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941.
M Hertel U Kersten R Mischke I Nolte 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(6-7):239-242
Based on results of holter ecg recordings taken from 38 dogs the computerized analyses system turned out as method not exactly valuing the frequency and sensitivity of arrhythmias. Despite there was a significant correlation between the computerized and visual arrhythmia analysis for ventricular respectively supraventricular premature beats, in individual cases there was an important aberration between the particular values. 相似文献
942.
1. Growth of the oesophagus, proventriculus, gizzard, intestine, liver and pancreas weight was investigated in Mallards, White Pekins, Muscovies and a Muscovy x White Pekin cross. The birds varied in age between hatching and 154 d. The data were analysed by fitting both the Janoschek growth curve and the allometric formula. 2. The growth rate of all organs, except the oesophagus, peaked earlier (30 d for Muscovies and 14 d for the other breeds) than body weight and they grew faster to any given percentage of their final weight. In contrast, oesophagus weight showed growth curve characteristics similar to body weight. 3. Oesophagus weight showed simple, slightly negative allometry. The remaining organs followed complex allometry that can approximately be described by 2 allometric stages. The 1st phase was isometric to positive allometric. The 2nd showed marked negative allometry. 4. These growth patterns are assumed to be generally present in birds. 相似文献
943.
Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis. 相似文献
944.
The use of chance-corrected agreement to diagnose canine compulsive disorder: an approach to behavioral diagnosis in the absence of a 'gold standard'.
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This study assessed the diagnostic accuracy of formal diagnostic criteria for canine compulsive disorder (canine CD). Canine CD is a syndrome of abnormal behaviors that are believed to result from conflict or frustration. Differential diagnoses include normal conflict behavior and learned behavior. In studies of canine CD, confidence in the diagnosis comes with knowing the accuracy of the diagnostic method. This accuracy may be quantified as the chance-corrected agreement between the diagnostic method and a 'gold standard' diagnostic test. The present study examined the agreement between diagnoses of canine CD made by an expert (the 'gold standard') and by using formal diagnostic criteria. The owners of 84 dogs suspected of having CD received 2 telephone interviews. The first utilized a detailed, pre-tested questionnaire; a dog was then diagnosed with CD if the behavioral history met 7 diagnostic criteria. The second interview was given by a behavioral expert whose diagnosis was based on personal experience. The interviewers were blind to each other's diagnoses. The chance-corrected agreement between diagnoses was minimal (kappa = 0.02) and disagreement was associated with 3 of the formal criteria: a history of conflict or frustration, an increase in the number of contexts that elicit the behavior, and an increase in the daily frequency of the behavior. Reasons for the disagreement include the order of the interviews, response biases, the setting of the interviews, and, possibly, the diversity of the behaviors associated with canine CD. To the authors' knowledge, this type of study is the first in clinical ethology to address validation of the diagnostic method. The results indicate 3 developmental aspects of canine CD that should be examined in future work. 相似文献
945.
R Eicher L Audigé U Braun J Blum M Meylan A Steiner 《Schweizer Archiv für Tierheilkunde》1999,141(9):423-429
The aims of the study were to determine the prevalence of cecal dilatation/dislocation (CDD) and abomasal displacement (DA) in Switzerland, to identify risk factors for both diseases, and to compare directly their epidemiologic situation. The epidemiologic study included 158 cases of CDD and 149 cases of DA from the cases referred to both University Clinics of Berne and Zurich. The results showed that DA was associated with nutrition-related risk factors: use of minerals and sodium chloride, inadequate concentrate feeding and beginning of the feeding. Furthermore, breed was significantly associated with DA, but not with CDD. Finally, milk yield and pasture were also significantly included in the models. For CDD, nutrition-related risk factors were also found: pasture in summer, use of corn pellets and corn silage in winter. In the final model, protein concentrate was also included. Although both diseases were found at comparable frequencies, the results of this study indicate marked differences between the epidemiology of occurrence of CDD and DA. Therefore, the hypothesis of a common etiopathogenesis appears unlikely. 相似文献
946.
Feline calicivirus (FCV) was isolated from one of four dead fetuses delivered by ovariohysterectomy from a queen with an acute FCV infection. The most prominent lesions in the fetuses were petechial haemorrhages in the skin. The virus isolated was characterised as FCV by antigenic analysis and cDNA sequence analysis. This is the second report of abortion associated with acute FCV infection. 相似文献
947.
