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121.
R W Morgan J Gelb C S Schreurs D Lütticken J K Rosenberger P J Sondermeijer 《Avian diseases》1992,36(4):858-870
Recombinant strains of herpesvirus of turkeys (HVT) were constructed that contain either the fusion protein gene or the hemagglutinin-neuraminidase gene of Newcastle disease virus (NDV) inserted into a nonessential gene of HVT. Expression of the NDV antigens was regulated from a strong promoter element derived from the Rous sarcoma virus long terminal repeat. Recombinant HVT strains were stable and fully infectious in cell culture and in chickens. Chickens receiving a single intra-abdominal inoculation at 1 day of age with recombinant HVT expressing the NDV fusion protein had an immunological response and were protected (> 90%) against lethal intramuscular challenge at 28 days of age with the neurotropic velogenic NDV strain Texas GB. Recombinant HVT expressing the NDV hemagglutinin-neuraminidase provided partial protection (47%) against the same challenge. Chickens vaccinated with recombinant HVT vaccines had low levels of protection against NDV replication in the trachea when challenged ocularly. Recombinant HVT vaccines and the parent HVT strain provided similar levels of protection to chickens challenged with the very virulent RB1B strain of Marek's disease virus, indicating that insertion of foreign sequences into the HVT genome did not compromise the ability of HVT to protect against Marek's disease. 相似文献
122.
L J Spicer J Klindt F C Buonomo R Maurer J T Yen S E Echternkamp 《Journal of animal science》1992,70(10):3149-3157
Prepubertal gilts of obese (n = 24) or lean (n = 24) genetic lines were injected (s.c.) daily with 0, 2, or 4 mg of porcine somatotropin (pST) for 6 wk starting at 160 d of age to determine whether pST affects follicular function. Blood and ovaries were collected at slaughter 24 h after the last injection. Surface follicles greater than or equal to 1.0 mm in diameter were counted, and pools of follicular fluid (FFL) and granulosa cells were collected from 1.0- to 3.9-mm (small) and 4.0- to 6.9-mm (medium) follicles. Oocytes were collected from small and medium follicles and evaluated for maturational stage and viability. Porcine somatotropin increased (P less than .08) the numbers of small but not the numbers of medium follicles per gilt (P greater than .10). Oocyte maturation and viability were not affected by pST or genetic line. Porcine somatotropin increased (P less than .05) concentrations of insulin-like growth factor I (IGF-I) in serum and FFL of both obese and lean gilts; IGF-I was lower (P less than .01) in lean gilts. Treatment with pST decreased (P less than .05) IGF-II in FFL of lean but not in that of obese gilts. Dose of pST and line had no effect on concentrations of progesterone in FFL of small or medium follicles or on concentrations of estradiol in FFL of small follicles.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
123.
A Pyrenophora teleomorph was recently found on barley stubble in South Africa. Single-ascospore isolates, mated on water agar containing sterile pieces of barley stubble, produced the teleomorph within 12 months of incubation at 15°C in the dark. Based on morphological characteristics and symptom expression on barley plants, the teleomorph is ascribed to P. japonica (anamorph Drechslera tuberosa ). This is the first report describing the occurrence of the teleomorph of D. tuberosa in South Africa. 相似文献
124.
A device for determining the sorptivity of soil aggregates 总被引:2,自引:0,他引:2
A device that infiltrated water over a small circular surface area having a radius ranging between 1.45 mm and 2.5 mm was used to measure the sorptivity of initially air-dry aggregates of size greater than 20 mm. The small infiltration area caused the water uptake to be dominated by capillarity that allowed the use of a simple formula to obtain the sorptivity from the steady-state flow rate that occurred very early after the start of imbibition. The results of measurements of sorptivity made on a fine sand agreed with those obtained from measurements on one-dimensional water infiltration into columns of the sand. Sorptivity measurements on stabilized aggregates of a clay soil and on air-dried field aggregates of a clay soil were easily made. The simplicity and rapidity of the method allowed measurements to be conveniently replicated. 相似文献
125.
Ovariectomized, nonlactating cows were treated with IM injections of either physiologic saline solution or prostaglandin F2 alpha. Plasma concentrations of cortisol increased significantly by 30 to 60 minutes after injection of prostaglandin F2 alpha, but there were no significant increases in plasma concentrations of estradiol, progesterone, or testosterone. After saline solution treatment, there were no increases in any of the hormones measured. 相似文献
126.
