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51.
CASE HISTORY A 15-year-old, brown-and-white cat was presented to a veterinary clinic with an ulcerated, reddened 1-cm diameter lesion on the nasal planum.

CLINICAL FINDINGS AND DIAGNOSIS: Histology of a biopsy sample confirmed the lesion was a squamous cell carcinoma (SCC). PCR amplified DNA sequences from two different papillomaviruses. One sequence was from FdPV 2, which has previously been amplified from feline cutaneous SCC. However, the other sequence has not previously been reported, suggesting a novel feline papillomavirus.

CLINICAL RELEVANCE: There is evidence that papillomaviruses promote the development of SCC on sun-exposed skin in humans. This is the first report in a cat of a papillomavirus other than FdPV2 and the first time that multiple papillomaviruses have been detected within a single neoplasm in this species. Whether the papillomaviruses influenced the development and behaviour of this SCC is currently uncertain, but this case provides additional evidence of the association between papillomaviruses and feline cutaneous SCC. If papillomaviruses are found to influence the development of SCC this may allow novel strategies to prevent these common neoplasms in cats.  相似文献   
52.
Abstract

CASE HISTORY: A 2-year-old Hereford bull was lame for one week before becoming recumbent.

CLINICAL AND PATHOLOGICAL FINDINGS: The scrotum and ventral perineal region were cold and blackened caudally. The semimembranosus and semitendinosus muscles were firm on palpation. The bull was subject to euthanasia, and necropsy revealed that the skin and S/C tissues of the caudal half of the scrotum were grey and necrotic. The caudal and distal aspects of the semimembranosus and semitendinosus muscles were grey and necrotic to a depth of approximately 15 cm, and these changes appeared to track along fascial planes. The tissue had an offensive smell, and large amounts of flocculent, watery, brown fluid and some gas were present. Histology of affected muscle and S/C tissues revealed coagulative necrosis, with oedema and large numbers of bacteria that were predominantly Gram-positive rods. Adjacent blood vessels contained thrombi while the epidermis overlying the affected areas appeared diffusely necrotic, suggesting infarction. Culture of the fluid yielded a pure growth of Arcanobacterium spp., which was identified as Arcanobacterium haemolyticum, using an API Coryne biochemical test strip.

DIAGNOSIS: Necrotising fasciitis and myositis due to Arcanobacterium haemolyticum.

CLINICAL RELEVANCE: Arcanobacterium haemolyticum has not previously been reported as a cause of necrotising fasciitis in any species. Necrotising fasciitis is probably an under-reported condition in cattle due to its clinical similarity to clostridial disease.  相似文献   
53.
The main objective of the present work was to study the effect of cryopreservation of European eel sperm both on the sperm viability and the spermatozoa head morphology. Spermatozoa morphology was evaluated with computer-assisted morphology analysis after collection in fresh samples, after adding the freezing medium containing dimethyl sulfoxide as cryoprotectant and, finally, after the cryopreservation process and thawing. Cell viability was assessed, in both fresh and thawed samples, by Hoechst 33258 staining. Computer-assisted sperm analysis (CASA) was used to determine the percentage of motile cells and to measure motility parameters in sperm samples. A significant decrease of head perimeter (12.56%) and area (17.90%) was detected from spermatozoa in fresh to thawed samples, indicating that cells do not recover the original size after the cryopreservation process. CASA was used to measure the percentage of motile cells (51.9%) and spermatozoa motility parameters such as curvilinear, straight line and angular path velocities, as well as beating cross frequency. This technique was employed in the fresh sperm samples but proteins present at the freezing medium (L-alpha-phosphatidylcholine) made impossible to use this last technique in thawed samples. When sperm viability was assessed by Hoechst staining, a significant decrease of approximately 15% (73.10 vs 58.26%) of alive spermatozoa was registered from fresh to thawed samples. The percentage of motile cells measured by CASA in fresh samples (51.9%) was lower than the percentage of alive cells determined by Hoechst stainning, suggesting the existence of different batches of spermatozoa in different stages of development, even during the eight to tenth weeks of treatment, when the highest sperm quality was found.  相似文献   
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An extensive field comparison of the gamma interferon (IFN-gamma) assay and the single intradermal tuberculin test for the diagnosis of bovine tuberculosis was conducted in Australia. The specificity of the IFN-gamma assay was determined by testing more than 6000 cattle from tuberculosis-free herds and varied from 96.2% to 98.1%, depending on the cut-off point chosen to define a positive reactor. For the sensitivity trial, cattle from herds being de-populated because of bovine tuberculosis were examined with both assays. The sensitivity of the IFN-gamma assay was shown to be significantly higher than the single intradermal tuberculin test and varied from 76.8% to 93.6% depending on the method of interpretation. A maximum overall sensitivity of 95.2% was obtained by testing with the IFN-gamma and the tuberculin test in parallel. The superior sensitivity of the IFN-gamma assay and the ability to adjust the sensitivity of the system depending on the task involved, will provide the Australian Tuberculosis Eradication Campaign with a valuable additional test to enable it to accomplish its goals.  相似文献   
57.
The echocardiographic effects of medetomidine and xylazine were evaluated in 6 healthy dogs. Values for echocardiographic variables were significantly different from pre-treatment values after administration of both drugs. The effects of medetomidine were similar to that of xylazine. Because of their cardiac depressant effects, both drugs should be used with care in sick dogs.  相似文献   
58.
Abstract

AIMS

To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand.  相似文献   
59.
Gonotrophic dissociation, a condition in which the ovaries remain undeveloped in female mosquitoes that have taken a full blood meal, occurs in Culex pipiens L., when incubated at low temperature (10 degrees to 15 degrees C) with short photoperiod and held at low temperature after feeding. Gonotrophic dissociation occurred sporadically in Culex quinquefasciatus Say after conditioning by low temperature, irrespective of photoperiod. Two major considerations are posed: first, the importance of gonotrophic dissociation to hibernation potential; and, second, the potential of a hibernating female mosquito to serve as a virus reservoir.  相似文献   
60.
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