Histological studies on cow intestinal mucosa and electron microscopic studies of the ruminal epithelium of cows fed a deficient diet for a prolonged time]     

J Marcaník  J Kocisová  K Bod'a  T Pauer  M Belák  R Skarda 《Archives of Animal Nutrition》1976,26(11):757-763

Histological and histochemical studies were carried out on the gastro-intestinal mucosa of three experimental cows (roughages/maize silage) and three control animals. The animals were slaughtered on termination of the long-term trial. Mucosa samples were taken, for further study, from the rumen, the duodenum, the jejunum, the large intestine and the appendix. Histochemical analysis did not reveal any essential differences in the activities of non-specific esterase, alkaline and acid phosphatase and lactic acid dehydrogenase in the mucosa of the rumen, the large and the small intestine and the appendix of both the experimental animals and the controls. The experimental animals were found to exhibit a higher rate of glutamate-dehydrogenase activity in the ruminal mucosa and in the mucosa of the large and small intestine. A higher succinate dehydrogenase activity was observed in the ruminal mucosa of the experimental animals, relative to that of the controls, while the activity in the intestinal mucosa was decreased. Only slight changes were noted in the activity of the enzymatic systems tested. Electron microscopic studies did not reveal any differences in the ultrastructure of the epithelial cells of the ruminal mucosa in both the experimental animal and the controls.  相似文献   

Testing of the protective effect of cell-free lyophilized vaccine against Marek's disease in field trials]     

A Kozusníková  V Benda  S Kalafa  K Pribán  J Zezulák 《Veterinární medicína》1975,20(7):355-362

The protective effect of a lyophilized vaccine against Marek's disease ("Keramvac"--Pfizer), prepared from a cell-free turkey's herpesvirus (strain FC 126), was compared in field trials with losses in the group of non-vaccinated chickens. Under the indicated conditions, the vaccine had only a 50.86% effectiveness. The possible causes of the reduced vaccination effect are discussed with regard to the pathomorphological and virological findings suggesting, among others, an increased incidence of the symptoms of the classical form of Marek's disease in the population investigated.  相似文献   

Biological features and life table parameters of the mealy plum aphidHyalopterus pruni on different apricot cultivars     

M. S. Özgökçe  R. Atlıhan 《Phytoparasitica》2005,33(1):7-14

Development, survival, reproduction rate, and population growth parameters of the mealy plum aphidHyalopterus pruni (Geoffroy) (Hom.: Aphididae) were evaluated on four different apricot cultivars (Tyrinte, Sakıt, Colomer, and Bebeco) under field conditions in the Van region of Turkey. Experiments were carried out on exterior leaves of trees, 1.5–2 m above the ground. Plexiglas clip-cells (25×6 mm) with the upper side covered by muslin were used in the experiments. The mealy plum aphid performed better on Tyrinte than on the other cultivars tested. The fastest development time (first instar to adult; 9.4 days), highest daily reproduction rate (2.6 offspring/aphid/day), and highest total fecundity (48.1 offspring/aphid) were obtained on Tyrinte. The intrinsic rate of increase — a good indicator of the growth potential of a population — of individuals fed on Tyrinte was significantly greater than that of individuals fed on cvs. Colomer and Bebeco. While mean generation times (T _o ) of populations on different cultivars were close to each other, the net reproductive rate was the highest (29.45 offspring/aphid/generation) on Tyrinte and the population doubling time on Tyrinte was 18.7%, 25.2% and 26.3% faster than those of individuals on other cultivars tested. The results obtained in this study indicated that Tyrinte appeared to be the most susceptible to the mealy plum aphid among the cultivars tested. http://www.phytoparasitica.org. posting Nov. 23, 2004.  相似文献   

Pregnancy Rates in Repeat-breeder Heifers Following Multiple Artificial Inseminations during Spontaneous Oestrus     

Bhupender Singh  Fernando Saravia  Renée B?ge  Heriberto Rodríguez-Martínez 《Acta veterinaria Scandinavica》2005,46(1):1-12

