Functional characteristics of the blood of the deep-sea hydrothermal vent brachyuran crab

Hemocyanin in the whole blood of the hydrothermal vent brachyuran crab, Bythograea thermydron, has a moderate oxygen affinity (P(50) = 6.6 millimeters of mercury at 2.6 degrees C; pH 7.5), which unlike that of other hemocyanins is independent of temperature over the range 2 degrees to 30 degrees C; carbon dioxide and pH have independent effects on the oxygen affinity of this pigment. The pH effect on affinity is moderate (Deltalog P(50)/DeltapH = -0.34), whereas increased carbon dioxide, which can act both directly and by changing pH, has a much larger effect (Deltalog P(50)/DeltapH = -0.81). This blood has a moderately high degree of cooperativity (Hill cooperativity coefficient, n, was 2.8) and a large oxygen-carrying capacity for a crustacean (4.5 milliliters of oxygen per 100 milliliters of blood). These properties characterize an oxygen transport system whose function appears to be largely independent of the wide range of environmental conditions encountered around the vents.     

营养水平和饲粮组合对育肥羔羊生产及屠宰性能的影响

按同质原则将 28 只试羊(3~3.5 月龄)分为 4 个饲粮处理组,采用 3 因子(2×2×2)设计,研究两个营养水平(A 因子,A1—0.9NRC 和 A2—0.8NRC)下不同饲粮组合(B 因子,B1—添加甜菜渣和 B2—不添加甜菜渣)对不同杂交组合(C 因子,C1—波德代(♂)×蒙古羊(♀),C2—陶塞特(♂)×蒙古羊(♀))的育肥效果。结果表明,A、B、C 三因子对试羊平均日增重均无显著影响(P>0.05),仅正试期头 20 dC2日均增重显著(P<0.05)高于 C1。A1水平羔羊平均日采食量极显著(P<0.01)低于 A2,而饲料转化率及熟肉率极显著(P<0.01)高于 A2。B1正试期后 40 d 日均增重有高于 B2的趋势,而 GR 值有低于 B2的倾向。     

大体积日粮对母猪及其繁殖性能的影响

研究了大体积高纤维日粮对母猪的影响,试验分为A组(对照组)和B组(试验组),两组的粗纤维含量分别为3.87%,12.56%.A组便秘发生率为60%,B组5%(P＜0.05),A组平均产活仔数9.69头,初生窝重10.7kg,,B组10.08头,11.59kg(P＞0.05);从分娩到仔猪20日龄期间,A组日平均采食量4.48kg,B组4.61kg(P＜0.05);仔猪20日龄成活率及平均窝重A组分别为94.84%、44.30kg,B组95.04%、47.04kg(P＜0.05);断奶后的发情间隔A组平均为8.9天,B组5.4天,缩短了3.5天(P＜0.05).说明添加粗纤维能有效解决母猪的便秘问题,同时对其产仔数和窝重不仅无不良影响,而且有改善趋势;在哺乳期母猪食欲好,采食量大,因此仔猪在20日龄的成活率及窝重B组略优于A组;B组断奶后的发情间隔较A组缩短了3.5天.总之,饲喂大体积日粮对生产有益.     

日粮中添加生物发酵饲料对生长育肥猪生产性能的影响

本试验选用杜洛克×长白×大约克三元杂交健康生长育肥猪30头,按体重、窝别等随机分为3组,分别饲喂含0%、20%和30%发酵饲料的全价日粮,对育肥猪的生产性能进行研究。结果表明:在生长育肥猪的基础日粮中添加发酵饲料能提高育肥猪的日增重和饲料转化率,发酵饲料以30%的添加量效果较佳。     

