El consumo de alimento y características de calidad de canal no han podido ser incluidas en programas de mejora genética a pesar de su relevancia económica debido a la dificultad y alto costo de medición. La selección genómica surge como una oportunidad para mejorar estas características. El objetivo de este proyecto es el establecimiento de una población de entrenamiento conformada por 1000 animales entre toros y novillos Hereford.

ABSTRACT: The aim of the paper was to prove the accuracy of various statistical models of variance analysis for estimation of systematic factors that influence milk yield and fat and protein content in dairy goats. Data on daily milk production recorded by methods AT, AC or A4 for the population of Czech White Shorthaired Goats over 1992?2002 was used for calculations. A total of 78 736 test day from 6 234 goats were analysed. Average daily milk production was 3.09 kg with 3.72% of fat and 2.84% of protein.

ABSTRACT. The aim of this study was to investigate the genetic diversity within and among three breeds of sheep:Corriedale, Merino and Creole. Sheep from the three breeds (Merino n = 110, Corriedale n = 108 and Creole n = 10) were genotyped using the Illumina Ovine SNP50 beadchip® . Genetic diversity was evaluated by comparing the minor allele frequency (MAF) among breeds. Population structure and genetic differentiation were assessed using STRUCTURE software, principal component analysis (PCA) and fixation index (FST).

ABSTRACT. The objective of this study was to evaluate the influence of sire breed (Polwarth=P, Poll Dorset=PD and East Friesian=EF) on growth, carcass and meat quality traits of lambs born to wool type ewes. A flock of multiparous Polwarth ewes was mated with connected P, EF and PD rams during three consecutive years. PD cross lambs had higher weaning, slaughtering and carcass weight and growth from birth to weaning and from weaning to slaughtering compared to the other biotypes evaluated.

ABSTRACT. Accurate and cost-effective DNA-based parentage assignment tools are relevant for genetic im-provement and conservation programs. Parentage-testing SNPs selected in commercial sheep breeds were evaluated in Creole sheep in Uruguay using information provided by the 600k SNP chip. Genotyping results indicated a high proportion of fixed and rare SNPs (21.98%; MAF=0.3). Nevertheless, subsets of 72 and 93 SNPs of the most informative markers for parentage testing, reached probability exclusions of 0.9999 and 0.99999, with average MAF values of 0.43.

ABSTRACT. Due to the relevance of carcass and meat quality traits as breeding objectives of Texel as sire terminal breed, a progeny testing was implemented. In general, these difficult to measure traits have received less attention despite their economic relevance, particularly in more extensive environments in which sheep production is mainly located.