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971.
P H J?rgensen K J Handberg P Ahrens H C Hansen R J Manvell D J Alexander 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(6):381-387
The epidemiology of an outbreak of Newcastle disease in a population of approximately 12,000 free-living pheasants (Phasianus colchicus) on the island of Faen? in Denmark in 1996 is described. The mortality during the epizootic was 56%. The spread of the disease between 7 groups of pheasants could be demonstrated over an observation period of 3 weeks. A total of 70 avian paramyxovirus serotype 1 (APMV-1) isolates was made from the flock. The intra cerebral pathogenicity indices of the 4 isolates tested were in the range 1.78-1.88. By means of immunoperoxidase monolayer assay with murine monoclonal antibodies and sequence analysis of an RT-PCR amplified segment of the F0 viral protein it was found, that the virus belonged to the highly virulent C1 antigenic group and that the amino acid sequence at the F0 cleavage site corresponded with the sequences of virulent APMV-1 strains. Based on the epidemiological circumstances it is believed that the virus was transmitted to the pheasants by feral birds. 相似文献
972.
L J Smith P F Moon V M Lukasik H N Erb 《American journal of veterinary research》1999,60(9):1047-1050
OBJECTIVE: To describe onset and duration of neuromuscular blockade induced by mivacurium chloride and its associated hemodynamic effects at 3 dosages in healthy dogs. ANIMALS: 7 Labrador Retrievers. PROCEDURE: Anesthesia was induced with thiopental and maintained with halothane in oxygen, and dogs were mechanically ventilated to end-tidal P(CO)2 between 35 and 40 mm Hg. Core temperature, end-tidal P(CO)2, and halothane concentration were kept constant throughout the experiment. Neuromuscular function was assessed by evaluation of the train-of-four response to a supramaximal electrical stimulus of 2 Hz applied to the ulnar nerve every 10 seconds. Blood for determination of plasma cholinesterase activity was obtained prior to administration of mivacurium, a bolus of which was administered IV, using a randomized Latin-square design for dosages of 0.01, 0.02, and 0.05 mg/kg of body weight. RESULTS: All dogs had typical plasma cholinesterase activity. After administration of mivacurium, differences were not evident between groups in heart rate, systolic, mean, or diastolic blood pressure, change at any time in heart rate, systolic, mean, or diastolic blood pressure, or pH. Interval from onset to 100% neuromuscular blockade was 3.92+/-1.70, 2.42+/-0.53, and 1.63+/-0.25 minutes at dosages of 0.01, 0.02, and 0.05 mg/kg, respectively. Duration of measurable neuromuscular blockade was 33.72+/-12.73, 65.38+/-12.82, and 151.0+/-38.50 minutes, respectively. Time of onset and duration of effect differed significantly among dosages. CONCLUSIONS AND CLINICAL RELEVANCE: Mivacurium provides good hemodynamic stability at the dosages tested. In dogs, this drug has a rapid onset and long duration of effect. 相似文献
973.
J Miyagi K Tsuhako T Kinjo T Iwamasa Y Kamada T Kinju Y Koyanagi 《Veterinary pathology》1999,36(5):452-456
A 37-year-old female orangutan died at the zoological garden. Autopsy examination demonstrated severe coxsackievirus B4 myocarditis immunohistochemically as a cause of the death. Apoptosis of the cardiac muscle cells was observed using the TdT-mediated dUTP-biotin nick endo labeling method and was considered to play a role in the myocarditis. Congestion of the liver and both lungs due to cardiac failure was also observed. Coxsackievirus infection is found frequently in the Okinawan human population. The present orangutan's infection might have come from visitors who were allowed to go near the orangutan. Malignant tumors, severe suppurative infections, and intestinal parasite infections were not observed. Epstein-Barr virus DNA was detected in lymph nodes, but there was no Burkitt's lymphoma. 相似文献
974.
975.
976.
C H Lamar J J Turek G D Bottoms J F Fessler 《American journal of veterinary research》1986,47(4):956-958
Certain in vitro culture conditions were determined for equine endothelial cells obtained from the aorta and pulmonary arteries. Cells were enzymatically isolated from the vessel lumen, using clostridial collagenase (2.5 mg/ml of Hanks's balanced salt solution) incubated at 37 C for 30 minutes. Cells were cultured in alpha minimum essential medium supplemented with plasma-derived and nonplasma-derived bovine fetal sera, endothelial cell-growth supplement, heparin, and antibiotics. Smooth muscle cell growth was not inhibited with nonplasma-derived animal sera, plasma-derived equine serum, or heparin. Heparin and a serum replacement were toxic to the cells used in the present study. Statistically significant differences were not found between the various media supplements. 相似文献
977.
