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1.
本试验旨在研究在湖羊全混合颗粒料中添加不同类型蛋氨酸(蛋氨酸钙盐与蛋氨酸羟基类似物异丙酯)对湖羊生长性能及血清生化指标、抗氧化指标和激素含量的影响。选取体重为(19.99±2.04) kg的健康湖羊72只,随机分为3组:对照组、试验Ⅰ组(在基础饲粮中添加1.5 kg/t蛋氨酸钙盐)和试验Ⅱ组(在基础饲粮中添加1.5 kg/t蛋氨酸羟基类似物异丙酯),每组6个重复,每个重复4只(公母各占1/2)。预试期7 d,正试期80 d。结果表明:1)与对照组相比,试验Ⅰ组、试验Ⅱ组总增重、平均日增重均有上升的趋势,其中试验Ⅰ组总增重提高了12.8%(P>0.05),试验Ⅱ组总增重提高了3.1%(P>0.05);料重比方面,试验Ⅰ组、试验Ⅱ组均有下降的趋势,其中试验Ⅰ组下降了12.2%(P>0.05),试验Ⅱ组下降了3.6%(P>0.05)。2)试验Ⅱ组血清甘油三酯(TG)、总胆固醇(TCH)、低密度脂蛋白胆固醇(LDL-C)、总蛋白(TP)含量显著高于对照组和试验Ⅰ组(P <0.05)。3)血清抗氧化指标及激素含量各组之间无显著差异(P>0.05)。综上所述,全混合颗粒料中添加蛋氨酸羟基类似物异丙酯及蛋氨酸钙盐具有提高肉羊生长速度、降低料重比的趋势,同时影响部分血清生化指标,但对血清抗氧化指标及激素含量无显著影响。  相似文献   
2.
The effect of variable taurine inclusion (Tau) (1 g/kg DM to 15 g/kg DM) in the diet of juvenile barramundi (Lates calcarifer) on growth and nutrient utilization was investigated at three levels of dietary methionine (Met) supplementation. Diets were fed to juvenile barramundi (starting weight: 26.8 g) twice daily under a restricted pair‐fed regime for a period of 42 days. No significant effect of dietary Tau supply on growth or nutrient utilization was observed at any level of Met inclusion. Numerical variations suggested a positive effect of Tau provision at the mid‐level of supplementation (6–8 g/kg DM). The best‐fit response model (5‐SKM), fitted to the percentage body weight gain data of fish fed diets with an adequate level of Met, suggested a relatively weak pattern of response (R2 = 0.183) and predicted a Tau requirement of 5.47 g/kg DM (9.64 g/kg CP) similar to that reported for several other species. It was concluded that taurine appears to be conditionally essential to barramundi, whereby provision in the diet when sulphur amino acid supply is insufficient to meet biosynthetic demands may be beneficial, but that the predicted requirement is likely reasonably accurate for use as a minimum level of inclusion.  相似文献   
3.
本试验旨在探究饲粮精料水平和蛋氨酸铬(Cr-Met)添加剂量对舍饲滩羊生长性能、屠宰性能、肉品质和脂肪沉积的影响。采用2×3双因素试验设计,2个因素分别为饲粮精料水平和Cr-Met添加剂量,其中饲粮精料水平分别设为35%(低精料饲粮,饲粮精粗比为35∶65)和55%(高精料饲粮,饲粮精粗比为55∶45),Cr-Met添加剂量分别设为0、0.75和1.50 g/(d·只)。将60只雄性滩羊羔羊[平均体重为(21±1)kg]随机分配到6个试验组,每组10只。试验期为80 d,其中预试期15 d,正试期65 d。结果显示:1)与低精料饲粮组相比,高精料饲粮组滩羊的平均日增重、屠宰率、背膘厚度、肌内脂肪含量和后腿肉比重显著增加(P<0.05),但料重比与肌肉蒸煮损失、剪切力、pH、亮度(L*)值、红度(a*)值和黄度(b*)值则显著降低(P<0.05)。2)低精料饲粮组滩羊背膘厚度、皮下脂肪厚度、肌内脂肪含量和后腿肉比重随Cr-Met添加剂量的增加而线性降低(P<0.05),但肌肉pH则线性升高(P<0.05)。3)高精料饲粮组滩羊肋肉比重、腰肉比重以及肌肉剪切力和pH随Cr-Met添加剂量的增加而线性升高(P<0.05),而肌内脂肪含量和肌肉a*值则线性降低(P<0.05)。综合本试验测定指标,建议在滩羊养殖中选择精粗比为55∶45的高精料饲粮,Cr-Met的适宜添加剂量为1.50 g/(d·只),且不建议在精粗比为35∶65的低精料饲粮中添加Cr-Met。  相似文献   
4.
