Search results for "dairy sheep"
showing 10 items of 25 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…
A melanocortin 1 receptor (MC1R) gene polymorphism is useful for authentication of Massese sheep dairy products
2011
Massese is an Italian sheep breed, with black or grey coat colour, mainly reared in the Tuscany and Emilia Romagna regions. Recently, the emerging interests in this breed have resulted in the production of Pecorino cheese obtained with only Massese milk. In order to be profitable, this marketing link between Massese breed and its products should be defended against fraudsters who could include milk of other sheep breeds or cow milk in Massese labelled productions. To identify the genetic factors affecting coat colour in sheep, we have recently analysed the melanocortin 1 receptor (MC1R) gene and identified several single nucleotide polymorphisms (SNPs). In this work, as a first step to set …
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,…
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…
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…
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 …
GeneticParameters for Milk Somatic Cell Score and Relationships with Production Traits in Primparous Dairy Sheep
2007
A total of 13,066 first-lactation test-day records of 2,277 Valle del Belice ewes from 17 flocks were used to estimate genetic parameters for somatic cell scores (SCS) and milk production traits, using a repeatability test-day animal model. Heritability estimates were low and ranged from 0.09 to 0.14 for milk, fat, and protein yields, and contents. For SCS, the heritability of 0.14 was relatively high. The repeatabilities were moderate and ranged from 0.29 to 0.47 for milk production traits. The repeatability for SCS was 0.36. Flock-test-day explained a large proportion of the variation for milk production traits, but it did not have a big effect on SCS. The genetic correlations of fat and …
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…