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21.
Canine hypothyroidism   总被引:3,自引:0,他引:3  
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22.
Bilateral hypoplasia of the soft palate and aspiration pneumonia occurred in a Standardbred foal. The filly was presented with a history of illthrift, dyspnoea, coughing and bilateral nasal discharge. Abnormal sounds (crackels and wheezes) were auscultated over all lung fields and the cervical trachea. Endoscopy revealed a shortened soft palate with a uvula-like mass protruding from the free border into the nasopharynx. Mucopurulent material was present in the trachea. Samples obtained by tracheal wash were submitted for cytology, culture and sensitivity testing. Results indicated a septic inflammatory process. On lateral radiographs of the thorax there were patchy areas of consolidation and air bronchograms. The foal was euthanased. Necropsy confirmed the presence of a palatal defect and aspiration pneumonia of moderate severity. No other congenital abnormalities were present.  相似文献   
23.
Three groups of eight normal dogs each were orally given prednisone at doses of 0.22 mg/kg of body weight/day, 0.55 mg/kg/day, or 1.1 mg/kg on alternate mornings. Four dogs served as nontreated controls. Samples were obtained from members of each group to determine baseline serum cortisol and ACTH-stimulated cortisol values and histologic features in the lateral thoracic skin before prednisone administration, and after 1, 2, 3, and 4 weeks of administration. Some animals from each group were necropsied after 1, 2, 3, and 4 weeks of prednisone administration. Each course of prednisone administration resulted in adrenocortical atrophy and hypofunction, but adrenocortical suppression was less severe and slower in onset in the group given prednisone on alternate days. Extra-adrenal effects observed were atrophy of the skin and focal, fatty change of the liver. These changes were most evident in dogs given daily pharmacologic doses of prednisone (0.55 mg/kg/day). Fewer extra-adrenal effects were observed in dogs given alternate-day therapy. There were no extra-adrenal lesions in the dogs given equivalent glucocorticoid replacement doses (0.22 mg/kg/day).  相似文献   
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25.
The presence of anovulatory haemorrhagic follicles during the oestrous cycle of mares causes financial impacts, slowing conception and increasing the number of services per pregnancy. Non‐steroidal anti‐inflammatory drugs (NSAIDs) such as meloxicam and phenylbutazone are used in the treatment of several disorders in mares, and these drugs can impair the formation of prostaglandins (PGs) and consequently interfere with reproductive activity. This study aimed to evaluate the effects of treatment with NSAIDs on the development of pre‐ovulatory follicles in mares. In total, 11 mares were studied over three consecutive oestrous cycles, and gynaecological and ultrasound examinations were performed every 12 h. When 32‐mm‐diameter follicles were detected, 1 mg of deslorelin was administered to induce ovulation. The first cycle was used as a control, and the mares received only a dose of deslorelin. In the subsequent cycles, in addition to receiving the same dose of deslorelin, each mare was treated with NSAIDs. In the second cycle, 4.4 mg/kg of phenylbutazone was administered, and in the third cycle, 0.6 mg/kg of meloxicam was administered once a day until ovulation or the beginning of follicular haemorrhage. All of the mares ovulated between 36 and 48 h after the induction in the control cycle. In the meloxicam cycle, 10 mares (92%) did not ovulate, while in the phenylbutazone cycle, nine mares (83%) did not ovulate. In both treatments, intrafollicular hyperechoic spots indicative of haemorrhagic follicles were observed on ultrasound. Thus, our results suggested that treatment with meloxicam and phenylbutazone at therapeutic doses induced intrafollicular haemorrhage and luteinization of anovulatory follicles.  相似文献   
26.
Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, and momentum across the land-atmosphere interface to be specified. These fluxes are calculated by submodels called land surface parameterizations. Over the last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations of the global soil-vegetation-atmosphere transfer system as advances in plant physiological and hydrological research, advances in satellite data interpretation, and the results of large-scale field experiments have been exploited. Some modern schemes incorporate biogeochemical and ecological knowledge and, when coupled with advanced climate and ocean models, will be capable of modeling the biological and physical responses of the Earth system to global change, for example, increasing atmospheric carbon dioxide.  相似文献   
27.
As a result of anatomic and physiologic differences, draft breeds may be at greater risk of developing anesthetic complications. The aim of the study was to evaluate and compare anesthetic management of draft (DR) and light (LT) horses. A case‐matched retrospective study of 371 clinical case records of DR (124 cases) and LT (247 cases) horses presented for general anesthesia between 1991 and 1998 was performed. Data were tabulated and comparisons were made using Student's t‐test (significance p < 0.05). Prior to induction, there were significant differences in mean body weight, rectal temperature, PCV, RBC, and serum TP concentration between DR and LT breeds. There were differences in mean doses of pre‐operative butorphanol (LT 21 µg kg?1; DR 17 µg kg?1), induction guaifenesin (LT 99 mg kg?1; DR 88 mg kg?1), and intraoperative ketamine (LT 0.35 mg kg?1; DR 0.56 mg kg?1) required. There were no significant differences in the mean doses of pre‐operative xylazine, detomidine, or induction barbiturate administered. The mean, average, and maximum concentrations of inspired halothane were significantly higher for DR than for LT horses. Draft horses received 33% less intraoperative IV fluids (8.2 mL kg?1 hour?1) than LT horses. Mean anesthetic duration, time to extubation, and standing recovery were not significantly different. Induction complications were not reported for either group. Rates of occurrence of intraoperative bradycardia, hypercarbia, hypoxemia, and metabolic acidosis (SBE, TCO2, and bicarbonate concentration) did not differ significantly. Average MAP was greater in DR horses, but neither the degree nor the mean duration of hypotension differed between DR and LT horses. Mean PaO2 was significantly lower in DR (246 mm Hg, 32.8 kPa) than in LT (305 mm Hg, 40.7 kPa) breeds. Draft horses were at greater relative risk of hypoventilation than LT horses. The greater MAP and requirement for halothane and intraoperative ketamine may indicate problems in achieving and maintaining a surgical plane of anesthesia. Draft horses may be at a greater risk of ventilation–perfusion mismatching.  相似文献   
28.
AIM: To investigate the nature of a neurological disease in Wiltshire sheep.

