Genome-wide association study reveals the locus responsible for microtia in Valle del Belice sheep breed.

2018

Microtia is a congenital deformity of the outer ear with phenotypes varying from a small auricle to total absence (anotia). The genetic basis is still poorly understood, and very few studies have been performed in sheep. Valle del Belice sheep is a breed showing microtia. The aim of this study was to identify the potential genomic regions involved in microtia in sheep. A total of 40 individuals, 20 with microtia and 20 normal, were genotyped with the Illumina OvineSNP50 BeadChip. The comparison among the results from a genome-wide association study, Fisher's exact test and FST analysis revealed a single strong association signal: rs419889303 on chromosome 1, located within intron 3 of the C…

Determination of milk production losses and variations of fat and protein percentages according to different levels of somatic cell count in Valle de…

2018

The somatic cell count (SCC) of milk is widely used to monitor udder health and the milk quality and because of its positive genetic correlation with mastitis this trait was included in breeding schemes of dairy sheep. The aim of this study was to estimate the loss in milk yield (MY) and related composition resulting from different levels of somatic cell count in Valle del Belice dairy sheep. Data were collected between 2006 and 2016 in 15 flocks following an A4 recording scheme. Somatic cell count (SCC), fat and protein percentage (F% and P%) were determined using mid-infrared spectroscopy. To evaluate loss in test day MY, F% and P%, five different classes of SCC were arbitrarily defined: …

Genome-wide scan for runs of homozygosity identifies potential candidate genes associated with local adaptation in Valle del Belice sheep

2017

Background Because very large numbers of single nucleotide polymorphisms (SNPs) are now available throughout the genome, they are particularly suitable for the detection of genomic regions where a reduction in heterozygosity has occurred and they offer new opportunities to improve the accuracy of inbreeding (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$F$$\end{document}F) estimates. Runs of homozygosity (ROH) are contiguous lengths of homozygous segments of the genome where the two haplotypes inherited from t…

Genome-Wide Patterns of Homozygosity Reveal the Conservation Status in Five Italian Goat Populations.

2021

The application of genomic technologies has facilitated the assessment of genomic inbreeding based on single nucleotide polymorphisms (SNPs). In this study, we computed several runs of homozygosity (ROH) parameters to investigate the patterns of homozygosity using Illumina Goat SNP50 in five Italian local populations: Argentata dell’Etna (N = 48), Derivata di Siria (N = 32), Girgentana (N = 59), Maltese (N = 16) and Messinese (N = 22). The ROH results showed well-defined differences among the populations. A total of 3687 ROH segments &gt

Genome-wide association study between CNVs and milk production traits in Valle del Belice sheep.

2019

Copy number variation (CNV) is a major source of genomic structural variation. The aim of this study was to detect genomic CNV regions (CNVR) in Valle del Belice dairy sheep population and to identify those affecting milk production traits. The GO analysis identified possible candidate genes and pathways related to the selected traits. We identified CNVs in 416 individuals genotyped using the Illumina OvineSNP50 BeadChip array. The CNV association using a correlation-trend test model was examined with the Golden Helix SVS 8.7.0 tool. Significant CNVs were detected when their adjusted p-value was <0.01 after false discovery rate (FDR) correction. We identified 7,208 CNVs, which gave 365 C…

Genome-wide association studies for milk production traits in Valle del Belice sheep using repeated measures

2019

Genome-wide association studies (GWASes) have become a powerful tool for identifying genomic regions associated with important traits in livestock. Milk production traits in dairy sheep are measured at different time points during their life span. Using phenotypic data generated from longitudinal traits could improve the power of association studies but until now have received less attention in GWASes as a methodology and has not been implemented. The aim of this study was to carry out a GWAS for milk production traits in Valle del Belice sheep using repeated measures. After quality control, 469 ewes and 37 228 SNPs were retained for the analysis, and phenotypic data included 5586 test-day …

Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Indust…

2021

Red grape Nero d’Avola cultivar grape pomace powder (GPP) was applied during fresh ovine cheese production in order to increase polyphenol content. Before cheeses were produced, the bacteria of a freeze-dried commercial starter culture were isolated and tested in vitro against GPP. Two dominant strains, both resistant to GPP, were identified. Thestarter culture was inoculated in pasteurized ewe’s milk and the curd was divided into two bulks, one added with 1% (w/w) GPP and another one GPP-free. GPP did not influence the starter culture development, since lactic acid bacteria (LAB) counts were 109 CFU/g in both cheeses at 30 d. To exclude the interference of indigenous LAB, the pasteurized m…

Genomic structural diversity in local goats: Analysis of copy-number variations

2020

Copy-number variations (CNVs) are one of the widely dispersed forms of structural variations in mammalian genomes, and are present as deletions, insertions, or duplications. Only few studies have been conducted in goats on CNVs derived from SNP array data, and many local breeds still remain uncharacterized, e.g., the Sicilian goat dairy breeds. In this study, CNV detection was performed, starting from the genotypic data of 120 individuals, belonging to four local breeds (Argentata dell&rsquo

Identification of Copy Number Variations and Genetic Diversity in Italian Insular Sheep Breeds

2022

Simple Summary The aim of this work is to identify CNVs and perform a CNV-based population genetics analysis in five Italian sheep breeds (Barbaresca, Comisana, Pinzirita, Sarda, and Valle del Belìce). We identified 10,207 CNVs and 365 CNV regions (CNVRs). The different approaches used to disclose the genetic relationship showed that the five breeds tend to cluster in distinct groups. Gene enrichment was described for the 37 CNVRs selected considering the top 10%. Gene Ontology analysis showed that several of these genes are involved in lipid metabolism, immune response, and the olfactory pathway. CNVs represent valuable molecular resources to provide useful information for separating the p…

Genome-wide detection of copy-number variations in local cattle breeds

2019

The aim of the present study was to identify copy-number variations (CNVs) in Cinisara (CIN) and Modicana (MOD) cattle breeds on the basis of signal intensity (logR ratio) and B allele frequency of each marker, using Illumina’s BovineSNP50K Genotyping BeadChip. The CNVs were detected with the PennCNV and SVS 8.7.0 software and were aggregated into CNV regions (CNVRs). PennCNV identified 487 CNVs in CIN that aggregated into 86 CNVRs, and 424 CNVs in MOD that aggregated into 81 CNVRs. SVS identified a total of 207 CNVs in CIN that aggregated into 39 CNVRs, and 181 CNVs in MOD that aggregated into 41 CNVRs. The CNVRs identified with the two softwares contained 29 common CNVRs in CIN and 17 co…

A combined genome-wide approach identifies a new potential candidate marker associated with the coat color sidedness in cattle

2019

Abstract Coat color is one of the most important phenotypic features in livestock breeds. Cinisara is a local cattle breed generally of uniform black color which occasionally presents a particular phenotype, with animals typically display a white band along their spine, from the head to the tail, and on the ventral line (color sidedness). Therefore, this breed provides an ideal model to study the genetic components underlying phenotypic variation in coat color. A total of 63 animals, ten with sidedness phenotype and 53 with uniform black color were genotyped with Illumina Bovine 50 K. The comparison among genome-wide association study and FST analysis revealed a single nucleotide polymorphi…

Detection of genomic regions underlying milk production traits in Valle del Belice dairy sheep using regional heritability mapping

2021

The aim of this study was to identify genomic regions underlying milk production traits in the Valle del Belice dairy sheep using regional heritability mapping (RHM). Repeated measurements for milk yield (MY), fat percentage and yield (F% and FY) and protein percentage and yield (P% and PY), collected over a period of six years (2006-2012) on 481 Valle del Belice ewes, were used for the analysis. Animals were genotyped with the Illumina 50k SNP chip. Variance components, heritabilities, and repeatability within and across lactations were estimated, fitting parity, litter size, season of lambing, and fortnights in milk, as fixed; and additive genetic, permanent environment within and across …

Genome-wide analyses reveal the regions involved in the phenotypic diversity in Sicilian pigs.

