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161.
A 14-year-old female bottlenose dolphin was diagnosed with mycobacterial panniculitis based on punch biopsy specimens. The necropsy revealed numerous pyogranulomas in the blubber, as well as marked acute multifocal necrosuppurative pneumonia and lymphadenitis. In addition, the animal had marked scoliosis, which had first been noted clinically in the dolphin at about 1 mo of age. The animal had been treated with low-dose dexamethasone for approximately the last 19 mo to reduce perceived discomfort from spondyloarthritis and with the progestational agent altrogenest for approximately 8 yr to prevent pregnancy. Acid-fast positive bacilli were detected in the dermis but not in lung or lymph nodes. Mycobacterium chelonae was isolated from pooled skin, lung, and peripheral lymph-node tissue. Mycobacterial infection may be considered as a differential diagnosis in bottlenose dolphins with generalized cutaneous inflammation, particularly if chronic steroid and progesterone treatments were administered, both of which may have an immunomodulatory effect.  相似文献   
162.
Genetic resistance to the gastro-intestinal parasites of lambs can contribute to sustainable systems of parasite control with associated benefits for health and welfare. This study reports estimates of the genetic parameters of strongyle egg counts (FEC), Nematodirus egg counts (NEM), faecal consistency scores (FCS) and their associations with growth and ultrasonic measurements of muscle (UMD) and fat (UFD) depths in lambs. The lambs were the progeny of 45 Bluefaced Leicester sires from Scottish Blackface and Hardy Speckled Face dams. Faecal samples were taken from lambs at 10, 14, 18, 22 and 26 weeks of age, giving 1024 to 3055 records per trait. Live weight was recorded for all lambs at 16 weeks and live weight, UMD and UFD were recorded in female lambs at 28 weeks. Mean FEC and NEM were significantly higher for twin versus single reared lambs, for male castrate versus female lambs and for the offspring of Scottish Blackface versus Hardy Speckled Face ewes. Heritability estimates for FEC were low (0.04 ± 0.02 to 0.20 ± 0.08) and showed a non-significant trend to increase with age. The phenotypic correlations between measures of FEC at different ages were low (0.06 to 0.34) but genetic correlations were not significantly different from one in most cases. Heritability estimates of NEM ranged from 0.05 ± 0.03 to 0.09 ± 0.05 and genetic correlations among counts at different ages were not significantly different from zero. FEC and NEM were strongly correlated genetically (0.62 to 0.93) and estimates of the genetic correlations between FEC and NEM with live weights (− 0.36 to 0.23), UMD (− 0.35 to 0.25) and UFD (0.08 to 0.55) were variable in sign, though not significantly different from zero. Heritability estimates for faecal consistency scores (FCS) were 0.06 ±0.03 to 0.11 ± 0.04, with strong genetic correlations between successive measures. FCS was not significantly correlated with FEC or lamb performance traits. It is concluded that selection for reduced strongyle egg counts in lambs at around 5–6 months of age will give favourable correlated responses in NEM in lambs, with limited correlated response in lamb performance or faecal consistency scores.  相似文献   
163.
    
The mechanisms of embryo‐maternal communication during the first days of embryonic life are largely unknown. Using the bovine as a model, the aims of our study were to morphologically characterize the interaction between the pre‐implantation embryo and the epithelium of the maternal ampulla, isthmus and uterotubal junction by light and scanning electron microscopy. For this purpose, oviducts were removed from cows revealing a functional corpus luteum on day 3 after insemination. These were compared to oviducts removed on day 3 (metestrus) of the estrous cycle. Three days after insemination, the majority of the epithelial cells in the ampulla were secretory cells distinctly protruding into the oviductal lumen. Contrary the ampulla of cows on day 3 of the cycle predominantly revealed ciliated cells in the oviductal epithelium. As shown by Periodic Acid Schiff reaction (PAS) with and without amylase digestion, the secretory cells of the ampulla synthesized merely glycoproteins during metestrus, but large amounts of glycogen during pregnancy. In the isthmus no morphological differences were seen between pregnant and cyclic cows. The most conspicuous finding during pregnancy was seen in the uterotubal junction: Vital cumulus cells embedded in between epithelial cells had developed short cytoplasmic processes intensely contacting the epithelial uterine cells. The embryos obtained ex vivo were regularly covered with a thick layer of homogenous extracellular matrix. Contrary embryos produced in vitro– both with and without coculture with oviductal cells –revealed a clearly visible zona pellucida with spongy appearance and numerous pores. Our results imply that already during the first days of life there is intense interaction of the pre‐implantation embryo and the maternal genital tract part of which may be mediated by cumulus cells.  相似文献   
164.
    
We have recently provided evidence that Texas feline immunodeficiency virus (FIV-TX) isolates are an emerging subtype sharing a common ancestry with clade B isolates. Specific, pathogen-free cats were infected, intravenously, with 500, 2000 or 8000TCID(50) of the FIV-TX53 virus to study the acute stage of infection. Infection of cats resulted in lymphadenopathy at 10 days post-infection (p.i.). By 7 weeks p.i., gag specific antibody could be detected from sera of all infected cats. Virus could be detected by culturing PBMC and by nested capsid PCR. A reduction in the absolute numbers of lymphocytes and neutrophils was observed in infected cats although there was no trend identified between this reduction and the viral dose administered. By 11 weeks p.i., the CD4(+)/CD8(+) T cell ratios from all infected cats had dropped from approximately 2 to below 1. While decrease in the ratio was dependent on the viral dose, the T cell ratios of cats receiving the highest dose had significantly dropped below 1 by 4-7 weeks p.i. This decrease in the ratio was accompanied by a sharp and temporal decline in the absolute CD4(+) T cells and a slight increase in the absolute CD8(+) T cell numbers with a dramatic expansion of cells with CD8beta(low) chain expression.  相似文献   
165.

Introduction

Left ventricular systolic function is one of the main parameters studied in echocardiography. Longitudinal systolic function, however, is less commonly evaluated in routine examinations but may provide early information on systolic dysfunction. The movement of the mitral annulus toward the apex has already been determined as a method for evaluation of longitudinal systolic function in dogs, but the study of this movement by speckle tracking with the tissue motion annular displacement (TMAD) technique has not yet been evaluated.

Animals

One hundred fifty-three client-owned healthy dogs.

Methods

Cross-sectional study. One hundred fifty-three client-owned healthy dogs underwent physical examination, electrocardiography, blood pressure measurement, and a standard and speckle tracking echocardiography. Systolic function was evaluated by global longitudinal strain (GLS) and TMAD. These parameters were compared with the standard echocardiographic data.

Results

A correlation was found between GLS, TMAD, and body weight. Tissue motion annular displacement and GLS were significantly correlated (p < 0.001) with other surrogates of systolic function, including ejection fraction and fractional shortening. There were no differences in TMAD between sexes. The coefficient of variation (CV) of the intraobserver evaluation in the global TMAD (CV 4.44) was slightly higher than that in the GLS (CV 3.74). Also, TMAD was not influenced by heart rhythm and could be acquired more rapidly than GLS.

