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121.
Mechanical and insect feeding injuries of cabbage provided sites for ingress by Sclerotinia sclerotiorum. In field studies, injuries sustained by hitting cabbage heads with a blunt object penetrated several leaf layers and were readily infected by S. sclerotiorum. Incidence of Sclerotinia rot ranged from 15 to 36% infected plants in the hitting treatment. Disease incidence was low (0–5%) when wounds were created by allowing lepidopterous larvae (the imported cabbageworm, Pieris rapae L., the diamondback moth, Plutella xylostella L., and the cabbage looper, Trichoplusia ni Hubner) to feed on cabbage leaves. The incidence of colonization of lepidopterous larvae feeding sites by S. sclerotiorum was greater in greenhouse studies (5–60% infected feeding sites) than in field studies. In greenhouse studies, disease incidence was significantly greater in plants receiving hitting injuries than tearing injuries. There was little evidence of inoculation day or injury day effects. Colonization frequency of tissue injured mechanically was similar whether wounds were inoculated immediately or 4 days later. Plants that were incubated in a dry environment developed fewer infections than plants held in a moist environment. Inoculated plants that were not injured did not develop disease.  相似文献   
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123.
Heart rate as a measure of adaptation to stress in cattle   总被引:1,自引:0,他引:1  
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124.
A 1‐year‐old, previously spayed phenotypic female Poodle/Soft‐coated Wheaten Terrier (Whoodle) cross was presented for a suspected ovarian remnant. Serum luteinizing hormone (LH) concentration was below the detection limit (<1 ng/ml Witness® LH), and serum progesterone concentration was elevated in the chemiluminescence immunoassay (CLIA; 20 ng/ml), consistent with dioestrus and presence of ovarian tissue. Transabdominal ultrasound revealed a retroperitoneal soft tissue structure suspected to be a gonad. On exploratory laparotomy, a gonad was removed from the cranial retroperitoneum, cranial to the right kidney, after ligation of its primary blood supply. Histological examination proved the gonad to be an ovotestis. Subsequent cytogenetics revealed a 78 XX karyotype, thus confirming the diagnosis of ectopic ovotestis in a XX ovotesticular, SRY‐negative, disorder of sexual development in a dog.  相似文献   
125.
Factors associated with the proportion of sheep cured of virulent footrot after antibiotic treatment were studied in a field trial under dry environmental conditions. From 2 similar flocks, 1091 Merino sheep weighing about 50 kg and infected with virulent footrot received an intramuscular injection of either 12 mL of a mixture of penicillin (250 mg/mL) and streptomycin (250 mg/mL), 6 mL of long acting oxytetracycline (200 mg/mL) or 6 mL of a mixture of lincomycin (50 mg/mL) and spectinomycin (100 mg/mL). Variables that were significantly associated with the proportion of sheep cured were: the type of antibiotic used, the number of feet infected and the flock from which the sheep came. There was an interaction between antibiotic type and number of feet infected and between antibiotic type and flock in association with the proportion of sheep cured. The extent of paring and the occurrence of blowfly strike in footrot lesions treated with diazinon had no significant association with the proportion of sheep cured.  相似文献   
126.
Two dogs with signs of right-sided congestive cardiac failure, due to recurrent pericardial effusion secondary to the presence of intraperi-cardial neoplasia, were treated by percutaneous balloon pericardiotomy. The first patient was euthanased one month after the procedure while the second patient developed ascites as a result of obstruction of the caudal vena cava by the growing tumour and was euthanased 14 weeks after the procedure. In neither case was there a recurrence of a significant volume of the effusion. Percutaneous balloon pericardiotomy represents an effective means of relieving recurrent malignant pericardial effusion, without resorting to thoracotomy.  相似文献   
127.
128.
Treatment of clinical cases of heart failure in dogs, using frusemide, was associated with statistically significant reductions in plasma concentrations of potassium, magnesium, sodium and chloride, compared with healthy controls and untreated dogs with dysrhythmias. The reductions in sodium and chloride seem too slight to be clinically significant but those in magnesium and potassium could potentially have harmful effects, including the induction of cardiac dysrhythmias. Indeed, diuretic-treated dogs with ventricular ectopic beats in their electrocardiograms had significantly lower plasma potassium concentrations than other dogs undergoing diuretic treatment. As potassium and magnesium are predominantly intracellular cations, the falls in plasma concentration may well be associated with substantial deficits within cells, including those of the myocardium.  相似文献   
129.
130.
Objectives : To retrospectively assess the long‐term outcome for dogs that were presented with collapse, syncope or exercise intolerance for which an underlying cause is not identified. Methods : The clinical records of animals presenting to two practices were assessed. Dogs which presented for collapse, syncope or exercise intolerance at least 6 months previously and did not receive a definitive diagnosis despite investigation were included. Follow‐up of these cases was carried out by conducting telephone interviews with the owners. Results : One hundred and fifty‐three cases were successfully followed up. Clinical signs had resolved in 64 cases (42%), 35 dogs (23%) were continuing to exhibit clinical signs, although 22 of these had improved without medical intervention. In 17 cases (11%), a diagnosis had subsequently been made or treatment was being administered and 37 dogs (24%) had died. Of the deaths, 18 (12%) were considered to be related to the original presentation. The overall prevalence of death and deterioration related to the problems investigated was 16·2% of cases. Death in boxers was significantly more common than in other breeds (36%). Clinical Significance : Death and deterioration are uncommon outcomes for dogs other than boxers presenting with collapse, syncope and exercise intolerance for which a definitive diagnosis cannot be made.  相似文献   
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