127.
Nephrogenic diabetes insipidus is characterized by polyuria, hyposthenuria and compensatory polydipsia. With conventional clinical and laboratory examinations the diagnosis can be established and the differential diagnostic diseases excluded. In order to verify the diagnosis, differentiate the condition from central and nephrogenic diabetes insipidus and rule out psychogenic polydipsia, additional laboratory studies are required: of these, the concentration test, modified Carter-Robbins test and AVP stimulation test are described. 相似文献
128.
Karen R. Muñana Patricia J. Luttgen Mary Anna Thrall Thomas W. Mitchell David A. Wenger 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(2):117-121
Seven Domestic shorthair cats with a lysosomal storage disorder analogous to human Niemann-Pick disease type C, from a breeding colony were studied to characterize the neurological manifestations of this disorder. Affected cats were identified by means of liver biopsies at 4 to 6 weeks of age. Neurological examinations were performed at 2 week intervals from the onset of clinical signs. All cats displayed signs referrable to the cerebellum, with a subtle intention tremor noticed initially at 8 to 12 weeks of age; the disease was rapidly progressive. The tremor became more pronounced, menace response was lost, and severe dysmetria and ataxia developed. Three cats also had signs referrable to other areas of the central nervous system. Cats died or were euthanized between 12 and 43 weeks of age. Pathological findings included accumulation of substrate within neurons throughout the central nervous system, and axonal spheroid formation. The clinical and pathological findings in these cats are comparable to those in the human form of the disease. 相似文献
129.
T M Byrem T F Robinson Y R Boisclair A W Bell W S Schwark D H Beermann 《Journal of animal science》1992,70(12):3812-3819
Pharmacokinetic parameters for the beta 2-adrenergic agonist, cimaterol (CIM), were determined in growing Holstein steers. Compartmental analysis was used after measurement of CIM in body fluids by affinity chromatography and HPLC using UV detection. Recoveries from spiked plasma and urine standards were 70 +/- 1.2% and 68 +/- 1.1%, respectively. The minimum detection level in plasma was 1 ng/mL and the average CV was 5.1% for concentrations that ranged from 1 to 30 ng/mL. Four steers (276 +/- 24 kg) received 15 mg of CIM by bolus intravenous injection. Plasma CIM levels declined in a biphasic manner with half-lives of 2.5 min for the distribution phase and 54 min for the elimination phase. A two-compartment open model was used to describe the disappearance of CIM and the following pharmacokinetic parameters were obtained: central compartment volume (Vc) = .76 L/kg, apparent volume of distribution (Vd) = 4.1 L/kg, and transfer rate constants from the central to peripheral compartment (k12) = .177/min, from the peripheral to central compartment (k21) = .054/min and elimination from the central compartment (kel) = .074/min. After 8 h, total urinary CIM accounted for only 18.3% of the administered dose. Results suggest that circulating concentrations of CIM in growing steers are influenced by its accumulation in an unidentified peripheral pool and its conversion into unknown metabolite(s) before elimination. 相似文献
130.
选用6只9周龄新西兰母兔,评定环境温度和饲粮营养浓度对生长期母兔代谢能利用率的影响。试验在密闭式的小动物呼吸测热柜中进行。分别对处于环境温度为20±2℃和30±2℃,采食两种不同营养浓度的试兔进行测试。饲粮营养水平实测值,分别为12.22kJ ME/g和13.49kJ ME/g;粗蛋白质(CP)分别为17.3%和21.6%;中性洗涤纤维(NDF)分别为23.7%和16.5%。结果表明:环境温度影响试兔的能量平衡,它与采食量间存在着显著的相关。20±2℃时,相关系数r=0.798;30±2℃时,相关系数r=0.875。在本试验设计范围内,饲粮营养浓度并不影响代谢能食入量(ME_I),热增耗(HP)和能量平衡(EB)。当环境温度为20±2℃和30±2℃时,表观代谢能转化率(NE/ME)分别为51%和71%;每天每兔每千克代谢体重代谢能维持需要分别为396 kJ和361 kJ。试验结果认为:环境温度影响营养物质消化率(P相似文献