Estimation of genetic parameters for productive life, reproduction, and milk-production traits in US dairy goats.

Autor: Castañeda-Bustos VJ; Colegio de Postgraduados, Campus Montecillo, Montecillo, Estado de México 56230, Mexico., Montaldo HH; Departamento de Genética y Bioestadística, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Ciudad Universitaria, DF 04510, Mexico. Electronic address: montaldo@unam.mx., Torres-Hernández G; Colegio de Postgraduados, Campus Montecillo, Montecillo, Estado de México 56230, Mexico., Pérez-Elizalde S; Colegio de Postgraduados, Campus Montecillo, Montecillo, Estado de México 56230, Mexico., Valencia-Posadas M; División de Ciencias de la Vida, Campus Irapuato-Salamanca, Universidad de Guanajuato, Ex Hacienda El Copal, Irapuato, Guanajuato 36500, Mexico., Hernández-Mendo O; Colegio de Postgraduados, Campus Montecillo, Montecillo, Estado de México 56230, Mexico., Shepard L; American Dairy Goat Association, Spindale, NC 28160.
Jazyk: angličtina
Zdroj: Journal of dairy science [J Dairy Sci] 2014; Vol. 97 (4), pp. 2462-73. Date of Electronic Publication: 2014 Feb 15.
DOI: 10.3168/jds.2013-7503
Abstrakt: Heritabilities and correlations for milk yield (MY), fat yield (FY), protein yield (PY), combined fat and protein yield (FPY), fat percentage (F%), protein percentage (P%), age at first kidding (AFK), interval between the first and second kidding (KI), and real and functional productive life at 72mo (FPL72) of 33,725 US dairy goats, were estimated using animal models. Productive life was defined as the total days in production until 72mo of age (PL72) for goats having the opportunity to express the trait. Functional productive life was obtained by correcting PL72 for MY, FY, PY, and final type score (FS). Six selection indexes were used, including or excluding PL72, with 6 groups of different economic weights, to estimate the responses to selection considering MY, FY, PY, and PL72 as selection criteria. The main criteria that determined the culling of a goat from the herd were low FS, MY, and FY per lactation. Heritability estimates were 0.22, 0.17, 0.37, 0.37, 0.38, 0.39, 0.54, 0.64, 0.09, and 0.16 for PL72, FPL72, MY, FY, PY, FPY, F%, P%, KI, and AFK, respectively. Most genetic correlations between the evaluated traits and PL72 or FPL72 were positive, except for F% (-0.04 and -0.06, respectively), P% (-0.002 and -0.03, respectively), and AFK (-0.03 and -0.01, respectively). The highest genetic correlations were between FPL72 and MY (0.39) and between PL72 and MY (0.33). Most phenotypic correlations between the traits evaluated and FPL72 and PL72 were positive (>0.23 and >0.26, respectively), except for F% (-0.004 and -0.02, respectively), P% (-0.05 and -0.02), KI (-0.01 and -0.07), and AFK (-0.08 and -0.08). The direct selection for PL72 increased it by 102.28d per generation. The use of MY, FY, PY, KI, or AFK as selection criteria increased PL72 by 39.21, 27.33, 35.90, -8.28, or 2.77d per generation, respectively. The inclusion of PL72 as selection criterion increased the expected response per generation from 0.15 to 17.35% in all selection indices studied.
(Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE