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191.
Clostridium perfringens which is a causative agent of several diseases in animals and humans is capable of producing a variety of toxins. Isolates are typed into five types on the basis of the presence of one or more of the four major toxins genes, i.e. cpa, cpb, etx, and iap. A decade ago another toxin termed beta2 (beta2) and its gene (cpb2) were identified. Two alleles of cpb2 are known and a possible link between differences in gene expression and allelic variation has been reported. A correlation between the level of expression and the origin of the isolates has also been suggested. The demonstration and typing of the cpb2 gene in the genome of isolates can be seen as a vital part of research on the role of the beta2 toxin in the pathogenesis of disease. This study describes a PCR with a single primer set which in contrast to published primer sets recognizes both alleles. Subsequent restriction enzyme analysis of the PCR product enables typing of the alleles. Applying this protocol on a total of 102 isolates, a sub-variant was found which occurred only in C. perfringens isolates from pigs and appeared to be the predominant variant found in C. perfringens isolates from this species.  相似文献   
192.
Shortness of the lower jaw (brachygnathia inferior, underbite, overshot, parrot mouth) is an inborn and mostly hereditary malformation often seen in many sheep breeds. Chromosomal anomalies are generally not involved in brachygnathia inferior. Viral infections, teratogenic drugs and alkaloids of plants often lead to craniofacial malformations associated with brachygnathia inferior. A maternal deficiency of iron is discussed as a cause for brachygnathia inferior. We performed a three-year breeding trial using mainly East Friesian milk sheep affected by brachygnathic occlusion. Mating schemes included affected by affected and affected by unaffected matings. In the breeding trial, 60 lambs were born and from these 37 animals had variable degrees of brachygnathia inferior. The brachygnathic condition increased with rising age of the lambs. Extremely affected lambs showed palatine ulcers and growth retardation. Moreover, some animals had abnormal positions of the incisor teeth, distortion of the lower jaw and deformities of the external ear. Analysis of the pedigree did not support a monogenic inheritance pattern. An oligogenic inheritance including a dominant and recessive locus responsible for the major gene effects and possibly further modifying loci appeared much more likely. Other causes for brachygnathia inferior such as viral infections and anemia of the ewes could be ruled out. Chromosomal abnormalities were not evident and thus, large chromosomal defects were not associated with brachygnathia inferior.  相似文献   
193.
In this study the quality of digital and analog radiography in dogs was compared. For this purpose, three conventional radiographs (varying in exposure) and three digital radiographs (varying in MUSI-contrast [MUSI = MUlti Scale Image Contrast], the main post-processing parameter) of six different body regions of the dog were evaluated (thorax, abdomen, skull, femur, hip joints, elbow). The quality of the radiographs was evaluated by eight veterinary specialists familiar with radiographic images using a questionnaire based on details of each body region significant in obtaining a radiographic diagnosis. In the first part of the study the overall quality of the radiographs was evaluated. Within one region, 89.5% (43/48) chose a digital radiograph as the best image. Divided into analog and digital groups, the digital image with the highest MUSI-contrast was most often considered the best, while the analog image considered the best varied between the one with the medium and the one with the longest exposure time. In the second part of the study, each image was rated for the visibility of specific, diagnostically important details. After summarisation of the scores for each criterion, divided into analog and digital imaging, the digital images were rated considerably superior to conventional images. The results of image comparison revealed that digital radiographs showed better image detail than radiographs taken with the analog technique in all six areas of the body.  相似文献   
194.
A case of canine cutaneous sterile pyogranuloma/granuloma syndrome (SPGS) with generalized asymmetrical alopecia and plaques is described. Results from histopathologic examination were suggestive of SPGS and failed to demonstrate any etiological agent. A systematic approach on how to definitively rule out infectious skin diseases is discussed.  相似文献   
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BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP.  相似文献   
199.
In September 2004, a neonatal sea otter pup was found alive on the beach in northern Monterey Bay, CA. Efforts to locate the mother were unsuccessful. Due to a poor prognosis for successful rehabilitation, the pup was euthanized. Postmortem examination revealed emaciation, systemic lymphadenopathy and a malformation of the left cerebral temporal lobe. On histopathology, free tachyzoites and tissue cysts compatible with Toxoplasma gondii were observed in the brain, heart, thymus, liver, lymph nodes and peri-umbilical adipose. The presence of T. gondii within host tissues was associated with lymphoplasmacytic inflammation and tissue necrosis. Immunofluorescent antibody tests using postmortem serum were positive for anti-T. gondii IgM and IgG (at 1:320 and 1:1280 serum dilution, respectively), but were negative for IgG directed against Sarcocystis neurona and Neospora caninum (<1:40 each). Brain immunohistochemistry revealed positive staining for tachyzoites and tissue cysts using antiserum raised to T. gondii, but not S. neurona or N. caninum. T. gondii parasite DNA was obtained from extracts of brain and muscle by PCR amplification using the diagnostic B1 locus. Restriction enzyme digestion followed by gel electrophoresis and DNA sequencing confirmed the presence of Type X T. gondii, the strain identified in the majority of southern sea otter infections.  相似文献   
200.
Focus of this study was to evaluate the most suitable breed/crossbred and the appropriate nutritional strategies to increase marbling in beef muscle and to improve its healthy properties, in particular the n‐3 fatty acids content. One hundred and seventy‐six heifers of three crossbreed commonly reared by Emilia‐Romagna farmers: 48 Bleu Belge × Freisian (ITA), 48 Charolais × Aubrac (FRA), and 80 Angus (ANG) were used. Animals of each breed were randomly subdivided in two experimental groups that received two diets, differing for the dietary lipid source. Control group (C) received a basal diet containing protected vegetable fats, whereas treated one (T) received the same basal diet supplemented with 0.9 kg/head/day of extruded flaxseed. After slaughtering, a sample of Longissimus thoracis was collected from each animal for meat quality analysis. Our results demonstrated that, in a shorter fattening period, ANG animals obtained the best dry matter intake, average daily gain and the best fattening scores. ITA and ANG meat presented the highest marbling scores. ANG breed had the highest amount of C18:1, the highest unsaturated/saturated fatty acids ratio and the lowest n‐6/n‐3 ratio. The T animals, independently from breed, showed the highest amount of α‐linolenic acid (ALA). In addition, ANG‐T meat presented the highest ALA content.  相似文献   
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