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1

Genetic evaluation of litter size traits in Pannon Large rabbits

100%
Nguyen N. T., Farkas J., Szendro Z., Nagy I.
Animal Science Papers and Reports
|
2017
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tom 35
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nr 2
Genetic parameters and genetic trends for the number of kits born alive (NBA), number of kits born dead (NBD) and the total number of born kits were estimated in Pannon Large rabbits. Using the REML method 12 single trait models were examined. Heritability estimates were low for all traits and ranged between 0.07-0.08 (with standard errors 0.018-0.021) for NBA (5830 records), 0.01-0.02 (0.009-0.009) for NBD (6278 records) and 0.04-0.05 (0.015-0.018) for TNB (6278 records) from 1469 does. The ratios of the permanent environmental and the phenotypic variances exceeded of the heritability estimates and ranged between 0.11-0.16(0.016-0.018) for NBA, 0.06-0.07 (0.014-0.015) for NBD and 0.11-0.17 (0.014-0.017) for TNB. When characterizing the goodness of models bias values were practically zero for all traits and models. After identifying the best fitted model (containing parity, age of the doe and year-month of kindling effects) it was extended with dominance effects. As a result, heritability estimates decreased to 0.06 (0.028) for NBA, 0.02 (0.012) for NBD and 0.02 (0.022) for TNB. The relative importance of the permanent environmental effects also decreased to 0.09 (0.031) for NBA, 0.05 (0.024) for NBD and 0.07 (0.028) for TNB. Ratios of the dominance effects exceeded those of the heritability estimates and amounted to 0.27 (0.024) for NBA, 0.05 (0.013) for NBD and 0.38 (0.025) for TNB. When compared to the additive model, the model including dominance showed some confounding with additive genetic and with permanent environmental effects and reduced calculated genetics trends (0.035 vs 0.03, -0.0017 vs -0.003 and 0.016 vs 0.01 for NBA, NBD and TNB, respectively). Spearman rank correlation coefficients between breeding values of the additive and dominance models were high for all traits (0.96-0.98). When dominance effects were included some re-ranking was observed among the top ranked animals for every trait.
2

Grading standards and their effect on estimates of variance components and genetic trends in the silver fox [Vulpes vulpes L.]

100%
Wierzbicki H., Filistowicz A.
Journal of Animal and Feed Sciences
|
2003
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tom 12
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nr 1
3

Evaluation of pastel fox breeding results in Poland - reproduction

84%
Jakubczak A.
Electronic Journal of Polish Agricultural Universities. Series Animal Husbandry
|
2002
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tom 05
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nr 2
The evaluation of pastel fox breeding results was carried out through the estimation of selection differentials and genetic and phenotypic trends in some performance traits. The observations covered common fox females, reared during 1978-1997, from which a total of 4155 offspring were obtained with pastel colour of coat. The analysis of reproduction indices demonstrated that the average percentage of whelping females oscillated around 65.63%. The average number of born offspring ranged between 2.56 and 4.42 per a female of the herd.
4

Evaluation of breeding activities of a mink farm

84%
Rozempolska-Rucinska I., Jezewska G., Zieba G.
Electronic Journal of Polish Agricultural Universities. Series Animal Husbandry
|
2004
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tom 07
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nr 2
Selection, one of the more important stages in fur animal breeding, is based on the phenotype of the animals only. Although a phenotype-based evaluation is the quickest and the simplest method that can be carried out in an on-farm environment, the results of such an evaluation, however, remain reliable exclusively in relation to highly heritable traits. The material comprised data collected from the breeding documentation of a standard mink reproduction farm and referred to 12 generations of animals. The covariance components of reproduction and conformation traits were estimated by means of the REML method based on a multitrait animal model, using the DMU software package. The components were used for a BLUP-based estimation of the breeding value of the animals. The genetic trends considerably differed from the phenotypic ones.
5

Inbreeding rate and its effect on three body conformation traits in Arab mares

84%
Sierszchulski J., Helak M., Wolc A., Szwaczkowski T., Schlote W.
Animal Science Papers and Reports
|
2005
|
tom 23
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nr 1
In a group of purebred Arab mares the level of inbreeding and its effect on three body conformation traits was determined. Moreover, estimated were heritability coefficients of the traits and their phenotypic,genetic and environmental trends. Considered were conformation records of 706 Arab mares born in the years 1936- 1993. The mean inbreeding level of mares was 0.88%. No considerable effect of inbred rate on body conformation traits was found. The obtained partial regression coefficients were close to zero. Heritability coefficients appeared low and amounted to 0.160 (±0.078) for height at withers, 0.052 (±0.067) for chest circumference and 0.050 (±0.054) for circumference of cannon.Negligible positive genetic trend was observed for all the traits studied, whereas the environmental trends were not clear.
6

Bayesian estimates of genetic variance of fertility and hatchability under a threshold animal model

84%
Dobek A., Szydlowski M., Szwaczkowski T., Skotarczak E., Molinski K.
Journal of Animal and Feed Sciences
|
2003
|
tom 12
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nr 2
7
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Genetic, phenotypic and environmental trends of conformation traits in arctic fox Alopex lagopus [L.]

