Genotype × environment interaction as it relates to egg production in turkeys (Meleagris gallopavo)

Three different unrelated natural populations of Drosophila melanogaster from Scotland, Japan and Egypt, as well a highly inbred line, were the basis of the present study. Crosses were made within and between natural populations and between each of the natural populations and the highly inbred line to obtain the parental, F1 and F2 generations and their relative fitness studied at 15°, 25° and 28 °C.The F1 interpopulation hybrids were superior to both parents in egg production, percentage emergence and longevity of adults in most of the crosses. Heterosis tended to be higher at 15° and 28° than at 25 °C. The F2 in all crosses was inferior to the F1 and also inferior to one or both parents. In crossing the inbred line with any of the natural populations, the F1 generally showed higher heterosis than that of the interpopulation hybrids; the F2 was also inferior to the F1 but superior to the inbred parent.Significant genotype-environment interaction was detected, indicating the differences in sensitivity to temperature in each population. Variance of any-given fitness character of a superior population at a given temperature was often smaller than the poor genotype. There was a decline in the coefficient of variation in the F1 generation and an increase in the F2's.

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The effect of different levels of management on the assessment of differences within a variety of chicken

Animal Science ◽

10.1017/s0003356100038344 ◽

1967 ◽

Vol 9 (1) ◽

pp. 121-125 ◽

Cited By ~ 1

Author(s):

M. W. Oakes

Keyword(s):

Egg Production ◽

Genetic Correlations ◽

Environment Interaction ◽

Components Of Variance ◽

Genotype Environment Interaction ◽

Single Location ◽

Body Weights ◽

The Mean ◽

Maximum Expression ◽

Different Levels

The data relating to twenty single location trials, involving the progeny of seven sires from one variety mated with random females from another, have been analysed to obtain estimates of sire × location (genotype–environment) interaction for egg production, 23- and 64-week body weights and 32-and 45-week egg weights. In no case was a significant interaction found, indicating genetic correlations not significantly different from unity.The between- and within-sire components of variance have been calculated for each trait on each location separately. The regressions of these components on the mean levels at the locations have been obtained. Though low and non-significant, they tend to support the use of those locations giving maximum expression of a trait for comparisons involving that trait.

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A comparison of the interaction, with two types of environment, of pure strains or strain crosses of poultry

Genetics Research ◽

10.1017/s0016672300003761 ◽

1963 ◽

Vol 4 (3) ◽

pp. 370-381 ◽

Cited By ~ 11

Author(s):

P. Hull ◽

R. S. Gowe ◽

S. B. Slen ◽

R. D. Crawford

Keyword(s):

Body Weight ◽

Sexual Maturity ◽

Environmental Effect ◽

Egg Production ◽

Genetic Variance ◽

Environment Interaction ◽

Reciprocal Crosses ◽

Genotype Environment Interaction ◽

Six Traits ◽

Interaction Variance

In these experiments comparisons were made between the magnitude of the interaction of ‘pure’ strains and strain crosses of poultry with two types of environments—location effects and a restricted-feed versus a full-feed rearing programme. The ‘pure’ strains were closed flocks of White Leghorns that had been selected for increased egg production, while the strain crosses were the reciprocal crosses of all combinations of these pure strains. Data from four separate experiments in four consecutive years used for this study involved 8320 laying birds. Six traits of the adult laying birds were used for these analyses.It was expected that the ‘pure’ strains would differ in performance amongst themselves to a greater extent than the strain crosses, and for the two traits, body-weight at housing and sexual maturity, this was found to be the case in three out of four years. These two traits were affected to the greatest extent by the rearing treatment. Also, the genotype-environment interaction variance was found to be significant and of important magnitude relative to the genetic variance for these two traits. Where the environmental effect was found to be smaller, the interaction variance made up a smaller proportion of the genetic variance.

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