EFFECT OF SELECTION ON FEED UTILIZATION AND CARCASS SCORE EN SWINE

1970 ◽  
Vol 50 (3) ◽  
pp. 575-584 ◽  
Author(s):  
C. BERNARD ◽  
M. H. FAHMY
Keyword(s):  
Body Weight ◽  
Genetic Correlation ◽  
Genetic Improvement ◽  
Body Weight Gain ◽  
Feed Utilization ◽  
Phenotypic Correlation ◽  
Population Selection ◽  
Yorkshire Pigs ◽  
Selection For ◽  
Selection Differentials

Selection for feed utilization (FU) and carcass score (CS) based on full sib performance was practiced within three lines of Yorkshire pigs during ten generations. Line 1 was selected solely for FU, line 2 for CS and line 3 for the two traits combined in an index. Line 2 served as a control for lines 1 and 3 in FU and line 1 as a control for lines 2 and 3 in CS. Feed utilization was expressed as the amount of feed required per kilogram body weight gain. Carcass score was based on length, backfat thickness, loin eye area and belly grade measured on pigs marketed at 90 kg liveweight. Selection differentials for FU averaged 0.198 and 0.208 kg per generation for lines 1 and 3, respectively, while CS differentials were 7.2 and 7.4 points per generation for lines 2 and 3, respectively. Heritability estimates based on full sib performance and converted to individual bases were 0.16 for FU and 0.43 for CS. The phenotypic correlation between the two traits was −0.25 and the genetic correlation −0.55. Responses to selection for FU were 0.09 and 0.24 kg per generation for lines 1 and 3, respectively, while for CS they were 0.77 and 0.97 points for lines 2 and 3, respectively. Compared with the parental means, this represented a genetic improvement of 0.25 and 0.66% per generation for FU in lines 1 and 3, and 1.06 and 1.33% per generation for CS in lines 2 and 3, respectively. The realized responses in lines 1 and 3 to selection for FU Were 58 and 148% of the expectation, and 58 and 72% for lines 2 and 3 in CS. Due to larger selection differentials in line 3, along with a strong positive genetic correlation between the two traits observed in this particular population, selection for the combined traits was 1.35 and 1.10% more effective in improving FU and CS, respectively, than selection for these traits individually.

EFFECT OF SELECTION FOR CARCASS SCORE ON THE GENETIC IMPROVEMENT OF ITS COMPONENTS IN SWINE

1970 ◽  
Vol 50 (3) ◽  
pp. 585-592 ◽  
Author(s):  
M. H. FAHMY ◽  
C. BERNARD
Keyword(s):  
Analysis Of Variance ◽  
Genetic Improvement ◽  
Genetic Correlations ◽  
Feed Utilization ◽  
Backfat Thickness ◽  
Yorkshire Pigs ◽  
Selection For ◽  
Heritability Estimates ◽  
Sole Criterion ◽  
Three Components

Selection for carcass score was practiced for ten generations in two separate lines of Yorkshire pigs. Three components of the score were studied: carcass length, loin eye area, and backfat thickness. In line 2, carcass score was the sole criterion of selection, while in line 3, it was combined with feed utilization into an overall merit. Line 1, selected solely for feed utilization, served as a control. Carcass length and loin eye area increased by approximately 2 and 9%, respectively, in both lines. However, backfat thickness also increased by about 3% in line 2 and 0.4% in line 3. Pooled heritability estimates derived from the analysis of variance and the regression of offspring on mid-parent were 0.64 for carcass length, 0.48 for loin eye area and 0.67 for backfat thickness. Genetic correlations among the components of carcass score, between the components and carcass score and between the components and feed utilization were moderately high and favorable for combined genetic improvement of all traits.

