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The Podolica cattle breed is autochthonous of Southern Italy and denoted by its particular rusticity. This study presents the preliminary results of the genetic characterization of the Podolica breed using DNA STR markers. A total of 20 microsatellite loci were analysed in 79 individuals reared in the Gargano area. Number of polymorphisms, allele fre- quencies, deviations from Hardy-Weinberg proportions, linkage disequilibrium between loci and genetic similarities between animals were calculated. The results showed a high deficiency of heterozygotes, the observed mean of het- erozygosis being 0.449, whereas the expected mean was 0.766. Many markers showed also deviations from the Hardy- Weinberg proportions and significant linkage disequilibrium between loci. However the genetic similarity within the pop- ulation was low (0.281) and the average number of alleles per locus was high (10), representing a high genetic vari- ability. In order to explain these results, a stratification of the breed in sub-populations with a high interior genetic homo- geneity but markedly differentiated one from each other could be hypothesized; this situation probably derived from non- random mating within each herd (consanguinity) and from the lack of exchange of genetic material between the herds. A further study is needed on a wider sample and extending the analysis to FAO-ISAG microsatellite panel in order to con- firm this hypothesis. This could eventually provide the information necessary for the correct management of the repro- ductive schemes and for genomic traceability of meat production.

The heritability of quality traits (chemical composition, colour, tenderness and water-holding capacity) of the meat derivingfrom three muscles (Triceps brachii, Longissimus dorsi and Semitendinosus) was evaluated in 92 young Chianinabulls. The animals were raised on two farms with different feeding programs, and were slaughtered at approximately 19months of age. Single pair correlations were considered in order to evidence the relationships between the same traitsdetected in the three muscles and between all the traits of the same muscle.The h2 values range from 0.00 to 0.24 for the chemical composition, from 0.00 to 0.19 for colour parameters, from 0.03to 0.31 for those observed after 48 h, and from 0.00 to 0.08 for tenderness and water-holding capacity. The values werenot homogeneous for the three muscles. The most heritable trait was yellowness (b*48) in all three muscles, with valuesof 0.11 in the Longissimus dorsi, 0.23 in the Semitendinosus, and 0.31 in the Triceps brachii. Conversely, tendernessappeared to have a low heritability, as did the parameters relating to the water-holding capacity. Colour traitsobserved before and after 48 h of storage generally were significantly and positively correlated, indicating that certaincolour characteristics are maintained even after 48 h of storage. There was not always a close relationship between thetraits of each muscles: significant correlations existed between the Triceps brachii and the Longissimus dorsi muscles,confirming the similar quality traits of their meat, while there were considerable differences between these muscles andthe Semitendinosus.

Italy has a long history of sheep breeding and, despite a dramatic number contraction occurred in the last century, still counts several local sheep breeds that may represent a unique source of genetic diversity. Here we present the results from the genetic characterization of seven Italian dairy sheep breeds by 19 STR markers. High levels of polymorphism were generally detected, with 16.2 average alleles per locus and an average gene diversity of 0.79. The within-breed analysis highlighted, in six out of the seven breeds, a remarkable proportion of loci displaying significant heterozygote deficit. Moreover, within-breed percentages of locus pairs with significant genotypic disequilibrium were, for all breeds, markedly higher than expected by chance thus suggesting the presence of population stratification. The subdivision was particularly evident for the Leccese sheep breed and was confirmed by the STRUCTURE analysis. On the contrary, results generally highlighted Sarda as the most homogeneous, but less inbred, population, consistently with its large census size and longstanding effective genetic management practices. Both STRUCTURE analysis and measures of genetic distance, with the exception of those based on allele sharing, suggested the presence of a phylogeographic gradient, with Sarda as the most differentiated breed and continental breeds from the same region tending to group closer to each other.Taken together, the results highlighted that all the Italian breeds display a genetic variability content comparable to other European breeds, thus demonstrating their importance as genetic reservoir for future selection options. However, management actions should be more effectively implemented in local endangered breeds in order to reduce inbreeding and within-breed sub-structuring.

We investigated the genetic variability within and between cattle breeds. The polymorphisms of 17 microsatellites were studied in 220 unrelated animals belonging to four Italian beef cattle breeds (Chianina, Marchigiana, Romagnola, and Piemontese). Variations of allelic frequencies were examined to characterize the breeds and their relationships. Wahlund coefficients, Polymorphism Information Content values, and Haldane exact test for Hardy-Weinberg proportions were calculated. The results show that the Hardy-Weinberg equilibrium is not always maintained. Moreover, in addition to the classical genetic distances, a new method, based on the consideration of a multilocus genotype of each animal, was set up to measure the genetic similarity between animals or within groups of animals. All the results showed that, whereas Chianina occupies an intermediate position and Piemontese is the most distinct of all four breeds, Marchigiana and Romagnola display the strongest similarity. The new method also provides evidence that average similarities are always higher within breeds than between breeds. By comparing pairwise the multilocus genotypes, it was also possible to discriminate the individuals with higher or lower genetic similarities so that each breed could be subdivided into two groups of animals in relation to their similarity to the average breed multilocus genotype. High similarities between breeds were detected, somewhat surprisingly, when the most homogeneous groups of each breed were compared. The microsatellite multilocus genotype is particularly efficient in evaluating the between- and within-breeds genetic similarities and for subgrouping genetically more homogeneous animals.

The dramatic size contraction of local cattle breeds due to replacement with cosmopolite improved breeds highlights the need for native genetic resources conservation. In 1985, the Anagraphic Register of local cattle breeds and small-size ethnic groups was established by the Italian Ministry of Agriculture and Forestry. Calvana, Pontremolese and Garfagnina are among the included breeds. They are all native from Tuscany. Present breeding area covers the provinces of Firenze, Prato, Pistoia and Siena for the Calvana breed (around 280 heads), while it is restricted to the province of Lucca for both Garfagnina (around 180 heads) and Pontremolese. This latter breed consists, nowadays, of less than 40 heads, while being around 15000 in 1940s.The characterization of the genetic structure and variability via molecular markers could provide useful information for breed management and conservation. In the present study, a total of 149 animals, evenly distributed among the three breeds, were genetically char...

To elaborate a methodological approach for the assignment of a breed to a carcass or other animal tissue, DNA microsatellites were utilized. Four Italian beef breeds were studied; examining these breeds is a challenge because they display similar morphological and productive characteristics. As comparison 54 Holstein–Friesian subjects were used. To measure the genetic similarities between animals or between groups of animals we used our method (Ciampolini et al, 1995, Individual multilocus genotypes using microsatellite polymorphisms to permit the analysis of the genetic variability within and between italian beef cattle breeds. Journal of Animal science,73 , 3259-3268.) based on the consideration of a multilocus genotype of each animal, which enabled us to establish breed genomic formulae. Although the results are only preliminary, they show that we can distinguish easily between Holstein–Friesian subjects and beef animals; moreover we can identify, with a high resolution potential, animals from breeds (the four Italian white) with very high genetic similarities. However all the Holstein–Friesian subjects were identified.