2019

Nero Siciliano (Sicilian Black, SB) is a local pig breed generally of uniform black color. In addition to this officially recognized breed, there are animals showing morphological characteristics resembling the SB but with gray hair (Sicilian Grey, SG). The SG, compared with the SB, also shows a more compact structure with greater transverse diameters, higher average daily gains and lower thickness of the back fat. In this study, using the Illumina PorcineSNP60 BeadChip, we run genome-wide analyses to identify regions that may explain the phenotypic differences between SB (n = 21) and SG (n = 27) individuals. Combining the results of the two case–control approaches (GWAS and FST), we identi…

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…

Full-length sequencing and identification of novel polymorphisms in the ACACA gene of Valle del Belice sheep breed

2017

The essential role of the acetyl-CoA carboxylase (ACACA) enzyme in milk fatty acid (FA) synthesis suggests that it may be responsible for the phenotypic variability observed in milk. Before attempting association analyses between this gene and/or enzyme and phenotypic traits, a study on the genetic variability within this locus is required. The aim of this work was to sequence the entire coding region of ACACA gene in Valle del Belice sheep breed to identify polymorphic sites. A total of 51 coding exons of ACACA gene were sequenced in 32 individuals of Valle del Belice sheep breed. Sequencing analysis and alignment of obtained sequences showed the presence of 23 polymorphic sites. The most …

Effect of Mycoplasma agalactiae mastitis on milk production and composition in Valle dell Belice dairy sheep

2019

Contagious agalactia (CA), a disease caused by Mycoplasma agalactiae and other pathogenic mycoplasmas, is a well-known multietiological syndrome affecting dairy breeds of sheep and goats in the Mediterranean basin. The aim of this work was to study the effect on milk production and composition of mastitis caused by M. agalactiae in Valle del Belice dairy sheep. All ewes were manually milked twice daily and the milk from both daily milking was analysed for milk composition and somatic cell counts. Moreover the morning milk samples were collected aseptically from each animal for bacteriological analyses. A mixed linear model was utilised to consider milk production and composition between ani…

Association study between beta-defensin gene polymorphisms and mastitis resistance in Valle del Belice dairy sheep breed

2016

Abstract Mastitis is generally caused by bacteria, and it is the most common disease in livestock species. Defensins are peptides with a broad spectrum of antimicrobial activity and β-defensin genes have been studied in several livestock species due to their important role in the innate immune response. The aim of this study was to establish an association between polymorphisms in the β-defensin 1 and 2 genes and mastitis resistance in the Valle del Belice dairy sheep. Data consisted of 1855 and 2804 observations for case and control group, respectively. Six single nucleotide polymorphisms and seven haplotypes were selected for association studies with mastitis. In particular, polymorphism …

Genome-Wide Association Study Identifies New Candidate Markers for Somatic Cells Score in a Local Dairy Sheep

2021

In the Mediterranean basin countries, the dairy sheep production is usually based on local breeds, which are very well-adapted to their production systems and environments and can indeed guarantee income, employment, and economic viability in areas where production alternatives are scarce or non-existent. Mastitis is still one of the greatest problems affecting commercial milk production. However, genetic evaluation of mastitis is particularly difficult because of its low heritability and the categorical nature of the trait. The aim of this study was to identify genomic regions putatively associated with somatic cells count (SCC) in the local economically important Valle del Belice sheep br…

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 association study for milk production traits in an economically important local dairy sheep breed

2021

In this study, we conducted a genome-wide association study (GWAS) for five milk production traits in the Valle del Belice sheep. Repeated measurements for milk yield (MY), fat percentage and yield (F% and FY) and protein percentage and yield (P% and PY) on 481 ewes, were available for the analysis. The animals were genotyped using the Illumina Ovine 50k BeadChip. Weighted deregressed breeding values (DEBVw) were used as phenotypes for GWAS analysis. A total of 23 genome-wide significant SNPs were identified: 3 associated with MY, 9 with FY, and 11 with P%. Several SNPs mapped within known candidate genes or previously reported QTL for milk production traits in livestock species. Additional…