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

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).

scholarly journals Genetic correlation between traits in the ESALQ-PB1 maize population divergently selected for tassel size and ear height

2001 ◽  
Vol 58 (1) ◽  
pp. 119-123 ◽  
Author(s):  
Austeclínio Lopes Farias Neto ◽  
José Branco de Miranda Filho
Keyword(s):  
Genetic Correlation ◽  
Correlation Coefficients ◽  
Divergent Selection ◽  
Phenotypic Correlation ◽  
Base Population ◽  
Branch Number ◽  
Maize Population ◽  
Tassel Branch Number ◽  
Ear Height ◽  
Selection For

Full-sib and selfed (S1) progenies were obtained from sub-populations of ESALQ-PB1, divergently selected for tassel size (T+ and T-) and ear height (E+ and E-), and used for estimating genetic and phenotypic correlation coefficients between traits. The analyzed traits were: EW- total ear weight (g/plant), PH- plant height (cm), EH- ear height (cm), TB- tassel branch number and TL- tassel length. The highest genetic (rG) and phenotypic (rF) correlation was observed for the combination PH x EH, as expected, with average of 0.800 and 0.778, respectively over sub-populations and locations. It is apparent that divergent selection for tassel size did not affect greatly the correlation between PH and EH in the full sib progenies, but in the inbred progenies the correlation was smaller in the sub-population selected for larger tassels. Genetic correlation between PH and EH with tassel traits was always positive but ranged from 0.020 to 0.668 in Piracicaba and from 0.06 to 0.309 in Rio Verde. Genetic correlation between PH and EH with yield (EW) also was positive in the range of 0.087 to 0.503. EH showed higher correlation with EW in relation to PH x EW and differences were larger in the sub-populations divergently selected for ear height. Correlation between tassel traits with other traits was positive in most of instances and a lack of consistency was observed among sub-populations. Generally the coefficients of genetic and phenotypic correlation differed substantially from the estimates in the base population ESALQ-PB1 before divergent selection for tassel size and ear placement. Divergent selection affected the correlation between traits under unpredicted and varying magnitudes.

HERITABILITIES AND GENETIC CORRELATIONS FOR ULTRASONIC BACKFAT MEASUREMENTS, GROWTH AND CARCASS TRAITS IN SWINE

1982 ◽  
Vol 62 (3) ◽  
pp. 665-670 ◽  
Author(s):  
D. C. JEFFRIES ◽  
R. G. PETERSON
Keyword(s):  
Key Words ◽  
Genetic Correlation ◽  
Genetic Parameters ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Phenotypic Correlation ◽  
Ultrasonic Measurements ◽  
Yorkshire Pigs ◽  
Daily Gain ◽  
Season Interaction

Genetic parameters were estimated for 2403 purebred Yorkshire pigs over a 2-yr period, representing 21 sires. The traits studied included average daily gain, age adjusted to 90 kg, ultrasonic measurements of backfat at the mid-back and loin positions, total and adjusted total ultrasonic backfat and corresponding carcass backfat measurements. Least squares analyses were used to estimate and adjust for the effects of sex, year-season and sex by year-season interaction. Heritabilities and genetic correlations were calculated for all traits using both half- and full-sib estimates. Adjusted age and adjusted total ultrasonic backfat measurements were found to have the highest heritabilities of the live traits in this study. Estimates of heritability for adjusted age and adjusted total ultrasonic backfat were 0.24 ± 0.10 and 0.26 ± 0.10 based on half-sib and 0.56 ± 0.07 and 0.41 ± 0.06 from full-sib analyses. The genetic correlation between these two traits was −0.07 ± 0.28 based on the half-sib method. The total phenotypic correlation was −0.01 ± 0.02. Key words: Swine, ultrasonic backfat, heritabilities, genetic correlations

scholarly journals PSVIII-38 Late-Breaking Abstract: Estimating genetic parameters of feed efficiency traits in American mink