Diseases caused by Moniliophthora roreri (moniliasis), Crinipellis perniciosa (witches’ broom) and Phytophthora palmivora (black pod) are the most important factors limiting cocoa production in Peru and cultural management is considered to be the only practical means of control for the smallholder. The objective of this study was to develop an epidemiologically and economically sound control recommendation based on the frequency of phytosanitary pod removal. Weekly removal of diseased pods reduced the incidence of diseases significantly in comparison with fortnightly removal. In three fields, moniliasis was decreased by 26–41%, black pod by 35–66% and witches’ broom on pods by 14–57%. The cumulative effect was a consistent yield increase from an average of 504–660 kg ha−1 yr−1. Returns compensated for increased labour costs. Weekly pod removal was 32% more profitable. Time-course analyses indicated that weekly removal should be practised throughout the year under field conditions of eastern Peru. 相似文献
948.
U. H. Schulz 《Fisheries Management and Ecology》1999,6(3):187-194
Abstract The local migratory behaviour of lake trout, Salmo trutta L., and resident brown trout, S. trutta L., progeny from an inflowing stream of Lake Constance was compared. No differences were detected with respect to emigration rate (3.5% and 4.2% for lake trout and resident trout, respectively), rate of residency (6.8% and 8.2% for lake trout and resident trout, respectively) and rate of survival (12.3% and 12.1% for lake trout and resident trout, respectively) one year after stocking. Some of the resident brown trout offspring became migrants and vice versa . The results indicate that the progeny of riverine brown trout contribute considerable numbers to lake trout stock. 相似文献
949.
C. Stockhaus B. Kohn R. Rudolph L. Brunnberg U. Giger † 《The Journal of small animal practice》1999,40(7):326-331
Sixty female dogs with untreated mammary carcinoma, comprising equal numbers of dogs in tumour stages I to IV, were evaluated for haemostatic abnormalities using the following tests: platelet count, prothrombin time, activated partial thromboplastin time, thrombin time, plasma activity of factor V, VIII and X, plasma concentration of fibrinogen, fibrin monomers and fibrinogen degradation products, and plasma antithrombin III activity. Two-thirds of all dogs had one or more haemostatic test abnormality of which the likelihood and frequency was increased in those with stage III and IV neoplasia. Haemostatic abnormalities were more frequently observed in dogs which had mammary tumours with distant metastases, extended tumour necrosis, inflammatory carcinomas, tumours fixed to underlying structures, or tumours in which there was penetration of the tumour capsule by tumour cells. As in humans with mammary carcinoma, these haemostatic abnormalities might be used as prognostic indicators, but their clinical importance remains unknown. 相似文献
950.
Appraisal and standardization of curvilinear velocity (VCL) cut‐off values for CASA analysis of Japanese quail (Coturnix japonica) sperm
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One of the basic steps in objective analysis of sperm motility is the subdivision of a motile sperm population into slow, medium and rapid categories based on their velocity. However, for CASA analysis of quail sperm, the velocity values for categorization of slow, medium and rapid sperm have not yet been standardized. To identify the cut‐off values of “velocity curvilinear” (VCL) for quail sperm categorization, we captured and analysed 22,300 tracks of quail sperm using SCA®‐CASA. The median and mean VCL values were 85 and 97 μm/s. To define the VCL cut‐off values, we used two methods. In the first, we identified the upper (rapid sperm) and lower (slow sperm) cut‐off values using: (i) median VCL ± 25% or ± 50% or ± 75% of median VCL value; (ii) first and third quartile values of VCL data (i.e. 25% cut‐off setting); and (iii) 33% and 66% of VCL data. Among these settings, sperm categories and their corresponding motility characteristics recorded using the “25%” setting (i.e. slow ≤36 ≤ medium ≤154 ≤ rapid) were found the most realistic and coherent with male ranking by fertility. In the second method, we calculated heteroscedasticity in the total VCL data using PCA and the two‐step clustering method. With this approach, the mean of the high and low clusters was 165 and 51 μm/s, respectively. Together, the mean from two methods suggested that, for SCA®‐CASA categorization of quail sperm, sperm should be classed as “rapid” at VCL ≥160 μm/s and “slow” at VCL ≤45 μm/s. 相似文献