Genet. Sel. Evol. 35 (2003) 43-63
DOI: 10.1051/gse:2002035

Pedigree analysis of eight Spanish beef cattle breeds

Juan Pablo Gutiérrez^a, Juan Altarriba^b, Clara Díaz^c, Raquel Quintanilla^d, Javier Cañón^a and Jesús Piedrafita<sup>d

a</sup>  Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain
^b  Departamento de Anatomía y Genética, Facultad de Veterinaria, Universidad de Zaragoza, 50013 Zaragoza, Spain
^c  Departamento de Mejora Genética Animal, INIA, Carretera de la Coruña, Km 7, 28040 Madrid, Spain
^d  Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain

(Received 16 November 2001; accepted 7 August 2002)

Abstract
The genetic structure of eight Spanish autochthonous populations (breeds) of beef cattle were studied from pedigree records. The populations studied were: Alistana and Sayaguesa (minority breeds), Avileña - Negra Ibérica and Morucha ("dehesa" breeds, with a scarce incidence of artificial insemination), and mountain breeds, including Asturiana de los Valles, Asturiana de la Montaña and Pirenaica, with extensive use of AI. The Bruna dels Pirineus breed possesses characteristics which make its classification into one of the former groups difficult. There was a large variation between breeds both in the census and the number of herds. Generation intervals ranged from 3.7 to 5.5 years, tending to be longer as the population size was larger. The effective numbers of herds suggest that a small number of herds behaves as a selection nucleus for the rest of the breed. The complete generation equivalent has also been greatly variable, although in general scarce, with the exception of the Pirenaica breed, with a mean of 3.8. Inbreeding effective population sizes were actually small (21 to 127), especially in the mountain-type breeds. However, the average relatedness computed for these breeds suggests that a slight exchange of animals between herds will lead to a much more favourable evolution of inbreeding. The effective number of founders and ancestors were also variable among breeds, although in general the breeds behaved as if they were founded by a small number of animals (25 to 163).

Key words: beef breeds / inbreeding / probability of gene origin / conservation

Correspondence and reprints: Juan Pablo Gutiérrez
    e-mail: gutgar@vet.ucm.es

© INRA, EDP Sciences 2003