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 347-347
Author(s):  
Pourya Davoudi ◽  
Duy Ngoc Do ◽  
Guoyu Hu ◽  
Siavash Salek Ardestani ◽  
Younes Miar
Keyword(s):  
Body Weight ◽  
Genetic Correlation ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
American Mink ◽  
Genetic Correlations ◽  
Final Body Weight ◽  
Selection For

Abstract Feed cost is the major input cost in the mink industry and thus improvement of feed efficiency through selection for high feed efficient mink is necessary for the mink farmers. The objective of this study was to estimate the heritability, phenotypic and genetic correlations for different feed efficiency measures, including final body weight (FBW), daily feed intake (DFI), average daily gain (ADG), feed conversion ratio (FCR) and residual feed intake (RFI). For this purpose, 1,088 American mink from the Canadian Center for Fur Animal Research at Dalhousie Faculty of Agriculture were recorded for daily feed intake and body weight from August 1 to November 14 in 2018 and 2019. The univariate models were used to test the significance of sex, birth year and color as fixed effects, and dam as a random effect. Genetic parameters were estimated via bivariate models using ASReml-R version 4. Estimates of heritabilities (±SE) were 0.41±0.10, 0.37±0.11, 0.33±0.14, 0.24±0.09 and 0.22±0.09 for FBW, DFI, ADG, FCR and RFI, respectively. The genetic correlation (±SE) was moderate to high between FCR and RFI (0.68±0.15) and between FCR and ADG (-0.86±0.06). In addition, RFI had low non-significant (P > 0.05) genetic correlations with ADG (0.04 ± 0.26) and BW (0.16 ± 0.24) but significant (P < 0.05) high genetic correlation with DFI (0.74 ± 0.11) indicating that selection for lower RFI will reduce feed intake without adverse effects on the animal size and growth rate. The results suggested that RFI can be implemented in genetic/genomic selection programs to reduce feed intake in the mink production system.

scholarly journals EFFECT OF SELECTION ON HERITABILITY AND GENETIC CORRELATION OF TWO QUANTITATIVE TRAITS IN MICE

1974 ◽  
Vol 16 (3) ◽  
pp. 599-609 ◽  
Author(s):  
T. K. Cheung ◽  
R. J. Parker
Keyword(s):  
Body Weight ◽  
Genetic Correlation ◽  
Quantitative Traits ◽  
Random Mating ◽  
Tail Length ◽  
Control Group ◽  
Mass Selection ◽  
Initial Population ◽  
Significant Difference ◽  
Selection For

The effects of different intensities of single trait directional selection on the heritability and genetic correlation of two quantitative traits in random mating populations of mice were observed during 14 generations. The initial population was divided at random into five groups (A, B, C, D and E). Group A and Group B were under 30% and 60% mass selection for large 6-week body weight, respectively. Group C and Group D were under 30% and 60% mass selection for long 6-week tail length, respectively. Group E acted as control group with no selection applied. In all groups, the parent population consisted of 15 males and 30 females each generation, mated at random.Direct selection had no apparent effect on the heritability of either the trait under selection or the correlated trait over the 14 generations. Heritability of 6-wk tail length was higher than the heritability of 6-wk body weight. Estimates of heritability of 6-wk tail length ranged from 0.15 ± 0.22 to 0.68 ± 0.24, while estimates of heritability of 6-wk body weight ranged from 0.05 ± 0.17 to 0.33 ± 0.09. There was no significant difference among the estimates of genetic correlation between the two traits in the five selection groups. Estimates of realized genetic correlation between 6-wk body weight and 6-wk tail length seemed to indicate that more intense selection led to some decrease in genetic correlation between the two traits.

