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991.
A 2-yr grazing performance study was conducted in Eastern Colorado to evaluate the effects of feeding raw cull beans (Phaseolus vulgaris) or canola meal, compared to sunflower meal, to beef cows grazing dormant, native winter range on body weight and body condition score (BCS) change, reproductive performance, and calf performance. Ninety-five pregnant, spring-calving crossbred cows (541 +/- 51 kg) in 1995 to 1996 and 65 cows (602 +/- 60 kg) in 1996 to 1997 were randomly assigned to one of five treatments (19 and 13 cows per treatment in 1995 to 1996 and 1996 to 1997, respectively): 1) unprocessed Great Northern beans to supply 182 g/d of CP (GNB); 2) canola meal to supply 182 g/d of CP (CM); 3) a mixture of Great Northern beans and sunflower meal, each to supply 91 g/d of CP, for a total of 182 g/d of CP (MIX); 4) sunflower meal to supply 182 g/d of CP (SFM+); and 5) sunflower meal to supply 91 g/d of CP (SFM-). Cow weight and body condition performance were broken into a gestation and a lactation phase in 1995 to 1996; calves were weighed at birth, at the end of the lactation phase in April, and at weaning the following September. Only gestation performance was monitored in 1996 to 1997, and subsequent calf birth and weaning weight were recorded. The SFM- group lost more weight during the gestation phase than other treatments (P < .05), yet no differences were detected for gestation phase daily BCS change, calf birth weight, lactation phase daily weight change, lactation phase daily BCS change, first-service conception rate to AI, or overall pregnancy rate. Off-test calf weight was higher in April for calves from dams of the SFM+ and CM treatments than for calves from dams on the GNB or SFM- treatments (P < .05), and calves from cows on the CM treatment were heavier in April than calves from cows on the MIX treatment (P < .05). No differences in calf weight were present at weaning. Consumption of beans by cows on the GNB treatment was low because of palatability problems. Mixing the beans with sunflower meal in the MIX treatment eliminated this problem. Canola meal, Great Northern beans, or a combination of sunflower meal and Great Northern beans were comparable to sunflower meal as protein supplements for beef cows grazing native winter range, despite obvious palatability problems with the beans.  相似文献   
992.
993.
Two related female Norwegian Elkhounds were evaluated at 6 and 8 months of age for enlarged clitori. Both had a 78 XX karyotype. Histology of their internal reproductive tracts demonstrated 1 to be an XX true hermaphrodite with bilateral ovotestes and the other to be an XX male with bilateral aspermatogenic testes. Polymerase chain reaction-based tests of genomic DNA showed that both dogs lacked Sry, the testis-determining gene. Pedigree analysis was consistent with an autosomal recessive mode of inheritance, as has been reported in the American Cocker Spaniel and the German Shorthaired Pointer. This is the 1st reported case of familial Sry-negative XX sex reversal in the Norwegian Elkhound. A summary of 34 previously unreported cases of dogs with masculinized external genitalia and a normal 78 XX karyotype seen from 1980 to 1997 is given.  相似文献   
994.
995.
Clinical and pathologic features of thyroid tumors in 26 dogs   总被引:1,自引:0,他引:1  
Thyroid tumors were diagnosed in 26 dogs between 1977 and 1984. A total of 23 of the 26 tumors were carcinomas, and 3, detected as incidental findings at necropsy, were adenomas. The median patient age was 9.5 years. Dogs of the Beagle breed were affected most commonly (5 dogs). The most common physical abnormalities in carcinoma patients were cervical swelling, dyspnea, and coughing. A total of 25 of 26 dogs were clinically euthyroid. Aspiration cytology provided diagnostic information in 8 of 17 cases. In dogs with thyroid carcinoma, a cervical soft tissue lesion was identified consistently by use of radiography and scintigraphy with sodium pertechnetate. Pulmonary metastases were detected radiographically in 8 of 21 dogs with thyroid carcinoma. Thoracic nuclear imaging confirmed the radiographic findings in 11 of 14 dogs. Surgical excision of the thyroid mass was the primary treatment for 17 dogs with carcinoma. Eight dogs died within 2 years (median, 7 months) of surgery because of primary tumor regrowth or metastases. Four dogs were alive at a range of 3 to 48 months after surgery, and 4 dogs died from unrelated causes. Necropsy of 7 dogs with thyroid carcinoma revealed neoplastic infiltration of the cervical blood vessels and pulmonary metastases in each dog. The most common histologic patterns of thyroid carcinoma were solid or compact cellular (11 dogs) and mixed solid-follicular tumors (8 dogs). Dogs with a solid carcinoma had a median survival time of 10.5 months (6 dogs), and dogs with a mixed solid-follicular tumor had a median survival time of 8 months (3 dogs).  相似文献   
996.