METHODS: Three affected lambs were examined, humanely killed and necropsied. Selected neurological tissues were examined by light and electron microscopy.

RESULTS: Primary neurological lesions were confined to the cerebellum and were characterised by loss of Purkinje cells and the presence of large hypertrophied dendrites of surviving Purkinje cells. These contained stacks of smooth endoplasmic reticulum. There was hyperplasia and cell swelling of Bergmann glia. Mild Wallerian-type degeneration affected white matter in the cerebellum and spinal cord.

CONCLUSION: The cerebellar lesions were of a degenerative and reactive rather than hypoplastic nature. These, and the history, suggest a genetic cause with putative inheritance as an autosomal recessive trait. Accordingly, the disorder is described as a cerebellar abiotrophy.  相似文献   
29.
Abstract

AIMS: To measure the magnitude and variability in production responses to anthelmintic treatments administered to adult ewes around lambing.

METHODS: Ewes carrying twin lambs, from sheep and beef farms (eight in Year 1 and six in Year 2) in the Wairarapa region of New Zealand, were enrolled in 14 trials (part of an experiment carried out on one farm in one year). Experiment 1 compared ewes treated 2–4?weeks pre-lambing with a controlled release capsule (CRC) containing abamectin, albendazole, Se and Co, to ewes injected pre-lambing with a long-acting Se plus vitamin B12 product, and to untreated ewes. Experiment 2 included these treatments, plus a CRC administered at pregnancy scanning. Experiment 3 included the same treatments as Experiment 1, plus administration of a CRC containing albendazole, Se and Co, injectable moxidectin or oral derquantel plus abamectin, all administered pre-lambing, or oral derquantel plus abamectin administered 4–6?weeks after lambing. Variables compared were ewe liveweight at weaning and pre-mating, lamb liveweight at weaning, total weight of lamb weaned per ewe and ewe dag score at weaning.

RESULTS: Ewes treated with a CRC pre-lambing were heavier than untreated ewes (mean 3.2?kg) at weaning in 12/14 trials, and pre-mating (mean 2.8?kg) in 9/14 trials (p<0.001). Compared with mineral-treated ewes the mean difference was 2.8?kg pre-lambing (9/14 trials) and 1.7?kg pre-weaning (6/14 trials). Lambs reared by treated ewes were heavier (mean 1.55?kg) at weaning in 6/14 trials (p<0.001), but there was no effect of CRC treatment on total weight of lambs weaned per ewe (p=0.507). Variation in weight of lamb weaned per ewe was largely explained by differences in lamb survival from birth to weaning (p<0.001), with no effect of CRC treatment (p>0.65).

Treatment of ewes with a CRC at pregnancy scanning was neither better nor worse than a pre-lambing treatment (p=0.065).

There was no difference in the response from treatment with either of the two CRC or moxidectin. Treatment with short-acting oral anthelmintics resulted in no consistent benefit.

CONCLUSIONS: Anthelmintic treatments administered to ewes around lambing resulted in variable responses between farms and years, which in some trials were negative for some variables, and some of the variability was due to the mineral component of the CRC. The widespread perception amongst farmers and veterinarians that anthelmintic treatment of ewes around lambing will always result in positive benefits is not supported.  相似文献   
30.
Adverse reactions to intramuscular injections of procaine penicillin G are reported in 11 horses, five of which died. The clinical findings are presented and suggest central nervous involvement in most cases. Post mortem findings in one horse were consistent with anaphylaxis whereas in other cases the clinical findings, duration of treatment, speed of onset and subsequent completion of treatment supports diagnosis of an acute procaine toxicity syndrome.  相似文献   
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