杉木无性系造林对比试验及重复力估测

引进浙江省12个杉木无性系扦插苗在Ⅱ、Ⅲ类立地的不同坡位上与福建省大田桃源国有林场初级种子园实生苗进行造林对比试验.结果表明,20 a生时12个无性系间在树高、胸径、冠幅、单株平均材积生长上均存在极显著差异,枝下高因造林密度原因差异不显著;不同坡位造林对无性系的影响,除冠幅显著外,其它各生长性状均极显著;与实生苗对比,适宜本地发展的杉木无性系首选57号、28号,其次为38号、A1、110号,可作为建立采穗圃的优良种源.无性系各生长性状重复力测算结果表明,20 a生时各无性系与原株之间的遗传特性保持极高的稳定性.     

Selection for resistance to Phytophthora pod rot of cocoa (Theobroma cacao L.) in Cameroon: Repeatability and reliability of screening tests and field observations

Phytophthora pod rot (Ppr) disease caused by Phytophthora megakarya is the major constraint to cocoa production in Cameroon. The development of resistant varieties requires the use of effective resistance testing methods. The repeatability and reliability of the leaf disc and detached pod tests, as applied in selection activities in Cameroon, were studied. Repeatability of the tests was estimated by calculating the correlation (r) between resistance scores of clones, progenies and individuals within progenies in different inoculations rounds of the leaf disc and detached pod tests. Such correlations were generally significant for both tests. For the leaf disc test, as expected, correlations were lower for individuals within seedling progenies than for the average of seedling progenies or of clones. This suggests that a higher number of replicate observations are required for correct evaluation of individual seedlings than for evaluation of the average level of resistance of progenies. Observations carried out 5 or 7 days after inoculation was highly correlated, suggesting that scoring in the leaf disc test may be done only once at 5, 6 or 7 days after inoculation. In one experiment the ranking of leaf disc and detached pod inoculation test results could be compared statistically, with data being significantly correlated (r 0.78). The reliability of the tests was evaluated by the correlations between results of the tests and the level of field infection. These were generally positive and significant, for the leaf disc and detached pod test. A variation between mean scores of 5 and 8 in the detached pod test appeared to be related to a 40% difference in field infection with P. megakarya in years with medium disease pressure. However, correlations with field resistance were not always significant, suggesting the influence of uncontrolled environmental factors affecting field observations or the results in the screening tests. It is concluded that the leaf disc and detached pod tests, if applied under standardized conditions, can be of great value to speed up selection for Ppr resistance.     

Evaluation of the Logan & Boyce plaque index for the study of dental plaque accumulation in dogs

The objectives of this study were to assess intra-examiner (experienced examiner) and inter-examiner agreements (experienced versus non-experienced examiners) of scores assessed with the Logan & Boyce plaque index and to evaluate whether a modification of this index, where anatomical landmarks are used for horizontal division [mod L&B-AL] and dye references are used for assessing intensity of dye (plaque thickness) [mod L&B-DR], would improve repeatability. The Logan & Boyce index was found to be inaccurate when scoring plaque coverage as it underestimated the total crown surface. The contribution of the gingival part to the total tooth score was minimized by the Logan & Boyce index compared to the mod L&B-AL/DR. Precision of global plaque scorings was significantly improved by the mod L&B-AL/DR. Intra-examiner agreement of plaque thickness and plaque coverage scorings on the gingival part of the tooth was significantly improved by the mod L&B-AL/DR. Studies evaluating plaque accumulation in dogs should therefore use the mod L&B-AL/DR rather than the Logan & Boyce index.     

Repeatability of a telephone questionnaire on cat-ownership patterns and pet-owner demographics evaluation in a community in Texas, USA

The repeatability of a telephone questionnaire on cat-ownership patterns, demographics and attitudes towards homeless cats in a community was evaluated. Randomly selected households (n = 100) within Caldwell, Texas, were included in the study. The response percentage was 84% (100/119) among those contacted and 75% (100/134) among all eligible respondents. Repeatability was measured by administering the same survey twice to the first 100 responding subjects, with an average (range) of 48 (25–64) days between interviews. The survey was initially administered from 6 June to 28 June 2005 and the follow-up survey was administered from 19 July to 11 August 2005. Repeatability for most cat-ownership characteristics was fair to good between the two interviews (kappa 0.47–0.82). Knowledge of companion animals and subject attachment to pet questions had good correlations between the two interviews (r_sp 0.52 and 0.60, respectively). Subject-demographic questions had excellent repeatability (kappa 0.66–1.00).     

Repeatability of equine health and management information obtained via a telephone questionnaire

The repeatability of equine health and management data obtained via a telephone survey of 60 horse owners and trainers was evaluated by using a test-retest method. One month following completion of the initial telephone questionnaire, the owners and trainers were asked to complete a retest questionnaire which contained a subset of 31 questions from the original survey. The second (retest) questionnaire collected information concerning the same time period as the first interview, i.e. the 4 week period prior to the original admission date of the horse. Measures of agreement were calculated using Spearman's rank correlation coefficient for continuous variables and the Kappa statistic for categorical variables.

Overall, measures of agreement were very favorable, ranging from good to excellent for nearly all questions examined. The results of this study indicate that repeatable information concerning equine health and management data can be obtained via a telephone interview and that a telephone questionnaire is a feasible method for obtaining information from horse owners and trainers.     

Evaluation of tricuspid annular plane systolic excursion measured by two-dimensional echocardiography in healthy dogs: repeatability,reference intervals,and comparison with M-mode assessment

Introduction

We sought to determine the feasibility, measurement variability, and within-day repeatability of tricuspid annular plane systolic excursion (TAPSE) measured by two-dimensional echocardiography (2D TAPSE), generate reference intervals for 2D TAPSE, assess agreement and correlation between 2D TAPSE and the conventional TAPSE measured by M-mode echocardiography (MM TAPSE), and to assess the ability of 2D TAPSE to track a drug-induced decrease in right ventricular (RV) function compared with MM TAPSE.