Search results for " dairy sheep"
showing 10 items of 15 documents
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…
Parentage verification of Valle del Belice dairy sheep using multiplex microsatellite panel
2013
Abstract The aim of this work was to develop and evaluate a PCR based microsatellite markers multiplex system for parentage verification of Sicilian Valle del Belice dairy sheep. A total of 85 samples of blood and hair were collected and genotyped for 24 microsatellite markers in multiplex electrophoresis runs. A total of 269 alleles were detected across the 24 loci investigated. The PIC considering all loci was equal to 0.736, showing that this microsatellite panel was very polymorphic and highly informative. A parentage test was performed on 64 families generated with multiple sires. Results indicated 20.3% and 29.7% misidentification rates for females and males, respectively. In 8 cases,…
Utilization of mulberry leaves (Morus latifolia cv. Kokusou 21) in diets for dairy ewes
2009
Twelve Valle del Belice lactating ewes were divided into three homogeneous groups and fed ad libitum the following diets in a 3 x 3 Latin square design: sulla hay (HA); sulla hay and Mulberry leaves (M. leaves) (HM); M. leaves (MU). DM intake of MU ewes was lower than that of HM ewes, with an intermediate level for HA ewes. HM ewes showed to prefer M. leaves to hay, but their need to balance the high protein and low NDF contents of M. leaves by eating hay also emerged. Milk yield increased as the dietary content of M. leaves increased- In addition, the use of HM and MU diets led to higher milk fat and urea content in comparison with the HA diet. The results confirmed that M. leaves are a su…
Effect of heat stress on production in Mediterranean dairy sheep
2005
European Mediterranean countries are characterized by exposure to considerable heat between three and six months annually. High ambient temperature, solar radiation, wind speed and relative humidity, cause the effective temperature of the environment to be above the thermo-neutral zone of the animals (5 to 25ºC; McDowell, 1972) and therefore heat stress occurs (Bianca, 1962).
Feeding and management techniques to favour summer sheep milk and cheese production in the Mediterranean environment
2015
Sheep milk production in summer can lead to a diversification of milk products and to a more regular product distribution in the market throughout the year. However, in Mediterranean countries small ruminant production cycles are subjected to seasonal variations in forage resources. During summer, a key period for out of season production systems, nutrition plays a fundamental role in regulating the quantity and quality of milk production. In this review, feeding strategies and techniques that could be applied for out of season production in dairy ewes under different Mediterranean conditions are described for intensive, pasture-based and mixed systems. The most common feeding strategies us…
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…
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…
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…
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 …