Georg Henner  Fabricius und F. Kollmann 《Forstwissenschaftliches Centralblatt》1940,62(2):46-48

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Georg Henner  M. und Rubner 《Forstwissenschaftliches Centralblatt》1926,48(9):665-672

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Acknowledgement to referees     

Georg Erhardt  Franz Pirchner  Lawrence R. Schaeffer  Henner Simianer  Gerald Stranzinger 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2003,120(1):68-72

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Genetic analysis of racing performance in Irish greyhounds     

H. Täubert  D. Agena  & H. Simianer 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(3):117-123

The aim of this study was to analyse racing performance data in Irish greyhounds with regard to genetic and environmental variation. Estimation of heritabilities for racing time (RT) and ranking, and the prediction of breeding values for all greyhounds in the investigated data were carried out. Data from 42,785 races in Ireland in the years 2000-2003 were available. These results were obtained from 42,880 greyhounds on 20 race tracks over a distance of 480 m. Three traits were analysed, RT, ranking and a scaled logarithmic function for RT (ART), which was used to adjust racing time to be normally distributed. The data were analysed with a bivariate animal model. The estimated heritabilities were moderate for RT (0.31) and ART (0.38), but very low for ranking (0.10). The repeatabilities were 0.56 (RT), 0.51 (ART) and 0.13 (ranking). The genetic correlations were very high, 0.99 (RT-ranking) and 0.96 (ART-ranking), while the phenotypic correlation was lower, 0.60 (RT-ranking) and 0.62 (ART-ranking). The genetic trend for the traits as well as the phenotypic change of the average RT was positive.  相似文献   

Approaches to the management of inbreeding and relationship in the German Holstein dairy cattle population     

S. Koenig  H. Simianer 《Livestock Science》2006,103(1-2):40-53

The aim of this study was to estimate the current level of inbreeding in the German cow population and for bull dams born in Germany, to find out sires most related to different subsets of their breed and to demonstrate the negative effect of homozygosity in the case of complex vertebral malformation (CVM). Further on, the application of optimum genetic contribution (OGC) theory for the selection of bull dams and bull sires in different breeding scenarios was investigated. Levels of inbreeding for the cow population were in a low range from 0.97% to 1.70% evaluating birth years from 1996 to 1999 in a total dataset of 244,427 registered Holstein cows. The inbreeding coefficient of 8030 bull dams was much higher, i.e. 3.71%, for the birth year 1999. Increases in inbreeding of 0.19% per year indicated an effective population size of only 52 animals. Individual sires like R.O.R.A. Elevation and Hannoverhill Starbuck were highly related to potential bull dams with coefficients of relationship of 13.4% and 12.9%, respectively, whereas P.F. Arlinda Chief (16.3%) and Carlin-M Ivanhoe Bell (16.1%) were highest related to the best available AI sires. Coefficients of relationship were calculated by classes of estimated breeding values (EBV) for production traits showing highest values above 7% in the two highest EBV-classes. The optimum genetic contribution theory using official EBVs and approximative, for zero inbreeding corrected EBVs, was applied for elite matings in a breeding program embracing 30 young bulls per year to find the optimal allocations of bull sires and bull dams. Compared with the actual breeding program applied in practice, OGC-theory has the potential to increase genetic gain under the same constraint for the increase of average relationship by 13.1%. A more relaxed constraint on increase in inbreeding allowed even higher expected genetic gain whereas a more severe constraint resulted in more equal contributions of selected bull sires. Contributions from 21 selected bull sires and 30 selected bull dams for a scenario at 5% constrained relationship were used to develop a specific mating plan to minimise inbreeding in the short term in the following generation applying a simulated annealing algorithm. The expected coefficient of inbreeding of progeny was 66.3% less then the one resulting from random mating. Mating programs can address inbreeding concerns on the farm, at least in the short term, but long-term control of inbreeding in a dairy population requires consideration of relationships between young bulls entering AI progeny test programs. Significantly better EBVs of CVM-free bulls compared with CVM-carriers for the paternal fertility justify the application of OGC for elite matings.  相似文献   

Bücheranzeigen     

Dr. Georg Henner  M.  Rubner 《European Journal of Forest Research》1926,48(9):642-644

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Bücheranzeigen     

Y.  Dr. Georg Henner  Tubeuf  L.  Lukinger  Dr. F. Ernst  Wittich  Fabricius 《European Journal of Forest Research》1928,50(1):25-39

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Reihold  I. H. Flatfcher  Henner und Harrer 《Forstwissenschaftliches Centralblatt》1930,52(4):120-128

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Georg Henner  Tubeuf  Y.  Schüpfer und Fr. Moll 《Forstwissenschaftliches Centralblatt》1928,50(11):374-384

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Beiningen und Georg Henner 《Forstwissenschaftliches Centralblatt》1926,48(3):221-223

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