Advances in the Brazilian animal genetic resources conservation programme

Abstract

SummaryBrazil has various species of domestic animals which developed from breeds brought by the Portuguese settlers soon after the discovery. Over the last five centuries, these breeds have been submitted to natural selection in particular environments and therefore today, they present characteristics adapted to the specific environmental conditions. From the beginning of this century, some exotic breeds, selected in temperate regions, have begun to be imported. Although more productive, these breeds lack adaptation traits, such as resistance to disease and parasites found in breeds considered to be“native” but even so, little by little, they have substituted the native breeds to such an extent that the latter are, today, in danger of extinction. To avoid the loss of this important genetic material, Brazil created an Animal Genetics Resource Conservation Programme, coordinated by the National Research Centre for Genetic Resources and Biotechnology (Cenargen) of the Brazilian Agricultural Research Corporation (EMPRAPA). The conservation has been carried out by various Research Centres of EMPRAPA, Universities, State Research Corporations, as well as by private farmers, with a single coordinator at national level, Cenargen. The conservation is being carried out through Conservation Nuclei, situated in the habitats where the animals have been subjected to natural selection (in situ), and by the storage of semen and embryos (ex situ). The recently created Animal Genetics Laboratory of Cenargen allowed genetic characterisation studies on cattle and horse breeds to begin, and, in the near future, work with asses, buffalo and sheep will be conducted‥ From the results of this research it will be possible to compare the native breeds and estimate genetic distances between them. The harmonisation of chosen micro-satellites with those which have been used in other Latin America and Iberian Peninsula countries will be extremely useful for comparative studies and will allow future exchange of germplasm between countries.

Genetic diversity and differentiation of exotic and American commercial cattle breeds raised in Brazil

“…This evidence suggested that the effective population number of the analyzed breeds might be considerably large. The highest F IS values observed for the specialized exotic breeds Guzerat and Holstein (Table 2) were consistent with the history of intense artificial selection within these populations (Mariante et al, 1999). The dendrogram based on the Nei DA genetic distance measures (Figure 1) presents the Senepol breed in an isolated clade among taurine populations.…”

“…The racial standards for zebuine breeds were only described and implemented in 1938 (Josahkian, 2000). Therefore, genetically pure herds directly descended from imported animals of both genders and without taurine gene introgression are very rare nowadays (Mariante et al, 1999). This last hypothesis was corroborated by the melted pattern of admixture observed for the zebuine breeds in Bayesian analysis conducted using STRUCTURE (Figure 2).…”

“…These animals resulted, in the large part, from absorbing crossbreeding between zebuine bulls imported from different regions of India and local taurine dams (Mariante et al, 1999). Furthermore, Brazilian Creole cattle also contributed to the formation of some American derivatives of zebuine breeds (such as Tabapuã) (Mariante et al, 1999;Dani et al, 2008). It has been shown that Latin American Creole breeds may carry either European-or Africanoriginated taurine DNA (Lirón et al, 2006;Ginja et al, 2010).…”

Parâmetros genéticos para características de desempenho em ovinos naturalizados Sul-Mato-Grossenses

“…Os ovinos pantaneiros são oriundos de cruzamentos entre as raças que foram trazidas pelos colonizadores portugueses e espanhóis logo após o descobrimento (MARIANTE et al, 1999). Estes animais são encontrados em fazendas mais isoladas da região, sem nenhum controle reprodutivo ou sanitário, vivendo há muitos anos praticamente sob seleção natural (VARGAS JUNIOR et al, 2011).…”

Molecular markers for genetic diversity and phylogeny research of Brazilian sheep breeds

“…Over the years, these breeds were subjected to natural selection of local environmental and edaphoclimatic conditions, resulting in breeds that are currently considered naturalized, locally adapted, or native (Mariante et al, 1999). Agricultural census data collected by the Brazilian Institute of Geography and Statistics put the Brazilian sheep population at more than 17 million animals, center mainly in the southern and northeastern regions of the country.…”