Response to selection for litter size in Danish Landrace pigs: a Bayesian analysis

SUMMARYAn experiment was carried out with mice over 24 generations to measure the response obtained to selection for litter size and litter weight at weaning on two dietary regimes designated normal and diluted. In addition, control groups bred by random mating were maintained on each diet. The stock were maintained on the diets from generation 0–3 after which time selection for the traits started and continued up to generation 17. After generation 17 for a further 6 generations, all selection stopped and half of each group was switched on to the other diet, while the remaining half continued as before.No significant response was obtained to selection for either litter size or litter weight at weaning.The diets provided did not bring about a differential response to selection for the traits, and the response to the dietary switch was small and temporary in its effect.Due to strong maternal effects and low heritability, little genetic improvement was obtained by selection for litter size and litter weight at weaning in these mice.

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Correlated response to selection for litter size in pigs: I. Growth, fat deposition, and feeding behavior traits

Journal of Animal Science ◽

10.2527/2002.80102556x ◽

2002 ◽

Vol 80 (10) ◽

pp. 2556 ◽

Cited By ~ 2

Author(s):

J. Estany ◽

D. Villalba ◽

J. Tibau ◽

J. Soler ◽

D. Babot ◽

...

Keyword(s):

Feeding Behavior ◽

Litter Size ◽

Fat Deposition ◽

Correlated Response ◽

Response To Selection ◽

Selection For

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Estimation of Genetic Parameters and Selection Response for Reproductive and Growth Traits in Rideau-Arcott sheep

Canadian Journal of Animal Science ◽

10.1139/cjas-2019-0152 ◽

2020 ◽

Author(s):

Mohammed Naser Boareki ◽

Luiz Brito ◽

Angela Cánovas ◽

V.R. Osborne ◽

Flavio S Schenkel

Keyword(s):

Litter Size ◽

Genetic Parameters ◽

Growth Traits ◽

Reproductive Traits ◽

Selection Response ◽

Direct Selection ◽

Correlated Response ◽

Response To Selection ◽

Weaning Weight ◽

Selection For

The goal of this study was to estimate genetic parameters and predict direct and correlated response to selection for lamb growth traits and ewe reproductive traits, based on single trait selection or combining multiple traits in an optimum index that targets total litter post-weaning weight in the first lambing as the main selection goal. Heritability estimates ranged from 0.04 to 0.19. Genetic correlations between growth and reproductive traits ranged from -0.24 to 0.15. The indirect response to selection for reproductive traits in later lambings, by selecting on first lambing performance, was 11 to 25% greater than direct selection. The response to indirect selection for composite reproductive traits, i.e. total weaning weight or total post-weaning weight, by selecting on individual lamb weaning weight or post-weaning weight was 1 to 69% greater than direct selection, but it was accompanied by a negative response on litter size. However, combining alternate growth and reproductive traits in optimum selection index resulted in correlated response of up to 96% greater than direct selection response for reproductive traits without a negative response on litter size. Therefore, multiple trait selection using an index of component traits was more effective than direct selection for a composite trait.

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Correlated response to selection for litter size in pigs: I. Growth, fat deposition, and feeding behavior traits1

Journal of Animal Science ◽

10.1093/ansci/80.10.2556 ◽

2002 ◽

Vol 80 (10) ◽

pp. 2556-2565 ◽

Cited By ~ 1

Author(s):

J. Estany ◽

D. Villalba ◽

J. Tibau ◽

J. Soler ◽

D. Babot ◽

...

Keyword(s):

Feeding Behavior ◽

Litter Size ◽

Fat Deposition ◽

Correlated Response ◽

Response To Selection ◽

Selection For

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Correlated response to selection for litter size in pigs: II. Carcass, meat, and fat quality traits1

Journal of Animal Science ◽

10.1093/ansci/80.10.2566 ◽

2002 ◽

Vol 80 (10) ◽

pp. 2566-2573

Author(s):

J. Estany ◽

D. Villalba ◽

M. Tor ◽

D. Cubiló ◽

J. L. Noguera

Keyword(s):

Litter Size ◽

Correlated Response ◽

Response To Selection ◽

Fat Quality ◽

Selection For

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Bayesian Analysis of Response to Selection: A Case Study Using Litter Size in Danish Yorkshire Pigs

Genetics ◽

10.1093/genetics/156.1.283 ◽

2000 ◽

Vol 156 (1) ◽

pp. 283-295

Author(s):

D Sorensen ◽

A Vernersen ◽

S Andersen

Keyword(s):

Bayesian Analysis ◽

Litter Size ◽

Genetic Model ◽

Correlated Response ◽

Model Assessment ◽

Response To Selection ◽

Probability Interval ◽

Posterior Mean ◽

Assessment Study ◽

Yorkshire Pigs

Abstract Implementation of a Bayesian analysis of a selection experiment is illustrated using litter size [total number of piglets born (TNB)] in Danish Yorkshire pigs. Other traits studied include average litter weight at birth (WTAB) and proportion of piglets born dead (PRBD). Response to selection for TNB was analyzed with a number of models, which differed in their level of hierarchy, in their prior distributions, and in the parametric form of the likelihoods. A model assessment study favored a particular form of an additive genetic model. With this model, the Monte Carlo estimate of the 95% probability interval of response to selection was (0.23; 0.60), with a posterior mean of 0.43 piglets. WTAB showed a correlated response of −7.2 g, with a 95% probability interval equal to (−33.1; 18.9). The posterior mean of the genetic correlation between TNB and WTAB was −0.23 with a 95% probability interval equal to (−0.46; −0.01). PRBD was studied informally; it increases with larger litters, when litter size is >7 piglets born. A number of methodological issues related to the Bayesian model assessment study are discussed, as well as the genetic consequences of inferring response to selection using additive genetic models.

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