黑麦草颗粒饲料对扬州鹅生产性能与器官生长的影响

【目的】研究黑麦草粉颗粒饲料对扬州鹅生长性能、屠宰性能和器官的影响。【方法】选择体质量相近(出壳时间和体质量基本一致)、健康的扬州鹅300只,将其随机分为对照组和试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组共5组,每组3个重复,每个重复20只,分别饲喂黑麦草粉添加量(质量分数)依次为0(CK),12%,16%,20%和24%的日粮21d后,测定试鹅的各项生长性能和屠宰性能指标。【结果】Ⅱ和Ⅲ组试验终末体质量、平均日采食量和平均日增质量显著高于对照组(P0.05),而料质量比低于对照组(P0.05);试验Ⅲ组宰前活质量、屠体质量、半净膛质量、全净膛质量、腿肌质量、腿肌率、胫骨质量和胸肌质量均显著高于对照组(P0.05),试验Ⅱ组的腹脂质量最低,各处理组之间的屠体率、半净膛率、全净膛率、腹脂率和胸肌率差异不显著(P0.05);试验Ⅱ组的肝质量、腺胃质量和胸腺质量显著高于对照组(P0.05),而试验Ⅲ和Ⅳ组的肌胃质量和胰腺质量显著高于对照组(P0.05),各试验组的心质量均高于对照组,但各试验组间差异均不显著(P0.05)。试验Ⅲ组的空肠、盲肠、回肠长度以及肠道总长均显著大于对照组(P0.05)。【结论】添加不同水平的黑麦草粉颗粒饲料均能够在一定程度上提高扬州鹅的生长性能和屠宰性能,促进肠道生长,且以添加量为20%时效果最好。     

罗氏沼虾雌虾规格对生殖性能和胚胎质量的影响

为了解罗氏沼虾(Macrobrachium rosenbergii)雌虾体质量对其生殖性能和胚胎质量的影响,本研究比较了4种规格（A组：16~20 g/尾、B组：24~28 g/尾、C组：32~36 g/尾、D组：40~44 g/尾）的雌虾亲本的生殖性能、胚胎质量和胚胎色泽,以及分析了体质量和生殖性能之间的相关性. 结果显示：随着雌虾体质量的增加,雌虾抱卵量呈显著上升趋势,D组的抱卵量显著高于A、B、C组的抱卵量,C组显著高于A组(P<0.05),生殖力和生殖指数也随着体质量的增加而呈上升,D组显著高于A组(P<0.05),但是A、B、C组之间无显著性差异,B、C、D组之间无显著性差异;各组之间的单卵湿质量、单卵干质量和卵径均无显著性差异;各组之间的胚胎色泽参数均无显著性差异;体质量与抱卵量（r=0.847, P=0.000）、生殖力（r=0.508, P=0.004）和生殖指数（r=0.551, P=0.001）均呈显著正相关. 结果表明,大规格罗氏沼虾的生殖性能优于小规格,但是规格对胚胎质量无明显的影响,该研究为罗氏沼虾亲本选择、生殖性能评价和人工育苗提供了重要基础资料     

小肽营养素对奶牛泌乳性能的影响

选择中国荷斯坦泌乳牛32头,随机分成4组,A组(对照组)为基础精料日粮组,B、C、D组为基础精料日粮分别添加0.1%、0.3%和0.5%小肽营养素处理组.预试期7 d,正式试验28 d.试验结果表明:添加0.1%、0.3%、0.5%小肽营养素处理组,每头奶牛日平均产奶量比对照组分别增加1.21 kg、1.50 kg、1.43 kg,且差异达极显著(P<0.01);添加小肽营养素后,牛奶中乳蛋白和乳脂率均有所提高,但差异不显著(P>0.05),有随小肽营养素添加量的增加而提高的趋势;添加0.1%、0.3%、0.5%小肽营养素处理组,每头奶牛平均日净增效益分别为2.51元、2.85元和2.40元.从生产性能和经济效益综合考虑,以基础精料中添加0.1%～0.3%小肽营养素为宜.     

