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81.
Serology is currently used for the diagnosis of canine sino-nasal aspergillosis (SNA). However, the accuracy of serological testing using commercially available, standardized purified antigen preparations of Aspergillus (CAPurAspAg) has only been poorly documented. The aim of the present study was to assess the diagnostic value of an agar-gel double immunodiffusion (AGDD) test and an anti-Aspergillus IgG ELISA, using CAPurAspAg and the commercially available Platelia test for the detection of serum galactomannan. Sera from 17 dogs with SNA, 18 dogs with a nasal tumour (NT), 11 dogs with lymphoplasmacytic rhinitis (LPR) and 33 control dogs were tested with the 3 methods. AGDD result was positive in 76.5% of dogs with SNA, whereas all sera from dogs with non-fungal nasal disease and control dogs were negative. A positive IgG ELISA result was obtained in 88% of dogs with SNA and in 18% of dogs with LPR. All patients with NT and control dogs had a negative IgG ELISA result. The Platelia test was positive in 24% of dogs with SNA, 11% of dogs with NT, 9% of dogs with LPR and 24% of control dogs. The results of this study suggest that (1) the detection of serum Aspergillus-specific antibodies with AGDD or ELISA, using CAPurAspAg, provides excellent specificity and good sensitivity, (2) the specificity is higher for AGDD (100%) than for ELISA (96.8%) while sensitivity is higher for ELISA (88.2%) than for AGDD (76.5%) and (3) serum galactomannan quantification with the Plateliat test is unreliable for the diagnosis of canine SNA.  相似文献   
82.
The sizes of workers from raiding columns and an excavated colony of Megaponera foetens, were determined using measurements of interocular distance and scape length. These measurements confirmed that workers exhibit monophasic allometry. Analysis of the frequency distribution of worker sizes in samples taken from columns and the nest, did not reveal any significant differences, indicating that workers of all sizes are recruited for foraging. However, the two largest size classes of workers predominate in the samples from the nest, suggesting that these individuals may be Involved in reproduction.  相似文献   
83.
Reasons for performing study: In horses, serum cortisol concentration is considered to provide an indirect measurement of stress. However, it includes both free and bound fractions. The sampling method is also invasive and often stressful. This is not the case for salivary cortisol, which is collected using a more welfare‐friendly method and represents a part of the free cortisol fraction, which is the biologically active form. Objectives: To compare salivary and serum cortisol assays in horses, in a wide range of concentrations, using an adrenocorticotropic hormone (ACTH) stimulation test, in order to validate salivary cortisol for stress assessment in horse. Methods: In 5 horses, blood samples were drawn using an i.v. catheter. Saliva samples were taken using swabs. Cortisol was assayed by radioimmunoassay. All data were treated with a regression method, which pools and analyses data from multiple subjects for linear analysis. Results: Mean ± s.d. cortisol concentrations measured at rest were 188.81 ± 51.46 nmol/l in serum and 1.19 ± 0.54 nmol/l in saliva. They started increasing immediately after ACTH injection and peaks were reached after 96 ± 16.7 min in serum (356.98 ± 55.29 nmol/l) and after 124 ± 8.9 min in saliva (21.79 ± 7.74 nmol/l, P<0.05). Discharge percentages were also different (225% in serum and 2150% in saliva, P<0.05). Correlation between serum and salivary cortisol concentrations showed an adjusted r2= 0.80 (P<0.001). The strong link between serum and salivary cortisol concentrations was also estimated by a regression analysis. Conclusions: The reliability of both RIAs and regression found between serum and salivary cortisol concentrations permits the validation of saliva‐sampling as a noninvasive technique for cortisol level assessment in horses.  相似文献   
84.
The circulation of the deep Atlantic Ocean during the height of the last ice age appears to have been quite different from today. We review observations implying that Atlantic meridional overturning circulation during the Last Glacial Maximum was neither extremely sluggish nor an enhanced version of present-day circulation. The distribution of the decay products of uranium in sediments is consistent with a residence time for deep waters in the Atlantic only slightly greater than today. However, evidence from multiple water-mass tracers supports a different distribution of deep-water properties, including density, which is dynamically linked to circulation.  相似文献   
85.
