Evaluación de métodos de corrección para efectos ambientales para peso al destete en corderos Suffolk

Autor: Yiming Sulaiman, César Flores-Serrano, Antonio Ortiz-Hernández, Rosa Berta Angulo-Mejorada, Hugo H. Montaldo
Jazyk: Spanish; Castilian
Rok vydání: 2009
Předmět:
Zdroj: Universidad Nacional Autónoma de México
UNAM
Redalyc-UNAM
Veterinaria México (México) Num.3 Vol.40
Popis: "Data of weaning weights (WW) from 2 172 Suffolk lambs with complete genealogical information, obtained from a flock in central Mexico from 1992 to 2004, were analyzed using mixed linear models with direct and maternal effects, to generate correction factors and to compare different methods for the adjustment of sex, type of birth and age of the mother effects. The methods compared were: analysis of weaning weights with a complete mixed model (PDMOD), analysis of WW preadjusted to 68 days and for sex and age of the mother-type of birth with factors developed from this population (PD68PRE), analysis of WW adjusted to 68 days with a complete model (PD68MOD) and analysis of WW preadjusted to 68 days and for sex, age of the mother and type of birth with factors developed for the Suffolk population of the United States of America (PD68USA). The effects of year of birth, sex, type of birth, age of the mother, year of birth and age of the mother interaction and the linear and quadratic effects of weaning age were all significant (P < 0.01). The inclusion of all the effects in the model gave slightly smaller residual coefficients of variation with reductions . 0.51%, compared to preadjusted data with correction factors generated either in the flock or adapted from those suggested for the Suffolk population of the United States of America. Small differences between methods in the ranking of the animals according to the genetic evaluations based on empirical BLUP's for direct and maternal genetic effects were found, with Spearman's correlation values . 0.96."
Databáze: OpenAIRE
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