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1.
An eight-year-old neutered female Persian cat with a four-year history of relapsing skin disease, characterised by ulcerated nodules with a yellow granular discharge, was examined. A diagnosis of granulomatous dermatitis and panniculitis (pseudomycetoma) caused by Microsporum canis was made on the basis of history, clinical signs, histopathological examination of skin biopsy specimens and culture of macerated tissue. Because previous therapy, comprising repeated surgical excision and the administration of griseofulvin and itraconazole, had not been successful, terbinafine was administered for an eight-month period. However, lesions progressed despite this treatment and the cat was euthanased.  相似文献   
2.
The efficacy of controlled-release melatonin implants to advance the onset of the breeding season was assessed in 1-year-old red deer hinds on five commercial deer farms in various localities in the North Island of New Zealand. Between 44 and 60 hinds in each of six herds were equally divided among treatment and control groups at each site. Melatonin treatment commenced between 27 November and 16 December and was achieved by the subcutaneous administration of two 18 mg melatonin implants. Three doses were given at about 30 day intervals. Two adult stags for each hind group were treated with three 18 mg melatonin implants concurrently on either two or three occasions. On each property, treated and control hinds were joined as one herd to treated stags commencing 30 January-10 February and concluding 15 May-2 June. The hinds in the four experimental herds underwent rectal ultrasound examination May-June to estimate conception rate and foetal age. Calving dates, hind and calf mortalities, weaning weights, and the antler growth cycle and harvesting data were recorded. Overall, treatment with melatonin resulted in an average advance of the median calving date of 22 days (range 12-36 days) when compared with untreated controls in the same herds. Pregnancy rates were 91.3-100% in treated hinds and 63.6-100% in untreated hinds. There were no differences in calf mortality or calf sex ratio between treated and untreated groups. No hind deaths could be attributed to melatonin treatment. The weaning weights of calves were 5.68 kg and 4.43 kg heavier for the male and female offspring of treated hinds respectively, compared with those of control hinds. Treated stags commenced rutting behaviour earlier than normal and the antler casting and growth cycle was advanced. Treatment resulted in advancement of the seasonal pattern of coat changes in hinds and stags, but no untoward side effects of the melatonin treatments were observed.  相似文献   
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Cooling stored epididymal samples for several days allows facilities to transport and process genetic material post‐mortem. Improvements to this practice allow the preservation of sperm from domestic cats, which are the ideal study model for wild felids. However, the modifications in spermatic features and the oxidative profile are not fully understood in cats. This information is necessary for the development of biotechniques, such as new extenders for cryopreservation. Therefore, the purpose of this study was to evaluate the spermatic and oxidative profile in samples from the epididymal cauda of domestic cats cooled at 5°C for 24, 48 and 72 hr. Spermatozoa were collected from the epididymis cauda. Evaluations consisted of computer‐assisted sperm analysis (CASA), plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, sperm DNA integrity (toluidine blue), mitochondrial activity (3′3 diaminobenzidine), activity of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), measurement of lipid peroxidation (TBARS) and protein oxidation. A decrease in sperm motility parameters was observed after 72 hr of cooling (i.e. total and progressive) with a higher percentage of minor (37.7 ± 6.3%) and total defects (53.4 ± 6.3%). Additionally, a decrease in high mitochondrial activity (Class I: 16.6 ± 2.2%) occurred after 72 hr. The decrease in motility rates after a long cooling time probably was caused by the increase in sperm abnormalities. A long cooling time causes cold shock and mitochondrial exhaustion, but there was no observed change with the oxidative stress condition. Therefore, cat epididymal sperm stored at 5°C appear to maintain a high quality for up to 48 hr of cooling time.  相似文献   
6.