Genetic improvement of farmed tilapias: Response to five generations of selection for increased body weight at harvest in Oreochromis niloticus and the further impact of the project

Aquaculture ◽  
2017 ◽  
Vol 468 ◽  
pp. 206-217 ◽  
Author(s):  
Hans B. Bentsen ◽  
Bjarne Gjerde ◽  
Ambekar E. Eknath ◽  
Marietta S. Palada de Vera ◽  
Ravelina R. Velasco ◽  
...  
Keyword(s):  
Body Weight ◽  
Oreochromis Niloticus ◽  
Genetic Improvement ◽  
Selection For

Genetic and phenotypic relationships between food intake, growth, efficiency and body composition of mice post weaning and at maturity

1998 ◽  
Vol 67 (1) ◽  
pp. 171-182 ◽  
Author(s):  
J. A. Archer ◽  
W. S. Pitchford ◽  
T. E. Hughes ◽  
P. F. Parnell
Keyword(s):  
Body Composition ◽  
Genetic Variation ◽  
Food Intake ◽  
Genetic Correlation ◽  
Body Fat ◽  
Average Daily Gain ◽  
Phenotypic Correlation ◽  
Daily Food Intake ◽  
Daily Food ◽  
Selection For

AbstractGenetic and phenotypic variation in post-weaning growth, food intake, efficiency and body composition of mice post weaning and at maturity, were examined to determine whether genetic variation in efficiency exists and to predict likely responses to selection for increased food efficiency in post-weaning animals. Genetic variation was found for average daily gain, mid-weight, daily food intake and proportion of body fat both post weaning and at maturity. Residual food intake calculated from phenotypic regression had a heritability of 0·27 (s.e. 0·06) post weaning and 0·24 (s.e. 0·08) at maturity, and was very similar to residual food intake calculated using genetic (co)variances, indicating genetic variation in efficiency exists in post-weaning and mature mice. Although the phenotypic correlation between residual food intake post weaning and at maturity was low (0·29), the genetic correlation was moderate (0·60). This suggests that selection for efficiency in young animals will lead to a correlated improvement in maintenance efficiency of mature animals. Genetic correlation estimates suggest that correlated responses in other traits would include a concomitant decrease in post-weaning food intake, a slight increase in weight at weaning, a slight increase in post-weaning fat proportion and little or no change in post-weaning growth. In mature animals there will be an associated decrease in daily food intake and a slight decrease in mature size and body fat proportion. The results suggest that residual food intake of young animals might be a suitable selection criteria for use in livestock species to improve efficiency in young animals and also in the breeding herd.

scholarly journals Effect of disruptive selection for body conformation on age variations of femoral morphometrie traits, in mice

1999 ◽  
Vol 42 (2) ◽  
pp. 201-210
Author(s):  
L. Hinrichsen ◽  
D. Mana ◽  
R. Di Masso ◽  
M. T. Font
Keyword(s):  
Body Weight ◽  
Tail Length ◽  
Whole Body ◽  
Disruptive Selection ◽  
Phenotypic Correlation ◽  
Control Line ◽  
Genetic Determination ◽  
Body Conformation ◽  
Age Variations ◽  
Selection For

Abstract. The effect of disruptive selection for body conformation on body weight and length, tail length, and femur weight and length at different stages of development (21, 42, 63, and 120 days of age) was analysed in four mouse lines of the CBi stock selected for (CBi+, CBi-) and against (CBi/L, CBi/C) the phenotypic correlation between body weight and tail length, and die unselected control line CBi. As expected, body weight and tail length distributed according to the selection criteria; rrunk length (whole body length minus tail length) behaved as body welght at all ages. CBi/L had the highest femoral length (p < 0.01), and CBi/C attained the highest femoral weight (p < 0.01). CBi+ and CBi-, harmonically large or small, differed between them and from the control line in both variables (p < 0.001). These findings further corroborate the proposal that bone mass is markedly affected by the skeleton function as support of soft tissues. The allometric analysis ofthe regression of femur weight on femur length suggests that, in this model, a) the demand posed by the selective pressure forced each genotype to find a unique Solution, b) this response is sex-dependent, and c) genetic determination ofthe parameters involved in this allometric relationship is, at least, partially independent.

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