The Correlated Response of Relative Aggressiveness to Selection for Body Weight and Breast Angle in Chickens

The correlated responses in egg quality traits to selection for high early body weight were studied in seven meat-type populations comprising five selected and two control lines. Traits studied were specific gravity, egg weight, albumen height, Haugh units, shell color, egg shape, shell roughness, wrinkling and asymmetry, and incidence of blood spots, meat spots and double yolks. Significant (P < 0.05 or < 0.01) correlated changes, as determined by the regression of correlated response (egg quality traits) on primary response (body weight), were obtained for egg weight, albumen height, Haugh units, asymmetry of shell and blood spots. All but blood spots increased with selection for high body weight. Shell color showed a consistent trend towards a darker color with increasing body weight. Scores for roughness of shell and, with one minor exception, the incidence of double yolks, also showed consistent trends (positive) with increasing body weight. Estimates of genetic correlations, derived directly from intra-line genetic analyses of the six pedigreed populations in the experiment, were in most cases in reasonable agreement with realized estimates.

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Effects of divergent selection for body weight on fibre number and diameter in two mouse muscles

Animal Science ◽

10.1017/s0003356100034814 ◽

1973 ◽

Vol 16 (1) ◽

pp. 7-16 ◽

Cited By ~ 22

Author(s):

J. P. Hanrahan ◽

A. C. Hooper ◽

J. C. McCarthy

Keyword(s):

Body Weight ◽

Fibre Diameter ◽

Correlated Response ◽

Weight Changes ◽

Body Weight Changes ◽

Muscle Weight ◽

Phenotypic Correlations ◽

Fibre Number ◽

Selection For ◽

Anterior Tibialis

SUMMARYThe effects of selection for increased or decreased body weight in mice, at 5 or 10 weeks of age, on the fibre number, fibre diameter and weight of the m. sternomastoideus and m. anterior tibialis muscles were studied. Unselected control mice were also included. Significant effects were detected in the case of each of the traits. However, the magnitude of any particular correlated response to selection varied between muscles and between selection ages in an unsystematic fashion. Most of the changes in muscle weight resulting from selection were attributable to positively correlated changes in fibre number but they were also accompanied by changes in fibre diameter in some cases.The correlated responses described indicate the difficulty of predicting how selection for body weight changes will influence cellular structure of any given muscle.Phenotypic correlations between muscle fibre number and diameter were essentially zero. The phenotypic correlations between muscle weight and fibre number and fibre diameter were positive.Sex had no effect on fibre number but had an effect on fibre diameter which depended on the particular muscle and the age of the animal.

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Ten generations of selection for predicted weight of testes in swine: direct response and correlated response in body weight, backfat, age at puberty, and ovulation rate

Journal of Animal Science ◽

10.2527/1994.7281978x ◽

1994 ◽

Vol 72 (8) ◽

pp. 1978-1988 ◽

Cited By ~ 28

Author(s):

Rodger K. Johnson ◽

Gregg R. Eckardt ◽

Thomas A. Rathje ◽

Denise K. Drudik

Keyword(s):

Body Weight ◽

Ovulation Rate ◽

Correlated Response ◽

Direct Response ◽

Selection For ◽

Age At Puberty

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Effect of selection for development rate on reproductive onset in female mice

Genetics Research ◽

10.1017/s001667239900381x ◽

1999 ◽

Vol 74 (1) ◽

pp. 55-64 ◽

Cited By ~ 4

Author(s):

C. A. ERNST ◽

P. D. CRENSHAW ◽

W. R. ATCHLEY

Keyword(s):

