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排序方式: 共有453条查询结果,搜索用时 15 毫秒
41.
Avian polyomavirus (APV) and psittacine beak and feather disease virus (PBFDV) are the most common viral diseases of psittacine birds. In Taiwan, however, the existence of these viruses in psittacine birds has not been established. Polymerase chain reaction (PCR) methodology was therefore employed to ascertain whether APV and PBFDV genomes were present in isolates from psittacine birds of Taiwan. A total of 165 psittacine birds belonging to 22 genera were examined between 2002 and 2005. Findings revealed an APV-positive rate of 15.2%, a PBFDV-positive rate of 41.2%, and an APV/PBFDV dual infection rate of 10.3%. After cloning and sequencing, sequences of the PCR products were compared with sequences obtained from GenBank. For APV, the nucleotide identity among VP1 and t/T antigen coding regions ranged from 97.5% to 100% and 97.6% to 100%, respectively. For PBFDV, the nucleotide identity of ORF V1 and ORF C1 sequences ranged from 92.2% to 100% and 83.3% to 100%, respectively. The derived amino acid sequence alignment for PBFDV ORF V1 fragments revealed the conservation of two replication motifs and of the nucleotide binding site motif. In PBFDV, six of 42 deduced positions in the ORF C1 amino acid sequence were considered hypervariable. The established phylogenetic trees based on the four genome fragments examined in this study did not allow the assignment of particular APV or PBFDV nucleotide sequences to distinct avian species. 相似文献
42.
The purpose of this study was to detect differential expression of genes related to adipocyte differentiation in pigs by suppression subtractive hybridization. Adipocytes and stromal vascular cells (a fraction containing preadipocytes) from pig adipose tissue were isolated for mRNA extraction. The cDNA from preadipocytes was subtracted from the cDNA from adipocytes. The subtracted gene fragments were cloned into pGEM-T Easy TA cloning vector. We selected 384 clones for gene sequence determination and for further analysis. These genes were subjected to a differential screening procedure to confirm the differential expression of genes between the 2 cell types. We found that at least 36 genes were highly expressed in the adipocytes compared with preadipocytes. Among these, 6 genes including 2 novel genes with the greatest differences were selected and confirmed by Northern analysis. We found that angiotensin I-converting enzyme (ACE), ataxia-telangiectasia mutated protein (ATM), calpain 1, and stearoyl coenzyme A desaturase 1 (SCD1) were highly expressed in adipocytes compared with preadipocytes (P < 0.05). The relative mRNA abundance of ACE, ATM, calpain 1, SCD1, and 2 novel genes discovered in the current study was increased at the later stages of adipocyte differentiation (P < 0.05). The results confirmed that the genes involved in lipid metabolism and adipocyte differentiation were highly expressed in porcine adipocytes. However, further investigation is needed to demonstrate specific functions of the novel genes discovered in the current study. 相似文献
43.
Ko JC Payton ME White AG Galloway DS Inoue T 《Journal of the American Animal Hospital Association》2006,42(1):18-27
This crossover study tested the hypothesis that both diazepam and microdose medetomidine would comparably reduce the amount of propofol required to induce sedation. Four different medications, namely high-dose diazepam (0.4 mg/kg intravenously [IV]), low-dose diazepam (0.2 mg/kg IV), medetomidine (1 mug/kg IV), and placebo (0.5 mL physiological saline IV) were followed by propofol (8 mg/kg IV) titrated to a point where intubation could be performed. The effects of medetomidine were comparable to the effects of high-dose diazepam and significantly better than the effects of low-dose diazepam or placebo. Dogs in all treatment groups had transient hypoxemia, and induction and recovery qualities were similar. 相似文献
44.
RA Krimins JC Ko AB Weil ME Payton PD Constable 《American journal of veterinary research》2012,73(9):1363-1370
Objective-To evaluate hemodynamic effects in dogs after IM administration of dexmedetomidine (7.5 μg/kg, butorphanol (0.15 mg/kg), and tiletamine-zolazepam (3 mg/kg [DBTZ]) or dexmedetomidine (15 μg/kg), butorphanol (0.3 mg/kg), and ketamine (3 mg/kg [DBK]). Animals-5 healthy adult mixed-breed dogs. Procedures-Each dog received DBTZ and DBK in a randomized crossover study with a 48-hour interval between treatments. Anesthesia was induced and maintained with sevoflurane in 100% oxygen while instrumentation with Swan-Ganz and arterial catheters was performed. Following instrumentation, hemodynamic measurements were recorded at 3.54% (1.5 times the minimum alveolar concentration) sevoflurane; then sevoflurane administration was discontinued, and dogs were allowed to recover. Six hours after cessation of sevoflurane administration, baseline hemodynamic measurements were recorded, each dog was given an IM injection of DBTZ or DBK, and hemodynamic measurements were obtained at predetermined intervals for 70 minutes. Results-DBTZ and DBK induced hypoventilation (Paco(2), approx 60 to 70 mm Hg), respiratory acidosis (pH, approx 7.2), hypertension (mean arterial blood pressure, approx 115 to 174 mm Hg), increases in systemic vascular resistance, and reflex bradycardia. Cardiac output, oxygen delivery, and oxygen consumption following DBTZ or DBK administration were similar to those following sevoflurane administration to achieve a surgical plane of anesthesia. Blood l-lactate concentrations remained within the reference range at all times for all protocols. Conclusions and Clinical Relevance-In healthy dogs, both DBTZ and DBK maintained oxygen delivery and oxygen consumption to tissues and blood lactate concentrations within the reference range. However, ventilation should be carefully monitored and assisted when necessary to prevent hypoventilation. 相似文献
45.