84%
Wierzbicki H., Filistowicz A., Przysiecki P.
Journal of Applied Genetics
|
2000
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tom 41
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nr 2
8
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Genetic aspects of racing performance in Polish pure bred Arab horses. II. Genetic trends

84%
Sobczynska M., Kownacki M.
Journal of Applied Genetics
|
1997
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tom 38
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nr 3
The objective of this study was to estimate genetic trends in the Polish Arab horses population. Annual earnings and rank at finish in fiat races of Polish Arab horses from 1951 to 1993 were analysed with a BLUP animal model. The collected data included 2,234 records of 1,640 4- and 5-year old horses from 143 sires. Only races, in which horses of at least two mentioned age groups took part, were taken into consideration. The model included an individual additive genetic effect as random, the year of race, herd, sex, age, number of starts and the year of race X age effects as fixed effects. Genetic trends were estimated from differences between horses belonging to different age groups and racing in the same year. The annual genetic gains from 1951 to 1993 were 3.5% and 12.3% of the genetic standard deviation for the log of earnings and rank at finish, respectively. Although the main role in breeding Arab horses is played by beauty and exterior, small genetic progress in the log of earnings and rank at finish was obtained.
9

Genetic evaluation of production and reproduction traits in two selected lines of geese under multitrait animal model

84%
Wolc A., Barczak E., Wezyk S., Badowski J., Bielinska H., Szwaczkowski T.
Animal Science Papers and Reports
|
2008
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tom 26
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nr 1
Heritability of and genetic correlations among production and reproduction traits as well as genetic trends over eight years of selection were estimated in W11 (maternal) and W33 (paternal) lines of geese. Considered was body weight on week 8 (BW8) and week 11 (BW11), number of eggs produced (EP), egg weight (EW), percentage of fertility (PFE), and percentage of hatchability from eggs fertilized (PHC). Multitrait animal model was applied. Moderate to high heritability estimates were obtained for BW8, BW11 and EP in both lines while lower for PFE and PHC. Highest genetic correlations were estimated between PFE and PHC and between the body weight traits. No clear genetic trends for any trait were identified. Generally, unfavourable relationships between productive and reproductive traits have been confirmed.
10

The genetic background of longevity in David's deer [Elaphurus davidianus, Milne Edwards 1866]

84%
Sternicki T., Wolc A., Szwaczkowski T.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
|
2005
|
tom 72
11

Analysis of effectiveness of breeding work and estimation of genetic and phenotypic trends of conformation traits in selected varieties of coloured American mink

67%
Kolodziejczyk D., Socha S.
Electronic Journal of Polish Agricultural Universities. Series Animal Husbandry
|
2012
|
tom 15
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nr 3
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Genetic and production trends in New Hampshire laying hens over 8 generations

67%
Calik J.
Acta Scientiarum Polonorum. Zootechnica
|
2011
|
tom 10
|
nr 3
The aim of the study was to determine trends for genetic and production parameters in a population of New Hampshire N-11 laying hens over 8 generations. Individual performance testing included body weight at 33 weeks of age (g), egg weight at 30 weeks of age (g), age at puberty expressed as days of age at first egg (days), and number of eggs laid to 39 weeks of age. As a result of implementing the genetic improvement programme based on NOVASEL electronic data processing system, egg production was increased, age at first egg was advanced and body weight of the chickens decreased in the N-11 line. The analysis of estimates of effective population size (Ne) and coefficients of inbreeding (Fx) shows that the cockerel and hen mating system used for reproduction effectively protects the population from an increase in inbreeding.
13

Genetic trends of laying merit in maternal [M55] and paternal [V44] strains of hens

67%
Zieba G., Lukaszewicz M., Twardowska M., Witkowski A.
Animal Science Papers and Reports
|
2003
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tom 21
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nr 4
The purpose of the study was to evaluate with BLUP the effectiveness of breeding work performed in a commercial farm of laying hens where the selection index approach was applied. Production results of two (maternal M55 and paternal V44) nucleus strains regarded nine generations (1994-2002). Considered were body weight at the age of 18 weeks (BW), age (days) at first egg (MAT), number of eggs laid during first 15 weeks (IL), mean egg weight at week 10 of laying (EW), number of eggs laid during 44 weeks (L44) and hatchability (HA). Mean inbreeding coefficient of inbred birds amounted to 1.7 and 2.2%, in M55 and V44, respectively. Estimates of h2 (REML with animal model) were found similar in both strains, being highest for BW (0.604 and 0.646) and EW (0.536 and 0.607) and lowest for IL (0.180 and 0.185 in M55 and V44, respectively). Annual genetic changes (BLUP) were:0.69 and 0.54 eggs for IL, 2.64 and 2.23 eggs for L44, -0.62 and -0.79 days for MAT, –0.09 and 0.16 g for EW, respectively for M55 and A44 strains.
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