Sperm DNA fragmentation is a condition that interferes directly in the reproductive efficiency. Currently, there are several methods for assessing the sperm DNA integrity, such as Alkaline Comet, TUNEL and Sperm Chromatin Structure Assay. However, many of these techniques are laborious and require high‐precision equipment. Thus, the development of new techniques can optimize the evaluation of sperm DNA damage. Therefore, the aim of this study was to standardize the toluidine blue (TB) stain technique for the analysis of DNA fragmentation of dog, cat, bull, stallion and ram spermatozoa. For this purpose, we used six animals of each specie (n = 30), in reproductive age. Sperm was collected by different methods according to the particularities of each species, and such samples were divided into two aliquots: a sperm sample was kept at 5°C (considered as intact sperm DNA), and the remaining samples were submitted to the induction of DNA fragmentation by exposure to ultraviolet light for 4 hr. Samples were then mixed with the intact sample to obtain known and progressive proportions of sperm with fragmented DNA (0%, 25%, 50%, 75% and 100%). Semen smears were performed and subjected to staining with TB. Blue‐stained spermatozoa were considered to have DNA fragmentation. We observed high linear regression coefficients between the expected proportion of damaged DNA and the results of TB for dog, cat, ram, bull and stallion samples. In conclusion, TB stain was considered a fast and effective technique for the study of spermatozoa DNA in several species.  相似文献   
7.
In the mid- to late 1980s, supercritical fluid chromatography (SFC) was ‘reborn’ as a technique for the 1990s. Supercritical fluids have physical properties (viscosity, diffusivity and density) intermediate between those of licuids and gases. Analyte solubilities are similar to those in some liquid chromatography solvents and the gas-like properties of supercritical fluids make higher resolution or shorter analysis times possible. Applications and experience with a home-built SFC system, as well as methods developed elsewhere, are described. The successes and limitations of the technique are reviewed together with details of the instrumentation. Areas in which SFC may become the procedure of choice include multi-residue methods, non-polar analyses, micro-preparative uses and for difficult extractions. The advances in GC and HPLC technology, however, lead us to believe that SFC will remain a specialist technique, appealing only to a minority of analysts.  相似文献   
8.
W. Bond 《Phytoparasitica》1992,20(1):S77-S81
Concern about herbicide safety has renewed interest in non-chemical systems of weed control. Alternative approaches for dealing with weeds can be broadly grouped into cultural and biological methods. Some of the options available for controlling weeds without the use of herbicides are discussed.  相似文献   
9.
Serum immunoglobulin G (IgG) responses of healthy dogs and dogs with Malasseziapachydermatis dermatitis were compared by Western immunoblotting. M pachydermatis CBS 1879 was disrupted mechanically and its proteins were separated and blotted on to nitrocellulose membranes before being incubated with sera from eight healthy beagles, eight Irish setters with gluten-sensitive enteropathy, 15 healthy basset hounds, and 30 dogs with Mpachydermatis-associated dermatitis, 20 of which were basset hounds. The mean (se) numbers of bands of immunoreactivity observed in the seborrhoeic basset hounds (10.7 [0.4]) and affected mixed-breed dogs (9.4 [0.9]) were significantly greater than in the beagles (3-0 [1.0]), Irish setters (5.5 [1.1]) and healthy basset hounds (5.6 [0.7]). The number of bands identified was correlated (r(s) = 0.76, P < 0.001) with the anti-M pachydermatis IgG values measured by ELISA in a previous study. Most of the dogs were immunoreactive towards the 132, 66 and 50 to 54 kDa proteins and the affected dogs were also usually reactive towards the 219, 110, 71 and 42 kDa proteins.  相似文献   
10.
This study aimed to investigate the distribution of Malassezia species yeasts on the skin of healthy horses. Acetate tape samples were obtained from the lip, axilla, interbulbar region, groin and anus of 12 healthy horses. The samples were stained and examined microscopically and sites harbouring yeast-like organisms were identified. Contact plates were applied to the skin at these sites and cultured at 26 degrees C and 32 degrees C. No growth was obtained on horse blood, Sabouraud's dextrose or modified Dixon's agar. A pure growth of a Malassezia-type organism was obtained on Sabouraud's dextrose agar enriched with oleic acid when it was incubated at 30 degrees C. It was identified by 26S ribosomal DNA D1/D2 sequence analysis as a member of the genus Malassezia, and most closely related to Malassezia sympodialis. However, the level of sequence divergence indicated that it was a novel species.  相似文献   
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