Summary Twenty carnation genotypes of diverse origin were planted in September and were kept under an 8h day and a light intensity of 15 W/m2 visible radiation in a phytotron from 30 November to 24 February. Long photoperiods (24 h; LD) were applied in December-January for 25 days. In addition to flowering dates of individual shoots, records wer kept on shoot development (number of visible leaf pairs) on four dates: (1) six weeks after pinching, (2) at the beginning of the LD treatment in December, (3) when plants were transferred from the phytotron to the glasshouse in February and (4) at the time of flowering of individual shoots.The genetic variation in number of visible leaf pairs on each of these dates, in relation to shoot position and rate of unfolding of leaf pairs, was analysed.On the basis of these analyses, the between and within-genotype variation in time of flowering, yield distribution and LD response could be, at least partly, related to variation in the above-mentioned parameters. It was established that relevant genetic variation exists in (1) the initial development of the axillary bud from which a primary shoot is produced after pinching; (2) the rate of leaf unfolding; (3) the minimum number of leaf pairs required for flower initiation and (4) the within-plant variation in the above three characters in relation to shoot position.  相似文献   
86.
87.
The objective was to compare alternative models for fitting to data on degradation of dry matter (DM), organic matter (OM) and crude protein (CP) in the rumen of two harvests of four temperate grasses, made into hay in Belgium, and one harvest of three tropical grasses commonly used in Burundi. Fifteen non-linear models were used and these included generalized Mitscherlich, simple Mitscherlich (or exponential), generalized Michaelis–Menten, Gompertz, logistic, simple Michaelis–Menten, segmented Van Milgen and von Bertalanffy models. Degradation profiles of DM, OM and CP obtained in sacco from the rumen of three mature sheep were fitted to all the models. The convergence success rate along with acceptable parameters was used as a first tool to eliminate models. Comparisons between the remaining twelve models were then made using the run test of sign, the root mean square prediction error, the root mean square error, the lack of fit test and the variance ratio test criteria. On the basis of an overall assessment using these tests, the Gompertz lagged model was the best suited to fit the degradation data of both temperate and tropical grasses. This study confirmed the superiority of sigmoid type functions over diminishing return-type models.  相似文献   
88.
89.
For 15 months the anticoccidial effect of 200 ppm clopidol/methyl benzoquate and of 50 ppm robenidine, and the development of immunity against five different species of Eimeria were followed in a closed rabbit population. In unmedicated rabbits, oocyst output decreased progressively with increasing age to a very low level in animals older than four months, but none of the species present disappeared completely in adult animals. No clinical symptoms nor mortality from coccidiosis was noted in reproduction stock. In field conditions E magna and E perforans seemed to induce the weakest resistance, whereas a more marked resistance has been found for E intestinalis and E irresidua. E media appeared to have an intermediate position. Robenidine reduced oocyst output of E magna, E intestinalis, E irresidua, E media and E perforans significantly, whereas clopidol/methyl benzoquate reduced oocyst output of the latter four species only and was least active against E magna. Both drugs also reduced coccidiosis-induced mortality significantly. Medication only before weaning had no distinct influence on coccidial infection, or on mortality by coccidiosis after weaning; nor did those parameters differ significantly between continuously medicated rabbits and rabbits medicated after weaning only. As reproductive stock is protected by immunity, this makes the necessity of medicating does and bucks with anticoccidials questionable in intensive or semi-intensive reproduction systems.  相似文献   
90.
Twenty-four Bouviers with dysphagia were examined between October 1986 and October 1988. The type of dysphagia was characterised by the results from the clinical examination, the videofluorographic examination and the electromyographic recordings from the oral, pharyngeal, and esophageal muscles. Electromyography indicated neurogenic as well as myogenic causes of dysphagia. Tissues from 10 dogs were available for histopathologic examination. In nine dogs there was a progressive muscular degeneration of the pharyngeal and/or esophageal muscles, resembling muscular dystrophy. In two of these dogs the same abnormalities were also noticed in the masseter and temporalis muscles and in the intrinsic laryngeal muscles. In one dog small areas with hyalin degeneration and fragmentation of muscle fibres were found in the cricopharyngeal muscle. No abnormalities in nerve tissue were found. Muscular dystrophy is a hereditary disease. The mode of transmission in these Bouviers is not yet known.  相似文献   
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