively, lesion score was higher in BS and BL than in AGP, while no lesion was observed in NC group, results revealed higher duodenum and jejunum villus height to crypt depth (VH:CD) compared with NC and BS. Probiotics‐fed groups showed higher total (SCFAs), acetic and butyric acid concentrations at d21 post‐challenge (PC) than other groups. The expression of claudin‐1 was upregulated in duodenum (d7) PC and in jejunum (d7) and (d21) PC in BL group, while at d21 PC, the expression of occludens was higher in jejunum and ileum by AGP and BL. The present study indicated both BS and BL have some similarity with AGP in preventing or partially preventing NE effect in broilers.  相似文献   

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