高温胁迫对不同规格褐牙鲆生长性能的影响

以25℃为对照组,设置28℃、30℃、32℃为高温胁迫组,采用实验生态学方法研究高温胁迫对2种规格(实验I和实验II)的褐牙鲆幼鱼生长的影响。结果显示:(1)水温25~30℃时,褐牙鲆几乎不死亡;水温达到32℃时,褐牙鲆的成活率显著下降,2种规格鱼在32℃下的成活率无显著差别(P<0.05);(2)两种规格鱼的生长性能受水温影响显著,各温度处理组的特定生长率、摄食率和饵料转化率和水温的平方呈显著的负相关(One-way ANOVA,P<0.01);(3)相同温度条件下,实验Ⅰ的特定生长率和摄食率显著高于实验Ⅱ(P<0.05),饵料转化率则实验Ⅰ显著低于实验Ⅱ(P<0.05),表明规格大小对褐牙鲆的生长性能具有显著影响。本研究结果表明,32℃可能是褐牙鲆长期生存的上限温度,高温胁迫和规格大小显著影响褐牙鲆的生长性能。研究亮点:采用不同的温度梯度对2种规格褐牙鲆进行高温胁迫,系统比较不同温度下2种规格鱼的存活率、生长率及摄食率和食物转化率的差异,确定褐牙鲆长期生存的临界上限温度,以期为其健康养殖提供参考资料。     

Effects of organic chromium supplementation to ifnishing lambs diet on growth performance,carcass characteristics and meat quality

The objective of this study was to evaluate supplemental organic chromium (Cr) to ifnishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs (age (4.5±0.2)...     

Effects of organic chromium supplementation to finishing lambs diet on growth performance,carcass characteristics and meat quality

The objective of this study was to evaluate supplemental organic chromium(Cr) to finishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs(age(4.5±0.2) mon;(25.8±3.6) kg body weight(BW)) were randomly assigned to three levels of supplemental organic Cr(0.0, 0.2 and 0.4 mg kg–1 dry matter(DM)) in a complete random design. Growth performance was evaluated for 70 d, and then lambs were slaughtered to study carcass characteristics and chemical composition of meat. Orthogonal contrasts were performed(contrast one-average level 0.2 ppm Cr vs. average level 0.4 ppm Cr; contrast two-level 0 vs. average levels(0.2+0.4) ppm Cr). Orthogonal polynomials were used to estimate the linear and quadratic effects of Cr concentrations. Growth and carcass performance were not affected by supplemental organic Cr. Muscle conformation and leg perimeter linearly increased(P0.05) as organic Cr level increased in the diet. Kidney fat decreased linearly(P0.05) as supplemental Cr increased. In Longissimus dorsi(LD), the ash content decreased linearly, and shear force(kg cm–2) increased(P0.05) as organic Cr level increased in the diet. It is concluded that organic Cr did not affect growth performance, but it improved positively the muscle conformation, reduced kidney fat, whereas in LD there was an increment in shear force in finishing carcass lambs.     

Effects of organic chromium supplementation to finishing lambs diet on growth performance,carcass characteristics and meat quality

The objective of this study was to evaluate supplemental organic chromium(Cr) to finishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs(age(4.5±0.2) mon;(25.8±3.6) kg body weight(BW)) were randomly assigned to three levels of supplemental organic Cr(0.0, 0.2 and 0.4 mg kg–1 dry matter(DM)) in a complete random design. Growth performance was evaluated for 70 d, and then lambs were slaughtered to study carcass characteristics and chemical composition of meat. Orthogonal contrasts were performed(contrast one-average level 0.2 ppm Cr vs. average level 0.4 ppm Cr; contrast two-level 0 vs. average levels(0.2+0.4) ppm Cr). Orthogonal polynomials were used to estimate the linear and quadratic effects of Cr concentrations. Growth and carcass performance were not affected by supplemental organic Cr. Muscle conformation and leg perimeter linearly increased(P<0.05) as organic Cr level increased in the diet. Kidney fat decreased linearly(P<0.05) as supplemental Cr increased. In Longissimus dorsi(LD), the ash content decreased linearly, and shear force(kg cm–2) increased(P<0.05) as organic Cr level increased in the diet. It is concluded that organic Cr did not affect growth performance, but it improved positively the muscle conformation, reduced kidney fat, whereas in LD there was an increment in shear force in finishing carcass lambs.     

Effect of trimming claws on livability and productivity of caged chickens

The effect of trimming claws at an age of one day on the growth, development, livability, and production of laying chickens housed in cages is studied. It is established that trimming the claws of the middle and posterior toes compared to the control considerably reduces the age of sexual maturity of poultry and increases livability of the flock, egg production, and egg mass yield per hen with decrease of feed consumption per unit product.     