Conclusions

Tissue motion annular displacement is a rapid and reproducible method for the assessment of left ventricle longitudinal function in healthy dogs. However, more studies are needed to validate the real clinical applicability of TMAD in animals with heart diseases.  相似文献   
166.
Serous retinal detachment, associated with optic disk pit, was diagnosed in 28 eyes of 24 dogs. Xenon arc photocoagulation was used in treatment of the detachment. Of 24 dogs, 21 were Collies. In 23 eyes, retinal detachments affected temporal and/or inferior portions of the retina. In 5 eyes, detachments were predominantly superior and/or nasal. A single photocoagulation treatment resulted in reattachments in 25 eyes. Of the 3 remaining detachments, 2 eyes improved with additional photocoagulation, and 1 eye, which was not treated further, had a complete retinal detachment.  相似文献   
167.
A bio‐economic model including a computer program was developed where a large number of parameters can be modified to describe a great variety of production systems. Economic values for up to 27 traits can be calculated. Seasonal feeding is considered and protein requirement in addition to net energy may be taken into account when calculating feed requirement. Furthermore, the model allows for the evaluation of individual parts of the growth curve. The model was applied to the Czech Suffolk breed used in pure‐breeding. An extensive pasture system with spring lambing and sale of surplus progeny for slaughter after weaning or after a finishing period was assumed. The economic values (in Euro cent per ewe, per year and per genetic standard deviation of the trait) were as follows: 9.9 for birth weight, ?72.6 for mature weight, 142, 32.1 and 16.9 for growth rates till weaning, in rearing of breeding animals and in fattening, respectively, 19.9 and 101 for conception rate of female lambs and ewes, respectively, 690 for litter size per ewe lambing, 172 for productive lifetime of ewes, 402 and 503 for survival rate of lambs at lambing and till weaning, respectively, and 16.5 for fleece weight.  相似文献   
168.
  总被引:1,自引:0,他引:1  
Seven cats with osseous lesions as the primary manifestation of disseminated Histoplasma capsulatum infection were evaluated. The major clinical signs in these cats were related to the bony lesions and included lameness, bone pain, and soft tissue swelling of limbs and joints. Other clinical and pathologic findings were similar to previously reported forms of disseminated histoplasmosis in the cat. The radiographic appearance of the lesions was predominantly osteolytic; periosteal and endosteal new bone production was present in some cases. Infection occurred primarily in bones of the appendicular skeleton with a predilection for sites below the elbow and stifle joints.  相似文献   
169.
ABSTRACT Tan spot of wheat, caused by Pyrenophora tritici-repentis, provided a model system for testing disease forecasts based on an artificial neural network. Infection periods for P. tritici-repentis on susceptible wheat cultivars were identified from a bioassay system that correlated tan spot incidence with crop growth stage and 24-h summaries of environmental data, including temperature, relative humidity, wind speed, wind direction, solar radiation, precipitation, and flat-plate resistance-type wetness sensors. The resulting data set consisted of 97 discrete periods, of which 32 were reserved for validation analysis. Neural networks with zero to nine processing elements were evaluated 20 times each to identify the model that most accurately predicted an infection event. The 200 models averaged 74 to 77% accuracy, depending on the number of processing elements and random initialization of coefficients. The most accurate model had five processing elements and correctly predicted 87% of the infection periods in the validation set. In comparison, stepwise logistic regression correctly predicted 69% of the validation cases, and multivariate discriminant analysis distinguished 50% of the validation cases. When wetness-sensor inputs were withheld from the models, both the neural network and logistic regression models declined 6% in prediction accuracy. Thus, neural networks were more accurate than statistical procedures, both with and without wetness-sensor inputs. These results demonstrate the applicability of neural networks to plant disease forecasting.  相似文献   
170.
Pectolytic bacteria, including Pectobacterium spp. and Dickeya spp., are best isolated on crystal violet pectate (CVP), a semiselective medium containing pectin. The source of pectin is essential, because pectolytic bacteria are not able to degrade all of them. The aims of this study were to identify a new pectin source and to perfect formulations of semiselective CVP media to isolate the pectolytic bacteria Pectobacterium spp. and Dickeya spp. from different environmental compartments (plants, soil and water). The AG366 pectin, selected after screening six different formulations, was incorporated into single‐layer (SL‐CVPAG366) and double‐layer (DL‐CVPAG366) CVP media. Both media were compared with those based on Bulmer, Sigma‐Aldrich and Slendid‐Burger pectins, using 39 Pectobacterium and Dickeya strains. All strains formed deep cavities on AG366‐CVPs, whereas nine did not produce cavities on Bulmer or Sigma‐Aldrich media. Recovery rates were similar on DL‐CVPAG366, Sigma‐Aldrich and Bulmer CVPs for a given taxon, and did not differ significantly between SL‐ and DL‐CVPAG366. Pectolytic bacteria were successfully isolated on both media from field samples of diseased potatoes, carrots, tobacco, onions, radishes and ornamentals. AG366 is thus a high‐performance pectin source for the elaboration of CVP media suitable to isolate Dickeya and Pectobacterium. It is also efficient for enrichment purposes in liquid medium. The validation of AG366 as an improved source of pectin to recover the polyphagous Pectobacterium and Dickeya in different environmental compartments is essential given the current worldwide emergence and recrudescence of these bacteria.  相似文献   
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