Fecha/hora: 12/06/2024 03:28:40

Biblioteca(s): 	INIA Las Brujas.	
Fecha corriente: 	10/09/2014	
Fecha de la última actualización: 	15/10/2019	
Autoria: 	CIAPPESONI, G.; GOLDBERG, V.; GIMENO, D.	
Afiliación: 	CARLOS GABRIEL CIAPPESONI SCARONE, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; VIRGINIA GOLDBERG BIANCHI, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; DIEGO GIMENO, SUL (Secretariado Uruguayo de la Lana).	
Título: 	Estimates of genetic parameters for worm resistance, wool and growth traits in Merino sheep of Uruguay.	
Año de publicación: 	2013	
Fuente/Imprenta: 	Livestock Science, 2013, v.157, no.1, p.65-74.	
Volumen: 	157 (1)	
Páginas: 	65-74	
ISSN: 	1871-1413	
DOI: 	10.1016/j.livsci.2013.07.011	
Idioma: 	Inglés	
Notas: 	Article history: Received 19 October 2012 / Received in revised form 19 July 2013 / Accepted 24 July 2013.	
Contenido: 	ABSTRACT.

The genotype of an individual and the environment as the maternal ability of its dam have substantial effects on the phenotype expression of many production traits. The aim of the present study was to estimate the (co)variance components for worm resistance, wool and growth traits in Merino sheep, testing the importance of maternal effects and to determine the most appropriate model for each trait. The traits analyzed were Greasy Fleece Weight (GFW), Clean Fleece Weight (CFW), average Fibre Diameter (FD), Coefficient of Variation of FD (CVFD), Staple Length (SL), Comfort Factor (CF30), Weaning Weight (WWT), Yearling Body Weight (YWT) and Faecal worm Egg Count (FEC). The data were recorded during a 15-year period from 1995 to 2010, from Uruguayan Merino stud flocks. A Bayesian analysis was performed to estimate (co)variance components and genetic parameters. By ignoring or including maternal genetic or environmental effects, five different univariate models were fitted in order to determine the most effective for each trait. For CVFD and YWT, the model fitting the data best included direct additive effects as the only significant random source of variation. For GFW, CFW, FD, SL and CF30 the most appropriate model included direct-maternal covariance; while for FEC included maternal genetics effects with a zero direct-maternal covariance. The most suitable model for WWT included correlated maternal genetic plus maternal permanent environmental effects. The estimates of direct heritability were moderate to high and ranged from 0.15 for log transformed FEC to 0.74 for FD. Most of the direct additive genetic correlation (rg) estimations were in the expected range for Merino breed. However, the estimate of rg between FEC and FD was unfavourable (&#8722;0.18±0.03). In conclusion, there is considerable genetic variation in the traits analyzed, indicating the potential to make genetic progress on these traits. This study showed that maternal effects are influencing most of traits analyzed, thus these effects should be considered in Uruguayan Merino breeding programs; since the implementation of an appropriate model of analysis is critical to obtain accurate estimates.	
Palabras-Clave: 	COVARIANZA GENÉTICA; OVIS ARIES.	
Thesagro: 	COVARIANZA; LANA.	
Categoría del tema: 	L60 Taxonomía y geografía de los animales	
Registro original: 	INIA Las Brujas (LB)	
Ejemplares: 	LB - (100043-1) - PXI - AP - DD - PP/LIVESTOCK SCI./2013 -  -  - DIS