Two cases of peracute haemorrhagic enteritis in the dog are reported. Gram-positive bacilli, which were shown in one case to be Clostridium welchii were found adhering to the necrotic epithelial surfaces in parts of the gastrointestinal tract in both cases. Large numbers of C welchii were recovered from the intestines of both dogs.  相似文献   
997.
A series of incidents involving greylag goose (Anser anser) casualties in Angus and Perthshire and a single incident involving pink-footed goose (Anser brachyrhynchus) casualties on Humberside occurred during the winter of 1974/75. The results of post-mortem examinations and brain esterase studies were consistent with the deaths having resulted from organophosphorus poisoning. Chemical analysis revealed the presence of carbophenothion (S-4-chlorophenylthiomethyl OO-diethyl phosphoro-dithioate) residues in the gut contents and internal tissues of the casualties. It was concluded that the geese had died from carbophenothion poisoning following the ingestion of treated winter wheat seed and the factors that led to the incidents are discussed.  相似文献   
998.
999.
OBJECTIVE: To describe neuroendocrine responses that develop in dogs subjected to prolonged periods of ventricular pacing. ANIMALS: 14 adult male hound-type dogs. PROCEDURE: Samples were obtained and neuroendocrine responses measured before (baseline) and after 3 periods of ventricular pacing. A pacemaker was used to induce heart rates of 180, 200, and 220 beats/min (BPM). Each heart rate was maintained for 3 weeks before increasing to the next rate. Atrial natriuretic peptide, antidiuretic hormone, aldosterone, norepinephrine, epinephrine, and dopamine concentrations and plasma renin activity were measured. Severity of left ventricular compromise was estimated. RESULTS: Shortening fraction decreased significantly with increasing heart rates (mean +/- SE, 35.5 +/- 1.4, 25.0 +/- 1.4, 19.5 +/- 1.9, and 12.2 +/- 2.3 for baseline, 180 BPM, 200 BPM, and 220 BPM, respectively). Atrial natriuretic peptide concentrations increased significantly at 180 BPM (44.1 +/- 3.0 pg/mL) and 200 BPM (54.8 +/- 5.5 pg/mL), compared with baseline concentration (36.8 +/- 2.6 pg/mL). Dopamine concentration increased significantly at 200 BPM (70.4 +/- 10.4 pg/mL), compared with baseline concentration (44.2 73 pg/mL). Norepinephrine concentrations increased significantly from baseline concentration (451 +/- 46.2 pg/mL) to 678 +/- 69.8, 856 +/- 99.6, and 1,003 +/- 2676 pg/mL at 180, 200, and 220 BPM, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs subjected to ventricular pacing for 9 weeks developed neuroendocrine responses similar to those that develop in humans with more chronic heart failure and, except for epinephrine concentrations, similar to those for dogs subjected to ventricular pacing for < 6 weeks.  相似文献   
1000.
OBJECTIVE: To investigate the potential use of fluorescent-labeled annexin V, anti-human fibrinogen antibody, and anti-human thrombospondin antibody for detection of the activation of equine platelets by use of flow cytometry. SAMPLE POPULATION: Platelets obtained from 6 Thoroughbreds. PROCEDURE: Flow cytometry was used to assess platelet activation as indicated by detection of binding of fluorescent-labeled annexin V, anti-human fibrinogen antibody, and anti-thrombospondin antibody to unactivated and ADP-, collagen-, platelet activating factor (PAF)-, and A23187-activated equine platelets. Human platelets were used as control samples. Determination of 14C-serotonin uptake and release was used to assess the extent of platelet secretion. RESULTS: Anti-human thrombospondin antibody failed to bind to equine platelets. Annexin V bound to platelets activated with PAF or A23187 when platelets had undergone secretion. Anti-human fibrinogen antibody bound to ADP-, PAF-, and A23817-activated platelets, but binding was not dependent on platelet secretion. The extent of binding of anti-fibrinogen antibody was less in equine platelets, compared with that for human platelets, despite maximal stimulation. CONCLUSIONS AND CLINICAL RELEVANCE: Activation of equine platelets can be detected by use of fluorescent-labeled annexin V and anti-human fibrinogen antibody but not by use of anti-human thrombospondin antibody. These flow cytometric techniques have the potential for detection of in vivo platelet activation in horses at risk of developing thrombotic disorders.  相似文献   
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