Growth Rate ◽

Body Weight ◽

Slow Growth ◽

Body Weight Gain ◽

Correlated Response ◽

Balance Growth ◽

Vaginal Opening ◽

Reproductive Onset ◽

Mature Weight ◽

Selection For

This research reports analyses of correlated response in reproductive onset in ICR mice after 23 generations of restricted index selection for divergent body weight gain, early (birth–10 days) or later (28–56 days) in life. Long-term selection altered growth trajectories and 56 day body weight of individuals under different selection regimes in this study. Mice in lines under early selection have the same percentage mature weight at vaginal opening as controls (63%). Vaginal opening is delayed in mice selected for slow early growth, which take longer to reach what appears to be a weight threshold. In contrast, individuals in lines selected for later slow growth undergo vaginal opening at the same age as controls, but at a lower weight and increased percentage mature weight. Pre-compensation or ‘counter-balance growth’ is observed in these lines, with mice selected for late enhanced growth reaching 52% of mature weight at vaginal opening while mice with late slow growth attain 71% of mature weight prior to vaginal opening. Only 42% of mice with late slow growth attain first oestrus by 56 days. We speculate this is a function of growth rate and fat/lean ratio. Mice with early slow growth show compensatory growth, reaching first oestrus at a similar time to controls. We conclude that selection for growth rate has asymmetrically affected reproductive onset, with lines selected for suppressed gains experiencing delays in the reproductive onset traits measured.

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Analysis of production records from a lowland sheep flock 3. Phenotypic and genetic parameters for reproductive performance

Animal Science ◽

10.1017/s000335610002256x ◽

1974 ◽

Vol 19 (1) ◽

pp. 33-45 ◽

Cited By ~ 18

Author(s):

P. A. Forrest ◽

Maurice Bichard

Keyword(s):

Body Weight ◽

Reproductive Performance ◽

Genetic Gain ◽

Genetic Parameters ◽

Phenotypic Correlation ◽

Correlated Response ◽

Sheep Flock ◽

Average Litter Size ◽

Genetic Level ◽

Selection For

SUMMARYPhenotypic and genetic parameters for reproductive performance in a flock of Clun Forest ewes have been estimated. Average litter size (ALS) appeared to be more repeatable than the number of lambs born per ewe mated and present at lambing (NLBEM), and the estimates obtained by regression (0·15 and 0·14) were slightly higher than those from the analyses of variance (0·12 and 0·09). The repeatability of barrenness was very low (0·05). It was concluded that little scope existed for the improvement of reproductive performance from a regular policy of culling.Estimates of heritability by analysis of variance and a method for all-or-none traits were 0·12 and 0·11 for ALS, and 0·15 and 0·10 for NLBEM, whereas barrenness was less heritable (0·07). An estimate of 016 was found for the heritability of ALS performance over two years. The phenotypic correlation between body weight and reproductive performance were positive yet small (ALS:+0·16; NLBEM:+0·10), while at the genetic level ALS was more strongly related to body weight (+0·21) than NLBEM (-0·04). The genetic regressions indicated that an increase of 5 lambs per 100 ewes lambing would accompany genetic gain of 5 kg in ewe body weight, while an increase of 1 lamb per ewe lambing would lead to a correlated response in body weight of 5 kg.Selection for ALS on the basis of dams' performance, within the flock studied, would be expected to yield a rate of progress of 2% per annum.

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GENETIC ANALYSIS OF BROWN ADIPOSE TISSUE, OBESITY AND GROWTH IN MICE

Genetics ◽

10.1093/genetics/106.4.705 ◽

1984 ◽

Vol 106 (4) ◽

pp. 705-718

Author(s):

A M Saxton ◽

E J Eisen

Keyword(s):