A 4‐week feeding trial was conducted using five groups of hybrid grouper (61.15 ± 0.15 g) to explore the potential effects of three methionine (Met) sources. Five isonitrogenous and isolipidic diets were formulated that included a fishmeal (FM) diet; nonsupplemented (NS) diet; or NS diets with the addition of the L‐methionine (L‐Met), DL‐methionine (DL‐Met), or coated Met (Co‐Met) to obtain the same Met level as the FM diet. Fish were randomly distributed into sea cages (30 fish per cage). Weight gain and specific growth rate in the DL‐Met group and FM group were significantly higher than those in all other groups (p < .05). In the proximal and distal intestines, of the 20 gene and time combinations (10 per gene), there were 14 combinations (70%) in which there were no significant differences in gene expression levels between the FM and DL‐Met groups (p > .05). The main reason for the same growth effect between the DL‐Met and FM groups may be attributed to the synchronized absorption at most time points after feeding, which had similar expression patterns of B0AT1 and ASCT2 of the proximal and distal intestines between two groups.  相似文献   
5.
本试验旨在研究饲粮添加包被蛋氨酸(coated methionine,CM)和包被叶酸(coated folic acid,CFA)对杜寒杂交二代公羔生长性能、养分消化代谢及瘤胃微生物蛋白质合成的影响。采用2×2完全随机试验设计,试验因素为按照试验动物体重添加CFA(0 mg,CFA-或4 mg·(kg·d)-1,CFA+)和CM(0 g,CM-或0.1 g·(kg·d)-1,CM+)。将40只体重相近((30.08±1.34)kg)的4月龄杜寒杂交二代公羔随机分为4组,分别饲喂基础日粮(CM-&CFA-)、基础日粮+CFA 4 mg·(kg·d)-1(CM-&CFA+)、基础日粮+CM 0.1 g·(kg·d)-1(CM+&CFA-)、基础日粮+CFA 4 mg·(kg·d)-1+CM 0.1 g·(kg·d)-1(CM+&CFA+)。试验期85 d,其中预试期15 d,正试期70 d,在试验期结束前10 d开展消化代谢试验。试验结果表明:1)饲粮添加CFA显著提高了1~30 d平均日增重和饲料转化率(P<0.05),而添加CM仅显著提高了1~30 d饲料转化率(P=0.036),对1~30 d平均日增重无显著影响(P>0.05);饲粮中添加CFA、CM显著提高了杜寒杂交二代公羔31~60 d和1~60 d平均日增重及相应阶段饲料转化率(P<0.05),二者对1~60 d饲料转化率具有显著互作效应(P=0.007);2)饲粮添加CFA显著提高了干物质、有机物、中性洗涤纤维和酸性洗涤纤维的表观消化率(P<0.05),饲粮添加CM有提高有机物表观消化率的趋势(P=0.066)及增加干物质消化率的趋势(P=0.095),二者对养分消化率无显著互作效应(P>0.05);3)饲粮添加CFA、CM显著降低了尿能排出量,显著提高了能量消化率和代谢率(P<0.05);通过显著降低粪氮、尿氮及总排泄氮(P<0.05),从而显著提高了氮的表观消化率和沉积氮水平(P<0.05),且二者同时添加对减少氮排泄、提高氮消化率有显著互作效应(P<0.05);4)饲粮添加CM、CFA显著提高嘌呤衍生物的尿排泄量,提高瘤胃微生物蛋白质合成量(P<0.05)。饲粮添加CM、CFA提高干物质和有机物表观消化率,改善总能消化率和代谢率,增加氮表观消化率和氮沉积量,促进杜寒杂交二代公羔的生长。  相似文献   
6.
7.
A total of 630 juvenile Chinese sucker, with an average initial weight of 1.72 ± 0.05 g, were fed seven diets for 56 days to study the effect of dietary methionine levels on growth, feed utilization, body composition and haematological parameters on juvenile Chinese sucker. Diet 1 using fish meal as the sole protein source and diets 2–7 using fish meal and fermented soybean meal as intact protein sources supplemented with crystalline amino acids contained six levels of l ‐methionine ranging from 6.4 to 18.9 g kg?1 of dry diet at a constant dietary cystine level of 3.7 g kg?1. Each diet was randomly assigned to three aquaria. Results indicated that the highest weight gain, specific growth rate (SGR), feed efficiency ratio, protein efficiency ratio and protein productive value occurred at 13.9 g methionine kg?1 diet among the methionine supplemented dietary groups, beyond which they showed declining tendency. The whole body and muscle protein contents of juvenile Chinese sucker were positively correlated with dietary methionine level, while muscle lipid content was negatively correlated with it. The total essential amino acids content of muscle was increased significantly with increasing dietary methionine level from 6.4 to 13.9 g kg?1 (< 0.05). Apparent digestibility coefficients of dietary protein were significantly affected by dietary treatments. Serum protein, cholesterol and triacylglycerol increased with increasing dietary methionine levels, but showed a relatively lower value for fish fed the 18.9 g methionine kg?1 diet. Quadratic regression analysis of SGR against dietary methionine level indicated that optimal dietary methionine requirement for juvenile Chinese sucker was 14.1 g kg?1 of the diet in the presence of 3.7 g kg?1 cystine (corresponding to 32.0 g kg?1 of dietary protein on a dry‐weight basis).  相似文献   
8.
