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Thirty adult dogs with naturally acquired gastrointestinal nematode infections were assigned at random to ten replicates and treated daily for 3 days with either a combination febantel/praziquantel (Vercom) paste, febantel tablets or placebo tablets. Numbers of hookworm and whipworm eggs after treatment were reduced similarly for both drug formulations when compared with pretreatment egg counts, whereas these counts increased in the controls. Vercom paste reduced the hookworm egg count by 99.9% and the whipworm egg count by 99.6%. The febantel tablet decreased the hookworm egg count by 99.9% and the whipworm egg count by 100%. As determined at necropsy, the controlled test efficacy against adult hookworms and whipworms was similar for the Vercom paste and the febantel tablets. The controlled test efficacies of Vercom paste against Ancylostoma caninum, Ancylostoma braziliense, and Trichuris vulpis were, respectively, 99.7%, 100% and 95.8% and those of febantel tablets were 98.2%, 100% and 99.7%. These results indicate that the nematocidal efficacy of febantel against these nematodes remains unchanged in these two formulations. No adverse reactions to either febantel tablets or to Vercom paste were observed.  相似文献   
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The predominant immunoglobulin isotype on most mucosal surfaces is secretory immunoglobulin A (SIgA), a polypeptide complex comprising two IgA monomers, the connecting J chain, and the secretory component. The molecular stability and strong anti-inflammatory properties make SIgA particularly well suited to provide protective immunity to the vulnerable mucosal surfaces by preventing invasion of inhaled and ingested pathogens. In contrast to SIgA, IgA in serum functions as an inflammatory antibody through interaction with FcalphaR on immune effector cells. Although IgA appears to share common features and protective functions in different species, significant variations exist within the IgA systems of different species. This review will give an overview of the basic concepts underlying mucosal IgA defence which will focus on the variations present among species in structure, antibody repertoire development, pIgR-mediated transport, colostral IgA content, hepatobiliary transport, and function with particular emphasis on the IgA system of the pig and dog. These interspecies variations emphasise the importance of elucidating and analysing the IgA system within the immune system of the species of interest rather than inferring roles from conclusions made in human and mouse studies.  相似文献   
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Minimal nitrogen requirements of Corynebacterium renal strains   总被引:2,自引:0,他引:2  
Corynebacterium renale strain 10849 was grown in a chemically defined medium containing glucosamine, ammonium sulfate, and 5 amino acids as possible nitrogen sources. Although glucosamine was slightly stimulatory, its omission from the medium had a minimal effect on growth, and washed cells introduced into glucosamine-free medium grew readily through 10 serial transfers, demonstrating that this compound was not required for growth. Individual omissions of isoleucine, valine, methionine, and glutamine resulted in lengthened lag periods and reduced growth rates in initial transfers, but recovery occurred in subsequent serial transfers so that by the 3rd or 4th transfer, growth rates and cell crops were only slightly less than in control cultures in complete medium. Omission of cystine resulted in a permanently low growth rate and reduced cell crop, but this was remedied by substituting various nonnitrogenous compounds containing reduced sulfur. Strain 10849 and 6 additional strains were then serially cultured in a minimal defined medium in which sodium thioglycolate provided reduced sulfur and ammonium sulfate served as sole nitrogen source. Since only ammonium ion was required as the nitrogen source, it could be concluded that C renale, which rapidly hydrolyzes urea, should find an adequate source of nitrogen for growth in the urinary tract of animals.  相似文献   
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There is global recognition that sustainable land use requires monitoring that will detect change on a scale that protects the resource. That fundamental necessity is threatened where labor-intensive methods and high labor costs cause sampling deficiencies and increased Type-II error rates (false negatives). Ground-based imaging is a monitoring method that reduces monitoring labor costs. Nadir (vertical) images acquired with common digital cameras can be manually analyzed for cover using free software. We used an innovative field protocol to acquire standardized, freehand, nadir images (samples) of rangeland, then compared point intercept (PI) and image-analysis techniques. Between methods, precision (repeatability) across users was equivalent; cover measurements were often different, and the image-analysis technique took only a third as long to complete. Image analysis has several advantages over PI besides the reduced labor cost: Images are permanent resource records available for reanalysis if data are questioned, if software improves, or if management objectives change; and image analysis is less biased by moving vegetation, moving pointing devices, and bright vegetation color.  相似文献   
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1. Thirty adult female pigeons (Columba livia domestica) were randomly divided into 3 equal groups; the 1st and 2nd groups were immunised with bovine serum albumin (BSA) at 0 and 20 d, the 2nd group also received 1 g L-carnitine per litre of drinking water from -5 to 25 d post-immunisation (dpi) and the 3rd group, a control group, received neither treatment. 2. Body weights and serum samples were taken at 0, 5, 10, 15, 20, 25, 30 and 35 dpi. 3. Both BSA-specific IgG and IgM responses were enhanced by about 10% by L-carnitine supplementation. 4. L-carnitine supplemented pigeons showed a higher water consumption. Body weight loss during the onset of the immune response showed a slight tendency to be counteracted by L-carnitine supplementation. 5. The impact of L-carnitine on resistance and resilience to an immunological challenge is discussed.  相似文献   
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The control of foot-and-mouth disease virus (FMDV) outbreaks in non-endemic countries relies on the rapid detection and removal of infected animals. In this paper we use the observed relationship between the onset of clinical signs and direct contact transmission of FMDV to identify predictors for the onset of clinical signs and identify possible approaches to preclinical screening in the field. Threshold levels for various virological and immunological variables were determined using Receiver Operating Characteristic (ROC) curve analysis and then tested using generalized linear mixed models to determine their ability to predict the onset of clinical signs. In addition, concordance statistics between qualitative real time PCR test results and virus isolation results were evaluated. For the majority of animals (71%), the onset of clinical signs occurred 3–4 days post infection. The onset of clinical signs was associated with high levels of virus in the blood, oropharyngeal fluid and nasal fluid. Virus is first detectable in the oropharyngeal fluid, but detection of virus in the blood and nasal fluid may also be good candidates for preclinical indicators. Detection of virus in the air was also significantly associated with transmission. This study is the first to identify statistically significant indicators of infectiousness for FMDV at defined time periods during disease progression in a natural host species. Identifying factors associated with infectiousness will advance our understanding of transmission mechanisms and refine intra-herd and inter-herd disease transmission models.  相似文献   
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