http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Mon, 20 May 2013 18:53:04 GMT 2013-05-20T18:53:04Z http://hdl.handle.net/2067/144 Title: Double muscling in Marchigiana beef breed is caused by a stop codon in the third exon of myostatin gene Authors: Marchitelli, Cinzia; Savarese, Maria Carmela; Crisà, Alessandra; Nardone, Alessandro; Ajmone-Marsan, Paolo; Valentini, Alessio Abstract: Double muscling is a partially recessive trait present in some beef breeds. It shows a high frequency in some breeds, while in others the frequency is low, and double-muscled individuals are rare. The double muscling is caused by an allelic series of mutations that cause a loss of function of the myostatin gene (GDF8). We describe here a new mutation in the myostatin gene in Marchigiana breed, a typical beef breed of Central Italy, in which rare double-muscling individuals have been described. A PCR product of the third exon was sequenced in subjects phenotypically showing double muscling, and a C > T transversion was discovered that introduces a premature stop codon. The variant found adds to the large series of mutations present in cattle, and particularly to the only two causative of double muscling in the third exon. A PCR-RFLP test is described for the rapid and effective identification of both heterozygous and homozygous subjects. It was applied to a larger survey carried on the same and also in two other beef breeds, Chianina and Romagnola. Further individuals carrying the new variant were found in Marchigiana, but none in the other breeds. The results may be important for a better comprehension of the role of myostatin in muscular development, for commercial use and for the inference of phylogeny of this gene. Tue, 31 Dec 2002 23:00:00 GMT http://hdl.handle.net/2067/144 2002-12-31T23:00:00Z http://hdl.handle.net/2067/1884 Title: Exploring polymorphisms and effects of candidate genes on milk fat quality in dairy sheep Authors: Crisà, Alessandra; Marchitelli, Cinzia; Pariset, Lorraine; Contarini, Giovanna; Signorelli, Federica; Napolitano, Francesco; Catillo, Gennaro; Valentini, Alessio; Moioli, Bianca Abstract: Aim of the present study was to investigate the genetic control of the fatty acid (FA) composition in milk from three breeds of sheep: Altamurana, Gentile di Puglia and Sarda. SNP within genes, encoding enzymes putatively involved in the synthesis and metabolism of milk fat, were selected for analysis, and the allele substitution effects were determined for 16 genes, that were polymorphic in the three sheep breeds, upon the milk fat composition. Four genes (alpha-1-antichymotrypsin-2; diacylglycerol O-acyltransferase homolog-2; propionyl Coenzyme A carboxylase, beta polypeptide; insulin-like growth factor-I) play a role in the desaturation of stearic FA into polyunsaturated fatty acids (PUFA). Furthermore, two genes (growth hormone receptor and zona pellucida glycoprotein-2) affect the variability of the total fat content, in addition to the butyric and stearic FA profile, and that the fatty acid synthetase gene has an influence on the medium-chain FA. Milk FA profiles play an important role in dairy sheep farming because they have a large effect on cheese characteristics and also because sheep milk may be marketed as a source of nutraceuticals as it contains higher levels of CLA than milk from other ruminants. The current study evaluated the global effects of a large number of SNP and haplotypes on traits that are not commonly investigated in sheep but that are potentially very useful for improving milk quality. Tue, 05 Apr 2011 22:00:00 GMT http://hdl.handle.net/2067/1884 2011-04-05T22:00:00Z http://hdl.handle.net/2067/1924 Title: European cattle breed cluster accordingly to their meat quality parameters Authors: Valentini, Alessio; Nardone, Alessandro; Crisà, Alessandra; Marchitelli, Cinzia; Failla, Sebastiana; Gigli, S.; Albertí, Pere; Sañudo, Carlos; Nutte, G.; Ertbjerg, Per; Hocquette, Jean Francois; Williams, J. L. Abstract: The concept of breed is rather questionable and it’s used more as a tool for “labelling” production systems than as a biological category. Here, production system is intended as a whole set of animal units, techniques, breeding schemes, marketing, etc. However, man has demonstrated to be very quick in capturing and disseminating good characteristics whence they appear in a breed by mutation or by selection. Therefore, it might be expected that breeds, nevertheless of recent origin, could bear distinguished productive characteristics. Due to the quan- titative nature of them, more characteristics should be measured in order to obtain a clear and statistically significant distinction. We have measured several meat characteristics in 15 European breeds (30 individuals for each breed), mostly with beef attitude, reared in similar conditions. This was accomplished to better reveal the genetic background of breeds. A canonical discriminant analysis showed a clear distinction among breeds. In particular lipid composition of meat was able to assign individuals to breeds with 57% and 63% of individuals correctly classified respectively for neutral and phospholipids. The classification is generally good for all breeds except for the Spanish ones,indicating probably some crossing in the past for these breeds. Neutral lipids can classify double muscled breeds with high precision (84% and 95% in Asturiana de los Valles and Piedmontese respectively). Tenderness related measures (collagen, µ-calpain, m-calpain, calpastatin, MFI) poorly assign indi- viduals to breeds (average 22%). The good classification of individuals to breeds for lipid composition suggests distinctive genetic features and encourages to look further to genetic determination of fat composition in the meat, as well as to exploit particular breeds to obtain products suitable for categories of consumers needing/searching for special components in their diet. Thu, 14 Apr 2011 22:00:00 GMT http://hdl.handle.net/2067/1924 2011-04-14T22:00:00Z