Effects of methionine and guanidinoacetic acid supplementation on performance and energy metabolites in breast muscle of male broiler chickens fed corn-soybean diets

ABSTRACT

1. Guanidinoacetic acid (GAA) is the single endogenous precursor of creatine, which plays a critical role in energy homeostasis of cells. Since GAA is endogenously converted to creatine by methylation, it was hypothesised that the effects of dietary GAA supplementation might determine the methionine (Met) availability in corn-soybean based diets.

2. A total of 540, one-day-old male Ross 308 broilers were allocated to nine dietary treatments with six replicates (10 birds each) in a 3 × 3 factorial arrangement with three graded levels of supplementary Met (+0.4 g/kg per level), whilst cystine was equal across groups, resulting in a low, medium and high level of total sulphur amino acids, and with three levels of GAA (0, 0.6 and 1.2 g/kg). Birds were fed for 42 days.

3. Increasing levels of supplemental Met enhanced performance indices in all rearing periods, although there was no effect on feed conversion ratio in the grower or feed intake in the finisher periods. Final body weight was 8.8% and 14.6% higher in the birds fed medium and high Met diets, respectively, compared to the low Met level. Relative breast weight and protein content in muscle on d 25 linearly increased with higher levels of Met. At low and high Met levels, growth in the finisher phase was negatively affected by supplementing GAA at 1.2 g/kg. It was suggested that disturbances in methylation homeostasis and/or changes in Arg metabolism might explain these findings. At the end of the grower phase, muscle creatine content was higher when feeding GAA at 0.6 and 1.2 g/kg (4464 and 4472, respectively, vs. 4054 mg/kg fresh muscle in the control group).

4. The effects of dietary GAA supplementation were influenced by the dietary Met level only in the finisher period, which indicates the need for proper sulphur amino acid formulation in diets when feeding GAA.     

鸡胚给养氨基酸对肉仔鸡孵化率和胚胎生长的影响

本试验将90枚孵化第18天的落盘肉仔鸡胚蛋随机分为3组,分别向羊膜腔注射0.5mL复合氨基酸溶液、0.5mL生理盐水和不注射(对照组),研究对孵化率和后期胚胎生长的影响。结果显示:各处理组间的孵化率和出壳体重无显著差异(P>0.05),但出壳重与第18天胚蛋重的比值有显著差异(P<0.05),注射氨基酸组比对照组增加2.3%。这些结果表明鸡胚给养氨基酸可有效增加肉鸡出壳重。     

理想氨基酸水平对肉仔鸡生产性能和屠体性状的影响

试验选用1日龄爱拔益加商品代肉仔鸡600只(公母各半),随机分为3个组,每组8个重复,每个重复25只鸡。分别饲喂高、中、低理想氨基酸水平的日粮,研究理想氨基酸水平对肉仔鸡生产性能和屠体性状的影响。结果表明,0~44日龄中氨基酸水平组和高氨酸水平组的出栏重显著高于低氨酸水平组(P<0.05)。高氨基酸水平组腹脂率显著低于低氨基酸水平组41.63%(P<0.05);高氨基酸水平组大腿肉率和净腿肉率均显著高于中和低氨基酸水平组(P<0.05)。     

Effects of guanidinoacetic acid supplementation on nitrogen retention and methionine flux in cattle

Creatine stores high-energy phosphate bonds in muscle and is synthesized in the liver through methylation of guanidinoacetic acid (GAA). Supplementation of GAA may therefore increase methyl group requirements, and this may affect methyl group utilization. Our experiment evaluated the metabolic responses of growing cattle to postruminal supplementation of GAA, in a model where methionine (Met) was deficient, with and without Met supplementation. Seven ruminally cannulated Holstein steers (161 kg initial body weight [BW]) were limit-fed a soybean hull-based diet (2.7 kg/d dry matter) and received continuous abomasal infusions of an essential amino acid (AA) mixture devoid of Met to ensure that no AA besides Met limited animal performance. To provide energy without increasing the microbial protein supply, all steers received ruminal infusions of 200 g/d acetic acid, 200 g/d propionic acid, and 50 g/d butyric acid, as well as abomasal infusions of 300 g/d glucose. Treatments, provided abomasally, were arranged as a 2 × 3 factorial in a split-plot design, and included 0 or 6 g/d of l-Met and 0, 7.5, and 15 g/d of GAA. The experiment included six 10-d periods. Whole body Met flux was measured using continuous jugular infusion of 1-¹³C-l-Met and methyl-²H₃-l-Met. Nitrogen retention was elevated by Met supplementation (P < 0.01). Supplementation with GAA tended to increase N retention when it was supplemented along with Met, but not when it was supplemented without Met. Supplementing GAA linearly increased plasma concentrations of GAA and creatine (P < 0.001), but treatments did not affect urinary excretion of GAA, creatine, or creatinine. Supplementation with Met decreased plasma homocysteine (P < 0.01). Supplementation of GAA tended (P = 0.10) to increase plasma homocysteine when no Met was supplemented, but not when 6 g/d Met was provided. Protein synthesis and protein degradation were both increased by GAA supplementation when no Met was supplemented, but decreased by GAA supplementation when 6 g/d Met were provided. Loss of Met through transsulfuration was increased by Met supplementation, whereas synthesis of Met from remethylation of homocysteine was decreased by Met supplementation. No differences in transmethylation, transsulfuration, or remethylation reactions were observed in response to GAA supplementation. The administration of GAA, when methyl groups are not limiting, has the potential to improve lean tissue deposition and cattle growth.     

