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Study of a Turkey Population for Gene Preservation
48-52Views:85Genetic variability is very important in small populations. We examined an indigenous bronze turkey population which is bred for gene conservation in order to see if the current mating system maintains genetic variability. The present generation was surveyed using microsatellite markers and a computer model was used to simulate changes in the population over 100 generations.
The data was analysed using the concept of entrophy from information theory instead of genetic variance so that we could more accurately measure genetic variability.
The results indicate that the breeding method currently in use, rotational line mating, is acceptable with respect to preserving genetic variability, but new selection methods may provide additional protection against the loss of alleles. -
Statistical comparison of coverage data of disturbed habitats in the Hajdúság
171-178Views:73Between 2002 and 2006 we made the coenological survey of five disturbed habitats marked as grasslands. With our coenological examinations and the statistical analyses we wanted to make the detailed botanical survey of the given five habitats in order to verify that the maintenance of habitats amongst agricultural lands – and considered as less valuable – is of high importance and necessary from an environmental point of view, since these habitats are often living and feeding areas of many rare and/or protected plant- and animal species.
As a result of the statistical analyses we have pointed out that number of species in case of all the five habitats extreme fluctuation characterizes the statistical universe. As regards the
average of the coverage it is the highest in case of the third habitat (degraded Puccinellia grassland), and the coefficient of variation shows homogenity as well. In examining the Shannon-value the average is the highest in case of the second habitat (Alopecurus meadow), and the statistical dispersion is the smallest. The coefficient of variation shows medium variability. The median of evenness is the lower in case of the third habitat (degraded
Puccinellia meadow) and the statistical is the highest here as well.
We have done the Hierarchical and the K-Means Cluster Analyses for the 21 plant associations of the five habitats. Both cluster analyses put the same associations into the same cluster, so
one can state that the associations in each cluster are different from the associations of the other ones according to the coverage data of the plant families. -
Analysis of the Grey Colour Intensity in Horses
3-7Views:101An investigation of different grey coat colours and a connection between colour and age of horses was carried out with two Hungarian State Studs: Bábolna and Szilvásvárad. For objective measurement of coat colour Minolta Chromameter (Model CR-210) was used. The average value of L (lightness) level by Shagya and Pure Bred Arabian horses was 63.83 ± 2.23, for Lipizzan horses was x=71.00 ± 2.29 respectively. In each stud older horses (over 10 years of age) have a flea-bitten colour stage, which decreased the L value considerably. Changes in coat colour in connection with the greying process did not show an evident tendency in the three breeds.
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An Analysis of Rotational Line Mating Using Computer Simulation
35-39Views:112In a simulation examination, we analyzed the effect of the family size and the rate of pairing on the survival of rare genes, to keep the level of variation of the genepool and to avoid the loss of alleles.
The population size was 360 animals. In the simulation, we calculated on the basis of a discrete population. We placed the 360 animals into different clusters, with 3 types of frequencies of alleles and 3 types of groups. We assumed 2, 3 or 4 alleles in 8 loci. We generated 15 generations using the same mating and selection system used in practise. The simulation was written with Scilab 2.7.2 software, and evaluated with SPSS software.
There were significant changes in the effect of family size on the genetic variation in the following cases: when the base population had the same gene frequencies in all loci, and when the gene frequencies were between 0.125-0.75. In these cases, we found that the smaller families (10 animals/cluster) were better than the larger families (30 or 90 animals/cluster). The first generation where there accured a loss of alleles was averagely earliest in larger families (90 animal/cluster). This average was 3.37 generations. When we are searched the effects of the different rates of pairing we found those cases most favourable when the ratio of males and females was 1:2 or 1:4 as compared to 1:9. The first generation where there was a loss of alleles was averagely earliest at the ratio of pairing male and females of 1:9 (the mean was 3.05 generations) when the frequency of the rarest allele was 0.0069.
The recently introduced rotating-random mating system is an eligible method for small populations for the preservation of genes. -
Simulation Experiments for Observation of Different Genetic Parameters
46-49Views:81The change of genetics variance in various simulated population were examined trough 25 generations. The population size were 1000, 2000, 4000, 8000 and 16000. The number of genes were1, 2, 3, 4 and 5. Two allels per gene were applied. It was assumed that base population was randomly mated. Also it was assumed that a pair of allel genes was independent, there was no epistasis, linkage between alleles of different loci, dominance and overlapping generations. In the selection was kept the 93% of females and 0.186% of males. The size of populations was close to constant through generations.
The size of populations and the number of loci were effects that how many generation is necessary to get genetical maximum. The change of the genetical mean of the population and the genetical variance were well subscribed cube and logistical curve. We can use to estimate these genetical parameters with the previous functons.