Methionine–choline‐deficient (MCD) mammals are known to accumulate liver TAG probably due to phosphatidylcholine (PC) deficiency and thus assembly of VLDL and transport of lipids from liver to peripheral organs. To assess whether supplementation of choline could spare methionine and secure a healthy liver metabolism, by reducing the endogenous PC synthesis without interfering with lipid transport and distribution, Atlantic salmon with initial BW of 700 g were fed adequate (1.9 g Met/16 gN) or surplus methionine (2.5 g Met/16 gN) diets of which were supplemented with choline or not for a period of 19 weeks. Fish fed the low‐methionine diets had reduced growth (p = .013) due to reduced protein gain (p = .007), while lipid gain slightly improved in fish fed the choline‐supplemented diets (p = .047). Also, feed conversion improved when fed surplus methionine (p < .001), while choline supplementation had no impact on feed conversion. No interaction between choline and methionine on growth performance or retention existed. Phospholipid status in liver and muscle was not affected by treatments, and no liver TAG accumulation occurred at the methionine levels used. Gene expression of ApoB100 necessary for assembling VLDL or pemt necessary for endogenous PC synthesis was unaffected by treatments. Capacity of methylation (MAT, BHMT) within the liver was not affected by treatment nor was the gene expression of enzymes in liver transsulfuration (CBS or CDO). Methionine status within liver was unaffected by treatments, while free methionine reduced in those fish fed the low‐methionine diets in muscle and plasma. Cystathionine and taurine were elevated when fed surplus methionine. Choline supplementation had no impact on sulphur amino acid metabolites in either tissue. Neither did choline supplementation improve TAG mobilization from liver to muscle. To conclude, choline does not improve endogenous phospholipid synthesis or transport of TAG from liver to muscle depot when added to diets containing 1.9 g Met/16 gN, while surplus methionine improved growth and protein retention, indicating that 1.9 g Met/16 gN is enough to support a healthy liver metabolism, but too low to support muscle protein deposition in adult salmon fed high plant protein diets for longer periods of time.  相似文献   
9.
Plant protein‐based diets are widely used for common carp (Cyprinus carpio var. Jian). The plant source antagonist, such as phytate, negatively affects the bioavailability of trace minerals, but this aspect was not considered in previous studies on this species. A 10‐week growth trial was conducted to investigate the effects of inorganic Zinc (ZnSO4·7H2O, Zn‐S) and organic Zn (2‐hydroxy‐4‐(methylthio) butanoic Zinc, Zn‐M) on growth performance, Zn retention and antioxidant responses of common carp (initial weight 10.0 ± 0.03 g). Eleven semi‐purified diets containing 7 mg/kg phytic acid were prepared with 0, 5, 20, 35, 50 and 65 mg/kg Zn from Zn‐S and Zn‐M (12.8 mg/kg Zn in basal level), respectively. The results showed that either Zn‐S or Zn‐M inclusion improved growth performance, vertebral Zn deposition and antioxidant responses of fish. The Zn requirement based on WGR, vertebrae Zn and plasma SOD were 47.0, >77.8 and 48.5 mg/kg, and 63.3, 42.2 and 36.8 mg/kg, respectively, with Zn‐S and Zn‐M as Zn sources. The relative bioavailability of Zn‐M was 2.44‐ (vertebrae Zn deposition) and 1.74‐fold (plasma SOD activity) the availability of Zn‐S in the diet of common carp. The lower growth performance and poor bioavailability in vertebrae of Zn‐S group were related to the chelating of zinc with phytic acid.  相似文献   
10.
为研究日粮添加过瘤胃氨基酸对泌乳早期奶牛生产性能、乳成分、血液生化指标和经济效益的影响,选择96 头体况良好、健康的泌乳早期荷斯坦牛,泌乳天数为(65±15)天。采用单因素随机区组试验设计,按照年龄、胎次和产奶量相近的原则,将96 头奶牛随机分为对照组和试验组,每组48 头。对照组为基础日粮,试验组在对照组日粮的基础上添加过瘤胃蛋氨酸(RPMet)和过瘤胃赖氨酸(RPLys),添加量分别为18 g/头·天和35 g/头·天。结果表明,与对照组相比,添加RPMet和RPLys显著提高产奶量(P=0.034),对干物质采食量和饲料转化率无显著影响(P>0.050);添加RPMet和RPLys显著降低乳尿素氮含量(P=0.015),对乳脂率有增加的趋势(P=0.096),对乳蛋白率、乳体细胞数、乳糖率和总固形物含量无显著影响(P>0.050);添加RPMet和RPLys显著提高血清总蛋白(TP)、白蛋白(ALB)和血糖(GLU)含量,显著降低尿素氮(BUN)含量(P=0.049),对谷丙转氨酶(ALT)、谷草转氨酶(AST)、球蛋白(GLOB)、碱性磷酸酶(ALP)、甘油三酯(TG)和总胆固醇(TC)含量无显著影响(P>0.050);添加RPMet和RPLys可提高经济效益3.60 元/头·天。综上所述,日粮添加RPMet和RPLys可提高泌乳早期奶牛的产奶量,增加经济效益。  相似文献   
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