Body Weight ◽

Adipose Tissue ◽

Body Size ◽

Brown Adipose Tissue ◽

Genetic Parameters ◽

Control Diet ◽

Correlated Response ◽

High Fat ◽

Brown Adipose ◽

Selection For

ABSTRACT The hypothesis developed from single-gene mutant obese rodents that brown adipose tissue (BAT), through its thermogenic ability, is an important factor in the development of obesity, was tested in a randombred population of mice in which degree of adiposity is polygenically determined. Additive direct genetic parameters for measures of body size, lean, fatness and BAT at 6 wk of age were estimated under control and high-fat postweaning dietary regimens. Heritabilities were generally similar for the two diets. However, the lipid-free dry (LFD) component of BAT had a heritability estimate of 0.70 ± 0.26 on the control diet, but only 0.09 ± 0.20 on the high-fat diet. For all traits, genotype by diet interactions indicated that additive direct genetic rankings were not significantly different for the two diets. Based on estimates of genetic parameters in the control diet, selection for 6-wk body weight or 3- to 6-wk gain is expected to increase body size and adiposity. Selection for BAT weight is predicted to result in large, lean individuals. However, selection for the LFD content of BAT, generally believed to be a better indicator of thermogenic ability, is predicted to increase fatness as well as body size. Selection for LFD as a proportion of 6-wk body weight reduced the expected correlated response in fatness. It was concluded that BAT does not play a major role in determining the correlated response in obesity that is often found in populations selected for large body size.

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ESTIMASI NILAI HERITABILITAS BOBOT IKAN MAS VARIETAS PUNTEN DALAM PROGRAM SELEKSI INDIVIDU

Jurnal Riset Akuakultur ◽

10.15578/jra.11.3.2016.217-223 ◽

2016 ◽

Vol 11 (3) ◽

pp. 217

Author(s):

Estu Nugroho ◽

Budi Setyono ◽

Mochammad Su’eb ◽

Tri Heru Prihadi

Keyword(s):

Body Weight ◽

Selection Response ◽

Base Population ◽

Breeding Programs ◽

Male And Female ◽

Body Weight Trait ◽

Population Selection ◽

Selection For ◽

Weight Trait ◽

Selection Of

Program pemuliaan ikan mas varietas Punten dilakukan dengan seleksi individu terhadap karakter bobot ikan. Pembentukan populasi dasar untuk kegiatan seleksi dilakukan dengan memijahkan secara massal induk ikan mas yang terdiri atas 20 induk betina dan 21 induk jantan yang dikoleksi dari daerah Punten, Kepanjen (delapan betina dan enam jantan), Kediri (tujuh betina dan 12 jantan), Sragen (27 betina dan 10 jantan), dan Blitar (15 betina dan 11 jantan). Larva umur 10 hari dipelihara selama empat bulan. Selanjutnya dilakukan penjarangan sebesar 50% dan benih dipelihara selama 14 bulan untuk dilakukan seleksi dengan panduan hasil sampling 250 ekor individu setiap populasi. Seleksi terhadap calon induk dilakukan saat umur 18 bulan pada populasi jantan dan betina secara terpisah dengan memilih berdasarkan 10% bobot ikan yang terbaik. Calon induk yang terseleksi kemudian dipelihara hingga matang gonad, kemudian dipilih sebanyak 150 pasang dan dipijahkan secara massal. Didapatkan respons positif dari hasil seleksi berdasarkan bobot ikan, yaitu 49,89 g atau 3,66% (populasi ikan jantan) dan 168,47 g atau 11,43% (populasi ikan betina). Nilai heritabilitas untuk bobot ikan adalah 0,238 (jantan) dan 0,505 (betina).Punten carp breeding programs were carried out by individual selection for body weight trait. The base population for selection activities were conducted by mass breeding of parent consisted of 20 female and 21 male collected from area Punten, eight female and six male (Kepanjen), seven female and 12 male (Kediri), 27 female and 10 male (Sragen), 15 female and 11 male (Blitar). Larvae 10 days old reared for four moths. Then after spacing out 50% of total harvest, the offspring reared for 14 months for selection activity based on the sampling of 250 individual each population. Selection of broodstock candidates performed since 18 months age on male and female populations separately by selecting based on 10% of fish with best body weight. Candidates selected broodstocks were then maintained until mature. In oder to produce the next generation 150 pairs were sets and held for mass spawning. The results revealed that selection response were positive, 49.89 g (3.66%) for male and 168.47 (11.43%) for female. Heritability for body weight is 0.238 (male) and 0.505 (female).

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