日粮共轭亚油酸对黄羽肉鸡生长性能及血清中瘦素和脂联素的影响

选用60只1日龄黄羽肉鸡,研究共轭亚油酸(CLA)对其生长性能、腹脂沉积的影响。结果显示,日粮中添加CLA可显著提高49日龄黄羽肉鸡腿肌重(P<0.05),显著降低母鸡的腹脂沉积(P<0.05),但对母鸡的体增重有抑制作用(P<0.05),且能提高血清中瘦素水平(P<0.05)。     

苯甲酸和精油对肉鸡生长性能、抗氧化状态和肠道微生物群的影响

本研究开展了3个饲养试验,旨在探讨苯甲酸和精油单独或联合使用对肉鸡生长性能、肠道微生物含量及肝脏抗氧化性能的影响.试验1和2均选择1日龄肉鸡450只,分为3组,每组5个重复,每个重复30只.对照组均饲喂相同的基础日粮,试验1处理组肉鸡分别饲喂基础日粮添加1.5和3?g/kg苯甲酸,试验2处理组肉鸡分别饲喂日粮添加2和4...     

稻草菌糠对AA肉鸡生长性能及内分泌代谢的影响

选取192羽1日龄健康AA肉鸡(公母各半),随机分为4组,对照组饲喂基础日粮,试验1组、试验2组和试验3组,分别饲喂在基础日粮中添加0.5%、1.0%和2.0%的稻草菌糠的日粮,研究不同添加水平稻草菌糠对AA肉鸡生长性能和内分泌代谢的影响,并确定最适添加比例。结果表明:(1)与对照组相比,49日龄时,试验1组体增重提高6.24%(P0.05),采食量提高6.74%(P0.01);(2)试验组血清T3、T4和胰岛素水平显著高于对照组。在基础日粮中添加0.5%的稻草菌糠能有效地提高AA肉鸡的生长性能和调节其内分泌代谢。     

日粮中肽和氨基酸比例对肉鸡生长性能和生理生化指标的影响

1日龄商品代艾维茵公肉仔鸡350只,随机分为7个处理组,每处理组5个重复,分别采食7组日粮,试验期21d。第1组是玉米–豆粕–酪蛋白型基础日粮,酪蛋白中氮占基础日粮总氮的30%。第2、3、4组日粮为肽组,分别用肽替代基础日粮中酪蛋白的1/3、2/3、3/3,第5、6、7组为氨基酸组,氨基酸同样替代基础日粮中1/3、2/3、3/3的酪蛋白。结果表明:日粮中肽和氨基酸水平影响肉鸡生长,当日粮中肽和氨基酸比例在一定水平增加时,促进肉鸡增重,同时提高采食量,引起料肉比增加,血清中胆固醇、甘油三脂和高、低密度脂蛋白含量有先升高后降低的趋势,并且氨基酸对这一趋势的影响大于肽的影响。血清中总蛋白、白蛋白含量随日粮中肽和氨基酸水平增加而提高,血清尿酸含量提高,并且血清生长激素和T3含量随日粮肽和氨基酸水平增大也有提高趋势。     