Hormonal asynchronies during oestrus, related to the presence of suprabasal plasma-progesterone (P4) concentrations and a delayed ovulation, interfere with the fertility of repeat-breeder heifers (RBH). Since tubal dysfunction can occur in connection with hormonal asynchronies and constrained availability of fertile spermatozoa at the time of ovulation, the present study tested the hypothesis that frequent sperm deposition from onset of oestrus to ovulation may improve pregnancy rates in RBH. Five RBH and five virgin heifers (VH; controls) were repeatedly artificially inseminated (AI) at 6 h intervals from onset of oestrus to spontaneous ovulation. Hormone analyses revealed suprabasal P₄ concentrations and a delay in the occurrence of the luteinising hormone (LH) surge, but a normal cortisol profile in RBH. Compared with controls, RBH presented longer interval from onset of oestrus to ovulation, and therefore, received more AIs. Pregnancy rates in RBH reached control levels (60%; NS), indicating that the hypothesis might be correct. Pregnancy rates in VH were below the expected range, presumably attributed to a deleterious influence of the frequent handling. The study suggests that pregnancy rates can be improved in RBH by frequent AI in relation to spontaneous ovulation. However, this practice of repeated manipulations, while seeming not to show adverse effects, lacks practicality for routine use.  相似文献   

C-reactive protein measurement in canine saliva.     

María Dolores Parra  Fernando Tecles  Silvia Martínez-Subiela  José Joaquín Cerón 《Journal of veterinary diagnostic investigation》2005,17(2):139-144

An established time-resolved immunofluorometric assay designed for measurement of C-reactive protein (CRP) in canine blood was evaluated and validated for use in canine saliva. C-reactive protein was measured in saliva specimens from 5 healthy dogs before and after the injection of casein and in 37 dogs with different disease conditions. The analytical and functional limits of detection were 0.000053 microg/ml and 0.0091 microg/ml, respectively, and intra- and interassay coefficients of variation ranged between 6.7-9.9% and 8.5-16.5%, respectively. A recovery experiment showed no significant disagreement between detected values and expected ones, and saliva CRP concentration was measured in a linear and proportional manner. A positive correlation was found between CRP levels obtained in saliva and serum samples in the experimental (R2 = 0.76) and clinical studies (R2 = 0.70). The assay was able to detect significant differences between salivary CRP levels in healthy dogs and dogs with inflammatory processes. These results suggest that saliva can be used for CRP measurement in dogs. The use of saliva presents the advantage of an easier and less stressful sampling method for the animals, which might be performed outside of hospital environments.  相似文献   

Detection of the Defoliating Pathotype of Verticillium dahliae in Infected Olive Plants by Nested PCR   总被引：2，自引：0，他引：2  

Jesús Mercado-Blanco  Dolores Rodríguez-Jurado  Encarnación Pérez-Artés  Rafael M. Jiménez-Díaz 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(1):1-13

Spread of Verticillium wilt into newly established olive orchards in Andalucía, southern Spain, has caused concern in the olive industry in the region. This spread may result from use of Verticillium dahliae-infected planting material, which can extend distribution of the highly virulent, defoliating (D) pathotype of V. dahliae to new areas. In this study, a molecular diagnostic method for the early in planta detection of D V. dahliae was developed, aimed especially at nursery-produced olive plants. For this purpose, new primers for nested PCR were designed by sequencing a 992-bp RAPD marker of the D pathotype. The use of the specific primers and different nested-PCR protocols allowed the detection of V. dahliae pathotype D DNA in infected root and stem tissues of young olive plants. Detection of the pathogen was effective from the very earliest moments following inoculation of olive plants with a V. dahliae pathotype D conidia suspension as well as in inoculated, though symptomless, plants.  相似文献   

Differential effects of -mannose and 2-deoxy- -glucose on attempted powdery mildew fungal infection of inappropriate and appropriate ramineae     

R. J. Zeyen  W. M. Kruger  M. F. Lyngkjr  T. L. W. Carver 《Physiological and Molecular Plant Pathology》2002,61(6)

Barley, oat and wheat were used as both inappropriate hosts (IH) and appropriate hosts (AH) for three formae speciales of the fungus Blumeria graminis, the causal agent of powdery mildew disease. Treatment with either the glucose analog 2-deoxy- -glucose (DDG) or with -mannose dramatically suppressed penetration resistance in IH and to a much lesser extent in AH combinations. Other effects of DDG and -mannose were strikingly dissimilar. DDG greatly reduced localized autofluorescence at fungal attack sites on epidermal cells, and prevented hypersensitive epidermal cell death (HR). -mannose had little effect on autofluorescence or HR. DDG arrested the development of fungal haustoria and apparently prohibited biotrophy leading to secondary hyphae. -mannose allowed haustorial development and functional biotrophy leading to the production of elongating secondary hyphae. This suggests that B. graminis is in some way capable of utilizing -mannose as a carbon substrate. Results with IH combinations paralleled those of known mlo -barley responses to DDG and -mannose. Results are discussed in relation to specific physiological processes known to be influenced by either DDG or by -mannose, or by both compounds.  相似文献   

