Search results for "breed"
showing 10 items of 697 documents
LINKAGE DISEQUILIBRIUM AND GENETIC DIVERSITY IN TWO SICILIAN CATTLE BREEDS ASSESSED BY BOVINE SNP CHIP
2013
The Modicana (MOD) and Cinisara (CIN) are two Sicilian cattle breeds farmed in extensive systems and their economic importance lies on the traditional making of two typical ‘pasta filata’ cheeses. The aim of this study was to explore the genetic structure and the extent of Linkage Disequilibrium (LD) of MOD and CIN cattle breeds. A total of 144 animals were genotyped, using the Bovine SNP50K v2 BeadChip. The squared correlation coefficient between two loci (r2) was used as a measure of LD. Principal components analysis (PCA), molecular inbreeding (F) and Bayesian clustering algorithm (Pritchard et al., 2000) were used to explore the relationship between individuals and populations. The r2 r…
Using of SNP markers to estimate inbreeding, coancestry and effective population size in Sicilian cattle breeds
2014
Maintaining the highest levels of genetic diversity and limiting the increase in inbreeding is the premise of most conservation programs. The aim of this work was to estimate the inbreeding (F), coancestry (f) and effective population size (Ne) in two Sicilian cattle breeds, Cinisara (CIN) and Modicana (MOD). Rate of molecular inbreeding and coancestry were used to estimate the Ne. A total of 144 animals were genotyped using the Illumina Bovine SNP50K v2 BeadChip. The average molecular F and f coefficients were 0.68±0.024 and 0.67±0.03 in CIN and 0.69±0.020 and 0.70±0.03 in MOD cattle breeds, respectively. The results were not unexpected considering the reduced number of reared animals and …
Linkage disequilibrium and genetic diversity estimation in three Sicilian autochthonous dairy sheep breeds
2014
Understanding genetic structure is essential for achieving genetic improvement through genome-wide association studies, genomic selection and the dissection of quantitative traits. In the present study, we used the OvineSNP50K BeadChip to characterize LD, identify haplotype blocks and to analyze genetic diversity in the Valle del Belice (VDB), Comisana (COM) and Pinzirita (PIN) dairy sheep breeds. LD between adjacent SNPs and for all pairwise combinations of SNPs on each chromosome was measured using r2. Haplotype blocks were estimated using D’ based method. Genetic diversity and Principal Component Analysis (PCA) were calculated using PLINK. Small differences in average LD value for adjace…
Genetic structure and assignment test in five sheep breeds reared in Sicily using microsatellites
2011
A total of 331 individuals from five sheep breeds reared in Sicily (Barbaresca (BAR, n=57), Comisana (COM, n=65), Pinzirita (PIN, n=75), Sarda (SAR, n=64), and Valle del Belice (VdB, n=70)) were analysed to investigate genetic structure and perform an assignment test. A panel of 20 microsatellite markers was used, and a total of 259 alleles were observed. The polymorphic information content (PIC) all over loci was equal to 0.757, showing that the microsatellites panel used was highly informative. Estimates of observed heterozygosity ranged from 0.655 in the BAR breed to 0.751 in the COM breed. The low value of genetic differentiation among breeds (FST=0.048) may indicate that these breeds a…
Use of microsatellite markers for genetic traceability of Girgentana dairy products
2015
Genetic traceability is based on the identification of both animals and their products through the study of DNA. With the goal of developing a genetic traceability system for dairy products, the aim of this study was to identify specific microsatellite markers able to discriminate among the most important Sicilian dairy goat breeds, in order to detect possible adulteration in Girgentana dairy products. A total of 20 microsatellite markers were analyzed on a total of 338 individual samples from Girgentana (GIR), Maltese (MAL) and Derivate di Siria (DdS) goat breeds. The first step was to identify breed specific microsatellite markers that can be used for the traceability of dairy products. A…
Survey of milk protein polymorphism in the "Bovina Rossa Siciliana"
2005
The “Rossa Siciliana” is an autochthonous small Sicilian dairy cattle population, accounting for 5-7,000 individuals.This breed is characterized by high ability to live on poor pasture lands, moderate milk production, and traditionally linked to cheese production. Aim of this work was to investigate milk protein polymorphisms in this population. A total of 62 individual milk samples were collected from 19 extensive farms spread in the “Parco dei Nebrodi” area (Messina). All samples were analyzed by isoelectrofocusing (IEF) with pH range 2.5-6. High variability was found at the CSN1S1, CSN2, CSN3, LGB and LALBA loci, while the CSN1S2 locus was monomorphic for the A allele. The allele frequen…
Genetic and protein polymorphism at CSN1S1 locus in two goat breeds.
2006
Genetic polymorphisms of casein have received a considerable research effort for many years because of its potential effect on milk composition. Milk composition, specifically protein content, differs quantitatively and qualitatively among species and also among breeds and individuals. Sicilian goat breeds seem to be an interesting model since they have never been under a selection program, and therefore may carry unique casein polymorphisms. Moreover, the importance of goat milk in infant diets is growing probably because goat milk in some cases is less allergenic than cow milk. It is important to evaluate the genetic polymorphisms at the CSN1S1 locus in the populations of interest, like t…
Distribution of functional variants within Runs of Homozygosity in four Italian cattle breeds
2017
Several methods have been used to identify genomic regions subjected to selective sweeps. An alternative method can make use of runs of homozygosity (ROH), defined as stretches of homozygous regions in a genome. The aim of the present study was to detect selective sweeps using ROH in four cattle breeds. Individuals of Cinisara (71), Modicana (72),Reggiana (168) and Italian Holstein (96) were genotyped with the Illumina Bovine50SNP v2 BeadChip. To identify genomic regions that were most commonly associated with ROH within each breed, the percentage of occurrences of a single nucleotide polymorphism (SNP) in ROH was calculated across animals. The genomic regions most commonly associated with …
Analysis of acetyl-CoA carboxylase gene polymorphisms in Valle del Belice dairy breeds
2015
Acetyl-CoA carboxylase is the flux-determining enzyme in the regulation of fatty acid synthesis within animal tissues. The expression of the mammary gland isoform of this enzyme, during lactation, is regulated by the acetyl-CoA carboxylase-α (ACACA) gene. The ovine ACACA gene, with 51 coding exons, is responsible for phenotypic variability observed in milk fat content and milk fatty acids (FAs) composition. However, before attempting association analyses between this enzyme and phenotypic traits of interest, a study on the genetic variability within this locus is required. The aim of this work was to sequence the encoding region of ACACA gene in Valle del Belice dairy ewes in order to ident…
BOVITA: a first overview on genome-wide genetic diversity of Italian autochthonous cattle breeds
2017
Analysis of genomic data is increasingly becoming part of the livestock industry and is an invaluable resource for effective management of breeding programs in small populations. The recent availability of genome-wide SNP panels allows providing background information concerning genome structure in domestic animals, opening new perspectives to livestock genetics. BOVITA was established to join local efforts and resources for the genomic characterization of Italian local cattle breeds. Despite the growing diffusion of some cosmopolite specialized breeds, several autochthonous breeds are still bred in Italy. The main aim of the BOVITA is to investigate the genomic structure of Italian local c…