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从5000余只杂种兔中,按公母比例1∶8选择300余只体重大、产毛量高的个体进行横交固定,经过4个世代的选育,兔只(11月龄)平均体重达5386克,年产毛量1424克,粗毛率11.74%,结块率2.24%,胎产活仔7.26只,料毛比43∶1。种兔外貌特征一致,遗传性能稳定。现有核心群种兔1200只,繁殖群7200只,生产群2.5万余只,向省内外推广繁育28万只,各项生产指标均达到或超过预定标准及全国家兔育种委员会制定的“德系长毛兔种兔鉴定标准”和“粗毛型长毛兔的选育指标”。 相似文献
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Echocardiographic Estimates of Right Ventricular Systolic Function in Dogs with Myxomatous Mitral Valve Disease 下载免费PDF全文
E.H. Chapel B.A. Scansen K.E. Schober J.D. Bonagura 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):64-71
Background
Right ventricular (RV) dysfunction independently predicts outcomes in human myxomatous mitral valve disease (MMVD). There is limited information regarding RV systolic function in dogs with MMVD.Hypothesis
Right ventricular systolic function differs among stages of disease, decreasing in decompensated MMVD.Animals
Thirty‐sixclient‐owned dogs with MMVD not receiving oral cardiovascular medications.Methods
Prospective clinical study. Dogs were categorized according to disease severity as ACVIM Stage B1, B2, or C. Seven echocardiographic indices of RV systolic function were measured. Groups were compared by 1‐way ANOVA and Tukey's HSD test. Frequencies of cases with cardiac remodeling falling outside previously established reference intervals were compared using Fisher's exact test. Intra‐ and interobserver measurement variability was calculated for each RV function index.Results
The indices TAPSE (P = 0.029), RV StL (P = 0.012), and RV StRL (P = 0.041) were significantly different between groups. A greater proportion of B2 dogs (7 of 12) had TAPSE values above reference intervals compared with B1 (2 of 12) or C (2 of 12) dogs (P = 0.027). Measurement variability of TAPSE, RV S', and RV StG was clinically acceptable.Conclusions and Clinical Importance
Right ventricular systolic function differs between stages of MMVD, increasing in stage B2, and declining in stage C. The prognostic importance of RV function indices, particularly TAPSE, might be worth evaluating in dogs with MMVD. 相似文献15.
Wambura PN 《Tropical animal health and production》2009,41(2):149-152
The efficacy of green-coloured (GC) I-2 Newcastle disease vaccine was determined in the present study. I-2 vaccine was mixed
with a green coloured dye and stored at 4°C for 6 months while assayed for the virus infectivity at a monthly interval. Chickens
were vaccinated with the GC vaccine by eye drop. Serum samples were collected from all birds before and after vaccination
at weekly interval for 4 weeks and tested for haemagglutination-inhibition (HI) antibody against Newcastle disease virus (NDV). These chickens were challenged with NDV virulent strain four weeks after vaccination. The results showed that there
was no difference between the infectivity titres of GC and uncoloured vaccines. However, chickens vaccinated with GC vaccine
produced higher HI antibody titres than chickens vaccinated with uncoloured vaccine. Results from the challenge trial showed
that all vaccinated chickens survived whereas all unvaccinated chickens died. The findings from this study have shown that
the GC vaccine is safe and produced protective antibodies against NDV in vaccinated chickens.
Wambura, P. N., 2008. Protective antibody response produced by the chickens vaccinated with green coloured thermostable Newcastle
disease virus. Tropical Animal Health and Production. 相似文献
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烟草赤星病不同菌株致病力差异的研究 总被引:1,自引:0,他引:1
本试验研究结果表明:采用离体叶片鉴定品种抗病性时点滴法优于喷雾法.从来源不同的11个烟草赤星病菌株中筛选出致病力最强的A4菌株,鉴别出几个烟草品种抗病性由强到弱的顺位为净叶黄>晒烟9号>风林一号>G80>Nc89>K326.提出了烟草赤星病菌存在生理小种的可能性 相似文献
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为获得可用于鸡传染性法氏囊病病毒(IBDV)抗体检测的重组抗原VP2蛋白,根据GenBank中发表的IBDV VP2序列设计一对特异性引物,应用RT-PCR技术克隆IBDV经典标准攻毒株(BC6/85株)的VP2基因,插入质粒pET-32a中构建重组表达质粒pET-32a-VP2,经IPTG诱导后获得了以包涵体形式表达的重组蛋白。重组蛋白纯化后,Western-blot检测表明具有良好的反应原性。本研究为下步建立IBDV抗体的间接ELISA方法及新型疫苗的研制奠定了基础。 相似文献
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《Veterinary microbiology》2015,175(1):105-113
Bacterial infections causing mastitis in sheep can result in severe economic losses for farmers. A large survey of milk samples from ewes with mastitis in Sardinia, Italy, indicated an increasing prevalence of Pseudomonas aeruginosa infections. It has been shown previously that during chronic, biofilm-associated infections P. aeruginosa populations diversify. We report the phenotypic and genomic characterisation of two clonal P. aeruginosa isolates (PSE305 and PSE306) from a mastitis infection outbreak, representing distinct colony morphology variants. In addition to pigment production, PSE305 and PSE306 differed in phenotypic characteristics including biofilm formation, utilisation of various carbon and nitrogen sources, twitching motility. We found higher levels of expression of genes associated with biofilm formation (pelB) and twitching motility (flgD) in PSE305, compared to the biofilm and twitching-defective PSE306. Comparative genomics analysis revealed single nucleotide polymorphisms (SNPs) and minor insertion/deletion variations between PSE305 and PSE306, including a SNP mutation in the pilP gene of PSE306. By introducing a wild-type pilP gene we were able to partially complement the defective twitching motility of PSE306. There were also three larger regions of difference between the two genomes, indicating genomic instability. Hence, we have demonstrated that P. aeruginosa population divergence can occur during an outbreak of mastitis, leading to significant variations in phenotype and genotype, and resembling the behaviour of P. aeruginosa during chronic biofilm-associated infections. 相似文献
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IntroductionFew studies have evaluated the utility of echocardiographic indices of right ventricular (RV) function in predicting prognosis in dogs with myxomatous mitral valve disease (MMVD).AnimalsSixty-seven client-owned dogs were diagnosed with MMVD.Materials and methodsclinical cohort study. Dogs diagnosed with American college of veterinary internal medicine (ACVIM) stage B2, C or D between April 2014 and March 2017 were enrolled. Long-term outcomes were assessed by telephone or from the medical record. The primary end-point was defined as cardiac-related death. Echocardiographic indices of RV function, including the RV Tei index, free wall and septal RV longitudinal strain, were obtained. Univariable and multivariable Cox proportional hazard analyses were used to identify variables predictive of cardiac-related death.ResultsTwenty-four dogs died during the follow-up period. The median follow-up time was 482 days, and the median survival time for dogs with cardiac-related death was 230 days. For cardiac-related death, peak early diastolic mitral inflow velocity, ACVIM stage C or D, tricuspid regurgitation velocity, RV Tei index and RV end-diastolic area were predictors in univariable Cox proportional hazard analysis. In multivariable Cox proportional analysis adjusted for the left atrial to aorta ratio, peak early diastolic mitral inflow velocity and ACVIM stage, an increase in the Tei index by 0.1 increased the hazard ratio of cardiac-related death by 33% (95% confidence interval, 16–70%; P = 0.002).ConclusionsIn dogs with MMVD, RV dysfunction assessed by the Tei index is an independent predictor of cardiac-related death. 相似文献