小麦型日粮添加木聚糖酶和植酸酶对肉鸡生长性能、回肠氨基酸表观消化率及常量元素沉积的影响

本文旨在研究小麦型日粮中添加木聚糖酶和植酸酶对肉鸡生长性能、回肠氨基酸表观消化率及矿物元素沉积的影响。试验选择1日龄科宝白羽肉仔鸡850只,随机分成5组,每组5个重复,每个重复34只鸡。一共有5种日粮,即低磷日粮、高磷日粮、低磷日粮+2000 IU/kg木聚糖酶、低磷日粮+500 FTU/kg植酸酶,低磷日粮+2000 IU/kg木聚糖酶+500 FTU/kg植酸酶,试验进行21 d。低磷组较高磷组显著降低了肉鸡的日增重、日采食量及趾骨灰分含量(P <0.05),与低磷组相比,木聚糖酶组显著降低了肉鸡的料比(P <0.05),而植酸酶组显著提高了肉鸡日增重、日采食量、趾骨灰分及饲料利用率(P <0.05)。复合酶组显著提高了15种氨基酸回肠表观消化率(P <0.05)。与低磷组相比,木聚糖酶组显著提高了表观消化能和可消化代谢能及回肠氮消化率(P <0.05),而植酸酶显著提高了氮沉积及回肠氮消化率(P <0.05),复合酶组显著提高了代谢能、可消化代谢能及氮沉积量(P <0.05)。植酸酶和复合酶组较高磷组显著提高了磷表观消化率和沉积量(P <0.05),但低磷组较高磷组显著提高了钙的表观消化率(P <0.05),植酸酶酶和复合酶组较其他3组显著提高了钾的沉积量(P <0.05)。结论 :小麦型日粮同时添加植酸酶和木聚糖酶对肉鸡生长和消化的影响要优于单独添加这两种酶。     

植酸酶、柠檬酸和碳酸化合物酶对肉鸡生长性能和养分利用率的影响

文章旨在研究低磷、低钙水平日粮添加植酸酶、柠檬酸和碳水化合物酶对1~21 d肉鸡生长性能及养分消化率的影响。试验选择1日龄肉仔鸡576只,随机分为6组,每组4个重复,每个重复24只鸡。试验共分为6种日粮,阳性对照组日粮(正常钙磷水平)、阴性对照日粮(低磷、低钙)、阴性对照日粮+600 IU/kg植酸酶,阴性对照日粮+600 IU/kg植酸酶+5 g/kg柠檬酸,阴性对照日粮+600 IU/kg植酸酶+500 mg/kg复合碳水化合物酶,阴性对照日粮+600 IU/kg植酸酶+5 g/kg柠檬酸+500 mg/kg复合碳水化合物酶。试验共开展21 d。结果显示:阳性对照组肉鸡日增重和采食量显著高于阴性对照组(P<0.05);植酸酶组添加碳水化合物酶较单独添加植酸酶组显著提高了肉鸡的日增重(P<0.05);植酸酶+碳水化合物酶较阴性对照组显著改善了料肉比(P<0.05)。阳性对照组较阴性对照组显著提高肉鸡胫骨灰分含量(P<0.05);植酸酶组显著提高了总磷、有效磷和植酸磷的回肠表观消化率(P<0.05),同时植酸酶组添加柠檬酸或碳水化合物酶进一步提高了总磷和植酸磷的回肠表观消化率(P<0.05)。阴性对照组添加植酸酶显著提高了表观代谢能及干物质、总能、氮和总磷的表观沉积量(P<0.05),而植酸酶组添加碳水化合物酶提高了干物质和总磷表观沉积量(P<0.05)。结论:在本试验条件下,低磷、低钙水平日粮添加植酸酶和碳水化合物酶改善了肉鸡生长性能、提高了营养物质的消化率和沉积量,而植酸酶日粮添加柠檬酸可以改善营养物质消化率和沉积量。     

不同氨基酸限量水平对肉鸭的生长性能和胴体特征的影响

本研究旨在评估日粮不同氨基酸水平对1～56?d肉鸭生长性能和胴体特征的影响.将平均初始体重为(55.92±0.56)g的800只1日龄肉鸭随机分为5组,每组4个重复,每个重复40只.各组肉鸭在1～21?d时饲喂赖氨酸、蛋氨酸+胱氨酸、苏氨酸水平分别为0.90％+0.75％+0.70％、1.0％+0.80％+0.80％、...     

