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A total of 4466 monthly test day records of 555 Greek Sfakia dairy ewes were used to estimate heritabilities as well as genetic and phenotypic correlations for udder score (US), average daily milk yield (MY), fat percentage (FC) and protein percentage (PC) of milk. Genetic parameters were estimated with a multitrait animal model with correlated residuals. Heritabilities were between 0.17 and 0.24, 0.41 and 0.47, 0.32 and 0.52 and 0.44 and 0.55, for test day US, MY, FC and PC, respectively. Within traits, genetic correlations between test days were between 0.54 and 0.57, 0.71 and 0.96, 0.79 and 0.99 and 0.85 and 0.99 for US, MY, FC and PC, respectively. Genetic correlations between milk traits and US were negative and of very low magnitude (−0.04 to −0.06). Genetic correlations between MY – FC and MY – PC were negative and of varying magnitude, from −0.37 to −0.52 and from −0.44 to −0.50, in the four test days, respectively. Fat and protein percentages were found to be highly, positively, correlated.

In the present work an attempt to apply graph analysis on visual representations of animals' pedigrees is presented. Analysis of pedigree networks of moderate size (tens or hundreds of points) can substantially contribute to revealing the relational structures between animals. Partitioning graphic representations of pedigree networks to smaller parts (blocks) by means of network decomposition methods resulted in better handling and understanding of horse genealogical data. Analysis of pedigree networks could be used to estimate shortest kinship paths among animals, determinate all predecessors and successors of selected animals and finally to estimate inbreeding coefficients of selected individuals. Detection of families and animals with major gene contribution could substantially be facilitated. Graphic representation of pedigree networks provide simultaneous, dynamic and parsimonious representation of kinship, interrelations and constituent structures.

Production and reproduetive traits in Danish Landrace (LD) and Large White (LW) swine were analysed by restricted maximum likelihood methods to obtain heritabilities as well as genetic and phenotypic correlations. Production traits were: age, backfat thickness (BT), muscle depth (MD) and the ratio BT/MD, adjusted to Standard bodyweight of 85 kg. Reproduction traits were: number of pigs born (NB) and number of pigs weaned (NW) per sow and parity. Heritabilities for age, BT, MD and BT/MD were 0.60, 0.44, 0.51 and 0.42 for LD and 0.36, 0.44, 0.37 and 0.45 for LW, respectively. Genetic correlations between age and BT were −0.22 in LD and – 0.44 in LW. The genetic correlation between age and MD was close to zero in both breeds. Genetic correlation between BT and MD were −0.36 and −0.25 in LD and LW, respectively. Heritabilities for NB were 0.25 in LD and 0.13 in LW while heritabilities for NW were close to zero in both breeds. Genetic correlation between NB and NW was 0.46 and 0.70 in LD and LW, respectively.