Kim YH Kim ES Ko BS Oh SE Ryuk JA Chae SW Lee HW Choi GY Seo DW Lee MY 《Journal of animal science》2012,90(7):2075-2083
This study describes a method for discriminating Rangifer antlers from true Cervus antlers using agarose gel electrophoresis, capillary electrophoresis, quantitative real-time PCR, and allelic discrimination. Specific primers labeled with fluorescent tags were designed to amplify fragments from the mitochondrial D-loop genes for various Cervus subspecies and Rangifer tarandus differentially. A 466-bp fragment that was observed for both Cervus and Rangifer antlers served as a positive control, while a 270-bp fragment was specifically amplified only from Rangifer antlers. Allelic discrimination was used to differentiate between Cervus and Rangifer antlers, based on the amplification of specific alleles for both types of antlers. These PCR-based assays can be used for forensic and quantitative analyses of Cervus and Rangifer antlers in a single step, without having to obtain any sequence information. In addition, multiple PCR-based assays are more accurate and reproducible than a single assay for species-specific analysis and are especially useful in this study for the identification of original Cervus deer products from fraudulent Rangifer antlers. 相似文献
46.
47.
Antioxidant vitamins are commonly used as colorant, preventive, sweetener, nutritive and antioxidant materials in food industry. Thus, many studies have been conducted in recent years. We have performed the present study to understand the effects of α-lipoic acid (ALA), vitamin C and E, added into rations of Japanese quails, on chronic heat stress. This study was carried out in five groups as: control, stress, ALA, vitamin E and vitamin C groups. Heat stress is applied to all groups except the control group. Superficial pectoral muscles tissues were used for biochemical determinations. During the research, it is found that heat stress exerted undesired effects such as increasing lipid peroxidation (LPO) level indicating oxidative stress in Japanese quails. In addition, superoxide dismutase (SOD) and catalase (CAT) enzyme activities and glutathione (GSH) amounts were studied to understand the behaviour of defence mechanism. While stress increased LPO ratio, it was determined that all antioxidant added into the ration decreases LPO significantly (p < 0.05). In addition, it was determined that all of antioxidants added into ration effectively restored SOD activity and LPO ratio which heat stress affected negatively. Interestingly, vitamin C did not adjust GSH ratio in contrast to vitamin E and ALA, where vitamin E and C did not perform any positive effect on heat stress decreased CAT activity. Finally, it can be thought that antioxidant vitamins relatively ameliorated these undesired affects caused by stress factors given. 相似文献
48.
Biezyński J Skrzypczak P Piatek A Kościółek N Drozdzyńska M 《Polish journal of veterinary sciences》2012,15(2):285-290
Osteochondrosis is a common and clinically important joint disorder that occurs in human and many species of animals such as pigs, horses and dogs. The aim of this article is to present the results of conservative and surgical treatment of Osteochondrosis dissecans (OCD) and to compare the recovery time in relation to race, age and extent of cartilage damage. The study was performed on 36 dogs of both sexes, aged from 4 to 24 months, weighing 12-70 kg, of different breeds (predisposed and non-specific for this disease). All patients underwent clinical, orthopedic and radiological examination through which the location of OCD changes in the shoulder joint and the degree of this problem were established. Based on the examinations the patients were qualified for particular treatment procedures. Control tests were performed after 14, 30 and 60 days, which allowed for a precise evaluation of the progress of therapy. Achieved results indicate that dogs age and the lesions extent in the shoulder joint have an impact on the outcome of treatment. Studies showed that the best therapeutic effects were obtained in dogs aged 6-10 months, which underwent surgery. The study proved that the early diagnosis of OCD strongly influence the recovery rate and may inhibit the development of degenerative changes in the joint (DJD). 相似文献
49.
Sungjin Ko Jun-Gu Kang Jung-Yong Yeh Jin-San Moon Gui-Cheol Choi Sohyun Won Joon-Seok Chae 《Journal of Equine Veterinary Science》2013
The prevalence of equine respiratory virus infections among a suspected population of race horses was examined using polymerase chain reaction (PCR). One or more of five equine respiratory viruses were detected in the nasal swabs of 45 of 89 horses (50.6%), and the detection rate of equine herpesvirus type 1 (EHV-1), equine herpesvirus type 4 (EHV-4), equine herpesvirus type 5 (EHV-5), equine rhinitis A virus (ERAV) and equine rhinitis B virus (ERBV) were 5.6%, 7.9%, 39.0%, 2.2%, and 6.7%, respectively. Among the 45 infected horses, 7 were co-infected with EHV and/or equine rhinitisvirus (ERV). Equine influenzavirus and equine arteritisvirus were not detected in any samples. Specific antibodies to EHV-1 and/or EHV-4 were detected in 59 of 73 tested sera (80.8%), using a virus neutralization test. This investigation suggests that equine respiratory viruses are endemic at Seoul Race Park and that the impact of viral infections on race horses’ health in Republic of Korea should be evaluated. 相似文献
50.