玉米-菜粕型日粮中添加钠化合物对蛋鸡生产性能的影响

在含硫氨基酸和赖氨酸水平较低的玉米-菜粕型日粮中分别添加0.3%硫酸钠、0.3%碳酸氢钠、0.3%硫酸钠+0.3%碳酸氢钠，能提高伊莎褐蛋鸡产蛋率、蛋重及饲料利用率，使产蛋饲料成本下降，盈利值明显增加，对存活率则无影响。其中尤以混合添加组效果最佳，其次分别为碳酸氢钠组和硫酸钠组。研究还发现，日粮中添加碳酸氢钠，能明显增加蛋鸡的蛋壳厚度（P＜0.05），蛋壳强度也有显著提高（P＜0.05）。     

添加不同剂型植酸酶颗粒料对仔猪生产性能和血液生化指标的影响

【目的】探讨在仔猪颗粒料中添加植酸酶对仔猪生产性能与血液生化指标的影响。【方法】将224头杜洛克×长白×大约克三元杂交仔猪随机分为对照组和试验A、B、C组,对照组饲喂颗粒料(制粒温度为83℃),试验A、B、C组分别饲喂以粉状、颗粒状和液体植酸酶代替1/2磷酸氢钙(另1/2磷酸氢钙用石粉和载体代替)的颗粒料,酶的添加量为100 g/t或100 m/t,试验期为30 d。试验前后分别测定生产性能和血液生化指标。【结果】与对照组比较,B和C组平均日增重分别提高5.30%和6.14%(P<0.05),料重比分别降低3.08%和4.10%(P<0.05),白蛋白含量分别提高17.05%和21.38%(P<0.05),球蛋白含量分别提高18.81%和23.73%(P<0.05),总蛋白含量分别提高9.94%和15.81%(P<0.05),碱性磷酸酶、总胆固醇、丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、血红蛋白、血清钙和血清磷等含量较对照均有所增加,但差异不显著(P>0.05);试验A组与对照组各项指标差异均不显著(P>0.05)。【结论】在制粒温度不超过83℃时,仔猪颗粒料中添加颗粒型和液体型植酸酶,可提高仔猪的生产性能和血液生化指标。     

低蛋白饲粮中添加复合酶与益生素对肉仔鸡生长性能及养分利用率的影响

选择1日龄艾维茵肉仔鸡80只,随机分为2个处理组,每个处理组4个重复。处理组1为基础日粮添加0.01%吉他霉素;处理组2为粗蛋白质水平比基础日粮低2个百分点的基础上,添加0.16%复合酶制剂和0.2%益生素。结果表明,与添加抗生素相比,在降低蛋白质水平的同时添加复合酶和益生素,不但没有显著降低肉仔鸡的平均日增重和料重比(P>0.05),还显著提高了饲料粗蛋白质、粗脂肪、钙和总磷的表观利用率(P<0.05)。     

Effects of size and temperature on metabolic rate

We derive a general model, based on principles of biochemical kinetics and allometry, that characterizes the effects of temperature and body mass on metabolic rate. The model fits metabolic rates of microbes, ectotherms, endotherms (including those in hibernation), and plants in temperatures ranging from 0 degrees to 40 degrees C. Mass- and temperature-compensated resting metabolic rates of all organisms are similar: The lowest (for unicellular organisms and plants) is separated from the highest (for endothermic vertebrates) by a factor of about 20. Temperature and body size are primary determinants of biological time and ecological roles.     

