瘤胃补充保护蛋氨酸和十二指肠灌注蛋氨酸对奶牛生产性能的影响

以泌乳中后期奶牛为试验对象，研究了瘤胃补充保护蛋氨酸及十二指肠灌注蛋氨酸对生产性能、乳成分及氮代谢的影响，结果表明：瘤胃补充保护蛋氨酸及十二指肠灌注蛋氨酸能显著增加血浆尿素氮、血浆甘油三酯、奶中尿素氮浓度（P〈0．05），对产奶量、乳成分、瘤胃液氨氮、血浆葡萄糖无显著影响（P〉0．05）。     

蛋氨酸羟基类似物在反刍动物中的研究与应用

蛋氨酸羟基类似物是一种重要的蛋氨酸来源,在动物生产中具有广阔的应用前景。笔者概述了蛋氨酸羟基类似物的概念,及其在反刍动物体内的代谢和在生产中的应用研究。     

不同蛋氨酸水平对长毛兔产毛性能和血液生化指标的影响

48只彩色长毛兔随机分成4个处理,处理组1为对照组,处理组2、3、4为试验组,试验组分别添加不同水平的蛋氨酸,旨在研究不同蛋氨酸水平对长毛兔产毛性能和血液生化指标的影响.试验结果:处理组2的TP、Alb、GPT、GOT、CHO、ALP、生长速度、兔毛抗拉力、韧性、密度与其他3个处理组差异显著(P＜0.05),处理组2兔毛直径较其他3个处理组大,差异显著(P＜0.05).日粮中添加0.2%蛋氨酸时,家兔的产毛性能达到最佳.     

日粮蛋氨酸、赖氨酸水平对皖西白鹅种鹅繁殖力的影响

将蛋氨酸水平 ( 0 2 1%、0 3 6%、0 5 1% )与赖氨酸水平 ( 0 49%、0 64 %、0 79% )组成 9个组合 ,探讨其对皖西白鹅种鹅繁殖力的影响。结果发现 :①蛋氨酸影响着除受精率以外的所有繁殖力指标 (P <0 0 1) ;②赖氨酸只影响产蛋量 (P <0 0 5 ) ;③ 0 3 6%的蛋氨酸与 0 64 %的赖氨酸组合 ,能最佳发挥皖西白鹅种鹅的繁殖性能。     

蛋氨酸、赖氨酸水平对皖西白鹅繁殖力的影响

将蛋氨酸水平(0.21%、0.36%、0.51%)与赖氨酸水平(0.49%、0.64%、0.79%)组成9个组合,探讨其对皖西白鹅种鹅繁殖力的影响,结果发现:蛋氨酸影响着除受精率以外的所有繁殖力指标(P<0.01);赖氨酸只影响产蛋量(P<0.05);0.36%的蛋氨酸与0.64%的赖氨酸组合,能最佳发挥皖西白鹅种鹅的繁殖性能。     

金属蛋氨酸络合物对荷斯坦牛增重的影响

8头荷斯坦公牛随机分为试验组（日粮添加金属蛋氨酸络合物）和对照组（日粮添加微量元素硫酸盐），供试日粮主营养水平完全相同，正试期90天。结果：试验组比对照组日增重提高8．91％，差异显著（P＜0．05）。     

蛋氨酸羟基类似物相对生物学效价影响因素的研究进展

本文从蛋氨酸及其羟基类似物的水解、吸收、转化、日粮中(半)胱氨酸和蛋氨酸比例及统计方法这5个方面对蛋氨酸羟基类似物相对于蛋氨酸的生物学效价的影响进行了简析并对未来的研究方向提出了建议.     

Co60γ射线照射技术在阿维菌素产生菌诱变育种中的应用

为了筛选获得阿维菌素总效价及有效组分Bla含量高的阿维链霉菌突变株,应用Co60γ射线照射并结合甲硫氨酸筛选模型和5-氟尿嘧啶筛选模型对出发菌株阿维链霉菌H20-16进行诱变处理,使用高效液相色谱法检测发酵单位与有效组分B1a的含量.通过筛选获得发酵单位提高的菌株Co3-15和CF(20)-39-61,比出发菌株分别提高了173.3%、76.5%;Bla组分提高的菌株Co35-9和CM35-12,比出发菌株分别提高了12.1%、16.7%.从而得出,利用Co60γ射线照射并结合甲硫氨酸和5-氟尿嘧啶筛选模型诱变处理阿维菌素产生菌,诱变效果显著.     

Protein quality traits of vegetable and field peas: Varietal differences

Four high yielding varieties of field (Rachna and RFP₄) and vegetable peas (Bonnivielle and Arkal) were studied for their protein quality. Crude protein and true protein content of all four pea varieties varied from 19.5 to 20.6 percent and 18.7 to 19.8 percent, respectively. Non protein nitrogen formed only 3.94 to 4.84 percent of total nitrogen. Globulins were the major fractions followed by albumins and glutelins. All the four varieties of peas had similar methionine and tryptophan content. Lysine content of four pea varieties ranged from 7.56 to 9.65 g per 16 g of N. Cooking brought about an increase in in vitro protein digestibility of peas by 10 percent. The sodium dodecyl polyacrylamidegel electrophoresis of total protein revealed the presence of 22–25 bands with some difference in banding pattern of all four varieties. Some differences were observed in banding patterns of globulin and albumin of all four varieties, suggesting that composition of protein of pea varieties differed.     

Effect of DL‐methionine supplementation on the success of almost total replacement of fish meal with soybean meal in diets for hybrid tilapia (Oreochromis niloticus × Oreochromis mossambicus)

This study evaluated the effects of increasing levels of methionine (Met) supplementation on the success of almost total replacement of fish meal (FM) with soybean meal (SBM) in diets for hybrid tilapia (Oreochromis niloticus × Oreochromis mossambicus). Fish were fed for 70 days a FM‐based diet (Diet1‐positive control) or SBM‐based diets supplemented with graded levels of DL‐methionine (Diet2 to Diet7). Contrast in dietary Met, concentration was created by supplementing Diet2‐negative control with 1.2 (Diet3), 2.4 (Diet4), 3.6 (Diet5), 4.8 (Diet6) or 6.0 g kg^?1 (Diet7) of DL‐Met. Specific growth rate (SGR), feed conversion ratio (FCR), and protein gain and retention efficiency (PER) improved significantly with increasing levels of dietary DL‐Met supplementation. Moreover, nonlinear regression analysis of the effects of supplementing SBM‐based diet with graded levels of DL‐Met indicated that a dietary Met + Cys level of 15.7 and 12.5 g kg^?1 diet (as fed) was required to reach 95% of maximum weight and protein gain, respectively. Supplementation of SBM‐based diet with graded levels of DL‐Met proved an effective strategy in reducing FM content in practical diets for hybrid tilapia. Data also indicate that adjustment of dietary formulas according to currently recommended Met or Met + Cys dietary concentrations is probably limiting maximum growth potential of hybrid tilapia.