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Italian Maremmana, Turkish Grey and Hungarian Grey breeds belong to the same Podolic group of cattle, have a similar conformation and recently experienced a similar demographic reduction. The aim of this study was to assess the relationship among the analysed Podolic breeds and to verify whether their genetic state reflects their history. To do so, approximately 100 single nucleotide polymorphisms (SNPs) were genotyped on individuals belonging to these breeds and compared to genotypes of individuals of two Italian beef breeds, Marchigiana and Piemontese, which underwent different selection and migration histories. Population genetic parameters such as allelic frequencies and heterozygosity values were assessed, genetic distances calculated and assignment test performed to evaluate the possibility of recent admixture between the populations. The data show that the physical similarity among the Podolic breeds examined, and particularly between Hungarian Grey and Maremmana cattle that experienced admixture in the recent past, is mainly morphological. The assignment of individuals from genotype data was achieved using Bayesian inference, confirming that the set of chosen SNPs is able to distinguish among the breeds and that the breeds are genetically distinct. Individuals of Turkish Grey breed were clearly assigned to their breed of origin for all clustering alternatives, showing that this breed can be differentiated from the others on the basis of the allelic frequencies. Remarkably, in the Turkish Grey there were differences observed between the population of Enez district, where in situ conservation studies are practised, and that of Bandirma district of Balikesir, where ex situ conservation studies are practised out of the original raising area. In conclusion, this study demonstrates that molecular data could be used to reveal an unbiased view of past events and provide the basis for a rational exploitation of livestock, suggesting appropriate cross-breeding plans based on genetic distance or breeding strategies that include the population structure. [ABSTRACT FROM AUTHOR]

A set of 11 polymorphic microsatellites has been used to assess the distribution of genetic variability in 17 flocks of the Sarda sheep breed in the Viterbo province, located in central Italy. The suitability of samples size and number of loci analysed were tested using a bootstrap procedure. The data obtained were used to estimate the genetic diversity within and among flocks, and to test the presence of inbreeding within flocks. To study the genetic relationship among flocks, a principal component analysis based on Nei standard distances was performed. The results of genetic analysis show a significant excess of homozygotes in some of the flocks. The use of genetic data for maximum likelihood tests of assignment is investigated in order to establish suitable breeding policies. This research represents a case study for the development of mating strategies suitable for incrementing genetic variability within flocks that can be applied in other domestic species showing similar breeding problems (goat, buffalo and small populations of cattle). [ABSTRACT FROM AUTHOR]