Novel genetic polymorphisms associated with carcass traits in grazing Texel sheep.

Improving meat production traits has increased its importance in sheep breeding. We report novel associations of SNP present in genes related to lipid metabolism and growth with several carcass traits in purebred Texel lambs. Expected progeny differences (EPD) predictions from 461 animals from the Central Progeny Testing of Texel breed in Uruguay were used for the association analysis.

Genetic diversity analysis of the Uruguayan Creole cattle breed using microsatellites and mtDNA markers.

The Uruguayan Creole cattle population (N = 600) is located in a native habitat in south-east Uruguay. We analyzed its genetic diversity and compared it to other populations of American Creole cattle. A random sample of 64 animals was genotyped for a set of 17 microsatellite loci, and the D-loop hyper-variable region of mtDNA was sequenced for 28 calves of the same generation.

Genetic footprints of Iberian cattle in America 500 years after the arrival of Columbus.

Background: American Creole cattle presumably descend from animals imported from the Iberian Peninsula during the period of colonization and settlement, through different migration routes, and may have also suffered the influence of cattle directly imported from Africa. The introduction of European cattle, which began in the 18th century, and later of Zebu from India, has threatened the survival of Creole populations, some of which have nearly disappeared or were admixed with exotic breeds. Assessment of the genetic status of Creole cattle is essential for the establishment of conservation programs of these historical resources.

Genetic characterization of Latin-American Creole cattle using microsatellite markers.

Genetic diversity in and relationships among 26 Creole cattle breeds from 10 American countries were assessed using 19 microsatellites. Heterozygosities, F-statistics estimates, genetic distances, multivariate analyses and assignment tests were performed. The levels of within-breed diversity detected in Creole cattle were considerable and higher than those previously reported for European breeds, but similar to those found in other Latin American breeds.

Sex chromosomes behavior and G-banding treatment of male meiosis in nuptial gift-giving spiders of the family Trechaleidae.

Preliminary genetic studies in Trechaleidae spider family show high variation in sex chromosomes and high heterocigocity, suggesting high chromatin plasticity. The trechaleids Paratrechalea ornata, Trechalea bucculenta and Trechaleoides biocellata are present in Uruguay. Males offering nuptial gifts during courtship have been reported in P.