Abstract
Simple SummaryThe conservation and maintenance of genetic diversity is one of the priorities of the Convention of Biological Diversity and is included in the United Nations (UN’s) Sustainable Development Goals. The evaluation of the genetic variability of a breed is fundamental for its future use in a sustainable way, being indispensable to outline a successful conservation or improvement strategy. Preserving genetic diversity in a population is one of the main objectives for a breed conservation program. Nevertheless, the correct management of genetic diversity is also essential for the adaptation of a population to a new environment, production system or genetic improvement. For the purpose of population monitoring, assessing changes in genetic variability and genetic erosion in animal populations, many methodologies based on pedigree analyses of inbreeding and relationships, and on the probability of genetic origin from different herds, founders and ancestors, have been used. This study presents several genetic diversity indicators in a Portuguese native cattle breed, Mertolenga, assessed by pedigree analysis, and demonstrates the usefulness of these indicators and how they can be used in the genetic management of a breed.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.
Highlights
The main goal of this study is to describe genetic diversity in the Mertolenga cattle breed that based on pedigree analysis, taking into consideration their different coat types, and identifying factors onmay pedigree analysis,the taking into consideration their different coat types, and and identifying factors that have affected population, in order to establish conservation strategies minimize further may have population, losses inaffected terms ofthe genetic diversity.in order to establish conservation strategies and minimize further losses in terms of genetic diversity
There are approximately 27,000 registered cows, including nearly 8000 cows used in purebred mating, 190 bulls and 216 herds enrolled, where about an average of 6500 pure calves were born/year over the last years
Conservation of genetic diversity is universally accepted as being essential for the sustainable use of animal genetic resources and to the future of humanity
Summary
TheMertolengabeef beefcattle cattlebreed, breed, currently currently with the largest of of thetheMertolenga with 27,00027,000breeding breedingfemales, females,is is the largest fifteenPortuguese native breeds, only of them are purebred.The rest are crossbred fifteen Portuguese native breeds, only 8000 of them are purebred. 27,000breeding breedingfemales, females,is is the largest fifteen. Portuguese native breeds, only of them are purebred. The rest are crossbred fifteen Portuguese native breeds, only 8000 of them are purebred. This this breed breed experienced census decline with international experiencedaaperiod periodofofstrong strong census decline caused by drastic changes in the livestock sector and unplanned crossbreeding with exotic breeds. Caused by drastic changes in the livestock sector and unplanned crossbreeding with exotic breeds. Mertolenga cows cows are are used used in
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