Loss in milk yield and related composition changes resulting from different levels of somatic cell count in Valle del Belice dairy sheep

2015

Mastitis is the most common and costly disease in the dairy industry and is responsible for several production effects. Mammary infections cause high somatic cell count (SCC) and severe damage to udder tissue and result in important losses of milk yield and quality, curd and cheese yields in dairy ewes. The aim of this study was to determine the effect of different levels of SCC on milk yield and composition in Valle del Belice dairy sheep. The original data set used for this study included 92,261 records of 6,763 ewes. Data were collected between 1994 and 2006 in 15 flocks. Test-day records of milk yield (MY), fat % (F%), protein % (P%), and SCC were collected following an A4 recording sch…

A pipeline for variants discovery using next-generation DNA sequencing data

2017

Recent advances in next generation sequencing (NGS) technology provide a cost-effective approach to large-scale resequencing of livestock samples in order to study several biological phenomena. NGS produces millions of short DNA sequences that require an unbiased way to make possible comprehensive searches for variation to identify putative causative mutations for economically important traits. The aim of this work was to present a bioinformatics pipeline analysis for variants discovery in ovine genome. A total of 30 individuals belonging to Valle del Belice dairy ewes was used for whole genome sequencing of pooled libraries prepared using Illumina Nextera Kit. Paired-end sequencing was car…

Genome-wide association study for milk production traits in Valle del Belice sheep

2017

Over the last years, high-throughput technologies have provided the opportunity to explore the genomes of livestock species to identify regions influencing traits of economic interest. Genome wide association studies (GWAS) have been widely used to disentangle the genetic variation in complex phenotypes, such as milk production traits in sheep. The study presented here investigated the possible association of genome-wide SNPs and breeding values for milk production traits in the Valle del Belice sheep. The studied population consisted of a total of 481 ewes belonging to 9 half-sib families with available records for milk yield (MY), protein and fat percentage (P% and F%, respectively). All …

Genome wide Copy Number Variation (CNV) detection in Cinisara cattle breed

2017

Copy Number Variations (CNVs) are classes of polymorphic genomic regions including deletions, duplications and insertions of DNA fragments from at least 0.5 kb up to several Mb. CNV represents an important source of genetic variability that provides genomics structural information complementary to the single nucleotide polymorphism (SNP) data. Some CNVs have been shown to be important in both normal phenotypic variability and disease susceptibility in livestock. Several approaches to identify CNVs including FISH, aCGH, SNP array or NGS, were proposed and among these SNP genotyping is relatively low cost, high-throughput and high coverage method. The aim of this study was to identify the CNV…

Polymorphisms at β-defensin genes and mastitis in Valle del Belice dairy sheep: a case control study

2015

Mastitis is the most common and costly pathology affecting dairy animals. The identification of genetic markers that allow the inclusion of mastitis resistance in selection programs would help to reduce the costs due to the disease and the use of antibiotics. In recent years, β-defensin genes have been studied in several domestic species due to their important role in the innate immune response. The aim of this study was to determine whether β-defensin genes variability, β-defensin 1 (SBD1) and β-defensin 2 (SBD2), could distinguish between infected cases and healthy controls in Valle del Belice dairy sheep. Somatic cell count (SCC) is a powerful tool to identify animals with intramammary i…

Comparison of Genome Wide Association Studies for milk production traits in Valle del Belice dairy sheep

The great achievements in livestock species selection during the last 50 years largely relied on quantitative genetic theory and infinitesimal genetic model. In the last 20 years, due to the application of advanced techniques in molecular genetics and statistics, several chromosomal regions that influence quantitative traits have been discovered. Combinations of molecular and classical quantitative information in a composite selection index have been proposed to increase the accuracy of selection. Nowadays, many genotyping arrays for thousands of SNPs are available for several livestock species, such as: cattle, sheep, pigs, horses, goat and chickens. The overall aim of this thesis is the c…

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 …

Variation of proteomic profile during lactation in Girgentana goat milk: a preliminary study

2018

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…