A leakiness index for assessing landscape function using remote sensing   总被引：2，自引：0，他引：2  

Ludwig  John A.  Eager  Robert W.  Bastin  Gary N.  Chewings  Vanessa H.  Liedloff  Adam C. 《Landscape Ecology》2002,17(2):157-171

The cover, number, size, shape, spatial arrangement and orientation of vegetation patches are attributes that have been used to indicate how well landscapes function to retain, not ‘leak’, vital system resources such as rainwater and soil. We derived and tested a directional leakiness index (DLI) for this resource retention function. We used simulated landscape maps where resource flows over map surfaces were directional and where landscape patch attributes were known. Although DLI was most strongly related to patch cover, it also logically related to patch number, size, shape, arrangement and orientation. If the direction of resource flow is multi-directional, a variant of DLI, the multi-directional leakiness index (MDLI) can be used. The utility of DLI and MDLI was demonstrated by applying these indices to three Australian savanna landscapes differing in their remotely sensed vegetation patch attributes. These leakiness indices clearly positioned these three landscapes along a function-dysfunction continuum, where dysfunctional landscapes are leaky (poorly retain resources). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Identification ofTomato Mottle Taino Begomovirus strains in Cuban potato fields     

Marlene Cordero  Pedro L. Ramos  Lester Hernández  Ana I. Fernández  Ana L. Echemendía  Rudy Peral  Gloria González  Daniel García  Surey Valdés  Ana Estévez  Keren Hernández 《Phytoparasitica》2003,31(5):478-489

The presence of a begomovirus in potato plants with yellow mottle symptoms was determined for the first time in Cuba. The incidence of typical begomovirus-like symptoms in potato plants in some regions of Havana province (Güira de Melena, San José de las Lajas, Güines and Boyeros) during the growing seasons from 1992 to 1998 was in general low. However, in some cultivars belonging to the National Program for Potato Genetic Improvement, the incidence reached 100%. Yield losses, determined in 1992 and 1994, ranged as high as 19% to 56.33% depending on the cultivar. Characterization of the causal agent was done by light microscopy, host range (graft and mechanical transmission), DNA hybridizations, polymerase chain reaction, and restriction fragment length polymorphism analysis. Nucleotide sequence of the amplified fragments revealed the presence ofTomato mottle Taino virus. The virus was transmittedvia tubers and has been detected in mixed infections withPotato virus X and withPotato leaf roll virus. http://www.phytoparasitica.org posting Oct. 20, 2003. The first two authors contributed equally to this work.  相似文献   

Evidence that a Leaf-Disk Test Allows Assessment of Isolate-Specific Resistance in Brassica oleracea Crops Against Downy Mildew (Peronospora parasitica)     

Bérénice Agnola  Stéphane Boury  Claudie Monot  Anne Quillévéré  Yves Hervé  Drissa Silué 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(5):471-478

A rapid resistance/susceptibility test for Peronospora parasitica (downy mildew) was established by inoculating leaf-disks of four Brassica oleracea accessions. Several conditions were tested: disk disinfection or not, agar medium with or without nutrients and with 50 or 100 ppm of benzimidazole. Using disinfected disks placed on agar (no nutrient and benzimidazole at 50 or 100 ppm), the responses of leaf-disks to four isolates were similar to those obtained using the classical cotyledon test, whereas undesired contaminations occurred in all other conditions. The possible effect of the particular leaf used for obtaining the disks was also studied. In each incompatible interaction tested, disks were resistant whatever the leaf used. In compatible interactions, susceptible phenotypes were observed on disks derived from the six lowest leaves, but disks from upper leaves were resistant. The genetic basis of resistance in a F1 hybrid broccoli was assessed, by testing six isolates on an F2 population derived from this hybrid. The cotyledon test only allows inoculation of two isolates per seedling, whereas many isolates can be tested on each plant by using leaf-disks. The segregation of the resistance to each of the six isolates was analysed: two dominant genes (tightly linked) control resistance to all isolates (one to five isolates; the other to only one isolate).  相似文献