Adult cockerels of a commercial egg-producing strain did not develop liver haemorrhages when maintained for 12 weeks on a diet containing 400 g rapeseed meal/kg food. Haemorrhages occurred in 43% of laying hens of the same strain as the cockerels and 33% of laying hens of another strain maintained on the same diet for the same period. Oestrogenisation of the male birds did not influence the incidence of haemorrhage. 相似文献
978.
Influence of laying on iron metabolism in quail 总被引:3,自引:0,他引:3
Haematological and iron content values for liver, spleen, intestines, blood, ovary and eggs were determined in female quails, from the prelaying state to full laying. A drop in hematocrit, haemoglobin and in the liver stores occurred at the onset of laying (48 to 51 d of age), but these values recovered after 5 to 10 d. The iron lost in eggs (0.3 mg Fe/egg) was responsible for this. An active homeostatic control must be necessary to supply adequate iron for both eggs and blood formation. Quails fed on an iron-deficient diet distributed iron preferentially to the haematopoietic processes, at the expense of the iron content of the eggs and a subsequent reduction of viability. 相似文献
979.
Effects of marginal selenium deficiency and winter protein supplementation on growth, reproduction and selenium status of beef cattle 总被引:4,自引:0,他引:4
Seventy-two Hereford X Simmental cows, averaging 498 kg in body weight and 5.2 yr of age, were used in a 2-yr study to ascertain if selenium (Se)-vitamin E (E) injections and winter protein supplementation would affect growth, reproduction and health of beef cattle maintained year-round on feedstuffs marginally deficient in Se (.03 to .05 mg/kg). Cows received either no injection or a mixture of 30 mg Se (as sodium selenite) and 408 IU E injected subcutaneously beginning 3 to 4 mo prepartum and at 60-d intervals throughout the 2-yr period. Calves born to Se-E treated cows were injected with 5.5 mg Se and 75 IU E/100 kg body weight at 60-d intervals beginning at 1 mo of age. Calves were born between December 30 and February 20 and cows were bred between March 20 and May 20. Cattle grazed pasture (.05 mg Se/kg) that consisted of orchardgrass, bluegrass and white clover during the fall, spring and summer. During winter (December 15 to May 2), cattle were fed corn silage (.03 mg Se/kg) supplemented with either: no protein supplement (control), soybean meal or a urea-corn mixture. Cows and calves receiving Se-E had higher (P less than .01) whole blood glutathione peroxidase (GSH-Px) activity and plasma Se concentrations than controls. Selenium-E injections reduced (P less than .05) calf death losses from 15.3% to 4.2% and slightly increased (P less than .10) adjusted calf weaning weights. Hemoglobin concentrations were higher (P less than .05) in Se-E-injected supplemented calves at 1 mo of age but not at 5 or 7 mo of age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
980.
A J Paul K S Todd J P Sundberg J A DiPietro J W McCall 《American journal of veterinary research》1986,47(4):883-884
Forty-two Beagles, 14 to 15 weeks of age, were injected subcutaneously with 50 infective larvae of Dirofilaria immitis and were allotted by weight, within sex, to 6 treatment groups. Group 1 served as nonmedicated vehicle-treated controls; groups 2 through 5 were given an oral tablet form of ivermectin at dosages of 0.3 micrograms/kg, 1.0 micrograms/kg, 2.0 micrograms/kg, and 3.3 micrograms/kg at 30 days after inoculation; group 6 was given the 2.0 micrograms/kg dosage at 45 days after inoculation. Dogs were euthanatized and necropsied 154 days after treatment (day 139 for dogs in group 6) and examined for heartworms. On the numerical bases of helminths recovered in the groups, the efficacies for preventing heartworm maturation were 0% (group 2), 53.2% (group 3), 97.2% (group 4), 98.1% (group 5), and 63.8% (group 6). Drug-related adverse reactions were not detected. 相似文献