Diversidade e estrutura genética de ovinos crioulos lanados do Brasil

Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Genética e Morfologia, Laboratório de Genética, 2008.O conhecimento da variabilidade genética existente em raças locais de animais zootécnicos é importante para a conservação do patrimônio genético e para programas de melhoramento animal. O objetivo geral deste trabalho foi analisar a diversidade e a variabilidade genética do ovino Crioulo Lanado brasileiro por meio de marcadores genéticos do tipo RAPD e SSRs. As amostras analisadas representaram o rebanho de conservação da Empresa Brasileira de Pesquisa Agropecuária - EMBRAPA, bem como as populações de ovinos crioulos existentes na área de ocorrência. Os resultados indicaram que a variabilidade genética total da raça Fronteira e do ecótipo Serrana não está representada no rebanho de conservação da EMBRAPA nem nos demais rebanhos amostrados. Os animais mantidos pela EMBRAPA apresentaram mais introgressão de Corriedale que os da população externa. Em todas as análises o ecótipo Zebua foi o mais dissimilar entre os crioulos. _________________________________________________________________________________________ ABSTRACTThe knowledge of the existing genetic variability in local breeds of livestock is important for the conservation genetics and for programs of animal breeding. The general objective of this research was to analyze the diversity and the genetic variability of Brazilian Creole Wool Sheep raised in the Southearn region of the country through the utilization of molecular markers (RAPD and STR). The analyzed samples represented the conservation nucleus belonging to Brazilian Agricultural Research Corporation - EMBRAPA as well as others flocks present in the region. The results indicated that the total genetic variability of the Fronteira breed and the ecotype Serrana is not represented in the EMBRAPA’s flock nor in the others sampled flocks. The animals kept by EMBRAPA presented a higher introgression of Corriedale than that of the external population. In all analyses the Zebua ecotype was the most dissimilar among the Creoles

A census and phenotypic characterization of Brazilian naturalized genetic swine groups living in the State of Paraíba

The objective of the present work was to carry out a census of the remaining native genetic groups of swine found in the state of Paraíba. A questionnaire was used to identify the breeds by means of their main descriptive factors (hair color, hair presence, ear type, and silhouette). Of all places visited, only thirty-nine had native swine, totalizing 56 animals, among which the Piau breed represented 28.57% of the total evaluated. Other identified breeds were Mouro (n=8; 14.29%), Baé (n=4; 7.14%), and Canastrão (n=2; 3.57%). The largest group of evaluated animals (n=26; 46.42%) comprised those classified as undefined breed. This is indicative of the accelerated genetic dilution process to which these animals are submitted, as a result of disorderly crossings among themselves and with exotic breeds introduced from other countries, available in that region