Search results for " Sheep"
showing 10 items of 101 documents
Identification of breed informative single nucleotide polymorphisms for assigning individual in Sicilian dairy sheep
2015
Assignment tests using genetic information to establish population membership of individuals, provide the most direct methods to determine the population of origin of unknown individuals. The identification of the breed or population of origin of individuals potentially offers unbiased tools in livestock and is useful in a variety of biological contexts. The aim of this study was to identify the minimum number of informative SNPs from highthroughput genotyping data in Sicilian dairy sheep breeds, and to investigate their usefulness for breed assignment purposes. Individuals of Valle del Belice (48), Comisana (48) and Pinzirita (53) sheep breeds were genotyped using Illumina OvineSNP50K Geno…
Genetic diversity and phylogenetic relationships among four breeds reared in Sicily using β-lactoglobulin promoter region polymorphisms
2011
The aim of this work was to analyze the genetic diversity and the phylogenetic relationships among the Valle del Belice (VDB) breed and the other sheep breeds considered as ancestors, using -lactoglobulin (BLG) promoter region polymorphisms. The BLG promoter region of 50 randomly chosen animals from the four breeds (VDB n=20; Comisana (COM) n=10; Pinzirita (PIN) n=10; Sarda (SAR) n=10) were sequenced and aligned, and results showed the presence of 36 single nucleotide polymorphisms (SNPs) and one deletion. The number of polymorphic sites identified showed high variability within breeds. Nucleotide (π) and haplotype (Hd) diversity were estimated with DnaSP software, whereas PHASE software w…
Weighted Single-Step Genome-Wide Association Study Uncovers Known and Novel Candidate Genomic Regions for Milk Production Traits and Somatic Cell Sco…
2022
The objective of this study was to uncover genomic regions explaining a substantial proportion of the genetic variance in milk production traits and somatic cell score in a Valle del Belice dairy sheep. Weighted single-step genome-wide association studies (WssGWAS) were conducted for milk yield (MY), fat yield (FY), fat percentage (FAT%), protein yield (PY), protein percentage (PROT%), and somatic cell score (SCS). In addition, our aim was also to identify candidate genes within genomic regions that explained the highest proportions of genetic variance. Overall, the full pedigree consists of 5534 animals, of which 1813 ewes had milk data (15,008 records), and 481 ewes were genotyped with a …
Trend in dairy sheep BLG genotype found with repeatability test-day model.
2007
A total of 19.207 test-days, collected on 4 farms from 1999-2006 and belonging to 1109 Valle del Belice dairy sheep were analyzed with a repeatability model. After strict outlier analysis 17.747 records were retained. Animals were reared in an extensive system resulting in large environmental influences. However, significant genetic variation was detected in production traits (milk production mean=1336 stdg=93 g/d, fat+protein 167 stdg=12 g/d). Heritability was only 3% while the interaction year by month of test-day explained 27% of the variation. A protein and DNA analysis program was initiated in order to facilitate selection to maintain these flocks under these conditions. In total 427 a…
Parentage verification of Valle del Belice dairy sheep using microsatellite markers
2008
The objectives of the present work were to evaluate polymorphism of microsatellite markers, develop a parentage test and estimate misidentification rate on Valle del Belice Sicilian dairy sheep breed. Polymorphism was evaluated from 184 randomly selected animals from 5 different flocks. A total of 21 microsatellite markers including CSRD247, ILST011, McM527, APO010, INRA132, DU194351, DU323541, FCB128, McM16, OarCP49, ILST087, DU223896, ILST005, TCRVB06, SPS113A, INRA063A, SPS115, DU206192, DU216028, BM827 and McM54 were amplified using three PCR reactions and fragment lengths determined in a single multiplex electrophoresis run. Markers were easily genotyped, very polymorphic and in Hardy-…
Selection signatures of fat tail in sheep
2017
The investigation of the genes with a role in lipid metabolism enjoy considerable scientific and commercial interest because of the strong correlations between fat deposition and the risk of cardiovascular disease. The fat tail characteristic of sheep is the adaptive response to harsh environment, and beyond representing a valuable energy reserve for facing future climate changes provides clues for elucidating the physiology of fat deposition. Studies on various sheep populations detected fat-tail signatures on chromosomes 2, 3, 5, 6, 7 and 13. Fat-tailed sheep represent about 25% of the world’s sheep population, and the genes with a role in this phenotype are likely not the same for every …
Application of molecular markers to investigate genetic diversity in Sicilian livestock
2014
La diversità genetica delle specie e razze di interesse zootecnico, rappresenta un’importante risorsa in tutti i sistemi di allevamento . Per lo studio della diversità genetica, nel corso dei decenni sono stati sviluppati diversi metodi che si basano su informazioni del pedigree o su dati molecolari (microsatelliti e SNPs, Single Nucleotide Polymorphisms). Con l’aumento della disponibilità di marcatori molecolari per la maggior parte delle specie di interesse zootecnico, e con lo sviluppo di sofisticate tecniche analitiche, sta crescendo la capacità di caratterizzare la variabilità genetica delle razze. Inoltre, ad oggi, poche sono le informazioni sulla diversità genetica delle razze e dell…
Palatability and in vivo digestibility of Mulberry leaves (Morus latifolia CV. Kokusou 21) in sheep feeding
2007
Mulberry (Morus latifolia L.) leaves and green tops were utilised to study the palatability and the digestibility in two sheep feeding trials. In trial 1 mulberry palatability was determined by cafeteria test, that studies the animal preferences in a short period of time without the interference of post-ingestive factors. Mulberry leaves were tested in respect to vetch hay and oat concentrate; results showed that mulberry leaves were significantly preferred to other feeds. In trial 2 an in vivo digestibility was carried out on 4 rams equipped with the bags for the faeces collection, housed in individual box and fed ad libitum. Results showed that mulberry leaves and green tops were more dig…
Determination of milk production losses in Valle del Belice sheep following experimental infection of Mycoplasma agalactiae
2015
Abstract Economic losses due to contagious agalactia (CA) in small ruminant herds are mainly associated with significant reductions in or complete loss of dairy production, mortality, abortions, ill thrift, early culling and costs of control. With the aim of estimating milk production losses caused by CA, 46 primiparous lactating Valle del Belice ewes were monitored after experimental infection. Sixty days after lambing, two ewes were each experimentally infected with a single dose of 10 8 CFU/ml of a live Mycoplasma agalactiae strain in both teats by intracanalicular route. Three days after inoculation, the infection was spread manually by the milkers dipping their hands in the pooled mil…
Interaction between stearoyl-coenzyme A desaturase polymorphism and feeding system in affecting the fatty acid profile of sheep cheese
2021
Stearoyl-coenzyme A desaturase (SCD) catalyses the synthesis of monounsaturated fatty acids, by introducing a cis double bond at the delta 9–10 position. The study investigated the effects of a polymorphism at the ovine SCD gene and its interaction with the inclusion of fresh forage in the diet on cheese fatty acid (FA) composition in Valle del Belice ewes. A region of 527 bp of the ovine SCD gene including the partial sequence of the promoter, the complete sequence of the 5’ UTR and exon 1 and the partial sequence of intron 1 were analyzed in order to identify the g.87C > A SNP located in the promoter region. A feeding trial was carried out using 16 Valle del Belice ewes selected on the…