Genetic Diversity in the Portuguese Mertolenga Cattle Breed Assessed by Pedigree Analysis
2020
Author
Nuno Carolino (Instituto Nacional de Investigação Agrária e Veterinária, Fonte Boa, 2005-048 Vale de Santarém, Portugal), Andreia Vitorino (Instituto Nacional de Investigação Agrária e Veterinária, Fonte Boa, 2005-048 Vale de Santarém, Portugal), Inês Carolino (Instituto Nacional de Investigação Agrária e Veterinária, Fonte Boa, 2005-048 Vale de Santarém, Portugal), José Pais (Associação de Criadores de Bovinos Mertolengos, Rua Diana de Liz, Apartado 466, Horta do Bispo, 7006-806 Évora, Portugal), Nuno Henriques (Associação de Criadores de Bovinos Mertolengos, Rua Diana de Liz, Apartado 466, Horta do Bispo, 7006-806 Évora, Portugal), Manuel Silveira (Ruralbit Lda, Avenida Dr. Domingos Gonçalves Sá 132, 4435-213 Rio Tinto, Portugal), António Vicente (Centro de Investigação Interdisciplinar em Sanidade Animal (CIISA), Faculdade de Medicina Veterinária—Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal)
Abstract
The Mertolenga beef cattle, currently with 27,000 breeding females in Portugal, is the largest Portuguese native breed, despite some variation in the breeding stock over the last years. The purpose of this study was to estimate parameters related to the population structure and genetic diversity and to investigate the major factors affecting genetic erosion in the breed, based on the pedigree herdbook information collected since the 1950s, including records on 221,567 animals from 425 herds. The mean generation intervals were 6.4 years for sires and 7.1 years for dams, respectively. The rate of inbreeding per year was 0.183% ± 0.020% and the correspondent effective population size was 38.83. In the reference population (35,017 calves born between 2015 and 2019), the average inbreeding and relatedness were 8.82% ± 10% and 2.05% ± 1.26%, respectively. The mean relationship among animals from the same and from different herds was 29.25% ± 9.36% and 1.87% ± 1.53%, respectively. The estimates for the effective number of founders, ancestors, founding herds and herds supplying sires were 87.9, 59.4, 21.4 and 73.5, respectively. Although the situation of the Mertolenga breed is not alarming, these results indicate the need to adopt measures to maintain the genetic variability of the population.
DOI
Journal
Animals
Source
DOAJ