Measurement of endogenous amino acid losses in poultry     

P. Siriwan  W. L. Bryden  Y. Mollah  E. F. Annison 《British poultry science》1993,34(5):939-949

1. Ileal endogenous amino acid losses were determined in broiler chickens and in cannulated cross‐bred layer strain cockerels using either a nitrogen‐free diet, regression analysis or a 48 h fast.

2. Endogenous amino acid flows to the ileum in fasted cockerels were significantly lower than those obtained both by feeding the nitrogen‐free diet, and from regression analysis in either broilers or cockerels. Regression analysis gave the highest flows.

3. The apparent digestibility coefficients of amino acids in a diet containing 200 g/kg crude protein were lower in broilers (0.84) than in cockerels (0.88). When corrected, by regression analysis, for the contribution of endogenous amino acids, the true digestibility coefficients became 0.90 and 0.92 respectively.  相似文献   

Altered adenosine triphosphatase activities in pigs with naturally occurring hypertrophic cardiomyopathy     

K-S. Dai  C-S. Liang  Y. T. Ch'iu  P-C. Yang  I. C. Cheng 《Veterinary research communications》1995,19(2):115-125

The purpose of this study was to determine whether myocardial adenosine triphosphatase (ATPase) activities were reduced in pigs with naturally occurring hypertrophic cardiomyopathy (HCM). The selection of hearts for the HCM and the normal control groups depended on histological examination. Specific ATPase activity and 5-nucleotidase activity were measured in left ventricular myocardium obtained from HCM (n=7) and normal control (n=7) animals. The histological features of HCM included marked disorientation of muscle cells, thickening of the intramural coronary arterial wall with a narrowed lumen, endocardial fibrosis and myocardial fibrosis. The HCM group showed significant increases in both heart weight (32%) and heart weight to body weight ratio (46%). The total ATPase activity in crude homogenates from the HCM group was significantly decreased by 16%. Azide-sensitive ATPase (mitochondrial ATPase) activity, ouabain-sensitive ATPase (Na⁺,K⁺-ATPase) activity, basal Mg²⁺-ATPase activity and Ca²⁺-ATPase activity were all significantly decreased by 18%, 30%, 20% and 50%, respectively. In contrast, no significant decrease was found in the mean values for 5-nucleotidase activity. These results suggest that myocardial ATPase activities are suppressed in pigs with naturally occurring HCMAbbreviations ATP adenosine triphosphate - gww grams wet weight - HCM hypertrophic cardiomyopathy - Pi inorganic phosphate  相似文献   

The relative growth of internal organs in light and heavy breeds     

Y. Dror  I. Nir  Zafrira Nitsan 《British poultry science》1977,18(4):493-496

1. The relative weights of the gastrointestinal segments and of some other internal organs from light and heavy breed chicks from hatching to 21 days of age were compared.

2. The relative weight of the duodenum and jejunum was higher in the light breed than in the heavy one, the reverse relationship was found for the ileum and caecum.

3. The relative growth of the pancreas, heart, cerebrum and cerebellum was greater in the light breed.  相似文献   

Pathology of naturally occurring vitamin D3-deficient rickets in growing broiler chickens in Japan.     

C Itakura  M Takechi  Y Miyakawa  M Goto 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1979,41(5):517-530

  相似文献   

西藏的小麦白秆病     

徐雍皋 《植物保护学报》1979,6(2):25-33,66

小麦白秆病是在青藏高原上为害小麦的一种新病害,在受害的叶、叶鞘及茎秆上产生草黄色条斑和椭圆形至长方形斑点两种症状。经鉴定病害由壳月孢属(Selenophoma)真菌引起。病菌在15℃黑暗条件下的马铃薯葡萄糖琼脂上培养,形成粘质状菌落,生长缓慢,不形成分生孢子器,而在菌丝上芽殖分生孢子;在15℃黑光灯照射下的燕麦琼脂等培养基上培养,形成分生孢子器。分生孢子器分生孢子新月形,无色,单胞,大小为17.9-26×2.6-3.6μ;而芽殖分生孢子的大小及形态变异较大。病菌的生长温度范围为0—20℃,以15℃为最适宜。其寄主有小麦、黑麦及冰草等。种子和幼苗经接种后,均产生系统性条斑症状。根据病菌的形态和寄主范围,小麦白秆病菌即Selenophoma donacis(pass)sprague efA.G.Johnson,由于S.donacis 只产生斑点症状,而小麦白秆病菌产生特有的系统性条斑症状,且发生温度偏低,所以认为小麦白秆病菌是在青藏高原特殊的生境条件下,形成的一个Selenophoma donacis(pass)sprague et A.G.Johnson的“白秆(albo-culmo)生态型。  相似文献   

