Search results for "miglioramento genetico"
showing 10 items of 211 documents
Variation of proteomic profile during lactation in Girgentana goat milk: a preliminary study
2019
The knowledge of milk proteome has been greatly enhanced by technological advances in the proteomics field as the use of the two-dimensional differential in-gel electrophoresis, a gel-based approach which allowed the analysis of proteins from complex mixtures and the comparing of several protein samples in the same experiment. The aim of this study was to characterise the whole milk proteomic profile in Girgentana dairy goat breed by two-dimensional differential in-gel elecrophoresis. The obtained representative 2D whole milk proteomic map showed a general picture of the protein distributions over the pH 3–10 NL including about 100 spots, most of them organised like a spot train. Among diff…
Determination of protein content and fatty acid profile in milk of Girgentana goat breed for evaluation of nutritional characteristics of dairy produ…
2014
I geni delle caseine caprine mostrano un elevato polimorfismo, che influenza non solo la quantità di caseine nel latte ma anche le caratteristiche strutturali e nutrizionali e le proprietà tecnologiche del latte. Uno degli obiettivi di questa tesi è stato quello di separare e quantificare le più comuni varianti alleliche caseiniche nel latte di capra di razza Girgentana, una razza autoctona siciliana, e di valutare l’effetto dei polimorfismi caseinici sul contenuto di caseina nel latte. I genotipi e, quindi, gli alleli ai diversi geni delle caseine sono stati rilevati utilizzando protocolli di PCR, PCR-RFLP, AS-PCR e analisi di sequenziamento. I campioni di latte sono stati preparati seguen…
Meta-Analysis of Mitochondrial DNA Reveals Several Population Bottlenecks during Worldwide Migrations of Cattle
2014
Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle have shifted the haplogroup distributions considerably with a reduction of the number of haplogroups and/or an expansion of haplotypes that are rare or absent in the ancestral populations. The most extreme case is the almost exclusive colonization of Africa by the T1 haplogroup, which is rare in Southwest Asian cattle. In contrast, ancient samples invariably show continuity with present-day cattle …
Development of "Quadrello di Ovino", a Novel Fresh Ewe's Cheese.
2021
This work was performed to produce a new soft ewe’s milk cheese, namely “Quadrello di ovino” (QdO) cheese, to enlarge ewe’s dairy product portfolio of South Italy, barely limited to Pecorino cheese typology. Cheese making was performed applying the technology for “Crescenza” cheese typology with some modifications. In particular, pasteurized ewes’ milk was inoculated with two commercial starter formulations (SF1 and SF2) of Streptococcus thermophilus to obtain two different productions (QdO-P1 and QdO-P2, respectively). Plate counts demonstrated the ability of both starter formulations to drive the fermentation process, since S. thermophilus counts reached 109 CFU/g in both productions. Gen…
Genome wide linkage disequilibrium and genetic structure in Sicilian dairy sheep breeds
2014
Background The recent availability of sheep genome-wide SNP panels allows providing background information concerning genome structure in domestic animals. The aim of this work was to investigate the patterns of linkage disequilibrium (LD), the genetic diversity and population structure in Valle del Belice, Comisana, and Pinzirita dairy sheep breeds using the Illumina Ovine SNP50K Genotyping array. Results Average r2 between adjacent SNPs across all chromosomes was 0.155 ± 0.204 for Valle del Belice, 0.156 ± 0.208 for Comisana, and 0.128 ± 0.188 for Pinzirita breeds, and some variations in LD value across chromosomes were observed, in particular for Valle del Belice and Comisana breeds. Ave…
Analysis of the influence of the PrP genotype on the litter size in Polish sheep using classification trees and logistic regression
2014
The relation between prion protein (PrP) genotype class and litter size was analysed in Polish Merino, Black-headed, Ile de France and Berrichon du Cher sheep in Poland. Litter size was analysed with the classification tree technique and multiple logistic regression for effects of breed, age of ewe, PrP genotype, litter size of ewe at her birth, and at her rearing and year of ewe's birth. The resulting classification tree was 6-level deep and contained 21 leaves. Age, breed and year of birth were more important determinants of litter size than PrP genotype. Importance of PrP genotype in the tree development was 0.560 relative to age of ewe. While the logistic regression analysis showed that…
Estimation of genetic and phenotypic parameters for bacteriological status of the udder,somatic cell score,and milk yield in dairy sheep using a thre…
2013
Abstract The objective of this study was to estimate the genetic parameters for infection status (INF), as indicator of mastitis, SCS (i.e., log-transformed SCC), and milk yield (MY), by using a Gibbs sampling algorithm. The data comprised 17,843 test-day records of 2040 ewes. The pedigree file included 2948 animals. A bivariate variance component analysis was performed using the TM software. Fixed effects considered in the analysis were litter size, parity, flock by test-day interaction, year by season of lambing interaction, and stage of lactation; whereas the animal, and the permanent environmental effect within and across lactations were considered as random as well as the error. Flat p…
Genome-wide identification of runs of homozygosity islands and associated genes in local dairy cattle breeds
2018
Runs of homozygosity (ROH) are widely used as predictors of whole-genome inbreeding levels in cattle. They identify regions that have an unfavorable effect on a phenotype when homozygous, but also identify the genes associated with traits of economic interest present in these regions. Here, the distribution of ROH islands and enriched genes within these regions in four dairy cattle breeds were investigated. Cinisara (71), Modicana (72), Reggiana (168) and Italian Holstein (96) individuals were genotyped using the 50K v2 Illumina BeadChip. The genomic regions most commonly associated with ROHs were identified by selecting the top 1% of the single nucleotide polymorphisms (SNPs) most commonly…
Genome-wide analysis in endangered populations: a case study in Barbaresca sheep
2017
Analysis of genomic data is becoming increasingly common in the livestock industry and the findings have been an invaluable resource for effective management of breeding programs in small and endangered populations. In this paper, with the goal of highlighting the potential of genomic analysis for small and endangered populations, genome-wide levels of linkage disequilibrium, measured as the squared correlation coefficient of allele frequencies at a pair of loci, effective population size, runs of homozygosity (ROH) and genetic diversity parameters, were estimated in Barbaresca sheep using Illumina OvineSNP50K array data. Moreover, the breed's genetic structure and its relationship with oth…
On the origin of European sheep as revealed by the diversity of the Balkan breeds and by optimizing population-genetic analysis tools
2020
Background In the Neolithic, domestic sheep migrated into Europe and subsequently spread in westerly and northwesterly directions. Reconstruction of these migrations and subsequent genetic events requires a more detailed characterization of the current phylogeographic differentiation. Results We collected 50 K single nucleotide polymorphism (SNP) profiles of Balkan sheep that are currently found near the major Neolithic point of entry into Europe, and combined these data with published genotypes from southwest-Asian, Mediterranean, central-European and north-European sheep and from Asian and European mouflons. We detected clines, ancestral components and admixture by using variants of commo…