改变日粮蛋白质和赖氨酸含量对奶牛产奶性能和氮利用及代谢激素的影响

为观察不同日粮蛋白质(CP)和赖氨酸(Lys)含量对奶牛产奶性能、氮利用和血液代谢激素的影响,试验采用4×4拉丁方设计,选择4头经产中国荷斯坦奶牛,随机接受4种日粮处理:12.5%CP和0.44%Lys的Et粮1;12.6%CP和0.58%Lys的日粮2;14.1%cP和0.45%Lys的日粮3;14.1%CP和0.60%Lys的日粮4.试验分为4期,每期18 d.第1天至第14天为适应期,第15天至第18天为收集期.结果表明:日粮4和日粮2的产奶最显著高于日粮3和日粮1(P<0.05).乳蛋白率也略高于日粮3和日粮1(P>0.05);日粮4和日粮2的氮利用率和奶氮排出量明显高于日粮3和日粮1(P<0.05):日粮4和日粮2的尿素氮(SUN)浓度明显低于日粮3和日粮1(P<0.05);日粮4和日粮2的胰岛素和催乳素浓度明显高于日粮3和日粮1(P<0.05).赖氨酸含量相同时,日粮CP含量为14.1%或12.6%,奶牛产奶性能不受影响,乳氮产量增加,氮利用率提高;当奶牛日粮赖氨酸含量从0.60%降到0.45%,尽管蛋白质含量相同,但奶牛产奶量下降,乳蛋白略呈下降趋势,乳氮产量降低,氮利用率降低.     

饲料添加螺旋藻对克氏原螯虾生长性能的影响

在克氏原螯虾饲料中设置了0～8%共6个梯度的螺旋藻添加量,投喂成年及幼年虾,并测定其各项生长性能指标.试验结果表明:(1)适量螺旋藻能促进螯虾生长,2%螺旋藻添加量对成虾增重率和不同虾龄螯虾的含肉率提升作用最为明显;4%螺旋藻添加量对幼虾增重率和不同虾龄螯虾的SOD提升作用最为明显.(2)螺旋藻对幼虾生长性能多项指标的提高作用优于成虾,而成虾仅增重率相对提高比较大.(3)建立了成虾和幼虾增重率(yw)、SOD(yS)和含肉率(yr) 与螺旋藻添加量(x)的函数模型,结果表明模型均呈良好的抛物线关系.(4)函数解析结果表明:使成虾增重率、含肉率和SOD达最大值的螺旋藻添加量分别为4.00%、2.41%、4.46%;使幼虾增重率、含肉率和SOD达最大值的螺旋藻添加量分别为5.12%、2.23%、4.46%.     

低磷日粮中添加植酸酶对蛋鸡产蛋性能、内源消化酶及养分消化率的影响

为探明在低磷的玉米一豆粕型日粮中添加植酸酶对蛋鸡产蛋性能、内源消化酶及养分消化率的影响,该研究选用18周龄体重、产蛋周龄相近的伊莎褐蛋鸡840羽,随机分成7组:对照1( Ⅰ组,基础日粮,未添加植酸酶)、对照2(Ⅱ组,有效磷水平降低0.12个百分点)及在对照2基础上分别添加300 U/kg、1 000 U/kg和10 0...     

日本蟳形态性状对体重的影响效果

随机选取莱州湾日本蟳Charybdis japonica野生个体96只,分别测量了其额宽(X1)、甲长(X2)、甲宽(X3)、体高(X4)、全甲宽(X5)、大螯不动指高(X6)、大螯长节长(X7)、大螯不动指宽(X8)、大螯不动指长(X9)、第一步足长节高(X10)、第一步足长节长(X11)、第一侧齿间距(X12)、第二侧齿间距(X13)、体重(Y)共14个形态学指标。采用相关分析和通径分析的方法,计算了以形态性状为自变量对体重作因变量的相关系数、通径系数、决定系数及相关指数,定量分析了形态性状对体重的影响效果。结果表明:日本蟳的14个形态性状与体重的相关系数达到极显著水平(P<0.01);通径分析揭示了多元分析中多个自变量与因变量的真实关系,甲长、甲宽、第二侧齿间距对体重的通径系数达到显著水平,是直接影响体重的重要指标,其中甲长对体重的直接影响(1.060**)最大,是影响体重的最主要因素,而第二侧齿间距对体重的直接影响是反向的;决定分析的结果与通径分析结果的变化趋势一致。所选形态性状与体重的复相关指数为R2=0.886,说明影响体重的主要自变量指标已经找到;通过多元回归分析,建立了甲长、甲宽、第二侧齿间距对体重的回归方程Y=10.028X2+1.962X3-3.662X13-330.271,为日本蟳的育种提供了理想的测度指标。