添加不同油脂对肉鸡生长性能的影响

本文旨在研究饲喂不同油脂对肉鸡生长性能及油脂酸价对采食量和体重的影响。试验选用1日龄罗斯308商品肉仔鸡2100只,随机分为7个处理组,每个组10个重复。处理1组添加豆油,处理2组添加鸡鸭油,处理3组添加精炼混合油A(酸价1 mgKOH/g),处理4～6组分别添加不同酸价的劣质混合油A、B和C(酸价分别为8、35 mgKOH/g和53 mgKOH/g),处理7组添加劣质脂肪酸。结果表明,日粮添加劣质脂肪酸组可显著增加8～21、36～42日龄及1～42日龄肉鸡日采食量和料肉比(P<0.05)。劣质混合油C组8～21日龄肉鸡的采食量显著低于其他处理组;而与豆油组比,劣质混合油B和C组8～21日龄肉鸡日增重和21日龄体重显著降低。混合油的酸价与肉鸡采食量及42日龄体重呈负相关,随着酸价的升高,1～42日龄肉鸡平均采食量和42日龄体重逐渐降低,其中劣质混合油C组采食量显著降低。     

In ovo feeding of creatine pyruvate modulates growth performance,energy reserves and mRNA expression levels of gluconeogenesis and glycogenesis enzymes in liver of embryos and neonatal broilers

The effects of in ovo feeding (IOF) of creatine pyruvate (CrPyr) on the growth performance, energy reserves and mRNA expression levels of gluconeogenesis and glycogenesis enzymes in liver of late‐term embryos and neonatal broilers were investigated. After candling on 16 day of incubation, a total of 960 eggs were randomly assigned to three treatments: (i) non‐injected control, (ii) saline group injected with 0.6 ml of 0.75% physiological saline and (iii) Creatine pyruvate group injected with 0.6 ml of physiological saline containing 12 mg CrPyr/egg. After hatching, 120 male chicks with average body weight (BW) were randomly allocated into each treatment group for a 7‐day feeding trial. The results showed that broilers subjected to CrPyr treatment had higher BW than those of the control and saline groups on 1, 3 and 7 day post‐hatch, as well as the yolk sac weight on 19 day of incubation (19 E), the day of hatch and 3 day post‐hatch (p < .05). Compared with the control and saline groups, IOF of CrPyr increased the plasma creatine concentration on the day of hatch, and the plasma pyruvate concentration on the day of hatch and 3 day post‐hatch (p < .05). Moreover, IOF of CrPyr increased the liver pyruvate and glucose concentrations on 19 E and the day of hatch, and the liver glycogen concentration during the experiment (p < .05). Broilers in the CrPyr group showed increased mRNA expression levels of pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK) and glycogen synthase 2 (GYS2) on 19 E and the day of hatch (p < .05). These results indicated that IOF of CrPyr increased energy reserves in liver of embryos and neonatal broilers possibly through upregulating the mRNA expression levels of PC, PEPCK and GYS2, which could benefit the increase of BW in broilers on 7 day post‐hatch.     

植物粉剂对肉鸡生长性能、肠道菌群数量和肌肉脂肪酸的影响

文章旨在评估植物粉剂(大蒜粉和石莲花粉)对1～42?d肉鸡生长性能、肠道菌群和肌肉脂肪酸组成的影响.试验选择平均初始体重为(48.33±0.47)g的1日龄商品肉仔鸡640只,随机分为4组,每组5个重复,每个重复32只.对照组饲喂基础日粮,药物组肉鸡饲喂基础日粮,但通过饮水补充2?mg/L维吉尼亚霉素水溶剂,大蒜粉组肉...     

Effects of dietary water‐soaked barley on amino acid digestibility,growth performance,pork quality and Longissimus dorsi muscle fatty acid profiles in pigs

Two experiments were conducted to assess the feeding value of water‐soaked barley (WB) as a replacement for dehulled barley (DB) in pigs. In experiment (Exp.) 1, eight barrows (body weight = 30.56 ± 0.78 kg) were fitted with a T‐cannula and allotted to a duplicated 4 × 4 Latin square design: WB10, 100g/kg WB; WB20, 200 g/kg WB; DB10, 100 g/kg DB; and DB20, 200 g/kg DB. In Exp. 2, 80 barrows (body weight = 70.56 ± 1.29 kg) were used in a 56‐day experiment: (i) WB15, 150 g/kg WB; (ii) WBD10, 100 g/kg WB and 50 g/kg DB; (iii) WBD5, 50 g/kg WB and 100 g/kg DB; and (iv) DB15, 150 g/kg DB. In Exp. 1, the apparent ileal digestibilities of total essential amino acids were higher (P < 0.05) in WB10 treatment than DB20. For Exp.2, the WB15 and WBD10 had higher pH and lower cooking loss (P < 0.05) than other two treatments. The WB15 treatment decreased (P < 0.05) the contents of palmitic acid (C16:0) in Longissimus dorsi muscle than WBD5 and DB15 treatments. In conclusion, it is suggested that water‐soaked barley improved some amino acid digestibility and the cooking loss and moderate fatty acid profiles in Longissimus dorsi muscle.     

