Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Genetic improvement of laying hens viability using survival analysis
Autore:
Ducrocq, V; Besbes, B; Protais, M;
Indirizzi:
INRA, Genet Quantitat & Appl Stn, F-78352 Jouy En Josas, France INRA JouyEn Josas France F-78352 ppl Stn, F-78352 Jouy En Josas, France Hubbard ISA, Ctr Select, F-35220 Chateaubourg, France Hubbard ISA Chateaubourg France F-35220 ct, F-35220 Chateaubourg, France Hubbard ISA, F-22800 Quintin, France Hubbard ISA Quintin France F-22800Hubbard ISA, F-22800 Quintin, France
Titolo Testata:
GENETICS SELECTION EVOLUTION
fascicolo: 1, volume: 32, anno: 2000,
pagine: 23 - 40
SICI:
0999-193X(200001/02)32:1<23:GIOLHV>2.0.ZU;2-M
Fonte:
ISI
Lingua:
ENG
Soggetto:
SELECTION RESPONSE; TRAITS; MODEL; PREDICTION; LIFE;
Keywords:
survival analysis; viability; laying hens; selection;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Agriculture,Biology & Environmental Sciences
Citazioni:
23
Recensione:
Indirizzi per estratti:
Indirizzo: Ducrocq, V INRA, Genet Quantitat & Appl Stn, F-78352 Jouy En Josas, FranceINRA Jouy En Josas France F-78352 78352 Jouy En Josas, France
Citazione:
V. Ducrocq et al., "Genetic improvement of laying hens viability using survival analysis", GEN SEL EVO, 32(1), 2000, pp. 23-40

Abstract

The survival of about eight generations of a large strain of laying hens was analysed separating the rearing period (RP) from the production period (PP), after hens were housed. For RP (respectively PP), 97.8% (resp., 94.1%)of the 109 160 (resp., 100 665) female records were censored after 106 days (resp., 313 days) on the average. A Cox proportional hazards model stratified by flock (= season) and including a hatch-within-flock (HWF) fixed effect seemed to reasonably fit the RP data. For PP, this model could be further simplified to a non-stratified Weibull model. The extension of these models to sire-dam frailty (mixed) models permitted the estimation of the siregenetic variances at 0.261 +/- 0.026 and 0.088 +/- 0.010 for RP and PP, respectively. Heritabilities on the log scale were equal to 0.48 and 0.19. Non-additive genetic effects could not be detected. Selection was simulated by evaluating all sires and dams, after excluding all records from the last generation. Thee, actual parents of this last generation were distributed into four groups according to their own pedigree index. Raw survivor curves of the progeny of extreme parental groups substantially differed (e.g., by 1.7% at 300 days for PP), suggesting that selection based on solutions fromthe frailty models could be efficient, despite the very large proportion of censored records.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/12/20 alle ore 15:53:32