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Despite the growing diffusion of cosmopolite specialized breeds, several autochthonous cattle breeds and populations are still bred in Italy. The aim of this study was to provide a high-resolution picture of the genome-wide diversity and population structure of Italian local cattle breeds using medium-density genome-wide SNP markers. After data editing, the dataset included 800 samples from 32 breeds that were genotyped for 31 013 SNPs. For several breeds we observed a low level of polymorphism and genetic diversity, that together with the small effective population sizes confirmed threat of extinction. According to the runs of homozygosity analysis, evidence of recent inbreeding was strong in some breeds. Low pair-wise genetic differentiation values, shared ancestry, admixture events, and reticulations observed on the phylogenetic tree between some breeds, all suggest high levels of gene flow. Clear clusters and relationships between breeds that originated from the same region or area were detected. However, in spite the complex admixture history of most breeds, many of the local Italian cattle breeds have retained unique identities and are differentiated breeds, and this can be due to differences in the origin, differences in climate, genetic isolation and inbreeding. This study represents the first exhaustive analysis of Italian cattle diversity. The results largely agreed with the breeding history of the Italian cattle breeds. The population structure and the low genetic diversity presented here for several breeds should be useful in creating conservation strategies. If reproductive isolation within groups of the same herd and area is maintained in subsequent generations, the short-term rate of inbreeding will increase dangerously, resulting in a decrease in the effective population size and seriously damaging the breeds future. Thus, efforts should be made to improve genetic diversity in these breeds. In particular, mating decisions will play an important role in limiting inbreeding and will increase the size of these local breeds.

Similarly to other species of ruminants, the river buffalo (2n=50) is characterized by the presence of all four casein fractions (??S1, ??, ??S2, and ??) encoded by the four linked autosomal genes (CSN1S1, CSN2, CSN1S2, and CSN3, respectively) mapped on chromosome 7. In particular, the CSN1S1 gene is characterized by an extremely split architecture with 19 exons, many of which of small size (24 bp). It encodes for a precursor of 214 amino acids with a signal peptide of 15 amino acid residues. In recent years, several polymorphisms at milk protein loci associated with traits of economic interest like milk coagulation properties or milk composition have been intensified. Despite that, so far, not any SNP within the milk protein loci was found to be associated with an important trait like milk yield. The aim of this study was to evaluate possible effects of the SNP c.628C>T, identified at position 89 of 17th exon of the CSN1S1 gene and responsible for the amino acid change p.Ser178Leu (A and B allele, respectively) (EMBL n° HE573919-20), on milk yield in Italian Mediterranean river buffaloes. A total of 7547 records for milk yield measured monthly on 1096 lactations of 552 buffaloes belonging to different farms located in Salerno and Caserta province (Southern Italy) were analyzed. Sampling and phenotypic collection data were carried out in collaboration with the Italian National Association of Buffalo Breeders (ANASB). The genotyping of examined animals was carried out by a method based on MboI-ACRS. The major allele (B) had a relative frequency of about 0.6 and ??2 values showed that there was no evidence of departure from the Hardy-Weinberg equilibrium (P???0.05). Association between CSN1S1 polymorphism and milk yield was investigated with a mixed linear model that included effects of parity, calving season and month of production. A significant association between the SNP c.628C>T and milk yield was found (P

The aim of the present study was to investigate the variability at CSN1S1 locus of the Italian Mediterranean river buffalo and to study possible allele effects on milk yield and its composition. Effects of parity, calving season and month of production were also evaluated. Three single-nucleotide polymorphisms were detected. The first mutation, located at position 89 of the 17th exon (c.628C>T), is responsible for the amino acid change p.Ser178 (B allele)/Leu178 (A allele). The other two polymorphisms, detected at the positions 144 (c.882G>A) and 239 (c.977A>G) of 19th exon, respectively, are silent (3ʹ UTR, untranslated region). Associations between the CSN1S1 genotypes and milk production traits were investigated using 4122 test day records of 503 lactations from 175 buffalo cows. Milk yield, fat and protein percentages were analysed using a mixed linear model. A significant association between the c.628C>T SNP and the protein percentage was found. In particular, the CC genotype showed an average value ~0.04% higher than the CT and TT genotypes. The allele substitution effect of cytosine into thymine was –0.014, with a quite low (0.3%) protein percentage contribution to total phenotypic variance. A large dominance effect was detected. Characterisation of the CSN1S1 transcripts and a method based on MboI amplification created restriction site PCR for a rapid genotyping of c.628C>T are provided.

L'agricoltura moderna sta attraversando un'importante fase di transizione che la porterà ad acquisire un nuovo ruolo nel contesto socio-economico nazionale e internazionale. La zootecnia italiana, dal canto suo si sta adeguando alle nuove esigenze del settore, grazie anche all'apporto della ricerca scientifica. Tra i settori della ricerca a più alto impatto nel campo zootecnico, la ricerca genetica, con le nuove tecnologie e approcci che derivano dal miglioramento delle conoscenze nel trattamento dei dati quantitativi e dall'analisi del genoma degli animali, sta portando a importanti cambiamenti nella selezione animale. In questa introduzione si fa il punto sullo stato dell'arte del miglioramento genetico animale aprendo una finestra sulle prospettive future.

Su 9 puledri asinini sardi (4 maschi e 5 femmine), sottoposti a ingrassamento con paglia e concentrato per 4 mesi, sono stati effettuati i rilievi alla macellazione e lo spolpo completo della mezzena sinistra; su 6 (3 maschi e 3 femmine) sono state valutate le caratteristiche reologiche delle carni (durezza, coesione, resilienza elastica, adesione, masticabilità, acqua liberata totale). La resa in carcassa sul peso vivo stallato è risultata del 56,47%, quella del quinto quarto del 33,42%, l'incidenza del contenuto dell'apparato digerente del 10,11%; la resa in carcassa sul peso netto è stata del 62,83% e quella delle singole parti del quinto quarto è stata del 6,23% per la testa, del 9,71% per la pelle, del 2,66% per le parti distali degli arti, del 2,57% per la corata, dell'1,66% per il fegato e dello 0,43% per la milza. La carcassa è risultata composta per il 62,57% da muscolo, per il 15,58% da grasso separabile e per il 21,85% da ossa + tendini; la sua lunghezza è stata di cm 89, la lunghezza e la larghezza della coscia di cm 55 e 14 rispettivamente. Per quanto riguarda le caratteristiche reologiche delle carni, il sesso si è rivelato una importante fonte di variazione soprattutto per la durezza e per l'acqua liberata, il tipo di muscolo per tutte le caratteristiche considerate, a eccezione della resilienza elastica. Le femmine hanno fornito mediamente una carne piú tenera, piú masticabile e con un maggior potere di ritenzione idrica; il muscolo qualitativamente migliore è risultato lo psoas major, quello peggiore il vastus lateralis.