高剂量植酸酶对肉鸡生长性能和消化率的影响

文章旨在研究植酸酶对1~42日龄肉鸡生长发育的影响。采用完全随机试验设计,试验共分为5组,每组6个重复,每个重复24只鸡,各组分别为阳性对照组、负对照、负对照日粮+1000、2000和3000IU/kg植酸酶,试验结束后测定各组对骨功能、骨质量和血液矿物质的影响。随着日粮植酸酶添加水平的升高,显著改善了1~21d肉鸡日增重、采食量和料比(P<0.05),而1~42d肉鸡生长性能表现为显著二次曲线效应(P<0.05),其中负对照组肉鸡日增重和采食量最低(P<0.05),料比最高(P<0.05)。对照组较负对照组显著提高了42d肉鸡胫骨干物质含量(P<0.05)。随着植酸酶添加水平的升高,21d肉鸡血钙浓度表现为显著线性降低(P<0.05),而血磷浓度先升高后降低,负对照日粮+1000IU/kg植酸酶组最高(P<0.05)。42d肉鸡血磷浓度随日粮植酸酶水平的升高表现为二次曲线效应。对照组和负对照组较处理组显著提高了42d肉鸡血钙浓度(P<0.05)。与对照和负对照组相比,负对照添加植酸酶组显著降低了矿物质回肠表观消化系数(P<0.05),而负对照组+3000IU/kg植酸酶较对照组显著降低了能量回肠表观消化系数(P<0.05)。植酸酶在回归分析的基础上提高了肉鸡生长性能,添加高剂量植酸酶3000IU/kg显著提高21d肉鸡日增重。试验为期42d,日粮添加2000IU/kg植酸酶对肉鸡的增重和饲料转化率效果较好。     

甘露寡糖对肉鸡生长性能及肠黏膜形态的影响

选择120只1日龄肉鸡随机分为2组,试验组添加0.3%的甘露寡糖。每组6个重复,每个重复10只。每组基础日粮相同。试验结果表明:试验后期(4~5周龄)和整个试验期(0~5周龄)的增重,添加0.3%甘露寡糖组显著高于对照组(P<0.05),试验前期(0~3周龄)未见明显效果。试验前期的料肉比,添加0.3%甘露寡糖组显著低于对照组(P<0.05),试验后期和整个试验期处理组虽然均低于对照组,但无显著差异。添加0.3%甘露寡糖组回肠绒毛长度以及绒毛长度与隐窝深度之间的比值均显著高于对照组(P<0.05)。添加0.3%甘露寡糖可显著提高肉鸡的生长性能,并可以改善肠黏膜的形态,增大小肠吸收面积。     

Effect of L‐theanine on meat quality,muscle amino acid profiles,and antioxidant status of broilers

This study investigated the effect of L ‐theanine on carcass traits, meat quality, muscle antioxidant capacity, and amino acid (AA) profiles of broilers. Three hundred 1‐day‐old Ross 308 male broilers were randomly allotted to five groups with six replicates. Birds were fed the basal diet or basal diet with 300, 600, 900, or 1,500 mg/kg L ‐theanine for 42 consecutive days. The results showed that L ‐theanine quadratically increased dressing percentage, eviscerated percentage, and leg muscle yield (p < .05). Meanwhile, drip loss, cooking loss, shear force, L*_24h, and muscle lactate content decreased quadratically in response to dietary L ‐theanine supplementation (p < .05), while pH_24h and muscle glycogen content were quadratically improved by L ‐theanine (p < .05). Notably, the contents of muscle malondialdehyde and protein carbonyl, and the activities of muscle total antioxidant capacity, catalase, and glutathione peroxidase decreased quadratically in response to dietary L ‐theanine supplementation (p < .05), suggesting that the oxidative stress level of muscle was decreased quadratically. Moreover, L ‐theanine quadratically increased the concentrations of most of muscle essential AA, nonessential AA, and flavor AA (p < .05). In conclusion, L ‐theanine can be used as a valuable feed additive to modulate carcass traits, meat quality, muscle antioxidant status, and AA profiles of boilers, and its optimum addition level is 600 mg/kg based on the present study.