利用磷肥厂副产氟硅酸防治小麦锈病的研究     

屠予钦  魏岑 《植物保护学报》1979,6(1):57-70

作者于1966半报告了氟硅酸对小麦条锈病具有良好药效,氰硅酸是磷肥厂副产,资源丰富、成本低廉。1971年又用氟硅酸与尿素制成便于运输和贮存的晶态的氟硅脲,其分子式为[(NH_2)_2CO]_4·H_2SiF_6。十多年来经过15个省市的田间试验,肯定了氟硅酸和氟硅脲对小麦三种锈病均有效。在山东烟台地区和四川内江地区的大面积推广试用均取得良好效果。防治有效浓度按H_2SiF_6计为0.05～0.10%,药液中须加入湿润剂。除扬花期不可喷药外,其它生育期均可喷药。对小麦的增产效果显著。小麦种子中未发现氟的反常残留。经卫生部门测定,十个样本中有6个氟残留量为0.71～1.98ppm,有1个样本中为3.47ppm,系过量喷药所致。其余3个样本中未检出氟。本文讨论了使用无机氟剂的环境保护问题。根据地球化学和环境化学的最近研究成果,在本文所建议采取的使用浓度下,用氟硅酸防治小麦锈病并无引起环境污染之虞。  相似文献   

小麦对条锈病的水平抗病性研究初报   总被引：4，自引：0，他引：4  

曾士迈  王沛有  武修英  张万义  王吉庆  宋位中  王生元 《植物保护学报》1979,6(1):1-10

将小麦品种采用随机区组的田间设计种于小种病圃中,以鉴定和测定其水平抗性。根据各个“品种——小种”组合的相对病情指数的方差分析的结果,有些品种,如农大311、西农6028和丰产3号,其品种——小种互作高度显著,被鉴定为具有垂直抗性,另外一些品种,对试验所用的小种并无专化性,并且在大田生产中已显出20多年的持久的中度抗性,初步推测为属水平抗性。在后一类中,有些品种,如平原50,表现为中等反应型,其余则属于呈典型感病的迟锈慢锈类型。在迟锈慢锈品种的病指的对数矫正值(logits)和病圃的锈病强度(以感病对照品种的病指表之)的对数矫正值之间发现了直线回归。  相似文献   

Characteristics of the ionization tracks and interactions of uranium-238 nuclei in emulsion     

Heckman HH  Karant YJ  Friedlander EM 《Science (New York, N.Y.)》1982,217(4565):1137-1138

The acceleration and extraction of uranium-238 nuclei by the Bevalac have been confirmed by their visual detection in nuclear research emulsion. A preliminary result for the collision mean free path for stopping uranium-238 (energy 相似文献   

‘Plantibodies’: a flexible approach to design resistance against pathogens     

A. Schots  J. De Boer  A. Schouten  J. Roosien  J. F. Zil Verentant  H. Pomp  L. Bouwman-Smits  H. Overmars  F. J. Gommers  B. Visser  W. J. Stiekema  J. Bakker 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):183-191

Engineering resistance against various diseases and pests is hampered by the lack of suitable genes. To overcome this problem we started a research program aimed at obtaining resistance by transfecting plants with genes encoding monoclonal antibodies against pathogen specific proteins. The idea is that monoclonal antibodies will inhibit the biological activity of molecules that are essential for the pathogenesis. Potato cyst nematodes are chosen as a model and it is thought that monoclonal antibodies are able to block the function of the saliva proteins of this parasite. These proteins are, among others, responsible for the induction of multinucleate transfer cells upon which the nematode feeds. It is well documented that the ability of antibodies to bind molecules is sufficient to inactivate the function of an antigen and in view of the potential of animals to synthesize antibodies to almost any molecular structure, this strategy should be feasible for a wide range of diseases and pests.Antibodies have several desirable features with regard to protein engineering. The antibody (IgG) is a Y-shaped molecule, in which the domains forming the tips of the arms bind to antigen and those forming the stem are responsible for triggering effector functions (Fc fragments) that eliminate the antigen from the animal. Domains carrying the antigen-binding loops (Fv and Fab fragments) can be used separately from the Fc fragments without loss of affinity. The antigen-binding domains can also be endowed with new properties by fusing them to toxins or enzymes. Antibody engineering is also facilitated by the Polymerase Chain Reaction (PCR). A systematic comparison of the nucleotide sequence of more than 100 antibodies revealed that not only the 3′-ends, but also the 5′-ends of the antibody genes are relatively conserved. We were able to design a small set of primers with restriction sites for forced cloning, which allowed the amplification of genes encoding antibodies specific for the saliva proteins ofGlobodera rostochiensis. Complete heavy and light chain genes as well as single chain Fv fragments (scFv), in which the variable parts of the light (V_L) and heavy chain (V_H) are linked by a peptide, will be transferred to potato plants. A major challenge will be to establish a correct expression of the antibody genes with regard to three dimensional folding, assembly and intracellular location.  相似文献   

The biochemical basis of resistance of potato to soft rot bacteria     

G. D. Lyon  J. Heilbronn  R. S. Forrest  D. J. Johnston 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):127-133

Evidence is presented that a number of mechanisms are involved in the resistance of commercial cultivars of potato to soft rottingErwinia spp. These include phytoalexins, phenolics, cell wall modification, and possibly proteins. The role of elicitor-active oligogalacturonides, which are released from plant cell walls by pectic enzymes, is discussed.  相似文献